Phylogenetic analysis of the lux operon distinguishes two evolutionarily distinct clades of Photobacterium leiognathi.

PubMed

Ast, Jennifer C; Dunlap, Paul V

2004-05-01

The luminous marine bacterium Photobacterium mandapamensis was synonymized several years ago with Photobacterium leiognathi based on a high degree of phenotypic and genetic similarity. To test the possibility that P. leiognathi as now formulated, however, actually contains two distinct bacterial groups reflecting the earlier identification of P. mandapamensis and P. leiognathi as separate species, we compared P. leiognathi strains isolated from light-organ symbiosis with leiognathid fishes (i.e., ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1) with strains from seawater originally described as P. mandapamensis and later synonymized as P. leiognathi (i.e., ATCC 27561(T) and ATCC 33981) and certain strains initially identified as P. leiognathi (i.e., PL-721, PL-741, 554). Analysis of the 16S rRNA and gyrB genes did not resolve distinct clades, affirming a close relationship among these strains. However, strains ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554 were found to bear a luxF gene in the lux operon ( luxABFE), whereas ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1 lack this gene ( luxABE). Phylogenetic analysis of the luxAB(F)E region confirmed this distinction. Furthermore, ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554 all produced a higher level of luminescence on high-salt medium, as previously described for PL-721, whereas ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1 all produced a higher level of luminescence on low-salt medium, a characteristic of P. leiognathi from leiognathid fish light organs. These results demonstrate that P. leiognathi contains two evolutionarily and phenotypically distinct clades, P. leiognathi subsp. leiognathi (strains ATCC 25521(T), ATCC 25587, lequu.1.1 and lleuc.1.1), and P. leiognathi subsp. mandapamensis (strains ATCC 27561(T), ATCC 33981, PL-721, PL-741 and 554).

Variability in growth/no growth boundaries of 188 different Escherichia coli strains reveals that approximately 75% have a higher growth probability under low pH conditions than E. coli O157:H7 strain ATCC 43888.

PubMed

Haberbeck, L U; Oliveira, R C; Vivijs, B; Wenseleers, T; Aertsen, A; Michiels, C; Geeraerd, A H

2015-02-01

This study investigated the variation in growth/no growth boundaries of 188 Escherichia coli strains. Experiments were conducted in Luria-Bertani media under 36 combinations of lactic acid (LA) (0 and 25 mM), pH (3.8, 3.9, 4.0, 4.1, 4.2 and 4.3 for 0 mM LA and 4.3, 4.4, 4.5, 4.6, 4.7 and 4.8 for 25 mM LA) and temperature (20, 25 and 30 °C). After 3 days of incubation, growth was monitored through optical density measurements. For each strain, a so-called purposeful selection approach was used to fit a logistic regression model that adequately predicted the likelihood for growth. Further, to assess the growth/no growth variability for all the strains at once, a generalized linear mixed model was fitted to the data. Strain was fitted as a fixed factor and replicate as a random blocking factor. E. coli O157:H7 strain ATCC 43888 was used as reference strain allowing a comparison with the other strains. Out of the 188 strains tested, 140 strains (∼75%) presented a significantly higher probability of growth under low pH conditions than the O157:H7 strain ATCC 43888, whereas 20 strains (∼11%) showed a significantly lower probability of growth under high pH conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Taxonomic and Strain-Specific Identification of the Probiotic Strain Lactobacillus rhamnosus 35 within the Lactobacillus casei Group▿

PubMed Central

Coudeyras, Sophie; Marchandin, Hélène; Fajon, Céline; Forestier, Christiane

2008-01-01

Lactobacilli are lactic acid bacteria that are widespread in the environment, including the human diet and gastrointestinal tract. Some Lactobacillus strains are regarded as probiotics because they exhibit beneficial health effects on their host. In this study, the long-used probiotic strain Lactobacillus rhamnosus 35 was characterized at a molecular level and compared with seven reference strains from the Lactobacillus casei group. Analysis of rrn operon sequences confirmed that L. rhamnosus 35 indeed belongs to the L. rhamnosus species, and both temporal temperature gradient gel electrophoresis and ribotyping showed that it is closer to the probiotic strain L. rhamnosus ATCC 53103 (also known as L. rhamnosus GG) than to the species type strain. In addition, L. casei ATCC 334 gathered in a coherent cluster with L. paracasei type strains, unlike L. casei ATCC 393, which was closer to L. zeae; this is evidence of the lack of relatedness between the two L. casei strains. Further characterization of the eight strains by pulsed-field gel electrophoresis repetitive DNA element-based PCR identified distinct patterns for each strain, whereas two isolates of L. rhamnosus 35 sampled 40 years apart could not be distinguished. By subtractive hybridization using the L. rhamnosus GG genome as a driver, we were able to isolate five L. rhamnosus 35-specific sequences, including two phage-related ones. The primer pairs designed to amplify these five regions allowed us to develop rapid and highly specific PCR-based identification methods for the probiotic strain L. rhamnosus 35. PMID:18326671

Growth inhibition of oral mutans streptococci and candida by commercial probiotic lactobacilli - an in vitro study

PubMed Central

2010-01-01

Background Probiotic bacteria are suggested to play a role in the maintenance of oral health. Such health promoting bacteria are added to different commercial probiotic products. The aim of the study was to investigate the ability of a selection of lactobacilli strains, used in commercially available probiotic products, to inhibit growth of oral mutans streptococci and C. albicans in vitro. Methods Eight probiotic lactobacilli strains were tested for growth inhibition on three reference strains and two clinical isolates of mutans streptococci as well as two reference strains and three clinical isolates of Candida albicans with an agar overlay method. Results At concentrations ranging from 109 to 105 CFU/ml, all lactobacilli strains inhibited the growth of the mutans streptococci completely with the exception of L. acidophilus La5 that executed only a slight inhibition of some strains at concentrations corresponding to 107 and 105 CFU/ml. At the lowest cell concentration (103 CFU/ml), only L. plantarum 299v and L. plantarum 931 displayed a total growth inhibition while a slight inhibition was seen for all five mutans streptococci strains by L. rhamnosus LB21, L. paracasei F19, L. reuteri PTA 5289 and L. reuteri ATCC 55730. All the tested lactobacilli strains reduced candida growth but the effect was generally weaker than for mutans streptococci. The two L. plantarum strains and L. reuteri ATCC 55730 displayed the strongest inhibition on Candida albicans. No significant differences were observed between the reference strains and the clinical isolates. Conclusion The selected probiotic strains showed a significant but somewhat varying ability to inhibit growth of oral mutans streptococci and Candida albicans in vitro. PMID:20598145

Growth inhibition of oral mutans streptococci and candida by commercial probiotic lactobacilli--an in vitro study.

PubMed

Hasslöf, Pamela; Hedberg, Maria; Twetman, Svante; Stecksén-Blicks, Christina

2010-07-02

Probiotic bacteria are suggested to play a role in the maintenance of oral health. Such health promoting bacteria are added to different commercial probiotic products. The aim of the study was to investigate the ability of a selection of lactobacilli strains, used in commercially available probiotic products, to inhibit growth of oral mutans streptococci and C. albicans in vitro. Eight probiotic lactobacilli strains were tested for growth inhibition on three reference strains and two clinical isolates of mutans streptococci as well as two reference strains and three clinical isolates of Candida albicans with an agar overlay method. At concentrations ranging from 109 to 105 CFU/ml, all lactobacilli strains inhibited the growth of the mutans streptococci completely with the exception of L. acidophilus La5 that executed only a slight inhibition of some strains at concentrations corresponding to 107 and 105 CFU/ml. At the lowest cell concentration (103 CFU/ml), only L. plantarum 299v and L. plantarum 931 displayed a total growth inhibition while a slight inhibition was seen for all five mutans streptococci strains by L. rhamnosus LB21, L. paracasei F19, L. reuteri PTA 5289 and L. reuteri ATCC 55730. All the tested lactobacilli strains reduced candida growth but the effect was generally weaker than for mutans streptococci. The two L. plantarum strains and L. reuteri ATCC 55730 displayed the strongest inhibition on Candida albicans. No significant differences were observed between the reference strains and the clinical isolates. The selected probiotic strains showed a significant but somewhat varying ability to inhibit growth of oral mutans streptococci and Candida albicans in vitro.

Reclassification of Alcaligenes latus strains IAM 12599T and IAM 12664 and Pseudomonas saccharophila as Azohydromonas lata gen. nov., comb. nov., Azohydromonas australica sp. nov. and Pelomonas saccharophila gen. nov., comb. nov., respectively.

PubMed

Xie, Cheng-Hui; Yokota, Akira

2005-11-01

The aim of this study was to clarify the taxonomic position of the nitrogen-fixing and hydrogen-oxidizing bacteria Alcaligenes latus strains IAM 12599T, IAM 12664 and IAM 12665 and Pseudomonas saccharophila IAM 14368T. It was found that the type strain of Alcaligenes latus, IAM 12599T, showed 99 x 9 and 96 x 1 % 16S rRNA gene sequence similarity to strains IAM 12665 and IAM 12664, respectively. A comparison using DNA-DNA hybridization suggested that strains IAM 12599T and IAM 12665 belong to a single species (89 x 7 %) and that strain IAM 12664 (35 x 1 %) forms a separate species. The phenotypic characteristics also support the conclusion that these bacteria should be identified as two species of a new genus: Azohydromonas lata gen. nov., comb. nov. (type strain IAM 12599T=DSM 1122T=LMG 3321T=ATCC 29712T; reference strain IAM 12665=DSM 1123=LMG 3325=ATCC 29714) and Azohydromonas australica sp. nov. (type strain IAM 12664T=DSM 1124T=LMG 3324T=ATCC 29713T). Pseudomonas saccharophila IAM 14368T was found to be closely related to the phototrophic bacterium Roseateles depolymerans, with 96 x 8 % 16S rRNA gene sequence similarity, but the two bacteria are quite different with respect to their metabolism and some significant phenotypic characteristics, suggesting that they cannot be included in a single genus. Further studies on their nifH gene sequences, G+C content of the DNA and cellular fatty acid composition confirm that Pseudomonas saccharophila should be reclassified: the name Pelomonas saccharophila gen. nov., comb. nov. is proposed, with the type strain IAM 14368T (=LMG 2256T=ATCC 15946T).

A genomic island provides Acidithiobacillus ferrooxidans ATCC 53993 additional copper resistance: a possible competitive advantage.

PubMed

Orellana, Luis H; Jerez, Carlos A

2011-11-01

There is great interest in understanding how extremophilic biomining bacteria adapt to exceptionally high copper concentrations in their environment. Acidithiobacillus ferrooxidans ATCC 53993 genome possesses the same copper resistance determinants as strain ATCC 23270. However, the former strain contains in its genome a 160-kb genomic island (GI), which is absent in ATCC 23270. This GI contains, amongst other genes, several genes coding for an additional putative copper ATPase and a Cus system. A. ferrooxidans ATCC 53993 showed a much higher resistance to CuSO(4) (>100 mM) than that of strain ATCC 23270 (<25 mM). When a similar number of bacteria from each strain were mixed and allowed to grow in the absence of copper, their respective final numbers remained approximately equal. However, in the presence of copper, there was a clear overgrowth of strain ATCC 53993 compared to ATCC 23270. This behavior is most likely explained by the presence of the additional copper-resistance genes in the GI of strain ATCC 53993. As determined by qRT-PCR, it was demonstrated that these genes are upregulated when A. ferrooxidans ATCC 53993 is grown in the presence of copper and were shown to be functional when expressed in copper-sensitive Escherichia coli mutants. Thus, the reason for resistance to copper of two strains of the same acidophilic microorganism could be determined by slight differences in their genomes, which may not only lead to changes in their capacities to adapt to their environment, but may also help to select the more fit microorganisms for industrial biomining operations. © Springer-Verlag 2011

[In vitro antibacterial activity of Curcuma longa (Zingiberaceae) against nosocomial bacteria in Montería, Colombia].

PubMed

Méndez Álvarez, Nelson; Angulo Ortíz, Alberto; Contreras Martínez, Orfa

2016-09-01

Bacterial resistance is a growing health problem worldwide that has serious economic and social impacts, compromising public health, and the therapeutic action of current antibiotics. Therefore, the search for new compounds with antimicrobial properties is relevant in modern studies, particularly against bacteria of clinical interest. In the present study, in vitro antibacterial activity of the ethanol extract and essential oil of Curcuma longa (Zingiberaceae) was evaluated against nosocomial bacteria, using the microdilution method. Escherichia coli strains, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus sp. were used, Salmonella sp. and Bacillus sp., isolated from nosocomial infections in a hospital in the city of Monteria and reference strains of S. aureus ATCC 43300, S. aureus ATCC 29213, S. aureus ATCC 25923, P. aeruginosa ATCC 27853, E. coli ATCC 25922 and K. pneumonia ATCC 700603. The ethanol extract antibacterial profile was more efficient at higher concentrations (1 000 ppm), obtaining significant percentages of reduction of more than 50 % against K. pneumoniae ATCC 700603 and a clinical isolate of E. coli; while compared to Bacillus clinical isolate, was more active than the essential oil. For the rest of microorganisms, the reduction percentages obtained at a concentration of 1 000 ppm varied between 17 and 42 % with ethanolic extract, and 8 to 43 % with essential oil. At concentrations of 100 and 500 ppm antibacterial activity of the extracts was lower. The results indicated that the ethanolic extract and essential oil of C. longa rhizomes have active compounds with antibacterial properties that could be used in future research as a therapeutic alternative for the treatment of infections caused by nosocomial pathogens.

Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity.

PubMed

Warda, Alicja K; Siezen, Roland J; Boekhorst, Jos; Wells-Bennik, Marjon H J; de Jong, Anne; Kuipers, Oscar P; Nierop Groot, Masja N; Abee, Tjakko

2016-01-01

We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with 11 additional B. cereus reference genomes to provide an overview of the different types of carbohydrate transporters and utilization systems found in B. cereus strains. The combined application of API tests, defined growth media experiments and comparative genomics enabled us to link the carbohydrate utilisation capacity of 22 B. cereus strains with their genome content and in some cases to the panC phylogenetic grouping. A core set of carbohydrates including glucose, fructose, maltose, trehalose, N-acetyl-glucosamine, and ribose could be used by all strains, whereas utilisation of other carbohydrates like xylose, galactose, and lactose, and typical host-derived carbohydrates such as fucose, mannose, N-acetyl-galactosamine and inositol is limited to a subset of strains. Finally, the roles of selected carbohydrate transporters and utilisation systems in specific niches such as soil, foods and the human host are discussed.

Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity

PubMed Central

Warda, Alicja K.; Siezen, Roland J.; Boekhorst, Jos; Wells-Bennik, Marjon H. J.; de Jong, Anne; Kuipers, Oscar P.; Nierop Groot, Masja N.; Abee, Tjakko

2016-01-01

We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with 11 additional B. cereus reference genomes to provide an overview of the different types of carbohydrate transporters and utilization systems found in B. cereus strains. The combined application of API tests, defined growth media experiments and comparative genomics enabled us to link the carbohydrate utilisation capacity of 22 B. cereus strains with their genome content and in some cases to the panC phylogenetic grouping. A core set of carbohydrates including glucose, fructose, maltose, trehalose, N-acetyl-glucosamine, and ribose could be used by all strains, whereas utilisation of other carbohydrates like xylose, galactose, and lactose, and typical host-derived carbohydrates such as fucose, mannose, N-acetyl-galactosamine and inositol is limited to a subset of strains. Finally, the roles of selected carbohydrate transporters and utilisation systems in specific niches such as soil, foods and the human host are discussed. PMID:27272929

Proposed quality control guidelines for antimicrobial susceptibility tests using tilmicosin.

PubMed Central

Shryock, T R; White, D W; Werner, C S; Staples, J M

1995-01-01

Quality control guidelines for tilmicosin, a novel veterinary-use-only macrolide, were developed in a multi-laboratory study according to established National Committee for Clinical Laboratory Standards (NCCLS) procedures (M23-T2). Tilmicosin was incorporated into Sensititre plates for broth microdilution endpoint testing and into two lots of 15-micrograms disks for Kirby-Bauer agar disk diffusion testing. One common lot and five unique lots of Mueller-Hinton media were used. (Broth was cation adjusted, and agar was supplemented with 5% defibrinated sheep blood.) Bacteria used for reference strains included Pasteurella haemolytica 128K, Pasteurella multocida ATCC 43137, and Staphylococcus aureus ATCC 29213 (microdilution) and ATCC 25923 (disk). Replicate tests were conducted. Disk diffusion and broth microdilution quality control ranges are proposed. PMID:7714188

Design, synthesis and antibacterial activity of cinnamaldehyde derivatives as inhibitors of the bacterial cell division protein FtsZ.

PubMed

Li, Xin; Sheng, Juzheng; Huang, Guihua; Ma, Ruixin; Yin, Fengxin; Song, Di; Zhao, Can; Ma, Shutao

2015-06-05

In an attempt to discover potential antibacterial agents against the increasing bacterial resistance, novel cinnamaldehyde derivatives as FtsZ inhibitors were designed, synthesized and evaluated for their antibacterial activity against nine significant pathogens using broth microdilution method, and their cell division inhibitory activity against four representative strains. In the in vitro antibacterial activity, the newly synthesized compounds generally displayed better efficacy against Staphylococcus aureus ATCC25923 than the others. In particular, compounds 3, 8 and 10 exerted superior or comparable activity to all the reference drugs. In the cell division inhibitory activity, all the compounds showed the same trend as their in vitro antibacterial activity, exhibiting better activity against S. aureus ATCC25923 than the other strains. Additionally, compounds 3, 6, 7 and 8 displayed potent cell division inhibitory activity with an MIC value of below 1 μg/mL, over 256-fold better than all the reference drugs. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Characterization of Aeromonas hydrophila Wound Pathotypes by Comparative Genomic and Functional Analyses of Virulence Genes

PubMed Central

Grim, Christopher J.; Kozlova, Elena V.; Sha, Jian; Fitts, Eric C.; van Lier, Christina J.; Kirtley, Michelle L.; Joseph, Sandeep J.; Read, Timothy D.; Burd, Eileen M.; Tall, Ben D.; Joseph, Sam W.; Horneman, Amy J.; Chopra, Ashok K.; Shak, Joshua R.

2013-01-01

ABSTRACT Aeromonas hydrophila has increasingly been implicated as a virulent and antibiotic-resistant etiologic agent in various human diseases. In a previously published case report, we described a subject with a polymicrobial wound infection that included a persistent and aggressive strain of A. hydrophila (E1), as well as a more antibiotic-resistant strain of A. hydrophila (E2). To better understand the differences between pathogenic and environmental strains of A. hydrophila, we conducted comparative genomic and functional analyses of virulence-associated genes of these two wound isolates (E1 and E2), the environmental type strain A. hydrophila ATCC 7966T, and four other isolates belonging to A. aquariorum, A. veronii, A. salmonicida, and A. caviae. Full-genome sequencing of strains E1 and E2 revealed extensive differences between the two and strain ATCC 7966T. The more persistent wound infection strain, E1, harbored coding sequences for a cytotoxic enterotoxin (Act), a type 3 secretion system (T3SS), flagella, hemolysins, and a homolog of exotoxin A found in Pseudomonas aeruginosa. Corresponding phenotypic analyses with A. hydrophila ATCC 7966T and SSU as reference strains demonstrated the functionality of these virulence genes, with strain E1 displaying enhanced swimming and swarming motility, lateral flagella on electron microscopy, the presence of T3SS effector AexU, and enhanced lethality in a mouse model of Aeromonas infection. By combining sequence-based analysis and functional assays, we characterized an A. hydrophila pathotype, exemplified by strain E1, that exhibited increased virulence in a mouse model of infection, likely because of encapsulation, enhanced motility, toxin secretion, and cellular toxicity. PMID:23611906

Pseudomonas aeruginosa ATCC 9027 is a non-virulent strain suitable for mono-rhamnolipids production.

PubMed

Grosso-Becerra, María-Victoria; González-Valdez, Abigail; Granados-Martínez, María-Jessica; Morales, Estefanía; Servín-González, Luis; Méndez, José-Luis; Delgado, Gabriela; Morales-Espinosa, Rosario; Ponce-Soto, Gabriel-Yaxal; Cocotl-Yañez, Miguel; Soberón-Chávez, Gloria

2016-12-01

Rhamnolipids produced by Pseudomonas aeruginosa are biosurfactants with a high biotechnological potential, but their extensive commercialization is limited by the potential virulence of P. aeruginosa and by restrictions in producing these surfactants in heterologous hosts. In this work, we report the characterization of P. aeruginosa strain ATCC 9027 in terms of its genome-sequence, virulence, antibiotic resistance, and its ability to produce mono-rhamnolipids when carrying plasmids with different cloned genes from the type strain PAO1. The genes that were expressed from the plasmids are those coding for enzymes involved in the synthesis of this biosurfactant (rhlA and rhlB), as well as the gene that codes for the RhlR transcriptional regulator. We confirm that strain ATCC 9027 forms part of the PA7 clade, but contrary to strain PA7, it is sensitive to antibiotics and is completely avirulent in a mouse model. We also report that strain ATCC 9027 mono-rhamnolipid synthesis is limited by the expression of the rhlAB-R operon. Thus, this strain carrying the rhlAB-R operon produces similar rhamnolipids levels as PAO1 strain. We determined that strain ATCC 9027 with rhlAB-R operon was not virulent to mice. These results show that strain ATCC 9027, expressing PAO1 rhlAB-R operon, has a high biotechnological potential for industrial mono-rhamnolipid production.

Revision of the taxonomic status of type strains of Mesorhizobium loti and reclassification of strain USDA 3471T as the type strain of Mesorhizobiumerdmanii sp. nov. and ATCC 33669T as the type strain of Mesorhizobiumjarvisii sp. nov.

PubMed

Martínez-Hidalgo, Pilar; Ramírez-Bahena, Martha Helena; Flores-Félix, José David; Rivas, Raúl; Igual, José M; Mateos, Pedro F; Martínez-Molina, Eustoquio; León-Barrios, Milagros; Peix, Álvaro; Velázquez, Encarna

2015-06-01

The species Mesorhizobim loti was isolated from nodules of Lotus corniculatus and its type strain deposited in several collections. Some of these type strains, such as those deposited in the USDA and ATCC collections before 1990, are not coincident with the original strain, NZP 2213T, deposited in the NZP culture collection. The analysis of the 16S rRNA gene showed that strains USDA 3471T and ATCC 33669T formed independent branches from that occupied by Mesorhizobium loti NZP 2213T and related to those occupied by Mesorhizobium opportunistum WSM2075T and Mesorhizobium huakuii IFO 15243T, respectively, with 99.9 % similarity in both cases. However, the analysis of concatenated recA, atpD and glnII genes with similarities lower than 96, 98 and 94 %, respectively, between strains USDA 3471T and M. opportunistum WSM2075T and between strains ATCC 33669T and M. huakuii IFO 15243T, indicated that the strains USDA 3471T and ATCC 33669T represent different species of the genus Mesorhizobium. These results were confirmed by DNA-DNA hybridization experiments and phenotypic characterization. Therefore, the two strains were reclassified as representatives of the two species Mesorhizobium erdmanii sp. nov. (type strain USDA 3471T = CECT 8631T = LMG 17826t2T) and Mesorhizobium jarvisii sp. nov. (type strain ATCC 33669T = CECT 8632T = LMG 28313T).

Antisense RNA Strategies for Metabolic Engineering of Clostridium acetobutylicum

PubMed Central

Desai, Ruchir P.; Papoutsakis, Eleftherios T.

1999-01-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by ∼100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes. PMID:10049845

Antisense RNA strategies for metabolic engineering of Clostridium acetobutylicum.

PubMed

Desai, R P; Papoutsakis, E T

1999-03-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by approximately 100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes.

Whole-genome mapping reveals a large chromosomal inversion on Iberian Brucella suis biovar 2 strains.

PubMed

Ferreira, Ana Cristina; Dias, Ricardo; de Sá, Maria Inácia Corrêa; Tenreiro, Rogério

2016-08-30

Optical mapping is a technology able to quickly generate high resolution ordered whole-genome restriction maps of bacteria, being a proven approach to search for diversity among bacterial isolates. In this work, optical whole-genome maps were used to compare closely-related Brucella suis biovar 2 strains. This biovar is the unique isolated in domestic pigs and wild boars in Portugal and Spain and most of the strains share specific molecular characteristics establishing an Iberian clonal lineage that can be differentiated from another lineage mainly isolated in several Central European countries. We performed the BamHI whole-genome optical maps of five B. suis biovar 2 field strains, isolated from wild boars in Portugal and Spain (three from the Iberian lineage and two from the Central European one) as well as of the reference strain B. suis biovar 2 ATCC 23445 (Central European lineage, Denmark). Each strain showed a distinct, highly individual configuration of 228-231 BamHI fragments. Nevertheless, a low divergence was globally observed in chromosome II (1.6%) relatively to chromosome I (2.4%). Optical mapping also disclosed genomic events associated with B. suis strains in chromosome I, namely one indel (3.5kb) and one large inversion (944kb). By using targeted-PCR in a set of 176 B. suis strains, including all biovars and haplotypes, the indel was found to be specific of the reference strain ATCC 23445 and the large inversion was shown to be an exclusive genomic marker of the Iberian clonal lineage of biovar 2. Copyright © 2016 Elsevier B.V. All rights reserved.

Antimicrobial potential for the combination of bovine lactoferrin or its hydrolysate with lactoferrin-resistant probiotics against foodborne pathogens.

PubMed

Chen, P-W; Jheng, T T; Shyu, C-L; Mao, F C

2013-03-01

Previous reports have shown that several probiotic strains can resist the antibacterial activity of bovine lactoferrin (bLf), but the results are inconsistent. Moreover, a portion of orally administered apo-bLf is digested in vivo by pepsin to yield bLf hydrolysate, which produces stronger antibacterial activity than that observed with apo-bLf. However, whether bLf hydrolysate affects the growth of probiotic strains is unclear. Therefore, various probiotic strains in Taiwan were collected and evaluated for activity against apo-bLf and bLf hydrolysate in vitro. Thirteen probiotic strains were evaluated, and the growth of Lactobacillus acidophilus ATCC 4356, Lactobacillus salivarius ATCC 11741, Lactobacillus rhamnosus ATCC 53103, Bifidobacterium longum ATCC 15707, and Bifidobacterium lactis BCRC 17394 were inhibited by both apo-bLf and bLf hydrolysate. The growth of 8 strains were not affected by apo-bLf and bLf hydrolysate, including L. rhamnosus ATCC 7469, Lactobacillus reuteri ATCC 23272, Lactobacillus fermentum ATCC 11739, Lactobacillus coryniformis ATCC 25602, L. acidophilus BCRC 14065, Bifidobacterium infantis ATCC 15697, Bifidobacterium bifidum ATCC 29521, and Pediococcus acidilactici ATCC 8081. However, apo-bLf and its hydrolysate inhibited the growth of foodborne pathogens, including Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Enterococcus faecalis. Moreover, the supernatants produced by L. fermentum, B. lactis, and B. longum inhibited the growth of most pathogens. Importantly, a combination of apo-bLf or bLf hydrolysate with the supernatants of cultures of the organisms described above showed synergistic or partially synergistic effects against the growth of most of the selected pathogens. In conclusion, several probiotic strains are resistant to apo-bLf and bLf hydrolysate, warranting clinical studies to evaluate the antimicrobial potential for the combination of apo-bLf or its hydrolysate with specific probiotics. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Sulphate production by Paracoccus pantotrophus ATCC 35512 from different sulphur substrates: sodium thiosulphate, sulphite and sulphide.

PubMed

Meyer, Daniel Derrossi; Andrino, Felipe Gabriel; Possedente de Lira, Simone; Fornaro, Adalgiza; Corção, Gertrudes; Brandelli, Adriano

2016-01-01

One of the problems in waste water treatment plants (WWTPs) is the increase in emissions of hydrogen sulphide (H2S), which can cause damage to the health of human populations and ecosystems. To control emissions of this gas, sulphur-oxidizing bacteria can be used to convert H2S to sulphate. In this work, sulphate detection was performed by spectrophotometry, ion chromatography and atomic absorption spectrometry, using Paracoccus pantotrophus ATCC 35512 as a reference strain growing in an inorganic broth supplemented with sodium thiosulphate (Na2S2O3·5H2O), sodium sulphide (Na2S) or sodium sulphite (Na2SO3), separately. The strain was metabolically competent in sulphate production. However, it was only possible to observe significant differences in sulphate production compared to abiotic control when the inorganic medium was supplemented with sodium thiosulphate. The three methods for sulphate detection showed similar patterns, although the chromatographic method was the most sensitive for this study. This strain can be used as a reference for sulphate production in studies with sulphur-oxidizing bacteria originating from environmental samples of WWTPs.

Screening of the Enterocin-Encoding Genes and Antimicrobial Activity in Enterococcus Species.

PubMed

Ogaki, Mayara Baptistucci; Rocha, Katia Real; Terra, MÁrcia Regina; Furlaneto, MÁrcia Cristina; Maia, Luciana Furlaneto

2016-06-28

In the current study, a total of 135 enterococci strains from different sources were screened for the presence of the enterocin-encoding genes entA, entP, entB, entL50A, and entL50B. The enterocin genes were present at different frequencies, with entA occurring the most frequently, followed by entP and entB; entL50A and L50B were not detected. The occurrence of single enterocin genes was higher than the occurrence of multiple enterocin gene combinations. The 80 isolates that harbor at least one enterocin-encoding gene (denoted "Gene(+) strains") were screened for antimicrobial activity. A total of 82.5% of the Gene(+) strains inhibited at least one of the indicator strains, and the isolates harboring multiple enterocin-encoding genes inhibited a larger number of indicator strains than isolates harboring a single gene. The indicator strains that exhibited growth inhibition included Listeria innocua strain CLIP 12612 (ATCC BAA-680), Listeria monocytogenes strain CDC 4555, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, S. aureus ATCC 29213, S. aureus ATCC 6538, Salmonella enteritidis ATCC 13076, Salmonella typhimurium strain UK-1 (ATCC 68169), and Escherichia coli BAC 49LT ETEC. Inhibition due to either bacteriophage lysis or cytolysin activity was excluded. The growth inhibition of antilisterial Gene+ strains was further tested under different culture conditions. Among the culture media formulations, the MRS agar medium supplemented with 2% (w/v) yeast extract was the best solidified medium for enterocin production. Our findings extend the current knowledge of enterocin-producing enterococci, which may have potential applications as biopreservatives in the food industry due to their capability of controlling food spoilage pathogens.

Survey for collagenase gene prtC in Porphyromonas gingivalis and Porphyromonas endodontalis isolated from endodontic infections.

PubMed

Odell, L J; Baumgartner, J C; Xia, T; David, L L

1999-08-01

Collagenase is a potential virulence factor shown to be expressed by Porphyromonas gingivalis associated with periodontal disease. The purpose of this study was to use the polymerase chain reaction (PCR) to detect the presence of the collagenase gene (prtC) in 21 strains of Porphyromonas species isolated from endodontic infections. Type strains for P. gingivalis (ATCC 33277), P. endodontalis (ATCC 35406), Prevotella intermedia (ATCC 25611), and Prevotella nigrescens (ATCC 33563) were used as controls. When PCR primers specific for the 16S ribosomal RNA gene of P. gingivalis or P. endodontalis were used, 16 of the strains were identified as P. gingivalis, and five strains were identified as P. endodontalis. The presence of the prtC gene for collagenase was detected using PCR. Amplicons were analyzed by agarose gel electrophoresis, with an 815 bp amplicon representing the presence of the collagenase gene. Type strain ATCC 33277 and all 16 clinical isolates of P. gingivalis produced the collagenase gene amplicon. Neither type strain ATCC 35406 nor the five strains from clinical isolates of P. endodontalis produced the collagenase gene amplicon. These results indicate that P. gingivalis from endodontic infections possesses the prtC gene. P. endodontalis does not seem to exhibit prtC. The virulence of P. gingivalis may be related to its production of collagenase.

Thermal resistance of Cronobacter sakazakii isolated from baby food ingredients of dairy origin

USDA-ARS?s Scientific Manuscript database

Milk and whey powders are commonly used ingredients in powdered infant formula (PIF) and follow-up formula (FUF). In this study, Cronobacter sakazakii and Cronobacter dublinensis both of dairy origin and a reference strain, Cronobacter muytjensii ATCC 51329, were investigated for thermal inactivatio...

The status of the species Lactobacillus casei (Orla-Jensen 1916) Hansen and Lessel 1971 and Lactobacillus paracasei Collins et al. 1989. Request for an opinion.

PubMed

Dellaglio, Franco; Felis, Giovanna E; Torriani, Sandra

2002-01-01

On the basis of considerable published evidence, it is concluded that the species Lactobacillus casei is not correctly represented by the strain actually designated as the type strain ATCC 393. It is proposed that the Judicial Commission consider: (1) that ATCC 393T is scientifically unsuitable as the type strain of Lactobacillus casei and should be reclassified as Lactobacillus zeae; (2) that Lactobacillus casei ATCC 334 and Lactobacillus paracasei strains are members of the same taxon and therefore can be united within the name Lactobacillus casei (Rules 42 and 23a), the name Lactobacillus paracasei being rejected; and (3) designating ATCC 334 as the neotype strain for the species

Characterization of Bacteroides forsythus Strains from Cat and Dog Bite Wounds in Humans and Comparison with Monkey and Human Oral Strains

PubMed Central

Hudspeth, M. K.; Gerardo, S. Hunt; Maiden, M. F. J.; Citron, D. M.; Goldstein, E. J. C.

1999-01-01

Bacteroides forsythus strains recovered from cat and dog bite wound infections in humans (n = 3), monkey oral strains (n = 3), and the human oral ATCC 43037 type strain were characterized by using phenotypic characteristics, enzymatic tests, whole cell fatty acid analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, PCR fingerprinting, and 16S rDNA (genes coding for rRNA) sequencing. All three bite wound isolates grew on brucella agar supplemented with 5% sheep blood, vitamin K1, and hemin. These strains, unlike the ATCC strain and previously described monkey oral and human clinical strains, did not require N-acetylmuramic acid supplementation for growth as pure cultures. However, their phenotypic characteristics, except for catalase production, were similar to those of previously identified strains. PCR fingerprinting analysis showed differences in band patterns from the ATCC strain. Also, SDS-PAGE and whole cell fatty acid analysis indicated that the dog and cat bite wound strains were similar but not identical to the human B. forsythus ATCC 43037 type strain and the monkey oral strains. The rDNA sequence analysis indicated that the three bite wound isolates had 99.93% homology with each other and 98.9 and 99.22% homology with the human ATCC 43037 and monkey oral strains, respectively. These results suggest that there are host-specific variations within each group. PMID:10325363

Searching for a potential antibacterial lead structure against bacterial biofilms among new naphthoquinone compounds.

PubMed

Moreira, C S; Silva, A C J A; Novais, J S; Sá Figueiredo, A M; Ferreira, V F; da Rocha, D R; Castro, H C

2017-03-01

The aims of this study were to design, synthesize and to evaluate 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinones against Gram-negative and Gram-positive bacterial strains, including methicillin-resistant Staphylococcus aureus (MRSA) and its biofilm, to probe for potential lead structures. Thirty-six new analogues were prepared with good yields using a simple, fast, operational three-procedure reaction and a thiol addition to an ο-quinone methide using microwave irradiation. All compounds were tested against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Proteus mirabilis ATCC 15290, Serratia marcescens ATCC 14756, Klebsiella pneumoniae ATCC 4352, Enterobacter cloacae ATCC 23355, Enterococcus faecalis ATCC 29212, S. aureus ATCC 25923, Staphylococcus simulans ATCC 27851, Staphylococcus epidermidis ATCC 12228 and a hospital strain of MRSA. Their antibacterial activity was determined using the disc diffusion method, revealing the activity of 19 compounds, mainly against Gram-positive strains. Interestingly, the minimal inhibitory concentration ranges detected for the hit molecules (32-128 μg ml -1 ) were within Clinical and Laboratory Standards Institute levels. Promisingly, compound 15 affected the MRSA strain, with a reduction of up to 50% in biofilm formation, which is better than vancomycin as biofilm forms a barrier against the antibiotic that avoids its action. After probing 36 naphthoquinones for a potential antibacterial lead structure against the bacterial biofilm, we found that compound 15 should be explored further and also should be structurally modified in the near future to test against Gram-negative strains. Since vancomycin is one of the last treatment options currently available, and it is unable to inhibit biofilm, the research of new antimicrobials is urgent. In this context, 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinones proved to be a promising lead structure against MRSA and bacterial biofilm. © 2016 The Society for Applied Microbiology.

Mannitol production by lactic acid bacteria grown in supplemented carob syrup.

PubMed

Carvalheiro, Florbela; Moniz, Patrícia; Duarte, Luís C; Esteves, M Paula; Gírio, Francisco M

2011-01-01

Detailed kinetic and physiological characterisation of eight mannitol-producing lactic acid bacteria, Leuconostoc citreum ATCC 49370, L. mesenteroides subsp. cremoris ATCC19254, L. mesenteroides subsp. dextranicum ATCC 19255, L. ficulneum NRRL B-23447, L. fructosum NRRL B-2041, L. lactis ATCC 19256, Lactobacillus intermedius NRRL 3692 and Lb. reuteri DSM 20016, was performed using a carob-based culture medium, to evaluate their different metabolic capabilities. Cultures were thoroughly followed for 30 h to evaluate consumption of sugars, as well as production of biomass and metabolites. All strains produced mannitol at high yields (>0.70 g mannitol/g fructose) and volumetric productivities (>1.31 g/l h), and consumed fructose and glucose simultaneously, but fructose assimilation rate was always higher. The results obtained enable the studied strains to be divided mainly into two groups: one for which glucose assimilation rates were below 0.78 g/l h (strains ATCC 49370, ATCC 19256 and ATCC 19254) and the other for which they ranged between 1.41 and 1.89 g/l h (strains NRRL B-3692, NRRL B-2041, NRRL B-23447 and DSM 20016). These groups also exhibited different mannitol production rates and yields, being higher for the strains with faster glucose assimilation. Besides mannitol, all strains also produced lactic acid and acetic acid. The best performance was obtained for L. fructosum NRRL B-2041, with maximum volumetric productivity of 2.36 g/l h and the highest yield, stoichiometric conversion of fructose to mannitol.

Comparison of Ribotyping, Randomly Amplified Polymorphic DNA Analysis, and Pulsed-Field Gel Electrophoresis in Typing of Lactobacillus rhamnosus and L. casei Strains

PubMed Central

Tynkkynen, Soile; Satokari, Reetta; Saarela, Maria; Mattila-Sandholm, Tiina; Saxelin, Maija

1999-01-01

A total of 24 strains, biochemically identified as members of the Lactobacillus casei group, were identified by PCR with species-specific primers. The same set of strains was typed by randomly amplified polymorphic DNA (RAPD) analysis, ribotyping, and pulsed-field gel electrophoresis (PFGE) in order to compare the discriminatory power of the methods. Species-specific primers for L. rhamnosus and L. casei identified the type strain L. rhamnosus ATCC 7469 and the neotype strain L. casei ATCC 334, respectively, but did not give any signal with the recently revived species L. zeae, which contains the type strain ATCC 15820 and the strain ATCC 393, which was previously classified as L. casei. Our results are in accordance with the suggested new classification of the L. casei group. Altogether, 21 of the 24 strains studied were identified with the species-specific primers. In strain typing, PFGE was the most discriminatory method, revealing 17 genotypes for the 24 strains studied. Ribotyping and RAPD analysis yielded 15 and 12 genotypes, respectively. PMID:10473394

Comparison of ribotyping, randomly amplified polymorphic DNA analysis, and pulsed-field gel electrophoresis in typing of Lactobacillus rhamnosus and L. casei strains.

PubMed

Tynkkynen, S; Satokari, R; Saarela, M; Mattila-Sandholm, T; Saxelin, M

1999-09-01

A total of 24 strains, biochemically identified as members of the Lactobacillus casei group, were identified by PCR with species-specific primers. The same set of strains was typed by randomly amplified polymorphic DNA (RAPD) analysis, ribotyping, and pulsed-field gel electrophoresis (PFGE) in order to compare the discriminatory power of the methods. Species-specific primers for L. rhamnosus and L. casei identified the type strain L. rhamnosus ATCC 7469 and the neotype strain L. casei ATCC 334, respectively, but did not give any signal with the recently revived species L. zeae, which contains the type strain ATCC 15820 and the strain ATCC 393, which was previously classified as L. casei. Our results are in accordance with the suggested new classification of the L. casei group. Altogether, 21 of the 24 strains studied were identified with the species-specific primers. In strain typing, PFGE was the most discriminatory method, revealing 17 genotypes for the 24 strains studied. Ribotyping and RAPD analysis yielded 15 and 12 genotypes, respectively.

Draft Genome Sequence for ICMP 5702, the Type Strain of Pectobacterium carotovorum subsp. carotovorum That Causes Soft Rot Disease on Potato

PubMed Central

Lu, Ashley; Armstrong, Karen F.

2015-01-01

Pectobacterium species are economically important bacteria that cause soft rotting of potato tubers in the field and in storage. Here, we report the draft genome sequence of the type strain for P. carotovorum subsp. carotovorum, ICMP 5702 (ATCC 15713). The genome sequence of ICMP 5702 will provide an important reference for future phylogenomic and taxonomic studies of the phytopathogenic Enterobacteriaceae. PMID:26251498

Enhancing activity of antibiotics against Staphylococcus aureus: Zanthoxylum capense constituents and derivatives.

PubMed

Cabral, Vanessa; Luo, Xuan; Junqueira, Elisabete; Costa, Sofia S; Mulhovo, Silva; Duarte, Aida; Couto, Isabel; Viveiros, Miguel; Ferreira, Maria-José U

2015-04-15

Six compounds (1-6), isolated from the methanol extract of the roots of the African medicinal plant Zanthoxylum capense Thunb. (Rutaceae), and seven ester derivatives (7-13) were evaluated for their antibacterial activities and modulatory effects on the MIC of antibiotics (erythromycin, oxacillin, and tetracycline) and ethidium bromide (EtBr) against a Staphylococcus aureus reference strain (ATCC 6538). Using the same model, compounds 1-13 were also assessed for their potential as efflux pump inhibitors by a fluorometric assay that measures the accumulation of the broad range efflux pump substrate EtBr. Compounds 8 and 11 were further evaluated for their antibacterial, modulatory and EtBr accumulation effects against four additional S. aureus strains, which included two clinical methicillin-resistant S. aureus (MRSA) strains. Compounds (1-13) have not shown antibacterial activity at the concentration ranges tested. When evaluated against S. aureus ATCC 6538, oxychelerythrine (1) a benzophenanthridine alkaloid, showed the highest modulatory activity enhancing the susceptibility of this strain to all the tested antibiotics from two to four-fold. Ailanthoidiol diacetate (8) and ailanthoidiol di-2-ethylbutanoate (11) were also good modulators when combined with EtBr, increasing the bacteria susceptibility by four and two-fold, respectively. In the EtBr accumulation assay, using ATCC 6538 strain, the phenylpropanoid (+)-ailanthoidiol (6) and most of its ester derivatives (8-11) exhibited higher activity than the positive control verapamil. The highest effects were found for compounds 8 and 11 that also increased the accumulation of EtBr, using S. aureus ATCC 25923 as model. Furthermore, both compounds (8, 11) were able to enhance the ciprofloxacin activity against the MRSA clinical strains tested, causing a reduction of the antibiotic MIC values from two to four-fold. The EtBr accumulation assay revealed that this modulation activity was not due to an inhibition of efflux pumps mechanism. These results suggested that Z. capense constituents may be valuable as leads for restoring antibiotic activity against MRSA strains. Copyright © 2015 Elsevier GmbH. All rights reserved.

Malic acid production from thin stillage by Aspergillus species.

PubMed

West, Thomas P

2011-12-01

The ability of Aspergillus strains to utilize thin stillage to produce malic acid was compared. The highest malic acid was produced by Aspergillus niger ATCC 9142 at 17 g l(-1). Biomass production from thin stillage was similar with all strains but ATCC 10577 was the highest at 19 g l(-1). The highest malic acid yield (0.8 g g(-1)) was with A. niger ATCC 9142 and ATCC 10577 on the stillage. Thus, thin stillage has the potential to act as a substrate for the commercial production of food-grade malic acid by the A. niger strains. © Springer Science+Business Media B.V. 2011

Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria.

PubMed

Gilardi, G L; Faur, Y C

1984-10-01

Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. The remaining seven strains represented an undescribed taxon. These pink bacteria appear to be invaders of debilitated patients with an underlying chronic disease.

Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria.

PubMed Central

Gilardi, G L; Faur, Y C

1984-01-01

Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. The remaining seven strains represented an undescribed taxon. These pink bacteria appear to be invaders of debilitated patients with an underlying chronic disease. PMID:6490848

Isolation of a new heterolobosean amoeba from a rice field soil: Vrihiamoeba italica gen. nov., sp. nov.

PubMed

Murase, Jun; Kawasaki, Michio; De Jonckheere, Johan F

2010-08-01

A heterolobosean amoeba strain 6_5F was isolated from an Italian rice field soil. Although 18S rRNA gene sequence analysis demonstrated that the new isolate was closely related to Stachyamoeba sp. ATCC 50324, further molecular analysis and morphological observation showed distinct differences amongst the two. The 5.8S rRNA gene was successfully amplified and sequenced for strain 6_5F but not for strain ATCC 50324. Trophozoites of strain ATCC 50324 transform into flagellate forms in the late stage of incubation before encystment, while strain 6_5F do not show flagellate forms under different conditions of the flagellation test. Light and electron microscopic observation showed the structural difference of cysts of strain 6_5F from strain ATCC 50324 and also from the type strain Stachyamoeba lipophora. The results show that the strain 6_5F is distinct from Stachyamoeba spp. and we propose a new genus and species for this isolate, Vrihiamoeba italica gen. nov., sp. nov. Copyright (c) 2010 Elsevier GmbH. All rights reserved.

Enterococcus Xinjiangensis sp. nov., Isolated from Yogurt of Xinjiang, China.

PubMed

Ren, Xiaopu; Li, Mingyang; Guo, Dongqi

2016-09-01

A Gram-strain-positive bacterial strain 48(T) was isolated from traditional yogurt in Xinjiang Province, China. The bacterium was characterized by a polyphasic approach, including 16S rRNA gene sequence analysis, polymerase α subunit (rpoA) gene sequence analysis, determination of DNA G+C content, DNA-DNA hybridization with the type strain of Enterococcus ratti and analysis of phenotypic features. Strain 48(T) accounted for 96.1, 95.8, 95.8, and 95.7 % with Enterococcus faecium CGMCC 1.2136(T), Enterococcus hirae ATCC 9790(T), Enterococcus durans CECT 411(T), and E. ratti ATCC 700914(T) in the 16S rRNA gene sequence similarities, respectively. The sequence of rpoA gene showed similarities of 99.0, 96.0, 96.0, and 96 % with that of E. faecium ATCC 19434(T), Enterococcus villorum LMG12287, E. hirae ATCC 9790(T), and E. durans ATCC 19432(T), respectively. Based upon of polyphasic characterization data obtained in the study, a novel species, Enterococcus xinjiangensis sp. nov., was proposed and the type strain was 48(T)(=CCTCC AB 2014041(T) = JCM 30200(T)).

Complete Genome Sequence of the Quality Control Strain Staphylococcus aureus subsp. aureus ATCC 25923

PubMed Central

Treangen, Todd J.; Maybank, Rosslyn A.; Enke, Sana; Friss, Mary Beth; Diviak, Lynn F.; Karaolis, David K. R.; Koren, Sergey; Ondov, Brian; Phillippy, Adam M.; Bergman, Nicholas H.

2014-01-01

Staphylococcus aureus subsp. aureus ATCC 25923 is commonly used as a control strain for susceptibility testing to antibiotics and as a quality control strain for commercial products. We present the completed genome sequence for the strain, consisting of the chromosome and a 27.5-kb plasmid. PMID:25377701

Novel depsides as potential anti-inflammatory agents with potent inhibitory activity against Escherichia coli-induced interleukin-8 production.

PubMed

Lv, Peng-Cheng; Xiong, Jing; Chen, Jin; Wang, Kai-Rui; Mao, Wen-Jun; Zhu, Hai-Liang

2010-08-01

Sixteen novel depsides were synthesized for the first time. Their chemical structures were clearly determined by (1)H NMR, ESI mass spectra, and elemental analyses. All the compounds were assayed for antibacterial activities against three Gram-positive bacterial strains (Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538, and Streptococcus faecalis ATCC 9790) and three Gram-negative bacterial strains (Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 13525, and Enterobacter cloacae ATCC 13047) by the MTT method. Compound 2-(2-methoxy-2-oxoethyl)phenyl 5-bromonicotinate (5) exhibited significant antibacterial activities against E. coli ATCC 35218 with an MIC of 0.78 microg/mL, which was superior to the positive control kanamycin B. In addition, compound 5 showed potent inhibitory activity against E. coli-induced interleukin-8 production.

Streptosporangium minutum sp. nov., isolated from garden soil exposed to microwave radiation.

PubMed

Le Roes-Hill, Marilize; Durrell, Kim; Prins, Alaric; Meyers, Paul R

2018-06-01

The actinobacterium, strain M26 T , was isolated from garden soil that was pre-treated with microwave radiation. The soil sample was collected in Roodepoort, Gauteng Province, South Africa as part of an antibiotic-screening programme. The isolate produced branched vegetative mycelium with sporangiophores bearing small sporangia ranging from 3 to 6 μm in diameter. Rapid genus identification revealed that the isolate belongs to the genus Streptosporangium. To confirm this result, the strain was subjected to polyphasic taxonomic characterisation. Chemotaxonomic characteristics were as follows: meso-DAP in the peptidoglycan, the whole-cell hydrolysate yielded madurose, predominant menaquinones were MK9 (21%), MK9(H 2 ) (40%), MK9(H 4 ) (31%) and MK9(H 6 ) (3%); the polar lipid profile included an aminolipid, phosphoglycolipids, phosphatidylethanolamine, and phosphatidylmonomethylethanolamine. In addition, the fatty acid profile showed the presence of C 16:0 (12.8%), C 17:1 ω8c (14.2%), and 10-methyl-C 17:0 (15.8%). Furthermore, 16S rRNA gene sequence phylogenetic analysis showed that the strain is closely related to members of the genus Streptosporangium, which supports its classification within the family Streptosporangiaceae. Strain M26 T exhibited antibiosis against a range of pathogenic bacteria, including, but not limited to Acinetobacter baumannii ATCC 19606 T , Enterobacter cloacae subsp. cloacae ATCC BAA-1143, Enterococcus faecalis ATCC 51299 (vancomycin resistant), Escherichia coli ATCC 25922, Listeria monocytogenes ATCC 19111, Mycobacterium tuberculosis H37Rv T , Pseudomonas aeruginosa ATCC 27853, Salmonella enterica subsp. arizonae ATCC 13314 T , and the methicillin-resistant Staphylococcus aureus subsp. aureus ATCC 33591 (MRSA). The name Streptosporangium minutum is proposed with the type strain M26 T (=LMG 28850 T =NRRL B-65295 T ).

Complete Genome Sequence of the Quality Control Strain Staphylococcus aureus subsp. aureus ATCC 25923.

PubMed

Treangen, Todd J; Maybank, Rosslyn A; Enke, Sana; Friss, Mary Beth; Diviak, Lynn F; Karaolis, David K R; Koren, Sergey; Ondov, Brian; Phillippy, Adam M; Bergman, Nicholas H; Rosovitz, M J

2014-11-06

Staphylococcus aureus subsp. aureus ATCC 25923 is commonly used as a control strain for susceptibility testing to antibiotics and as a quality control strain for commercial products. We present the completed genome sequence for the strain, consisting of the chromosome and a 27.5-kb plasmid. Copyright © 2014 Treangen et al.

Susceptibility of Blastomyces dermatitidis strains to products of oxidative metabolism.

PubMed

Sugar, A M; Chahal, R S; Brummer, E; Stevens, D A

1983-09-01

Three strains of Blastomyces dermatitidis which differ in their virulence for mice were exposed in their yeast form to various components of the peroxidase-hydrogen peroxide-halide system. Susceptibility to H2O2 alone correlated with virulence, with the most virulent strain (ATCC 26199) least susceptible (50% lethal dose, greater than 50 mM) and an avirulent strain (ATCC 26197) most susceptible (50% lethal dose less than 3.3 mM). A strain of intermediate virulence (ATCC 26198) was of intermediate susceptibility (50% lethal dose, 11.5 mM). The addition of a nontoxic concentration of KI (5 X 10(-4) M) did not increase H2O2 toxicity. However, the addition of either myeloperoxidase or horseradish peroxidase and KI markedly decreased the amount of H2O2 required to kill the organisms, with 100 +/- 0% of all strains killed at 5 X 10(-5) M H2O2 and 97 +/- 4, 100 +/- 0, and 94 +/- 8% of ATCC 26199, ATCC 26198, and ATCC 26197 killed, respectively, at 5 X 10(-6) M H2O2. Kinetic studies with H2O2 alone revealed a delayed onset of killing, but virtually 100% of organisms were killed by 120 min of exposure in all strains. By comparison, the peroxidase-hydrogen peroxide-halide system was 100% lethal for all strains at 1 min. The relatively high concentrations of H2O2 required to kill the yeast phase of B. dermatitidis suggest that H2O2 alone does not account for host resistance to the organism. However, the rapidly lethal effect of the peroxidase-hydrogen peroxide-halide system at physiologically relevant concentrations suggests that this may be one mechanism of host defense to B. dermatitidis.

Do different strains of E. faecalis have the same behavior towards intracanal medications in in vitro research?

PubMed

Zancan, Rafaela Fernandes; Canali, Lyz Cristina Furquim; Tartari, Talita; Andrade, Flaviana Bombarda de; Vivan, Rodrigo Ricci; Duarte, Marco Antonio Hungaro

2018-05-24

The aim of this study was to evaluate the antimicrobial action of different endodontic pastes against Enterococcus faecalis ATCC 29212, isolated from the urinary tract, and compare the action with E. faecalis ATCC 4083, isolated from the root canal. For this purpose, dentin blocks were infected for 21 days with both bacteria at different time-intervals to ensure there would be no cross contamination. After this period, blocks were immersed in the test medications for 7 days, according to the following groups: CH/S, CH/P, CH/CMCP, CH/CHX, CH/DAP and TAP. Images of the samples were captured with a confocal microscope and the percentage of live cells was computed by means of the Bioimage program. The ATCC 29212 strain was shown to be more resistant to CH/SS, Calen, CH/DAP, and TAP than the ATCC 4083 strain. The antimicrobial action of the medications against each strain were divergent concerning the order of susceptibility. The authors concluded that the strains behaved in a different manner: in general, those extracted from the urinary tract were more resistant to the tested medications. Therefore, when E. faecalis must be used for in vitro research in endodontics, we suggest the use of ATCC 4083 strain to obtain results that are closer to the clinical reality.

Genetically enhanced cellulase production in Pseudomonas cellulosa using recombinant DNA technology

DOEpatents

Dees, H. Craig

1999-01-01

An enhanced strain of Pseudomonas celllulosa was obtained by introducing a recombinant genetic construct comprising a heterologous cellulase gene operably connected to a promoter into ATCC 55702, mutagenizing the transformants by treatment with MNNG, and selecting a high cellulase producing transformant. The transformant, designated Pseudomonas cellulosa ATCC XXXX, exhibits enhanced levels of cellulase production relative to the untransformed Pseudomonas cellulosa strain #142 ATCC 55702.

Evaluation of the in vitro activity of ceragenins against Trichomonas vaginalis.

PubMed

Polat, Zubeyde Akin; Cetin, Ali; Savage, Poul B

2016-03-01

Trichomonosis, caused by the protozoan parasite Trichomonas vaginalis, is a curable sexually transmitted disease that is most commonly encountered worldwide. Increasing importance of trichomoniasis and emerging of resistance against metronidazole lead to search for alternative drugs with different mode of activity. The purpose of this study was to determine in vitro activity of ceragenins (CSA-13, CSA-44, CSA-13, and CSA-138) against the metronidazole-susceptible (ATCC 30001) and metronidazole-resistant (ATCC 50138) strains of T. vaginalis. The effective concentrations were evaluated using two strains of T. vaginalis with different metronidazole susceptibilities (ATCC 30001 and ATCC 50138) in the presence of dilution series of ceragenins in 24-well microtitre assays. Overall, all the ceragenins killed the metronidazole-susceptible (ATCC 30001) and metronidazole-resistant (ATCC 50138) strains of T. vaginalis (p>0.05). With regard to the their effects against the studied strains of T. vaginalis, in order of effectiveness, overall, the ceragenins ordered as CSA-13 (the most effective), CSA-131 and CSA-138 (effective similarly), and CSA-44 (the least effective) (p<0.05). All of the ceragenins reduced the trophozoite numbers of both of studied strains of T. vaginalis with a time- and dose- dependent manner (p<0.05). Although all of the study ceragenins, CSA-13, CSA-44, CSA-13, and CSA-138, killed the studied strains of T. vaginalis. CSA-13 is the leading ceragenin as the most effective anti-trichomonas compound, followed by CSA-131 and CSA-138. They have a potential to have a place in the armemantarium of gynecologic and urologic practice for the management of sexually transmitted diseases.

Digital antimicrobial susceptibility testing using the MilliDrop technology.

PubMed

Jiang, L; Boitard, L; Broyer, P; Chareire, A-C; Bourne-Branchu, P; Mahé, P; Tournoud, M; Franceschi, C; Zambardi, G; Baudry, J; Bibette, J

2016-03-01

We present the MilliDrop Analyzer (MDA), a droplet-based millifluidic system for digital antimicrobial susceptibility testing (D-AST), which enables us to determine minimum inhibitory concentrations (MICs) precisely and accurately. The MilliDrop technology was validated by using resazurin for fluorescence readout, for comparison with standard methodology, and for conducting reproducibility studies. In this first assessment, the susceptibility of a reference Gram-negative strain Escherichia coli ATCC 25922 to gentamicin, chloramphenicol, and nalidixic acid were tested by the MDA, VITEK®2, and broth microdilution as a reference standard. We measured the susceptibility of clinically relevant Gram-positive strains of Staphylococcus aureus to vancomycin, including vancomycin-intermediate S. aureus (VISA), heterogeneous vancomycin-intermediate S. aureus (hVISA), and vancomycin-susceptible S. aureus (VSSA) strains. The MDA provided results which were much more accurate than those of VITEK®2 and standard broth microdilution. The enhanced accuracy enabled us to reliably discriminate between VSSA and hVISA strains.

Intraspecies Variability Affects Heterotypic Biofilms of Porphyromonas gingivalis and Prevotella intermedia: Evidences of Strain-Dependence Biofilm Modulation by Physical Contact and by Released Soluble Factors

PubMed Central

Barbosa, Graziela Murta; Colombo, Andrea Vieira; Rodrigues, Paulo Henrique; Simionato, Maria Regina Lorenzetti

2015-01-01

It is well known that strain and virulence diversity exist within the population structure of Porphyromonas gingivalis. In the present study we investigate intra- and inter-species variability in biofilm formation of Porphyromonas gingivalis and partners Prevotella intermedia and Prevotella nigrescens. All strains tested showed similar hydrophobicity, except for P. gingivalis W83 which has roughly half of the hydrophobicity of P. gingivalis ATCC33277. An intraspecies variability in coaggregation of P. gingivalis with P. intermedia was also found. The association P. gingivalis W83/P. intermedia 17 produced the thickest biofilm and strain 17 was prevalent. In a two-compartment system P. gingivalis W83 stimulates an increase in biomass of strain 17 and the latter did not stimulate the growth of P. gingivalis W83. In addition, P. gingivalis W83 also stimulates the growth of P. intermedia ATCC25611 although strain W83 was prevalent in the association with P. intermedia ATCC25611. P. gingivalis ATCC33277 was prevalent in both associations with P. intermedia and both strains of P. intermedia stimulate the growth of P. gingivalis ATCC33277. FISH images also showed variability in biofilm structure. Thus, the outcome of the association P. gingivalis/P. intermedia seems to be strain-dependent, and both soluble factors and physical contact are relevant. The association P. gingivalis-P. nigrescens ATCC33563 produced larger biomass than each monotypic biofilm, and P. gingivalis was favored in consortia, while no differences were found in the two-compartment system. Therefore, in consortia P. gingivalis-P. nigrescens physical contact seems to favor P. gingivalis growth. The intraspecies variability found in our study suggests strain-dependence in ability of microorganisms to recognize molecules in other bacteria which may further elucidate the dysbiosis event during periodontitis development giving additional explanation for periodontal bacteria, such as P. gingivalis and P. intermedia, among others, to persist and establish chronic infections in the host. PMID:26406499

Intraspecies Variability Affects Heterotypic Biofilms of Porphyromonas gingivalis and Prevotella intermedia: Evidences of Strain-Dependence Biofilm Modulation by Physical Contact and by Released Soluble Factors.

PubMed

Barbosa, Graziela Murta; Colombo, Andrea Vieira; Rodrigues, Paulo Henrique; Simionato, Maria Regina Lorenzetti

2015-01-01

It is well known that strain and virulence diversity exist within the population structure of Porphyromonas gingivalis. In the present study we investigate intra- and inter-species variability in biofilm formation of Porphyromonas gingivalis and partners Prevotella intermedia and Prevotella nigrescens. All strains tested showed similar hydrophobicity, except for P. gingivalis W83 which has roughly half of the hydrophobicity of P. gingivalis ATCC33277. An intraspecies variability in coaggregation of P. gingivalis with P. intermedia was also found. The association P. gingivalis W83/P. intermedia 17 produced the thickest biofilm and strain 17 was prevalent. In a two-compartment system P. gingivalis W83 stimulates an increase in biomass of strain 17 and the latter did not stimulate the growth of P. gingivalis W83. In addition, P. gingivalis W83 also stimulates the growth of P. intermedia ATCC25611 although strain W83 was prevalent in the association with P. intermedia ATCC25611. P. gingivalis ATCC33277 was prevalent in both associations with P. intermedia and both strains of P. intermedia stimulate the growth of P. gingivalis ATCC33277. FISH images also showed variability in biofilm structure. Thus, the outcome of the association P. gingivalis/P. intermedia seems to be strain-dependent, and both soluble factors and physical contact are relevant. The association P. gingivalis-P. nigrescens ATCC33563 produced larger biomass than each monotypic biofilm, and P. gingivalis was favored in consortia, while no differences were found in the two-compartment system. Therefore, in consortia P. gingivalis-P. nigrescens physical contact seems to favor P. gingivalis growth. The intraspecies variability found in our study suggests strain-dependence in ability of microorganisms to recognize molecules in other bacteria which may further elucidate the dysbiosis event during periodontitis development giving additional explanation for periodontal bacteria, such as P. gingivalis and P. intermedia, among others, to persist and establish chronic infections in the host.

Phylogeny of 54 representative strains of species in the family Pasteurellaceae as determined by comparison of 16S rRNA sequences.

PubMed Central

Dewhirst, F E; Paster, B J; Olsen, I; Fraser, G J

1992-01-01

Virtually complete 16S rRNA sequences were determined for 54 representative strains of species in the family Pasteurellaceae. Of these strains, 15 were Pasteurella, 16 were Actinobacillus, and 23 were Haemophilus. A phylogenetic tree was constructed based on sequence similarity, using the Neighbor-Joining method. Fifty-three of the strains fell within four large clusters. The first cluster included the type strains of Haemophilus influenzae, H. aegyptius, H. aphrophilus, H. haemolyticus, H. paraphrophilus, H. segnis, and Actinobacillus actinomycetemcomitans. This cluster also contained A. actinomycetemcomitans FDC Y4, ATCC 29522, ATCC 29523, and ATCC 29524 and H. aphrophilus NCTC 7901. The second cluster included the type strains of A. seminis and Pasteurella aerogenes and H. somnus OVCG 43826. The third cluster was composed of the type strains of Pasteurella multocida, P. anatis, P. avium, P. canis, P. dagmatis, P. gallinarum, P. langaa, P. stomatis, P. volantium, H. haemoglobinophilus, H. parasuis, H. paracuniculus, H. paragallinarum, and A. capsulatus. This cluster also contained Pasteurella species A CCUG 18782, Pasteurella species B CCUG 19974, Haemophilus taxon C CAPM 5111, H. parasuis type 5 Nagasaki, P. volantium (H. parainfluenzae) NCTC 4101, and P. trehalosi NCTC 10624. The fourth cluster included the type strains of Actinobacillus lignieresii, A. equuli, A. pleuropneumoniae, A. suis, A. ureae, H. parahaemolyticus, H. parainfluenzae, H. paraphrohaemolyticus, H. ducreyi, and P. haemolytica. This cluster also contained Actinobacillus species strain CCUG 19799 (Bisgaard taxon 11), A. suis ATCC 15557, H. ducreyi ATCC 27722 and HD 35000, Haemophilus minor group strain 202, and H. parainfluenzae ATCC 29242. The type strain of P. pneumotropica branched alone to form a fifth group. The branching of the Pasteurellaceae family tree was quite complex. The four major clusters contained multiple subclusters. The clusters contained both rapidly and slowly evolving strains (indicated by differing numbers of base changes incorporated into the 16S rRNA sequence relative to outgroup organisms). While the results presented a clear picture of the phylogenetic relationships, the complexity of the branching will make division of the family into genera a difficult and somewhat subjective task. We do not suggest any taxonomic changes at this time. PMID:1548238

Transcriptome and Gene Ontology (GO) Enrichment Analysis Reveals Genes Involved in Biotin Metabolism That Affect L-Lysine Production in Corynebacterium glutamicum.

PubMed

Kim, Hong-Il; Kim, Jong-Hyeon; Park, Young-Jin

2016-03-09

Corynebacterium glutamicum is widely used for amino acid production. In the present study, 543 genes showed a significant change in their mRNA expression levels in L-lysine-producing C. glutamicum ATCC21300 than that in the wild-type C. glutamicum ATCC13032. Among these 543 differentially expressed genes (DEGs), 28 genes were up- or downregulated. In addition, 454 DEGs were functionally enriched and categorized based on BLAST sequence homologies and gene ontology (GO) annotations using the Blast2GO software. Interestingly, NCgl0071 (bioB, encoding biotin synthase) was expressed at levels ~20-fold higher in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain. Five other genes involved in biotin metabolism or transport--NCgl2515 (bioA, encoding adenosylmethionine-8-amino-7-oxononanoate aminotransferase), NCgl2516 (bioD, encoding dithiobiotin synthetase), NCgl1883, NCgl1884, and NCgl1885--were also expressed at significantly higher levels in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain, which we determined using both next-generation RNA sequencing and quantitative real-time PCR analysis. When we disrupted the bioB gene in C. glutamicum ATCC21300, L-lysine production decreased by approximately 76%, and the three genes involved in biotin transport (NCgl1883, NCgl1884, and NCgl1885) were significantly downregulated. These results will be helpful to improve our understanding of C. glutamicum for industrial amino acid production.

Phytochemical investigation of Aloe pulcherrima roots and evaluation for its antibacterial and antiplasmodial activities.

PubMed

Abdissa, Dele; Geleta, Girma; Bacha, Ketema; Abdissa, Negera

2017-01-01

Medicinal plants with documented traditional uses remain an important source for the treatment of a wide range of ailments. Evidence shows that majority of the Ethiopian population are still dependent on traditional medicine. Aloe pulcherrima Gilbert & Sebsebe is one of the endemic Aloe species traditionally used for the treatment of malaria and wound healing in central, Southern and Northern part of Ethiopia. The aim of the current study was, therefore, to isolate active compounds from roots of A. pulcherrima and evaluate for their antibacterial and antiplasmodial activities using standard test strains. Bioassay-guided sequential extraction and column chrom-atographic separation were employed for the isolation of bioactive pure compounds. The structures of the compounds were determined by 1D and 2D NMR spectro-scopic techniques. Disk diffusion method was employed to evaluate the antibacterial activities of the isolated compounds against four bacterial strains specifically (Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 27853). The malaria SYBR Green I-based in vitro assay technique was used for in vitro antiplasmodial activity evaluation of the compounds against chloroquine resistant (D6) and -sensitive (W2) strains of P. falciparum. Three compounds, chrysophanol, aloesaponarin I and aloesaponarin II were isolated from the acetone extracts of roots of A. pulcherrima. Evaluation of antibacterial activities revealed that aloesaponarin I and aloesaponarin II had significant activities against all the bacterial strains with inhibition zone diameters ranging from 18-27 mm as compared to the reference drug (gentamicin), which displayed inhibition zone diameter ranging between 20 mm (B. subtilis) and 25 mm (P. aeruginosa). The isolated compounds showed moderate in vitro antiplasmodial activity against both chloroquine resistant (W2) -sensitive (D6) strains. Isolation of chrysophanol, aloesaponarin I and aloesaponarin II from roots of A. pulcherrima is the first report of its kind. The finding could be used for further comprehensive evaluation of the isolated compounds for their antibacterial and antimalarial activities besides consideration of the same for potent drug development.

Expression of Clostridium acetobutylicum ATCC 824 Genes in Escherichia coli for Acetone Production and Acetate Detoxification

PubMed Central

Bermejo, Lourdes L.; Welker, Neil E.; Papoutsakis, Eleftherios T.

1998-01-01

A synthetic acetone operon (ace4) composed of four Clostridium acetobutylicum ATCC 824 genes (adc, ctfAB, and thl, coding for the acetoacetate decarboxylase, coenzyme A transferase, and thiolase, respectively) under the control of the thl promoter was constructed and was introduced into Escherichia coli on vector pACT. Acetone production demonstrated that ace4 is expressed in E. coli and resulted in the reduction of acetic acid levels in the fermentation broth. Since different E. coli strains vary significantly in their growth characteristics and acetate metabolism, ace4 was expressed in three E. coli strains: ER2275, ATCC 11303, and MC1060. Shake flask cultures of MC1060(pACT) produced ca. 2 mM acetone, while both strains ER2275(pACT) and ATCC 11303(pACT) produced ca. 40 mM acetone. Glucose-fed cultures of strain ATCC 11303(pACT) resulted in a 150% increase in acetone titers compared to those of batch shake flask cultures. External addition of sodium acetate to glucose-fed cultures of ATCC 11303(pACT) resulted in further increased acetone titers. In bioreactor studies, acidic conditions (pH 5.5 versus 6.5) improved acetone production. Despite the substantial acetone evaporation due to aeration and agitation in the bioreactor, 125 to 154 mM acetone accumulated in ATCC 11303(pACT) fermentations. These acetone titers are equal to or higher than those produced by wild-type C. acetobutylicum. This is the first study to demonstrate the ability to use clostridial genes in nonclostridial hosts for solvent production. In addition, acetone-producing E. coli strains may be useful hosts for recombinant protein production in that detrimental acetate accumulation can be avoided. PMID:9501448

[Analysis of DNA-DNA homologies in obligate methylotrophic bacteria].

PubMed

Doronina, N V; Govorukhina, N I; Lysenko, A M; Trotsenko, Iu A

1988-01-01

The genotypic affinity of 19 bacterial strains obligately dependent on methanol or methylamine as carbon and energy sources was studied by techniques of molecular DNA hybridization. The high homology level (35-88%) between motile strain Methylophilus methanolovorus V-1447D and nonmotile strain Methylobacillus sp. VSB-792 as well as other motile strains (Pseudomonas methanolica ATCC 21704, Methylomonas methanolica NRRL 5458, Pseudomonas sp. W6, strain A3) indicates that all of them belong to one genus. Rather high level of homology (62-63%) was found between Methylobacillus glycogenes ATCC 29475 and Pseudomonas insueta ATCC 21276 and strain G-10. The motile strain Methylophilus methylotrophus NCIB 10515 has a low homology (below 20%) to other of the studied obligate methylobacteria. Therefore, at least two genetically different genera of obligate methylobacteria can be distinguished, namely Methylophilus and Methylobacillus, the latter being represented by both motile and nonmotile forms.

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

PubMed

Abdelazez, Amro; Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao; Abdelmotaal, Heba; Sami, Rokayya; Meng, Xiang-Chen

2017-01-01

Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. ( Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture ( Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at -18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

PubMed Central

Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao

2017-01-01

Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at −18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only. PMID:28691028

Transcriptomic Analyses Elucidate Adaptive Differences of Closely Related Strains of Pseudomonas aeruginosa in Fuel

PubMed Central

Gunasekera, Thusitha S.; Bowen, Loryn L.; Zhou, Carol E.; Howard-Byerly, Susan C.; Foley, William S.; Striebich, Richard C.; Dugan, Larry C.

2017-01-01

ABSTRACT Pseudomonas aeruginosa can utilize hydrocarbons, but different strains have various degrees of adaptation despite their highly conserved genome. P. aeruginosa ATCC 33988 is highly adapted to hydrocarbons, while P. aeruginosa strain PAO1, a human pathogen, is less adapted and degrades jet fuel at a lower rate than does ATCC 33988. We investigated fuel-specific transcriptomic differences between these strains in order to ascertain the underlying mechanisms utilized by the adapted strain to proliferate in fuel. During growth in fuel, the genes related to alkane degradation, heat shock response, membrane proteins, efflux pumps, and several novel genes were upregulated in ATCC 33988. Overexpression of alk genes in PAO1 provided some improvement in growth, but it was not as robust as that of ATCC 33988, suggesting the role of other genes in adaptation. Expression of the function unknown gene PA5359 from ATCC 33988 in PAO1 increased the growth in fuel. Bioinformatic analysis revealed that PA5359 is a predicted lipoprotein with a conserved Yx(FWY)xxD motif, which is shared among bacterial adhesins. Overexpression of the putative resistance-nodulation-division (RND) efflux pump PA3521 to PA3523 increased the growth of the ATCC 33988 strain, suggesting a possible role in fuel tolerance. Interestingly, the PAO1 strain cannot utilize n-C8 and n-C10. The expression of green fluorescent protein (GFP) under the control of alkB promoters confirmed that alk gene promoter polymorphism affects the expression of alk genes. Promoter fusion assays further confirmed that the regulation of alk genes was different in the two strains. Protein sequence analysis showed low amino acid differences for many of the upregulated genes, further supporting transcriptional control as the main mechanism for enhanced adaptation. IMPORTANCE These results support that specific signal transduction, gene regulation, and coordination of multiple biological responses are required to improve the survival, growth, and metabolism of fuel in adapted strains. This study provides new insight into the mechanistic differences between strains and helpful information that may be applied in the improvement of bacterial strains for resistance to biotic and abiotic factors encountered during bioremediation and industrial biotechnological processes. PMID:28314727

Selective fermentation of pitted dates by S. cerevisiae for the production of concentrated fructose syrups and ethanol

NASA Astrophysics Data System (ADS)

Dharma Putra, Meilana; Abasaeed, Ahmed E.; Zeinelabdeen, Mohamed A.; Gaily, Mohamed H.; Sulieman, Ashraf K.

2014-04-01

About half of worldwide production of dates is unconsumed. Dates contain over 75 % reduced sugars (mostly glucose and fructose with nearly equal amount). Compared to the commercial Saccharomyces cerevisiae wild strain, the strains ATCC 36858 and 36859 could produce high concentration fructose syrups. The fructose fractions obtained were 95.9 and 97.4% for ATCC 36858 and 86.5 and 91.4% for ATCC 36859 at 30 and 33°C, respectively. Fructose yields higher than 90% were obtained using ATCC 36858 compared to those obtained using ATCC 36859 which were 87.3 and 66.1% at 30 and 33°C, respectively. The ethanol yield using ATCC 36858 was higher than that using ATCC 36859 by 16 and 9% at 30 and 33°C, respectively. Through this finding, the production of fructose and ethanol from date extract is a promising process. Moreover, the fructose fractions obtained here (about 90%) are much higher than those obtained with the commercial process, i.e. 55 % fructose syrups.

A Pseudomonas aeruginosa strain isolated from a contact lens-induced acute red eye (CLARE) is protease-deficient.

PubMed

Estrellas, P S; Alionte, L G; Hobden, J A

2000-03-01

Pseudomonas aeruginosa proteases are thought to be important virulence factors in the pathogenesis of corneal disease. This study examined protease production from two strains of P. aeruginosa responsible for two very distinct clinical diseases: strain Paer1, isolated from a Contact Lens-induced Acute Red Eye (CLARE), and strain KEI 1025, isolated from a corneal ulcer. Strains were compared to a laboratory strain (ATCC 19660) known to produce severe keratitis in experimentally infected mice for protease production and for ocular virulence. Protease production was examined with colorimetric assays, gelatin zymography and western blots. Elastase A activity was quantitated with a staphylolytic assay. Ocular virulence was examined using a mouse scratch model of keratitis. In contrast to strains KEI 1025 or ATCC 19660, Paer1 was unable to produce enzymatically active elastase A, elastase, and protease IV. All three strains produced active alkaline protease. Strains KEI 1025 and ATCC 19660 produced a fulminant keratitis in mice whereas Paer1 produced a mild transient infection. Restoration of elastase activity in Paer1 via genetic complementation did not result in a virulent phenotype. Co-infection of mouse eyes with strains Paer1 and ATCC 19660 resulted in the eventual loss of Paer1 from corneal tissue. These studies suggest that P. aeruginosa elastase A and/or protease IV, but not alkaline protease or elastase, contribute to the ocular virulence of this organism.

The mucin-degradation strategy of Ruminococcus gnavus: The importance of intramolecular trans-sialidases.

PubMed

Crost, Emmanuelle H; Tailford, Louise E; Monestier, Marie; Swarbreck, David; Henrissat, Bernard; Crossman, Lisa C; Juge, Nathalie

2016-07-03

We previously identified and characterized an intramolecular trans-sialidase (IT-sialidase) in the gut symbiont Ruminococcus gnavus ATCC 29149, which is associated to the ability of the strain to grow on mucins. In this work we have obtained and analyzed the draft genome sequence of another R. gnavus mucin-degrader, ATCC 35913, isolated from a healthy individual. Transcriptomics analyses of both ATCC 29149 and ATCC 35913 strains confirmed that the strategy utilized by R. gnavus for mucin-degradation is focused on the utilization of terminal mucin glycans. R. gnavus ATCC 35913 also encodes a predicted IT-sialidase and harbors a Nan cluster dedicated to sialic acid utilization. We showed that the Nan cluster was upregulated when the strains were grown in presence of mucin. In addition we demonstrated that both R. gnavus strains were able to grow on 2,7-anyhydro-Neu5Ac, the IT-sialidase transglycosylation product, as a sole carbon source. Taken together these data further support the hypothesis that IT-sialidase expressing gut microbes, provide commensal bacteria such as R. gnavus with a nutritional competitive advantage, by accessing and transforming a source of nutrient to their own benefit.

Antimicrobial activity of Carpolobia lutea extracts and fractions.

PubMed

Nwidu, Lucky L; Nwafor, Paul A; Vilegas, Wagner

2012-01-01

Carpolobia lutea (G. Don) (Polygalaceae) is a tropical medicinal plant putative in traditional medicines against gonorrhea, gingivitis, infertility, antiulcer and malaria. The present study evaluated the antimicrobial, antifungal and antihelicobacter effects of extracts C. lutea leaf, stem and root. The extracts were examined using the disc-diffusion and Microplates of 96 wells containing Muller-Hinton methods against some bacterial strains: Eschericia coli (ATCC 25922), E. coli (ATCC10418), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Staphyllococus aureus (ATCC 6571), Enterococcus faecalis (ATCC 29212) and Bacillus subtilis (NCTC 8853) and four clinical isolates: one fungi (Candida albican) and three bacteria (Salmonella, Sheigella and staphylococcus aureus). The Gram-positive bacteria: Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Bacillus subtilis (ATCC 19659) and the Gram-negative bacteria: Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Cândida albicans (ATCC 18804) and Helicobacter pylori (ATCC 43504). Some of these extracts were found to be active against some tested strains but activity against H. pylori was >1000mg/ml and good fungistatic activity against C. albican. The MIC against C. albican is in the order n-HF > CHF > ETF= EAF.The order of potency of fraction was the ethanol root > n-HF leaf > ethanol fraction stem > chloroform fraction leaf = ethyl acetate fraction leaf. Polyphenols were demonstrated in ethanol fraction, ethyl acetate fraction, crude ethyl acetate extract and ethanol extract, respectively. These polyphenols isolated may partly explain and support the use of C. lutea for the treatment of infectious diseases in traditional Ibibio medicine of Nigeria.

Fabrication, characterization and in vitro profile based interaction with eukaryotic and prokaryotic cells of alginate-chitosan-silica biocomposite.

PubMed

Balaure, Paul Catalin; Andronescu, Ecaterina; Grumezescu, Alexandru Mihai; Ficai, Anton; Huang, Keng-Shiang; Yang, Chih-Hui; Chifiriuc, Carmen Mariana; Lin, Yung-Sheng

2013-01-30

This work is focused on the fabrication of a new drug delivery system based on polyanionic matrix (e.g. sodium alginate), polycationic matrix (e.g. chitosan) and silica network. The FT-IR, SEM, DTA-TG, eukaryotic cell cycle and viability, and in vitro assay of the influence of the biocomposite on the efficacy of antibiotic drugs were investigated. The obtained results demonstrated the biocompatibility and the ability of the fabricated biocomposite to maintain or improve the efficacy of the following antibiotics: piperacillin-tazobactam, cefepime, piperacillin, imipenem, gentamicin, ceftazidime against Pseudomonas aeruginosa ATCC 27853 and cefazolin, cefaclor, cefuroxime, ceftriaxone, cefoxitin, trimethoprim/sulfamethoxazole against Escherichia coli ATCC 25922 reference strains. Copyright © 2012 Elsevier B.V. All rights reserved.

Identification and screening of rare actinomycetes isolated from Neesia altissima Bl.

NASA Astrophysics Data System (ADS)

Pratiwi, R. H.; Hidayat, I.; Hanafi, M.; Mangunwardoyo, W.

2017-07-01

Actinomycetes is the main source of antibiotics and endophytic actinomycetes from medicinal plants has considerable potential as like the host. The aim of this research is to identify rare actinomycetes isolated from Neesia altissima and to screen their antagonistic activity against diarrhea-causing bacteria in order to find new potential secondary metabolites. Samples of N. altissima were collected from mount Halimun-Salak National Park. Endophytic actinomycetes were isolated from roots of N. altissima by surface sterilization method. Screening of antagonistic activity was conducted against five diarrhea-causing bacteria such as Bacillus cereus ATCC 10876, Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 25241, Shigella flexneri ATCC 12022, and Staphylococcus aureus ATCC 25923 by using diffusion disc methods. The endophytic actinomycete showed in vitro antibacterial activity against four diarrhea-causing bacteria, except the B. cereus ATCC 10876. The phylogenetic tree generated from 16S rRNA sequence showed that sequence of endophytic actinomycetes isolates nested in the clade belonging to the genus Nonomuraea. Sequence of UICC B-94 formed a monophyletic clade with N. jabiensis strain A4036 and N. rubra strain AC 615. Therefore, it is named as Nonomuraea sp. strain UICC B-94.

Physico-chemical analysis and antimicrobial potential of Apis dorsata, Apis mellifera and Ziziphus jujube honey samples from Pakistan

PubMed Central

Fahim, Hira; Dasti, Javid Iqbal; Ali, Ihsan; Ahmed, Safia; Nadeem, Muhammad

2014-01-01

Objective To evaluate physico-chemical properties and antimicrobial potential of indigenous honey samples against different reference strains including Escherichia coli ATCC 8739, Enterobacter aerogenes ATCC 13048, Pseudomonas aeroginosa ATCC 9027, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, Salmonella typhi ATCC 14028, Klebsiella pneumonia ATCC 13883, Aspergillus niger ATCC 16404, Rhizopus oligosporus PCSIR1, Candida albicans ATCC 14053 and Candida utilis ATCC 9950. Methods By using standard methods samples were evaluated for their antimicrobial properties including additive effect of starch and non-peroxidase activity, antioxidative properties (phenol contents, flavonoid contents, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity). Prior to this evaluation, complete physico-chemical properties including pH, color, ash contents, protein contents, moisture contents, hydroxymethyl furfural contents, total sugar contents, reducing sugar and non-reducing sugar contents were analyzed. Results Relatively higher ash contents were found in the Siddar honey i.e. (0.590 0±0.033 6)% and small honey showed relatively higher protein contents i.e. (777.598±9.880) mg/kg. The moisture contents of tested honey samples ranged between 13.8%-16.6%, total sugar contents from 61.672%-72.420% and non-reducing sugar contents from 1.95%-3.93%. Presences of phenolic contents indicate higher antioxidant potential of these honey samples. All bacteria showed clear inhibition zones in response to tested honey samples whereas fungi and yeast showed inhibition at higher concentrations of these honey samples. For Escherichia coli, Bacillus subtilis, Salmonella typhi, Pseudomonas aeroginosa and Aspergillus niger, overall the small honey showed the higher activity than other honey samples. Conclusion Physico-chemical analysis of honey samples confirmed good quality of honey according to the standards set by European Union Commission and Codex Alimentarius Commission. Evaluation of these honey samples confirms antimicrobial potential of particular types of honeys indigenous to Pakistan. PMID:25183333

Draft Genome Sequence of Lactobacillus helveticus ATCC 12046

PubMed Central

2018-01-01

ABSTRACT Lactobacillus helveticus is a lactic acid bacterium used traditionally in the dairy industry, especially in the manufacture of cheeses. We present here the 2,141,841-bp draft genome sequence of L. helveticus strain ATCC 12046, a potential starter strain for improving cheese production. PMID:29449405

Susceptibility of Oral Bacteria to an Antimicrobial Decapeptide

DTIC Science & Technology

2003-01-01

coccus mitis ATCC 15913, Streptococcus oralis ATCC 35037T, Lactoba- cillus salivarius ATCC 29602, Lactobacillus acidophilus ATCC 43571 and...exhibited an ED99 (the dose at which 99% killing was observed after 15 min at 37 8C) of 6.25 gml1 against selected strains of Lactobacillus salivarius...broth microdilution assay. Growth of the cariogenic bacteria S.mutansATCC 25175T, S. sobrinus and L. acidophilus was also inhibited effectively by Fig

Burkholderia paludis sp. nov., an Antibiotic-Siderophore Producing Novel Burkholderia cepacia Complex Species, Isolated from Malaysian Tropical Peat Swamp Soil.

PubMed

Ong, Kuan Shion; Aw, Yoong Kit; Lee, Learn Han; Yule, Catherine M; Cheow, Yuen Lin; Lee, Sui Mae

2016-01-01

A novel Gram negative rod-shaped bacterium, designated strain MSh1 T , was isolated from Southeast Pahang tropical peat swamp forest soil in Malaysia and characterized using a polyphasic taxonomy approach. The predominant cellular fatty acids (>10.0%) were C 16:0 (31.7%), C 17:0 cyclo (26.6%), and C 19:0 cyclo ω8c (16.1%). The polar lipids detected were phosphatidylglycerol, phosphatidylethanolamine, and diphosphatidylglycerol. The predominant ubiquinone was Q-8. This revealed that strain MSh1 T belongs to the genus Burkholderia . The type strain MSh1 T can be differentiated from other Burkholderia cepacia complex (Bcc) species by phylogenetic analysis of 16S rRNA gene sequence, multilocus sequence analysis (MLSA), average nucleotide identity (ANI) and biochemical tests. DNA-DNA relatedness values between strain MSh1 T and closely related type strains were below the 70% threshold value. Based on this polyphasic study of MSh1 T , it can be concluded that this strain represents a novel species within the Bcc, for which the name Burkholderia paludis sp. nov. is proposed. The type strain is MSh1 T (= DSM 100703 T = MCCC 1K01245 T ). The dichloromethane extract of MSh1 T exhibited antimicrobial activity against four Gram positive bacteria ( Enterococcus faecalis ATCC 29212, E. faecalis ATCC 700802, Staphylococcus aureus ATCC 29213, S. aureus ATCC 700699) and a Gram negative bacteria ( Escherichia coli ATCC 25922). Further purification work has led to the isolation of Compound 1, pyochelin. Pyochelin demonstrated antimicrobial activity against four S. aureus strains and three E . faecalis strains with MIC-values of 3.13 μg/ml and 6.26 μg/ml, respectively. SEM analysis showed that the cellular morphology of E. faecalis ATCC 700802 was not affected by pyochelin; suggesting that it might target the intracellular components. Pyochelin, a siderophore with antimicrobial activity might be useful in treating bacterial infections caused by S. aureus and E. faecalis , however further work has to be done.

Complete genome sequence of the plant pathogen Erwinia amylovora strain ATCC 49946

USDA-ARS?s Scientific Manuscript database

Erwinia amylovora causes the economically important disease fire blight that affects rosaceous plants, especially pear and apple. Here we report the complete genome sequence and annotation of strain ATCC 49946. The analysis of the sequence and its comparison with sequenced genomes of closely related...

Draft Genome Sequence of Lactobacillus helveticus ATCC 12046.

PubMed

Palomino, María Mercedes; Burguener, Germán F; Campos, Josefina; Allievi, Mariana; Fina-Martin, Joaquina; Prado Acosta, Mariano; Fernández Do Porto, Darío A; Ruzal, Sandra M

2018-02-15

Lactobacillus helveticus is a lactic acid bacterium used traditionally in the dairy industry, especially in the manufacture of cheeses. We present here the 2,141,841-bp draft genome sequence of L. helveticus strain ATCC 12046, a potential starter strain for improving cheese production. Copyright © 2018 Palomino et al.

Antibacterial activity of Citrus limonum fruit juice extract.

PubMed

Okeke, Malachy Ifeanyi; Okoli, Arinze Stanley; Eze, Edith Nneka; Ekwume, Grace Chinwe; Okosa, Evangelin Uchena; Iroegbu, Christian Ukwuoma

2015-09-01

The fruit juice extract of Citrus limonum was investigated for antibacterial activity. The antibacterial activity of the extract on ten strains of bacteria was determined by both agar well diffusion and macro-broth dilution methods. The extract was variously bacteriostatic and bactericidal against Bacillussubtilis ATCC 6051, Staphylococcus aureus ATCC 12600, Escherichia coli ATCC 11775, Pseudomonas aeruginosa ATCC 10145 as well as locally isolated clinical strains of the above bacteria and Salmonella kintambo (Human: 13, 23: mt:-), Salmonella typhi and Proteus sp. The MICs ranged from 0.78 mg/ml to 50mg/ml; MBCs, 25.0mg/ml to >100mg/ml and MBC/MIC ratios 2.0 to >16.0. These results provide scientific justification for the medicinal use of Citrus limonum fruit juice by Nigerian herbalists in the treatment of diseases in which strains of the test organisms have been implicated as etiologic agents.

Identification of salivary Lactobacillus rhamnosus species by DNA profiling and a specific probe.

PubMed

Richard, B; Groisillier, A; Badet, C; Dorignac, G; Lonvaud-Funel, A

2001-03-01

The Lactobacillus genus has been shown to be associated with the dental carious process, but little is known about the species related to the decay, although Lactobacillus rhamnosus is suspected to be the most implicated species. Conventional identification methods based on biochemical criteria lead to ambiguous results, since the Lactobacillus species found in saliva are phenotypically close. To clarify the role of this genus in the evolution of carious disease, this work aimed to find a rapid and reliable method for identifying the L. rhamnosus species. Methods based on hybridization with DNA probes and DNA amplification by PCR were used. The dominant salivary Lactobacillus species (reference strains from the ATCC) were selected for this purpose as well as some wild strains isolated from children's saliva. DNA profiling using semirandom polymorphic DNA amplification (semi-RAPD) generated specific patterns for L. rhamnosus ATCC 7469. The profiles of all L. rhamnosus strains tested were similar and could be grouped; these strains shared four common fragments. Wild strains first identified with classic methods shared common patterns with the L. rhamnosus species and could be reclassified. One fragment of the profile was purified, cloned, used as a probe and found to be specific to the L. rhamnosus species. These results may help to localize this species within its ecological niche and to elucidate the progression of the carious process.

Disruption of methicillin-resistant Staphylococcus aureus protein synthesis by tannins

PubMed Central

Adnan, Siti-Noor-Adnalizawati; Ibrahim, Nazlina; Yaacob, Wan Ahmad

2017-01-01

Introduction Methicillin-resistant Staphylococcus aureus (MRSA) is a worldwide public health threat, displaying multiple antibiotic resistance that causes morbidity and mortality. Management of multidrug-resistant (MDR) MRSA infections is extremely difficult due to their inherent resistance to currently used antibiotics. New antibiotics are needed to combat the emergence of antimicrobial resistance. Methods The in vitro effect of tannins was studied against MRSA reference strain (ATCC 43300) and MRSA clinical strains utilizing antimicrobial assays in conjunction with both scanning and transmission electron microscopy. To reveal the influence of tannins in MRSA protein synthesis disruption, we utilized next-generation sequencing (NGS) to provide further insight into the novel protein synthesis transcriptional response of MRSA exposed to these compounds. Results Tannins possessed both bacteriostatic and bactericidal activity with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of 0.78 and 1.56 mg/mL, respectively, against all tested MRSA. Scanning and transmission electron microscopy of MRSA treated with tannins showed decrease in cellular volume, indicating disruption of protein synthesis. Conclusion Analysis of a genome-wide transcriptional profile of the reference strain ATCC 43300 MRSA in response to tannins has led to the finding that tannins induced significant modulation in essential ribosome pathways, which caused a reduction in the translation processes that lead to inhibition of protein synthesis and obviation of bacterial growth. These findings highlight the potential of tannins as new promising anti-MRSA agents in clinical application such as body wash and topical cream or ointments. PMID:29264356

Synthesis, antimicrobial evaluation and theoretical prediction of NMR chemical shifts of thiazole and selenazole derivatives with high antifungal activity against Candida spp.

NASA Astrophysics Data System (ADS)

Łączkowski, Krzysztof Z.; Motylewska, Katarzyna; Baranowska-Łączkowska, Angelika; Biernasiuk, Anna; Misiura, Konrad; Malm, Anna; Fernández, Berta

2016-03-01

Synthesis and investigation of antimicrobial activities of novel thiazoles and selenazoles is presented. Their structures were determined using NMR, FAB(+)-MS, HRMS and elemental analyses. To support the experiment, theoretical calculations of the 1H NMR shifts were carried out for representative systems within the DFT B3LYP/6-311++G** approximation which additionally confirmed the structure of investigated compounds. Among the derivatives, compounds 4b, 4h, 4j and 4l had very strong activity against reference strains of Candida albicans ATCC and Candida parapsilosis ATCC 22019 with MIC = 0.49-7.81 μg/ml. In the case of compounds 4b, 4c, 4h - 4j and 4l, the activity was very strong against of Candida spp. isolated from clinical materials, i.e. C. albicans, Candida krusei, Candida inconspicua, Candida famata, Candida lusitaniae, Candida sake, C. parapsilosis and Candida dubliniensis with MIC = 0.24-15.62 μg/ml. The activity of several of these was similar to the activity of commonly used antifungal agent fluconazole. Additionally, compounds 4m - 4s were found to be active against Gram-positive bacteria, both pathogenic staphylococci Staphylococcus aureus ATCC with MIC = 31.25-125 μg/ml and opportunistic bacteria, such as Staphylococcus epidermidis ATCC 12228 and Micrococcus luteus ATCC 10240 with MIC = 7.81-31.25 μg/ml.

Transcriptomic Analyses Elucidate Adaptive Differences of Closely Related Strains of Pseudomonas aeruginosa in Fuel.

PubMed

Gunasekera, Thusitha S; Bowen, Loryn L; Zhou, Carol E; Howard-Byerly, Susan C; Foley, William S; Striebich, Richard C; Dugan, Larry C; Ruiz, Oscar N

2017-05-15

Pseudomonas aeruginosa can utilize hydrocarbons, but different strains have various degrees of adaptation despite their highly conserved genome. P. aeruginosa ATCC 33988 is highly adapted to hydrocarbons, while P. aeruginosa strain PAO1, a human pathogen, is less adapted and degrades jet fuel at a lower rate than does ATCC 33988. We investigated fuel-specific transcriptomic differences between these strains in order to ascertain the underlying mechanisms utilized by the adapted strain to proliferate in fuel. During growth in fuel, the genes related to alkane degradation, heat shock response, membrane proteins, efflux pumps, and several novel genes were upregulated in ATCC 33988. Overexpression of alk genes in PAO1 provided some improvement in growth, but it was not as robust as that of ATCC 33988, suggesting the role of other genes in adaptation. Expression of the function unknown gene PA5359 from ATCC 33988 in PAO1 increased the growth in fuel. Bioinformatic analysis revealed that PA5359 is a predicted lipoprotein with a conserved Yx(FWY)xxD motif, which is shared among bacterial adhesins. Overexpression of the putative resistance-nodulation-division (RND) efflux pump PA3521 to PA3523 increased the growth of the ATCC 33988 strain, suggesting a possible role in fuel tolerance. Interestingly, the PAO1 strain cannot utilize n -C 8 and n -C 10 The expression of green fluorescent protein (GFP) under the control of alkB promoters confirmed that alk gene promoter polymorphism affects the expression of alk genes. Promoter fusion assays further confirmed that the regulation of alk genes was different in the two strains. Protein sequence analysis showed low amino acid differences for many of the upregulated genes, further supporting transcriptional control as the main mechanism for enhanced adaptation. IMPORTANCE These results support that specific signal transduction, gene regulation, and coordination of multiple biological responses are required to improve the survival, growth, and metabolism of fuel in adapted strains. This study provides new insight into the mechanistic differences between strains and helpful information that may be applied in the improvement of bacterial strains for resistance to biotic and abiotic factors encountered during bioremediation and industrial biotechnological processes. Copyright © 2017 American Society for Microbiology.

Finished Genome Sequence of Escherichia coli K-12 Strain HMS174 (ATCC 47011).

PubMed

Mairhofer, Juergen; Krempl, Peter M; Thallinger, Gerhard G; Striedner, Gerald

2014-11-20

Escherichia coli strain K-12 substrain HMS174 is an engineered descendant of the E. coli K-12 wild-type strain. Like its ancestor, it is an important organism in biotechnological research and is used in fermentation processes for heterologous protein production. Here, we report the complete genome sequence of E. coli HMS174 (ATCC 47011). Copyright © 2014 Mairhofer et al.

Classification of Nonomuraea sp. ATCC 39727, an actinomycete that produces the glycopeptide antibiotic A40926, as Nonomuraea gerenzanensis sp. nov.

PubMed

Dalmastri, Claudia; Gastaldo, Luciano; Marcone, Giorgia Letizia; Binda, Elisa; Congiu, Terenzio; Marinelli, Flavia

2016-02-01

Strain ATCC 39727, which produces the antibiotic A40926 (the natural precursor of the antibiotic dalbavancin), was isolated from a soil sample collected in India, and it was originally classified as a member of the genus Actinomadura on the base of morphology and cell-wall composition. A phylogenetic analysis based on 16S rRNA gene sequences indicates that the strain forms a distinct clade within the genus Nonomuraea, and it is most closely related to Nonomuraea angiospora DSM 43173T (98.72 % similarity) and Nonomuraea jabiensis A4036T (98.69 %). The strain forms an extensively branched substrate mycelium and aerial hyphae that form spiral chains of spores with ridged surfaces. The cell wall contains meso-diaminopimelic acid and the whole-cell sugars are glucose, ribose, galactose, mannose and madurose (madurose as the diagnostic sugar). The N-acyl type of muramic acid is acetyl. The predominant menaquinone is MK-9(H4), with minor amounts of MK-9(H2), MK-9(H6) and MK-9(H0). The polar-lipid profile includes diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylmethylethanolamine, hydroxyphosphatidylmethylethanolamine, phosphatidylinositol and a series of uncharacterized phospholipids, glycolipids and phosphoglycolipids. The major cellular fatty acids are iso-C16 : 0 and 10-methyl C17 : 0. The genomic DNA G+C content is 71.2 mol%. Significant differences in the morphological, chemotaxonomic and biochemical data, together with DNA-DNA relatedness between strain ATCC 39727 and closely related type strains, clearly demonstrated that strain ATCC 39727 represents a novel species of the genus Nonomuraea, for which the name Nonomuraea gerenzanensis sp. nov. is proposed. The type strain is ATCC 39727T ( = DSM 100948T).

Bifidobacterium animalis subsp. lactis ATCC 27673 Is a Genomically Unique Strain within Its Conserved Subspecies

PubMed Central

Loquasto, Joseph R.; Barrangou, Rodolphe; Dudley, Edward G.; Stahl, Buffy; Chen, Chun

2013-01-01

Many strains of Bifidobacterium animalis subsp. lactis are considered health-promoting probiotic microorganisms and are commonly formulated into fermented dairy foods. Analyses of previously sequenced genomes of B. animalis subsp. lactis have revealed little genetic diversity, suggesting that it is a monomorphic subspecies. However, during a multilocus sequence typing survey of Bifidobacterium, it was revealed that B. animalis subsp. lactis ATCC 27673 gave a profile distinct from that of the other strains of the subspecies. As part of an ongoing study designed to understand the genetic diversity of this subspecies, the genome of this strain was sequenced and compared to other sequenced genomes of B. animalis subsp. lactis and B. animalis subsp. animalis. The complete genome of ATCC 27673 was 1,963,012 bp, contained 1,616 genes and 4 rRNA operons, and had a G+C content of 61.55%. Comparative analyses revealed that the genome of ATCC 27673 contained six distinct genomic islands encoding 83 open reading frames not found in other strains of the same subspecies. In four islands, either phage or mobile genetic elements were identified. In island 6, a novel clustered regularly interspaced short palindromic repeat (CRISPR) locus which contained 81 unique spacers was identified. This type I-E CRISPR-cas system differs from the type I-C systems previously identified in this subspecies, representing the first identification of a different system in B. animalis subsp. lactis. This study revealed that ATCC 27673 is a strain of B. animalis subsp. lactis with novel genetic content and suggests that the lack of genetic variability observed is likely due to the repeated sequencing of a limited number of widely distributed commercial strains. PMID:23995933

Roseomonas elaeocarpi sp. nov., isolated from olive (Elaeocarpus hygrophilus Kurz.) phyllosphere.

PubMed

Damtab, Jenjira; Nutaratat, Pumin; Boontham, Wanatchaporn; Srisuk, Nantana; Duangmal, Kannika; Yurimoto, Hiroya; Sakai, Yasuyoshi; Muramatsu, Yuki; Nakagawa, Yasuyoshi

2016-01-01

An aerobic, Gram-stain-negative, coccobacillus-shaped, non-endospore-forming, pink-pigmented bacterium, designated PN2T, was isolated from an olive leaf. The strain grew at 15-35 °C with an optimum temperature for growth at 30 °C, and at pH 5.0-7.5 with an optimum pH for growth at 6.0. Growth was observed in the presence of up to 1.02 % (w/v) NaCl. The major fatty acids were C19 : 0 cyclo ω8c, C16 : 0 and C18 : 1ω7c. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, unknown aminolipids, an unknown phospholipid and an unknown lipid. The respiratory quinone was ubiquinone-10. The DNA G+C content of strain PN2T was 70.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain PN2T was closely related to members of the genus Roseomonas and shared highest similarity with Roseomonas mucosa ATCC BAA-692T (96.5 %), Roseomonas gilardii subsp. gilardii ATCC 49956T (96.2 %) and Roseomonas gilardii subsp. rosea ATCC BAA-691T (96.2 %). Furthermore, the DNA-DNA relatedness value between strain PN2T and the closest related species R. mucosa ATCC BAA-692T was 27 %. These data allowed the phenotypic and genotypic differentiation of strain PN2T from its closest phylogenetic neighbour (R. mucosa ATCC BAA-692T). Based on phenotypic and genotypic characteristics, strain PN2T is classified as representing a novel species of the genus Roseomonas for which the name Roseomonas elaeocarpi sp. nov. is proposed. The type strain is PN2T ( = BCC 44864T = NBRC 107871T).

Nitrosomonas communis strain YNSRA, an ammonia-oxidizing bacterium, isolated from the reed rhizoplane in an aquaponics plant.

PubMed

Tokuyama, Tatsuaki; Mine, Atsusi; Kamiyama, Kaoru; Yabe, Ryuichi; Satoh, Kazuo; Matsumoto, Hirotoshi; Takahashi, Reiji; Itonaga, Koji

2004-01-01

An ammonia-oxidizing bacterium (strain YNSRA) was isolated from the rhizoplane of the reed (Phragmites communis) used in an aquaponics plant which is a wastewater treatment plant. Strain YNSRA was identified as Nitrosomonas communis by taxonomic studies. The hydroxylamine-cytochrome c reductase (HCR) of strain YNSRA was found to have a higher activity (25.60 u/mg) than that of Nitrosomonas europaea ATCC25978T (8.94 u/mg). Ribulose-1,5-bisphosphate carboxylase (RubisCO) activity was detected at very low levels in strain YNSRA, whereas strain ATCC25978T had definite activity.

Mutant strain of C. acetobutylicum and process for making butanol

DOEpatents

Jain, Mahendra K.; Beacom, Daniel; Datta, Rathin

1993-01-01

A biologically pure asporogenic mutant of Clostridium acetobutylicum is produced by growing sporogenic C. acetobutylicum ATCC 4259 and treating the parent strain with ethane methane sulfonate. The mutant which as been designated C. acetobutylicum ATCC 55025 is useful in an improved ABE fermentation process, and produces high concentrations of butanol and total solvents.

Pseudomonas aeruginosa Trent and zinc homeostasis.

PubMed

Davies, Corey B; Harrison, Mark D; Huygens, Flavia

2017-09-01

Pseudomonas aeruginosa is a Gram-negative pathogen and the major cause of mortality in patients with cystic fibrosis. The mechanisms that P. aeruginosa strains use to regulate intracellular zinc have an effect on infection, antibiotic resistance and the propensity to form biofilms. However, zinc homeostasis in P. aeruginosa strains of variable infectivity has not been compared. In this study, zinc homeostasis in P. aeruginosa Trent, a highly infectious clinical strain, was compared to that of a laboratory P. aeruginosa strain, ATCC27853. Trent was able to tolerate higher concentrations of additional zinc in rich media than ATCC27853. Further, pre-adaptation to additional zinc enhanced the growth of Trent at non-inhibitory concentrations but the impact of pre-adaption on the growth of ATCC27853 under the same conditions was minimal. The results establish clear differences in zinc-induced responses in Trent and ATCC27853, and how zinc homeostasis can be a promising target for the development of novel antimicrobial strategies for P. aeruginosa infection in cystic fibrosis patients. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Synthesis and antimycobacterial activity of isoniazid derivatives from renewable fatty acids.

PubMed

Rodrigues, Marieli O; Cantos, Jéssica B; D'Oca, Caroline R Montes; Soares, Karina L; Coelho, Tatiane S; Piovesan, Luciana A; Russowsky, Dennis; da Silva, Pedro A; D'Oca, Marcelo G Montes

2013-11-15

This work describes the synthesis of a series of fatty acid hydrazide derivatives of isoniazid (INH). The compounds were tested against Mycobacterium tuberculosis H37Rv (ATCC 27294) as well as INH-resistant (ATCC 35822 and 1896 HF) and rifampicin-resistant (ATCC 35338) M. tuberculosis strains. The fatty acid derivatives of INH showed high antimycobacterial potency against the studied strains, which is desirable for a pharmaceutical compound, suggesting that the increased lipophilicity of isoniazid plays an important role in its antimycobacterial activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Discrimination of probiotic Lactobacillus strains for poultry by repetitive sequenced-based PCR fingerprinting.

PubMed

Lee, Chin Mei; Sieo, Chin Chin; Cheah, Yoke-Kqueen; Abdullah, Norhani; Ho, Yin Wan

2012-02-01

Four repetitive element sequence-based polymerase chain reaction (rep-PCR) methods, namely repetitive extragenic palindromic PCR (REP-PCR), enterobacterial repetitive intergenic consensus PCR (ERIC-PCR), polytrinucleotide (GTG)₅ -PCR and BOX-PCR, were evaluated for the molecular differentiation of 12 probiotic Lactobacillus strains previously isolated from the gastrointestinal tract of chickens and used as a multistrain probiotic. This study represents the first analysis of the comparative efficacy of these four rep-PCR methods and their combination (composite rep-PCR) in the molecular typing of Lactobacillus strains based on a discriminatory index (D). Species-specific and strain-specific profiles were observed from rep-PCR. From the numerical analysis of composite rep-PCR, BOX-PCR, (GTG)₅ -PCR, REP-PCR and ERIC-PCR, D values of 0.9118, 0.9044, 0.8897, 0.8750 and 0.8529 respectively were obtained. Composite rep-PCR analysis was the most discriminative method, with eight Lactobacillus strains, namely L. brevis ATCC 14869(T) , L. reuteri C 10, L. reuteri ATCC 23272(T) , L. gallinarum ATCC 33199(T) , L. salivarius ATCC 11741(T) , L. salivarius I 24, L. panis JCM 11053(T) and L. panis C 17, being differentiated at the strain level. Composite rep-PCR analysis is potentially a useful fingerprinting method to discriminate probiotic Lactobacillus strains isolated from the gastrointestinal tract of chickens. Copyright © 2011 Society of Chemical Industry.

Effect of the Biofilm Age and Starvation on Acid Tolerance of Biofilm Formed by Streptococcus mutans Isolated from Caries-Active and Caries-Free Adults.

PubMed

Jiang, Shan; Chen, Shuai; Zhang, Chengfei; Zhao, Xingfu; Huang, Xiaojing; Cai, Zhiyu

2017-03-30

Streptococcus mutans ( S. mutans ) is considered a leading cause of dental caries. The capability of S. mutans to tolerate low pH is essential for its cariogenicity. Aciduricity of S. mutans is linked to its adaptation to environmental stress in oral cavity. This study aimed to investigate the effect of biofilm age and starvation condition on acid tolerance of biofilm formed by S. mutans clinical isolates. S. mutans clinical strains isolated from caries-active (SM593) and caries-free (SM18) adults and a reference strain (ATCC25175) were used for biofilm formation. (1) Both young and mature biofilms were formed and then exposed to pH 3.0 for 30 min with (acid-adapted group) or without (non-adapted group) pre-exposure to pH 5.5 for three hours. (2) The mature biofilms were cultured with phosphate-buffered saline (PBS) (starved group) or TPY (polypeptone-yeast extract) medium (non-starved group) at pH 7.0 for 24 h and then immersed in medium of pH 3.0 for 30 min. Biofilms were analyzed through viability staining and confocal laser scanning microscopy. In all three strains, mature, acid-adapted and starved biofilms showed significantly less destructive structure and more viable bacteria after acid shock than young, non-adapted and non-starved biofilms, respectively (all p < 0.05). Furthermore, in each condition, SM593 biofilm was denser, with a significantly larger number of viable bacteria than that of SM18 and ATCC25175 (all p < 0.05). Findings demonstrated that mature, acid-adapted and starvation might protect biofilms of all three S. mutans strains against acid shock. Additionally, SM593 exhibited greater aciduricity compared to SM18 and ATCC25175, which indicated that the colonization of high cariogenicity of clinical strains may lead to high caries risk in individuals.

Contact lens disinfecting solutions antibacterial efficacy: comparison between clinical isolates and the standard ISO ATCC strains of Pseudomonas aeruginosa and Staphylococcus aureus.

PubMed

Mohammadinia, M; Rahmani, S; Eslami, G; Ghassemi-Broumand, M; Aghazadh Amiri, M; Aghaie, Gh; Tabatabaee, S M; Taheri, S; Behgozin, A

2012-02-01

To evaluate the disinfectant properties of the three multipurpose contact lens disinfecting solutions available in Iran, against clinical isolates and the standard ISO ATCC strains of Pseudomonas aeruginosa and Staphylococcus aureus, based on the international organization for standardization (ISO) 14729 guidelines. Three multipurpose solutions that were tested were ReNu Multiplus, Solo Care Aqua and All-Clean Soft. The test solutions were challenged with clinical isolates and the standard strains of P. aeruginosa(ATCC 9027) and S. aureus(ATCC 6538), based on the ISO Stand-alone procedure for disinfecting products. Solutions were sampled for surviving microorganisms at manufacturer's minimum recommended disinfection time. The number of viable organisms was determined and log reductions calculated. All of the three test solutions in this study provided a reduction greater than the required mean 3.0 logarithmic reduction against the recommended standard ATCC strains of P. aeruginosa and S. aureus. Antibacterial effectiveness of Solo Care Aqua and All-Clean Soft against clinical isolates of P. aeruginosa and S. aureus were acceptable based on ISO 14729 Stand-alone test. ReNu MultiPlus showed a minimum acceptable efficacy against the clinical isolate of S. aureus, but did not reduce the clinical isolate by the same amount. Although the contact lens disinfecting solutions meet/exceed the ISO 14729 Stand-alone primary acceptance criteria for standard strains of P. aeruginosa and S. aureus, their efficacy may be insufficient against clinical isolates of these organisms.

Contact lens disinfecting solutions antibacterial efficacy: comparison between clinical isolates and the standard ISO ATCC strains of Pseudomonas aeruginosa and Staphylococcus aureus

PubMed Central

Mohammadinia, M; Rahmani, S; Eslami, G; Ghassemi-Broumand, M; Aghazadh Amiri, M; Aghaie, Gh; Tabatabaee, S M; Taheri, S; Behgozin, A

2012-01-01

Purpose To evaluate the disinfectant properties of the three multipurpose contact lens disinfecting solutions available in Iran, against clinical isolates and the standard ISO ATCC strains of Pseudomonas aeruginosaand Staphylococcus aureus, based on the international organization for standardization (ISO) 14729 guidelines. Methods Three multipurpose solutions that were tested were ReNu Multiplus, Solo Care Aqua and All-Clean Soft. The test solutions were challenged with clinical isolates and the standard strains of P. aeruginosa(ATCC 9027) and S. aureus(ATCC 6538), based on the ISO Stand-alone procedure for disinfecting products. Solutions were sampled for surviving microorganisms at manufacturer's minimum recommended disinfection time. The number of viable organisms was determined and log reductions calculated. Results All of the three test solutions in this study provided a reduction greater than the required mean 3.0 logarithmic reduction against the recommended standard ATCC strains of P. aeruginosaand S. aureus. Antibacterial effectiveness of Solo Care Aqua and All-Clean Soft against clinical isolates of P. aeruginosaand S. aureuswere acceptable based on ISO 14729 Stand-alone test. ReNu MultiPlus showed a minimum acceptable efficacy against the clinical isolate of S. aureus, but did not reduce the clinical isolate by the same amount. Conclusions Although the contact lens disinfecting solutions meet/exceed the ISO 14729 Stand-alone primary acceptance criteria for standard strains of P. aeruginosaand S. aureus, their efficacy may be insufficient against clinical isolates of these organisms. PMID:22094301

Experimental and In-Silico Investigation of Anti-Microbial Activity of 1-Chloro-2-Isocyanatoethane Derivatives of Thiomorpholine, Piperazine and Morpholine.

PubMed

Nwuche, Charles O; Ujam, Oguejiofo T; Ibezim, Akachukwu; Ujam, Ifeoma B

2017-01-01

The Antibiogram properties of 1-chloro-2-isocyanatoethane derivatives of thiomorpholine (CTC), piperazine (CPC) and morpholine (CMC) were evaluated by the approved agar well diffusion, the minimum inhibitory concentration (MIC) and in silico techniques. A total of fourteen microbial cultures consisting of ten bacteria and four yeast strains were used in the biological study while affinity of the compounds for DNA gyrase, a validated antibacterial drug target, was investigated by docking method. Results indicate that both thiomorpholine and piperazine had zero activity against the Gram negative organisms tested. With morpholine, similar result was obtained except that cultures of Escherichia coli (ATCC 15442) and Salmonella typhi (ATCC 6539) presented with weak sensitivity (7-8 mm) as shown by the inhibition zone diameter (IZD) measurement. The Gram positive organisms were more sensitive to morpholine than the other compounds. The highest IZD values of 15-18 mm were achieved except for Streptococcus pneumoniae (ATCC 49619) in which mobility of the compound stopped after 12 mm. S. pneumoniae was resistant to both thiomorpholine and piperazine. The yeast strains were not sensitive to any of the studied compounds investigated. The MIC tests evaluated against a reference antibiotic show that while morpholine was most active at 4 μg.ml-1 against both B. cereus ATCC (14579) and B. subtilis, the least active compound was thiomorpholine which inhibited S. aureus (ATCC 25923) at 64 μg.ml-1. The three compounds demonstrated high affinity for the target protein (DNA gyrase) ranging from -4.63 to -5.64 Kcal/mol and even showed better ligand efficiencies than three known antibiotics; chlorobiocin, ciprofloxacin and tetracycline. This study identified the studied compounds as potential antibiotic leads with acceptable physicochemical properties and gave the molecular basis for the observed interactions between the compounds and the target protein which can be harnessed in structural optimization process.

Antituberculotic activity of actinobacteria isolated from the rare habitats.

PubMed

Hussain, A; Rather, M A; Shah, A M; Bhat, Z S; Shah, A; Ahmad, Z; Parvaiz Hassan, Q

2017-09-01

A distinctive screening procedure resulted in the isolation and identification of antituberculotic actinobacteria. In this course, a total of 125 actinobacteria were isolated from various soil samples from untapped areas in Northwestern Himalayas, India. The antibacterial screening showed that 26 isolates inhibited the growth of at least one of the tested bacterial pathogens including Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 12228), Bacillus subtilis (ATCC 11774), Micrococcus luteus (ATCC 10240), Escherichia coli (10536), Pseudomonas aeruginosa (ATCC 10145) and Klebsiella pneumonia (ATCC BAA-2146). The production media was optimized for the active strains by estimation of their extract value by the quantification of the ethyl acetate extract. The screening of fermentation products from the selected 26 bioactive isolates revealed that 10 strains have metabolites antagonistic against the standard H37Rv strain of Mycobacterium tuberculosis. The characterization by 16S rRNA gene sequencing and phylogenetic analysis demonstrated the diverse nature of these antituberculosis strains. The secondary metabolites of potent, rare strain, Lentzea violacea AS08 exhibited promising antituberculosis activity with minimal inhibitory concentration (MIC) of 3·9 μg ml -1 . The metabolites identified by gas chromatography-mass spectrometry (GC-MS) included, Phenol, 2,5-bis (1, 1-dimethylethyl), n-Hexadecanoic acid, Hexadecanoic acid methyl-ester, Hexadecanoic acid ethyl-ester and, 9,12-Octadecadienoyl chloride(Z,Z) are biologically significant molecules. The study presents the isolation of rare actinobacteria from untapped sites in the Northwestern Himalayas and their in vitro potential against Mycobacterium tuberculosis for their metabolites. The study revealed that exploring the untapped natural sources as one of the resourceful approaches for the discovery of new natural products. This study also provided strong evidence for the ability of rare and potent actinobacterial strains to produce bioactive compounds with antagonistic activity and these metabolites can be studied for inhibitory potential. © 2017 The Society for Applied Microbiology.

Differential tolerance of Sulfolobus strains to transition metals

USGS Publications Warehouse

Miller, K.W.; Sass, Risanico S.; Risatti, J.B.

1992-01-01

Sulfolobus acidocaldarius strains 98-3 and B12, and S. solfataricus ATCC 35091 were evaluated for tolerance to Cd, Co, Cu, Ni, Zn and Mg. The tolerance of strains 98-3 and ATCC 35091 to these metals was Mg > Zn > Cd > Cu ??? Co > Ni. For B12, however, the order of tolerance was Mg > Cd > Zn = Co > Ni > Cu. Tolerance to these metals is also presented as a potentially useful taxonomic indicator.

Finished Genome Sequence of the Laboratory Strain Escherichia coli K-12 RV308 (ATCC 31608).

PubMed

Krempl, Peter M; Mairhofer, Juergen; Striedner, Gerald; Thallinger, Gerhard G

2014-11-20

Escherichia coli strain K-12 substrain RV308 is an engineered descendant of the K-12 wild-type strain. Like its ancestor, it is an important organism in biotechnological research and is heavily used for the expression of single-chain variable fragments. Here, we report the complete genome sequence of E. coli K-12 RV308 (ATCC 31608). Copyright © 2014 Krempl et al.

Dose-dependent effect of lysozyme upon Candida albicans biofilm

PubMed Central

Sebaa, Sarra; Hizette, Nicolas; Boucherit-Otmani, Zahia; Courtois, Philippe

2017-01-01

The present study investigated the in vitro effect of lysozyme (0–1,000 µg/ml) on Candida albicans (C. albicans) biofilm development. Investigations were conducted on C. albicans ATCC 10231 and on 10 clinical isolates from dentures. Strains were cultured aerobically at 37°C in Sabouraud broth. Yeast growth was evaluated by turbidimetry. Biofilm biomass was quantified on a polystyrene support by crystal violet staining and on acrylic surfaces by counts of colony forming units. Lysozyme affected biofilm formation to a greater extent than it affected growth. For the ATCC 10231 reference strain, lysozyme acted as a biofilm promotor on polystyrene at the highest concentration tested (1,000 µg/ml, non-physiological). When the reference strain was investigated on acrylic resin support, lysozyme acted as a significant biofilm promotor on rough resin, but less on smooth resin. The attached biomass in the presence of physiological concentrations of lysozyme (10–30 µg/ml) was significantly decreased compared with the hypothetical value of 100% using a one-sample t-test, but a comparison between the different lysozyme conditions using analysis of variance and post hoc tests did not reveal significant differences. In 10 wild strains, different patterns of biofilm formation on polystyrene were observed in the presence of lysozyme. Some strains, characterized by large amounts of biofilm formation in the presence of 1,000 µg/ml lysozyme, were poor biofilm producers at low concentrations of lysozyme. In contrast, some strains that were poor biofilm producers with a high lysozyme concentration were more inhibited by low concentrations of lysozyme. The present study emphasizes the need to develop strategies for biofilm control based on in vitro experiments, and to implement these in clinical trials prior to approval of hygiene products enriched with exocrine proteins, such as lysozyme. Further studies will extend these investigations to other Candida species, and to fungi and bacteria present in oral biofilms. PMID:28138698

Synergistic Killing of Multidrug-Resistant Pseudomonas aeruginosa at Multiple Inocula by Colistin Combined with Doripenem in an In Vitro Pharmacokinetic/Pharmacodynamic Model ▿

PubMed Central

Bergen, Phillip J.; Tsuji, Brian T.; Bulitta, Jurgen B.; Forrest, Alan; Jacob, Jovan; Sidjabat, Hanna E.; Paterson, David L.; Nation, Roger L.; Li, Jian

2011-01-01

Combination therapy may be required for multidrug-resistant (MDR) Pseudomonas aeruginosa. The aim of this study was to systematically investigate bacterial killing and emergence of colistin resistance with colistin and doripenem combinations against MDR P. aeruginosa. Studies were conducted in a one-compartment in vitro pharmacokinetic/pharmacodynamic model for 96 h at two inocula (∼106 and ∼108 CFU/ml) against a colistin-heteroresistant reference strain (ATCC 27853) and a colistin-resistant MDR clinical isolate (19147 n/m). Four combinations utilizing clinically achievable concentrations were investigated. Microbiological response was examined by log changes and population analysis profiles. Colistin (constant concentrations of 0.5 or 2 mg/liter) plus doripenem (peaks of 2.5 or 25 mg/liter every 8 h; half-life, 1.5 h) substantially increased bacterial killing against both strains at the low inoculum, while combinations containing colistin at 2 mg/liter increased activity against ATCC 27853 at the high inoculum; only colistin at 0.5 mg/liter plus doripenem at 2.5 mg/liter failed to improve activity against 19147 n/m at the high inoculum. Combinations were additive or synergistic against ATCC 27853 in 16 and 11 of 20 cases (4 combinations across 5 sample points) at the 106- and 108-CFU/ml inocula, respectively; the corresponding values for 19147 n/m were 16 and 9. Combinations containing doripenem at 25 mg/liter resulted in eradication of 19147 n/m at the low inoculum and substantial reductions in regrowth (including to below the limit of detection at ∼50 h) at the high inoculum. Emergence of colistin-resistant subpopulations of ATCC 27853 was substantially reduced and delayed with combination therapy. This investigation provides important information for optimization of colistin-doripenem combinations. PMID:21911563

Genome sequences of three tunicamycin-producing Streptomyces strains; S. chartreusis NRRL 12338, S. chartreusis NRRL 3882, and S. lysosuperificus ATCC 31396

USDA-ARS?s Scientific Manuscript database

S. chartreusis strains NRRL 12338 and NRRL 3882, S. clavuligerus NRRL 3585, and S. lysosuperificus ATCC 31396, are known producers of tunicamycins, and also of charteusins, clavulinate, cephalosporins, holomycins, and calcimycin. Here we announce the sequencing of the S. lysosuperificus and the two...

Stimulation of epithelial cell matrix metalloproteinase (MMP-2, -9, -13) and interleukin-8 secretion by fusobacteria.

PubMed

Gursoy, U K; Könönen, E; Uitto, V-J

2008-10-01

Bacterial pathogens involved in periodontal diseases exert their destructive effects primarily by stimulating the host cells to increase their secretion of proinflammatory cytokines and matrix metalloproteinases (MMPs). This study aimed to determine the epithelial cell matrix metalloproteinase and interleukin-8 (IL-8) secretion upon exposure to fusobacteria. Eight different oral and non-oral Fusobacterium strains were incubated with HaCaT epithelial cells. Gelatin zymography and Western blot analysis were performed to detect collagenase 3 (MMP-13), gelatinase A (MMP-2), gelatinase B (MMP-9), and IL-8 secretion by epithelial cells. All Fusobacterium strains, especially Fusobacterium necrophorum ATCC 25286, Fusobacterium nucleatum ATCC 25586, and Fusobacterium varium ATCC 51644, increased MMP-9 and MMP-13 secretion. Fusobacterium simiae ATCC 33568, and to a lesser extent F. nucleatum and F. necrophorum, increased epithelial MMP-2 secretion. F. nucleatum and F. necrophorum also increased IL-8 secretion. F. varium ATCC 27725, a strain that only weakly stimulated MMP production, strongly increased the IL-8 production, suggesting that their expression is differently regulated. We conclude that the pathogenic potential of fusobacteria may partly result from their ability to stimulate secretion of MMP-9, MMP-13, and IL-8 from epithelial cells.

Multigene disruption in undomesticated Bacillus subtilis ATCC 6051a using the CRISPR/Cas9 system

PubMed Central

Zhang, Kang; Duan, Xuguo; Wu, Jing

2016-01-01

Bacillus subtilis ATCC 6051a is an undomesticated strain used in the industrial production of enzymes. Because it is poorly transformable, genetic manipulation in this strain requires a highly efficient genome editing method. In this study, a Streptococcus pyogenes CRISPR/Cas9 system consisting of an all-in-one knockout plasmid containing a target-specific guide RNA, cas9, and a homologous repair template was established for highly efficient gene disruption in B. subtilis ATCC 6051a. With an efficiency of 33% to 53%, this system was used to disrupt the srfC, spoIIAC, nprE, aprE and amyE genes of B. subtilis ATCC 6051a, which hamper its use in industrial fermentation. Compared with B. subtilis ATCC 6051a, the final mutant, BS5 (ΔsrfC, ΔspoIIAC, ΔnprE, ΔaprE, ΔamyE), produces much less foam during fermentation, displays greater resistant to spore formation, and secretes 2.5-fold more β-cyclodextrin glycosyltransferase into the fermentation medium. Thus, the CRISPR/Cas9 system proved to be a powerful tool for targeted genome editing in an industrially relevant, poorly transformable strain. PMID:27305971

Antimicrobial and anti-biofilm activities of Lactobacillus kefiranofaciens DD2 against oral pathogens

PubMed Central

2018-01-01

ABSTRACT Background: Streptococcus mutans and Streptococcus sobrinus are major causative bacterial pathogens of dental caries. Objective: We investigated the applicability of three Lactobacillus strains (L. kefiranofaciens DD2, DD5, and DD6) isolated from kefir and three commercial Lactobacillus strains (L. plantarum ATCC 10,012, L. johnsonii JCM 1022, and L. rhamnosus ATCC 7469) as potential oral probiotics with respect to their survivability in an experimental oral environment, antimicrobial activity, and anti-biofilm formation activity against S. mutans and S. sobrinus. Results: Strains DD2, ATCC 10012, ATCC 7469, and JCM 1022 had the best oral survivability, including aerotolerance and enzymatic resistance, and inhibited the growth and biofilm formation of S. mutans and S. sobrinus. In particular, DD2 suppressed all three classes of biofilm formation-associated genes: those associated with carbohydrate metabolism and those encoding regulatory biofilm and adhesion proteins. Conclusions: These results indicate that the novel kefir isolate L. kefiranofaciens DD2 effectively and directly inhibits S. mutans and S. sobrinus. PMID:29868163

Antimicrobial and anti-biofilm activities of Lactobacillus kefiranofaciens DD2 against oral pathogens.

PubMed

Jeong, Dana; Kim, Dong-Hyeon; Song, Kwang-Young; Seo, Kun-Ho

2018-01-01

Background : Streptococcus mutans and Streptococcus sobrinus are major causative bacterial pathogens of dental caries. Objective : We investigated the applicability of three Lactobacillus strains ( L. kefiranofaciens DD2, DD5, and DD6) isolated from kefir and three commercial Lactobacillus strains ( L. plantarum ATCC 10,012, L. johnsonii JCM 1022, and L. rhamnosus ATCC 7469) as potential oral probiotics with respect to their survivability in an experimental oral environment, antimicrobial activity, and anti-biofilm formation activity against S. mutans and S. sobrinus . Results : Strains DD2, ATCC 10012, ATCC 7469, and JCM 1022 had the best oral survivability, including aerotolerance and enzymatic resistance, and inhibited the growth and biofilm formation of S. mutans and S. sobrinus . In particular, DD2 suppressed all three classes of biofilm formation-associated genes: those associated with carbohydrate metabolism and those encoding regulatory biofilm and adhesion proteins. Conclusions : These results indicate that the novel kefir isolate L. kefiranofaciens DD2 effectively and directly inhibits S. mutans and S. sobrinus .

Lactobacillus fermentum ATCC 23271 Displays In vitro Inhibitory Activities against Candida spp.

PubMed Central

do Carmo, Monique S.; Noronha, Francisca M. F.; Arruda, Mariana O.; Costa, Ênnio P. da Silva; Bomfim, Maria R. Q.; Monteiro, Andrea S.; Ferro, Thiago A. F.; Fernandes, Elizabeth S.; Girón, Jorge A.; Monteiro-Neto, Valério

2016-01-01

Lactobacilli are involved in the microbial homeostasis in the female genital tract. Due to the high prevalence of many bacterial diseases of the female genital tract and the resistance of microorganisms to various antimicrobial agents, alternative means to control these infections are necessary. Thus, this study aimed to evaluate the probiotic properties of well-characterized Lactobacillus species, including L. acidophilus (ATCC 4356), L. brevis (ATCC 367), L. delbrueckii ssp. delbrueckii (ATCC 9645), L. fermentum (ATCC 23271), L. paracasei (ATCC 335), L. plantarum (ATCC 8014), and L. rhamnosus (ATCC 9595), against Candida albicans (ATCC 18804), Neisseria gonorrhoeae (ATCC 9826), and Streptococcus agalactiae (ATCC 13813). The probiotic potential was investigated by using the following criteria: (i) adhesion to host epithelial cells and mucus, (ii) biofilm formation, (iii) co-aggregation with bacterial pathogens, (iv) inhibition of pathogen adhesion to mucus and HeLa cells, and (v) antimicrobial activity. Tested lactobacilli adhered to mucin, co-aggregated with all genital microorganisms, and displayed antimicrobial activity. With the exception of L. acidophilus and L. paracasei, they adhered to HeLa cells. However, only L. fermentum produced a moderate biofilm and a higher level of co-aggregation and mucin binding. The displacement assay demonstrated that all Lactobacillus strains inhibit C. albicans binding to mucin (p < 0.001), likely due to the production of substances with antimicrobial activity. Clinical isolates belonging to the most common Candida species associated to vaginal candidiasis were inhibited by L. fermentum. Collectively, our data suggest that L. fermentum ATCC 23271 is a potential probiotic candidate, particularly to complement candidiasis treatment, since presented with the best probiotic profile in comparison with the other tested lactobacilli strains. PMID:27833605

Recombination and Insertion Events Involving the Botulinum Neurotoxin Complex Genes in Clostridium botulinum Types A, B, E and F and Clostridium butyricum Type E Strains

DTIC Science & Technology

2009-10-05

to be located within a small plasmid [11]. The genomic sequence data for the Eklund 17B strain verified the presence of bont/np b within a unique...average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed...three BoNT/A1 strains (ATCC 3502, ATCC 19397, Hall) revealed that these strains are nearly identical in genomic organization ( data not shown). The

Comparison of the virulence of exopolysaccharide-producing Prevotella intermedia to exopolysaccharide non-producing periodontopathic organisms

PubMed Central

2011-01-01

Background Evidence in the literature suggests that exopolysaccharides (EPS) produced by bacterial cells are essential for the expression of virulence in these organisms. Secreted EPSs form the framework in which microbial biofilms are built. Methods This study evaluates the role of EPS in Prevotella intermedia for the expression of virulence. This evaluation was accomplished by comparing EPS-producing P. intermedia strains 17 and OD1-16 with non-producing P. intermedia ATCC 25611 and Porphyromonas gingivalis strains ATCC 33277, 381 and W83 for their ability to induce abscess formation in mice and evade phagocytosis. Results EPS-producing P. intermedia strains 17 and OD1-16 induced highly noticeable abscess lesions in mice at 107 colony-forming units (CFU). In comparison, P. intermedia ATCC 25611 and P. gingivalis ATCC 33277, 381 and W83, which all lacked the ability to produce viscous materials, required 100-fold more bacteria (109 CFU) in order to induce detectable abscess lesions in mice. Regarding antiphagocytic activity, P. intermedia strains 17 and OD1-16 were rarely internalized by human polymorphonuclear leukocytes, but other strains were readily engulfed and detected in the phagosomes of these phagocytes. Conclusions These results demonstrate that the production of EPS by P. intermedia strains 17 and OD1-16 could contribute to the pathogenicity of this organism by conferring their ability to evade the host's innate defence response. PMID:21864411

Comparison of the virulence of exopolysaccharide-producing Prevotella intermedia to exopolysaccharide non-producing periodontopathic organisms.

PubMed

Yamanaka, Takeshi; Yamane, Kazuyoshi; Furukawa, Tomoyo; Matsumoto-Mashimo, Chiho; Sugimori, Chieko; Nambu, Takayuki; Obata, Noboru; Walker, Clay B; Leung, Kai-Poon; Fukushima, Hisanori

2011-08-25

Evidence in the literature suggests that exopolysaccharides (EPS) produced by bacterial cells are essential for the expression of virulence in these organisms. Secreted EPSs form the framework in which microbial biofilms are built. This study evaluates the role of EPS in Prevotella intermedia for the expression of virulence. This evaluation was accomplished by comparing EPS-producing P. intermedia strains 17 and OD1-16 with non-producing P. intermedia ATCC 25611 and Porphyromonas gingivalis strains ATCC 33277, 381 and W83 for their ability to induce abscess formation in mice and evade phagocytosis. EPS-producing P. intermedia strains 17 and OD1-16 induced highly noticeable abscess lesions in mice at 107 colony-forming units (CFU). In comparison, P. intermedia ATCC 25611 and P. gingivalis ATCC 33277, 381 and W83, which all lacked the ability to produce viscous materials, required 100-fold more bacteria (109 CFU) in order to induce detectable abscess lesions in mice. Regarding antiphagocytic activity, P. intermedia strains 17 and OD1-16 were rarely internalized by human polymorphonuclear leukocytes, but other strains were readily engulfed and detected in the phagosomes of these phagocytes. These results demonstrate that the production of EPS by P. intermedia strains 17 and OD1-16 could contribute to the pathogenicity of this organism by conferring their ability to evade the host's innate defence response.

Biosynthesis of human diazepam and clonazepam metabolites.

PubMed

de Paula, Núbia C; Araujo Cordeiro, Kelly C F; de Melo Souza, Paula L; Nogueira, Diogo F; da Silva e Sousa, Diego B; Costa, Maísa B; Noël, François; de Oliveira, Valéria

2015-03-01

A screening of fungal and microbial strains allowed to select the best microorganisms to produce in high yields some of the human metabolites of two benzodiazepine drugs, diazepam and clonazepam, in order to study new pharmacological activities and for chemical standard proposes. Among the microorganisms tested, Cunninghamella echinulata ATCC 9244 and Rhizopus arrhizus ATCC 11145 strains, were the most active producers of the mains metabolites of diazepam which included demethylated, hydroxylated derivatives. Beauveria bassiana ATCC 7159 and Chaetomium indicum LCP 984200 produced the 7 amino-clonazepam metabolite and a product of acid hydrolysis of this benzodiazepine. Copyright © 2015 Elsevier Ltd. All rights reserved.

Genetic homogeneity of Clostridium botulinum type A1 strains with unique toxin gene clusters.

PubMed

Raphael, Brian H; Luquez, Carolina; McCroskey, Loretta M; Joseph, Lavin A; Jacobson, Mark J; Johnson, Eric A; Maslanka, Susan E; Andreadis, Joanne D

2008-07-01

A group of five clonally related Clostridium botulinum type A strains isolated from different sources over a period of nearly 40 years harbored several conserved genetic properties. These strains contained a variant bont/A1 with five nucleotide polymorphisms compared to the gene in C. botulinum strain ATCC 3502. The strains also had a common toxin gene cluster composition (ha-/orfX+) similar to that associated with bont/A in type A strains containing an unexpressed bont/B [termed A(B) strains]. However, bont/B was not identified in the strains examined. Comparative genomic hybridization demonstrated identical genomic content among the strains relative to C. botulinum strain ATCC 3502. In addition, microarray data demonstrated the absence of several genes flanking the toxin gene cluster among the ha-/orfX+ A1 strains, suggesting the presence of genomic rearrangements with respect to this region compared to the C. botulinum ATCC 3502 strain. All five strains were shown to have identical flaA variable region nucleotide sequences. The pulsed-field gel electrophoresis patterns of the strains were indistinguishable when digested with SmaI, and a shift in the size of at least one band was observed in a single strain when digested with XhoI. These results demonstrate surprising genomic homogeneity among a cluster of unique C. botulinum type A strains of diverse origin.

Multiple functions of the leucine-rich repeat protein LrrA of Treponema denticola.

PubMed

Ikegami, Akihiko; Honma, Kiyonobu; Sharma, Ashu; Kuramitsu, Howard K

2004-08-01

The gene lrrA, encoding a leucine-rich repeat protein, LrrA, that contains eight consensus tandem repeats of 23 amino acid residues, has been identified in Treponema denticola ATCC 35405. A leucine-rich repeat is a generally useful protein-binding motif, and proteins containing this repeat are typically involved in protein-protein interactions. Southern blot analysis demonstrated that T. denticola ATCC 35405 expresses the lrrA gene, but the gene was not identified in T. denticola ATCC 33520. In order to analyze the functions of LrrA in T. denticola, an lrrA-inactivated mutant of strain ATCC 35405 and an lrrA gene expression transformant of strain ATCC 33520 were constructed. Characterization of the mutant and transformant demonstrated that LrrA is associated with the extracytoplasmic fraction of T. denticola and expresses multifunctional properties. It was demonstrated that the attachment of strain ATCC 35405 to HEp-2 cell cultures and coaggregation with Tannerella forsythensis were attenuated by the lrrA mutation. In addition, an in vitro binding assay demonstrated specific binding of LrrA to a portion of the Tannerella forsythensis leucine-rich repeat protein, BspA, which is mediated by the N-terminal region of LrrA. It was also observed that the lrrA mutation caused a reduction of swarming in T. denticola ATCC 35405 and consequently attenuated tissue penetration. These results suggest that the leucine-rich repeat protein LrrA plays a role in the attachment and penetration of human epithelial cells and coaggregation with Tannerella forsythensis. These properties may play important roles in the virulence of T. denticola.

Quantification of the Effects of Salt Stress and Physiological State on Thermotolerance of Bacillus cereus ATCC 10987 and ATCC 14579

PubMed Central

den Besten, Heidy M. W.; Mataragas, Marios; Moezelaar, Roy; Abee, Tjakko; Zwietering, Marcel H.

2006-01-01

The food-borne pathogen Bacillus cereus can acquire enhanced thermal resistance through multiple mechanisms. Two Bacillus cereus strains, ATCC 10987 and ATCC 14579, were used to quantify the effects of salt stress and physiological state on thermotolerance. Cultures were exposed to increasing concentrations of sodium chloride for 30 min, after which their thermotolerance was assessed at 50°C. Linear and nonlinear microbial survival models, which cover a wide range of known inactivation curvatures for vegetative cells, were fitted to the inactivation data and evaluated. Based on statistical indices and model characteristics, biphasic models with a shoulder were selected and used for quantification. Each model parameter reflected a survival characteristic, and both models were flexible, allowing a reduction of parameters when certain phenomena were not present. Both strains showed enhanced thermotolerance after preexposure to (non)lethal salt stress conditions in the exponential phase. The maximum adaptive stress response due to salt preexposure demonstrated for exponential-phase cells was comparable to the effect of physiological state on thermotolerance in both strains. However, the adaptive salt stress response was less pronounced for transition- and stationary-phase cells. The distinct tailing of strain ATCC 10987 was attributed to the presence of a subpopulation of spores. The existence of a stable heat-resistant subpopulation of vegetative cells could not be demonstrated for either of the strains. Quantification of the adaptive stress response might be instrumental in understanding adaptation mechanisms and will allow the food industry to develop more accurate and reliable stress-integrated predictive modeling to optimize minimal processing conditions. PMID:16957208

Role of Acinetobactin-Mediated Iron Acquisition Functions in the Interaction of Acinetobacter baumannii Strain ATCC 19606T with Human Lung Epithelial Cells, Galleria mellonella Caterpillars, and Mice

PubMed Central

Gaddy, Jennifer A.; Arivett, Brock A.; McConnell, Michael J.; López-Rojas, Rafael; Pachón, Jerónimo

2012-01-01

Acinetobacter baumannii, which causes serious infections in immunocompromised patients, expresses high-affinity iron acquisition functions needed for growth under iron-limiting laboratory conditions. In this study, we determined that the initial interaction of the ATCC 19606T type strain with A549 human alveolar epithelial cells is independent of the production of BasD and BauA, proteins needed for acinetobactin biosynthesis and transport, respectively. In contrast, these proteins are required for this strain to persist within epithelial cells and cause their apoptotic death. Infection assays using Galleria mellonella larvae showed that impairment of acinetobactin biosynthesis and transport functions significantly reduces the ability of ATCC 19606T cells to persist and kill this host, a defect that was corrected by adding inorganic iron to the inocula. The results obtained with these ex vivo and in vivo approaches were validated using a mouse sepsis model, which showed that expression of the acinetobactin-mediated iron acquisition system is critical for ATCC 19606T to establish an infection and kill this vertebrate host. These observations demonstrate that the virulence of the ATCC 19606T strain depends on the expression of a fully active acinetobactin-mediated system. Interestingly, the three models also showed that impairment of BasD production results in an intermediate virulence phenotype compared to those of the parental strain and the BauA mutant. This observation suggests that acinetobactin intermediates or precursors play a virulence role, although their contribution to iron acquisition is less relevant than that of mature acinetobactin. PMID:22232188

Kocuria polaris sp. nov., an orange-pigmented psychrophilic bacterium isolated from an Antarctic cyanobacterial mat sample.

PubMed

Reddy, Gundlapally S N; Prakash, Jogadhenu S S; Prabahar, Vadivel; Matsumoto, Genki I; Stackebrandt, Erko; Shivaji, Sisinthy

2003-01-01

Strain CMS 76orT, an orange-pigmented bacterium, was isolated from a cyanobacterial mat sample from a pond located in McMurdo Dry Valley, Antarctica. On the basis of chemotaxonomic and phylogenetic properties, strain CMS 76orT was identified as a member of the genus Kocuria. It exhibited a 16S rDNA similarity of 99.8% and DNA-DNA similarity of 71% with Kocuria rosea (ATCC 186T). Phenotypic traits confirmed that strain CMS 78orT and K. rosea were well differentiated. Furthermore, strain CMS 76orT could be differentiated from the other reported species of Kocuria, namely Kocuria kristinae (ATCC 27570T), Kocuria varians (ATCC 15306T), Kocuria rhizophila (DSM 11926T) and Kocuria palustris (DSM 11025T), on the basis of a number of phenotypic features. Therefore, it is proposed that strain CMS 76orT (= MTCC 3702T = DSM 14382T) be assigned to a novel species of the genus Kocuria, as Kocuria polaris.

Use of PCR and Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis Techniques for Differentiation of Prevotella intermedia Sensu Stricto and Prevotella nigrescens

PubMed Central

Premaraj, Thyagaseely; Kato, Naoki; Fukui, Katsuhito; Kato, Haru; Watanabe, Kunitomo

1999-01-01

Primers were designed from 16S rRNA sequences of Prevotella intermedia sensu stricto and Prevotella nigrescens and were used to discriminate these two species by PCR. The results were compared with those from the PCR technique using primers designed from arbitrarily primed PCR products by Guillot and Mouton (E. Guillot and C. Mouton, J. Clin. Microbiol. 35:1876–1882, 1997). The specificities of both assays were studied by using P. intermedia ATCC 25611, P. nigrescens ATCC 33563, 174 clinical isolates of P. intermedia sensu lato, and 59 reference strains and 58 clinical isolates of other Prevotella species and/or common oral flora. In addition, the usefulness and reliability of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the differentiation of the two species were examined by comparing the results with those from PCR assays. The controversial lipase test for distinguishing these species was also carried out. Unambiguous differentiation was made by both PCR assays, and the results matched each other. The SDS-PAGE assay was found to misidentify a few strains tested, compared with the results of PCR assays. The lipase test was positive for both species, including the reference strains of P. intermedia and P. nigrescens. We conclude that both PCR assays are simple, rapid, reliable, and specific methods which could be used in clinical studies and that the lipase test is not valuable in the differentiation. The reliable discrimination of the two species by SDS-PAGE is questionable. PMID:10074526

Electrochemical Characterization of a Novel Exoelectrogenic Bacterium Strain SCS5, Isolated from a Mediator-Less Microbial Fuel Cell and Phylogenetically Related to Aeromonas jandaei.

PubMed

Sharma, Subed Chandra Dev; Feng, Cuijie; Li, Jiangwei; Hu, Anyi; Wang, Han; Qin, Dan; Yu, Chang-Ping

2016-09-29

A facultative anaerobic bacterium, designated as strain SCS5, was isolated from the anodic biofilm of a mediator-less microbial fuel cell using acetate as the electron donor and α-FeOOH as the electron acceptor. The isolate was Gram-negative, motile, and shaped as short rods (0.9-1.3 μm in length and 0.4-0.5 μm in width). A phylogenetic analysis of the 16S rRNA, gyrB, and rpoD genes suggested that strain SCS5 belonged to the Aeromonas genus in the Aeromonadaceae family and exhibited the highest 16S rRNA gene sequence similarity (99.45%) with Aeromonas jandaei ATCC 49568. However, phenotypic, cellular fatty acid profile, and DNA G+C content analyses revealed that there were some distinctions between strain SCS5 and the type strain A. jandaei ATCC 49568. The optimum growth temperature, pH, and NaCl (%) for strain SCS5 were 35°C, 7.0, and 0.5% respectively. The DNA G+C content of strain SCS5 was 59.18%. The isolate SCS5 was capable of reducing insoluble iron oxide (α-FeOOH) and transferring electrons to extracellular material (the carbon electrode). The electrochemical activity of strain SCS5 was corroborated by cyclic voltammetry and a Raman spectroscopic analysis. The cyclic voltammogram of strain SCS5 revealed two pairs of oxidation-reduction peaks under anaerobic and aerobic conditions. In contrast, no redox pair was observed for A. jandaei ATCC 49568. Thus, isolated strain SCS5 is a novel exoelectrogenic bacterium phylogenetically related to A. jandaei, but shows distinct electrochemical activity from its close relative A. jandaei ATCC 49568.

Complete genome sequence of Campylobacter concisus ATCC 33237T and draft genome sequences for an additional eight well-characterized C. concisus strains

USDA-ARS?s Scientific Manuscript database

This report includes the complete genome of the Campylobacter concisus type strain ATCC 33237T and the draft genomes of eight additional well characterized C. concisus genomes. C. concisus has been shown to be a genetically heterogeneous species and these nine genomes provide valuable information re...

Antibacterial activity of Lactobacillus spp. isolated from the feces of healthy infants against enteropathogenic bacteria.

PubMed

Davoodabadi, Abolfazl; Soltan Dallal, Mohammad Mehdi; Rahimi Foroushani, Abbas; Douraghi, Masoumeh; Sharifi Yazdi, Mohammad Kazem; Amin Harati, Farzaneh

2015-08-01

Lactobacilli are normal microflora of the gastrointestinal (GI) tract and are a heterogeneous group of lactic acid bacteria (LAB). Lactobacillus strains with Probiotic activity may have health Benefits for human. This study investigates the probiotic potential of Lactobacillus strains obtained from the feces of healthy infants and also explores antibacterial activity of Lactobacillus strains with probiotic potential against enteropathogenic bacteria. Fecal samples were collected from 95 healthy infants younger than 18 months. Two hundred and ninety Lactobacillus strains were isolated and assessed for probiotic potential properties including ability to survive in gastrointestinal conditions (pH 2.0, 0.3% oxgall), adherence to HT-29 cells and antibiotic resistance. Six strains including Lactobacillus fermentum (4 strains), Lactobacillus paracasei and Lactobacillus plantarum showed good probiotic potential and inhibited the growth of enteropathogenic bacteria including ETEC H10407, Shigella flexneri ATCC 12022, Shigella sonnei ATCC 9290, Salmonella enteritidis H7 and Yersinia enterocolitica ATCC 23715. These Lactobacillus strains with probiotic potential may be useful for prevention or treatment of diarrhea, but further in vitro and in vivo studies on these strains are still required. Copyright © 2015 Elsevier Ltd. All rights reserved.

Characterization of Pro-Inflammatory Flagellin Proteins Produced by Lactobacillus ruminis and Related Motile Lactobacilli

PubMed Central

Neville, B. Anne; Forde, Brian M.; Claesson, Marcus J.; Darby, Trevor; Coghlan, Avril; Nally, Kenneth; Ross, R. Paul; O’Toole, Paul W.

2012-01-01

Lactobacillus ruminis is one of at least twelve motile but poorly characterized species found in the genus Lactobacillus. Of these, only L. ruminis has been isolated from mammals, and this species may be considered as an autochthonous member of the gastrointestinal microbiota of humans, pigs and cows. Nine L. ruminis strains were investigated here to elucidate the biochemistry and genetics of Lactobacillus motility. Six strains isolated from humans were non-motile while three bovine isolates were motile. A complete set of flagellum biogenesis genes was annotated in the sequenced genomes of two strains, ATCC25644 (human isolate) and ATCC27782 (bovine isolate), but only the latter strain produced flagella. Comparison of the L. ruminis and L. mali DSM20444T motility loci showed that their genetic content and gene-order were broadly similar, although the L. mali motility locus was interrupted by an 11.8 Kb region encoding rhamnose utilization genes that is absent from the L. ruminis motility locus. Phylogenetic analysis of 39 motile bacteria indicated that Lactobacillus motility genes were most closely related to those of motile carnobacteria and enterococci. Transcriptome analysis revealed that motility genes were transcribed at a significantly higher level in motile L. ruminis ATCC27782 than in non-motile ATCC25644. Flagellin proteins were isolated from L. ruminis ATCC27782 and from three other Lactobacillus species, while recombinant flagellin of aflagellate L. ruminis ATCC25644 was expressed and purified from E. coli. These native and recombinant Lactobacillus flagellins, and also flagellate L. ruminis cells, triggered interleukin-8 production in cultured human intestinal epithelial cells in a manner suppressed by short interfering RNA directed against Toll-Like Receptor 5. This study provides genetic, transcriptomic, phylogenetic and immunological insights into the trait of flagellum-mediated motility in the lactobacilli. PMID:22808200

Protective effect of Lactobacillus casei strain Shirota against lethal infection with multi-drug resistant Salmonella enterica serovar Typhimurium DT104 in mice.

PubMed

Asahara, T; Shimizu, K; Takada, T; Kado, S; Yuki, N; Morotomi, M; Tanaka, R; Nomoto, K

2011-01-01

The anti-infectious activity of lactobacilli against multi-drug resistant Salmonella enterica serovar Typhimurium DT104 (DT104) was examined in a murine model of an opportunistic antibiotic-induced infection. Explosive intestinal growth and subsequent lethal extra-intestinal translocation after oral infection with DT104 during fosfomycin (FOM) administration was significantly inhibited by continuous oral administration of Lactobacillus casei strain Shirota (LcS), which is naturally resistant to FOM, at a dose of 10(8) colony-forming units per mouse daily to mice. Comparison of the anti-Salmonella activity of several Lactobacillus type strains with natural resistance to FOM revealed that Lactobacillus brevis ATCC 14869(T) , Lactobacillus plantarum ATCC 14917(T) , Lactobacillus reuteri JCM 1112(T) , Lactobacillus rhamnosus ATCC 7469(T) and Lactobacillus salivarius ATCC 11741(T) conferred no activity even when they obtained the high population levels almost similar to those of the effective strains such as LcS, Lact. casei ATCC 334(T) and Lactobacillus zeae ATCC 15820(T) . The increase in concentration of organic acids and maintenance of the lower pH in the intestine because of Lactobacillus colonization were correlated with the anti-infectious activity. Moreover, heat-killed LcS was not protective against the infection, suggesting that the metabolic activity of lactobacilli is important for the anti-infectious activity. These results suggest that certain lactobacilli in combination with antibiotics may be useful for prophylaxis against opportunistic intestinal infections by multi-drug resistant pathogens, such as DT104. Antibiotics such as FOM disrupt the metabolic activity of the intestinal microbiota that produce organic acids, and that only probiotic strains that are metabolically active in vivo should be selected to prevent intestinal infection when used clinically in combination with certain antibiotics. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

Characterization and antimicrobial application of biosynthesized gold and silver nanoparticles by using Microbacterium resistens.

PubMed

Wang, Chao; Singh, Priyanka; Kim, Yeon Ju; Mathiyalagan, Ramya; Myagmarjav, Davaajargal; Wang, Dandan; Jin, Chi-Gyu; Yang, Deok Chun

2016-11-01

Various microorganisms were found to be cable of synthesizing gold and silver nanoparticles when gold and silver salts were supplied in the reaction system. The main objective of this study was to evaluate the extracellular synthesis of gold and silver nanoparticles by the type strain Microbacterium resistens(T) [KACC14505]. The biosynthesized gold and silver nanoparticles were characterized by ultraviolet-visible spectroscopy (UV-Vis), field emission transmission electron micrograph (FE-TEM), energy dispersive X-ray spectroscopy (EDX), elemental mapping, and dynamic light scattering (DLS). Moreover, the nanoparticles were evaluated for antimicrobial potential against various pathogenic microorganisms such as Vibrio parahaemolyticus [ATCC 33844], Salmonella enterica [ATCC 13076], Staphylococcus aureus [ATCC 6538], Bacillus anthracis [NCTC 10340], Bacillus cereus [ATCC 14579], Escherichia coli [ATCC 10798], and Candida albicans [KACC 30062]. The silver nanoparticles were found as a potent antimicrobial agent whereas gold nanoparticles not showed any ability. Therefore, the current study describes the simple, green, and extracellular synthesis of gold and silver nanoparticles by the type strain Microbacterium resistens(T) [KACC14505].

Comparative Genomic Hybridization Analysis of Two Predominant Nordic Group I (Proteolytic) Clostridium botulinum Type B Clusters▿ †

PubMed Central

Lindström, Miia; Hinderink, Katja; Somervuo, Panu; Kiviniemi, Katri; Nevas, Mari; Chen, Ying; Auvinen, Petri; Carter, Andrew T.; Mason, David R.; Peck, Michael W.; Korkeala, Hannu

2009-01-01

Comparative genomic hybridization analysis of 32 Nordic group I Clostridium botulinum type B strains isolated from various sources revealed two homogeneous clusters, clusters BI and BII. The type B strains differed from reference strain ATCC 3502 by 413 coding sequence (CDS) probes, sharing 88% of all the ATCC 3502 genes represented on the microarray. The two Nordic type B clusters differed from each other by their response to 145 CDS probes related mainly to transport and binding, adaptive mechanisms, fatty acid biosynthesis, the cell membranes, bacteriophages, and transposon-related elements. The most prominent differences between the two clusters were related to resistance to toxic compounds frequently found in the environment, such as arsenic and cadmium, reflecting different adaptive responses in the evolution of the two clusters. Other relatively variable CDS groups were related to surface structures and the gram-positive cell wall, suggesting that the two clusters possess different antigenic properties. All the type B strains carried CDSs putatively related to capsule formation, which may play a role in adaptation to different environmental and clinical niches. Sequencing showed that representative strains of the two type B clusters both carried subtype B2 neurotoxin genes. As many of the type B strains studied have been isolated from foods or associated with botulism, it is expected that the two group I C. botulinum type B clusters present a public health hazard in Nordic countries. Knowing the genetic and physiological markers of these clusters will assist in targeting control measures against these pathogens. PMID:19270141

Effects of phosphoenolpyruvate carboxylase desensitization on glutamic acid production in Corynebacterium glutamicum ATCC 13032.

PubMed

Wada, Masaru; Sawada, Kazunori; Ogura, Kotaro; Shimono, Yuta; Hagiwara, Takuya; Sugimoto, Masakazu; Onuki, Akiko; Yokota, Atsushi

2016-02-01

Phosphoenolpyruvate carboxylase (PEPC) in Corynebacterium glutamicum ATCC13032, a glutamic-acid producing actinobacterium, is subject to feedback inhibition by metabolic intermediates such as aspartic acid and 2-oxoglutaric acid, which implies the importance of PEPC in replenishing oxaloacetic acid into the TCA cycle. Here, we investigated the effects of feedback-insensitive PEPC on glutamic acid production. A single amino-acid substitution in PEPC, D299N, was found to relieve the feedback control by aspartic acid, but not by 2-oxoglutaric acid. A simple mutant, strain R1, having the D299N substitution in PEPC was constructed from ATCC 13032 using the double-crossover chromosome replacement technique. Strain R1 produced glutamic acid at a concentration of 31.0 g/L from 100 g/L glucose in a jar fermentor culture under biotin-limited conditions, which was significantly higher than that of the parent, 26.0 g/L (1.19-fold), indicative of the positive effect of desensitized PEPC on glutamic acid production. Another mutant, strain DR1, having both desensitized PEPC and PYK-gene deleted mutations, was constructed in a similar manner using strain D1 with a PYK-gene deleted mutation as the parent. This mutation had been shown to enhance glutamic acid production in our previous study. Although marginal, strain D1 produced higher glutamic acid, 28.8 g/L, than ATCC13032 (1.11-fold). In contrast, glutamic acid production by strain DR-1 was elevated up to 36.9 g/L, which was 1.42-fold higher than ATCC13032 and significantly higher than the other three strains. The results showed a synergistic effect of these two mutations on glutamic acid production in C. glutamicum. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

[Analysis of virulence factors of Porphyromonas endodontalis based on comparative proteomics technique].

PubMed

Li, H; Ji, H; Wu, S S; Hou, B X

2016-12-09

Objective: To analyze the protein expression profile and the potential virulence factors of Porphyromonas endodontalis (Pe) via comparison with that of two strains of Porphyromonas gingivalis (Pg) with high and low virulences, respectively. Methods: Whole cell comparative proteomics of Pe ATCC35406 was examined and compared with that of high virulent strain Pg W83 andlow virulent strain Pg ATCC33277, respectively. Isobaric tags for relative and absolute quantitation (iTRAQ) combined with nano liquid chromatography-tandem mass spectrometry (Nano-LC-MS/MS) were adopted to identify and quantitate the proteins of Pe and two strains of Pg with various virulences by using the methods of isotopically labeled peptides, mass spectrometric detection and bioinformatics analysis. The biological functions of similar proteins expressed by Pe ATCC35406 and two strains of Pg were quantified and analyzed. Results: Totally 1 210 proteins were identified while Pe compared with Pg W83. There were 130 proteins (10.74% of the total proteins) expressed similarly, including 89 known functional proteins and 41 proteins of unknown functions. Totally 1 223 proteins were identified when Pe compared with Pg ATCC33277. There were 110 proteins (8.99% of the total proteins) expressed similarly, including 72 known functional proteins and 38 proteins of unknown functions. The similarly expressed proteins in Pe and Pg strains with various virulences mainly focused on catalytic activity and binding function, including recombination activation gene (RagA), lipoprotein, chaperonin Dnak, Clp family proteins (ClpC and ClpX) and various iron-binding proteins. They were involved in metabolism and cellular processes. In addition, the type and number of similar virulence proteins between Pe and high virulence Pg were higher than those between Pe and low virulence Pg. Conclusions: Lipoprotein, oxygen resistance protein, iron binding protein were probably the potential virulence factors of Pe ATCC35406. It was speculated that pathogenicity of Pe was more similar to high virulence Pg than that to low virulence strain.

Characterization of Aeromonas hydrophila wound pathotypes by comparative genomic and functional analyses of virulence genes.

PubMed

Grim, Christopher J; Kozlova, Elena V; Sha, Jian; Fitts, Eric C; van Lier, Christina J; Kirtley, Michelle L; Joseph, Sandeep J; Read, Timothy D; Burd, Eileen M; Tall, Ben D; Joseph, Sam W; Horneman, Amy J; Chopra, Ashok K; Shak, Joshua R

2013-04-23

Aeromonas hydrophila has increasingly been implicated as a virulent and antibiotic-resistant etiologic agent in various human diseases. In a previously published case report, we described a subject with a polymicrobial wound infection that included a persistent and aggressive strain of A. hydrophila (E1), as well as a more antibiotic-resistant strain of A. hydrophila (E2). To better understand the differences between pathogenic and environmental strains of A. hydrophila, we conducted comparative genomic and functional analyses of virulence-associated genes of these two wound isolates (E1 and E2), the environmental type strain A. hydrophila ATCC 7966(T), and four other isolates belonging to A. aquariorum, A. veronii, A. salmonicida, and A. caviae. Full-genome sequencing of strains E1 and E2 revealed extensive differences between the two and strain ATCC 7966(T). The more persistent wound infection strain, E1, harbored coding sequences for a cytotoxic enterotoxin (Act), a type 3 secretion system (T3SS), flagella, hemolysins, and a homolog of exotoxin A found in Pseudomonas aeruginosa. Corresponding phenotypic analyses with A. hydrophila ATCC 7966(T) and SSU as reference strains demonstrated the functionality of these virulence genes, with strain E1 displaying enhanced swimming and swarming motility, lateral flagella on electron microscopy, the presence of T3SS effector AexU, and enhanced lethality in a mouse model of Aeromonas infection. By combining sequence-based analysis and functional assays, we characterized an A. hydrophila pathotype, exemplified by strain E1, that exhibited increased virulence in a mouse model of infection, likely because of encapsulation, enhanced motility, toxin secretion, and cellular toxicity. Aeromonas hydrophila is a common aquatic bacterium that has increasingly been implicated in serious human infections. While many determinants of virulence have been identified in Aeromonas, rapid identification of pathogenic versus nonpathogenic strains remains a challenge for this genus, as it is for other opportunistic pathogens. This paper demonstrates, by using whole-genome sequencing of clinical Aeromonas strains, followed by corresponding virulence assays, that comparative genomics can be used to identify a virulent subtype of A. hydrophila that is aggressive during human infection and more lethal in a mouse model of infection. This aggressive pathotype contained genes for toxin production, toxin secretion, and bacterial motility that likely enabled its pathogenicity. Our results highlight the potential of whole-genome sequencing to transform microbial diagnostics; with further advances in rapid sequencing and annotation, genomic analysis will be able to provide timely information on the identities and virulence potential of clinically isolated microorganisms.

Antimicrobial activity of jasmine oil against oral microorganisms

NASA Astrophysics Data System (ADS)

Thaweboon, S.; Thaweboon, B.; Kaypetch, R.

2018-02-01

Jasmine sambac is a species of jasmine indigenous to the tropical and warm temperature regions in particular West and Southeast Asia. Essential oil extracted from the flowers of J. sambac has been shown to have anti-oxidant activity. However, very little information regarding antimicrobial activity especially oral microorganisms exists. Objective: To investigate antimicrobial effect of essential oil extracted from flowers of J. sambac against various oral microorganisms. Materials and Methods: Oral microbial strains used in the study were Streptococcus mutans KPSK2, Staphylococcus aureus ATCC 5638, Lactobacillus casei ATCC 6363, Klebsiella pneumoniae (clinical isolate), Escherichia coli ATCC 25922, Candida albicans ATCC 10231, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida tropicalis (clinical isolate), Candida glabrata ATCC 90030, Candida pseudotropicalis (clinical isolate) and Candida stellatoidia (clinical isolate). The potential of microbial growth inhibition of the oil was firstly screened by Kirby-Bauer disk diffusion method and then the minimum inhibitory concentration (MIC) was determined by agar dilution method. Results: Jasmine oil showed antimicrobial activities against S. mutans, L. casei, E. coli and all strains of Candida species with the zones of inhibition ranging from 9 to 26 mm and MIC values of 0.19-1.56 %v/v. Conclusion: Results from the present study are scientific evidence to demonstrate that jasmine oil could be employed as a natural antimicrobial agent against oral microorganisms.

Biochemical, molecular, and virulence characteristics of select Mycobacterium marinum isolates in hybrid striped bass Morone chrysops x M. saxatilis and zebrafish Danio rerio.

PubMed

Ostland, V E; Watral, V; Whipps, C M; Austin, F W; St-Hilaire, S; Westerman, M E; Kent, M L

2008-04-01

A panel of 15 Mycobacterium marinum isolates was characterized by biochemical tests, sequencing the ribosomal DNA intergenic spacer (ITS) region and the heat shock protein 65 gene (hsp65) and pulsed-field gel electrophoresis (PFGE). The biochemical characteristics of all isolates were similar, except for Tween 80 hydrolysis. DNA sequence of hsp65 for a subset of isolates were identical; however, at position 5 of the ITS rDNA, a single nucleotide polymorphism was identified. Isolates possessing a guanine residue at this position (G strains) were unable to hydrolyze Tween 80, while isolates that contained an adenine residue at this position (A strains) were positive for Tween 80 hydrolysis. PFGE successfully discriminated between the G and A strains; all G strains had identical AseI restriction enzyme-cutting patterns while the A strains exhibited a variety of cutting patterns. Eight isolates (4 G and 4 A strains) were further characterized for virulence by experimental infection of hybrid striped bass (HSB) Morone chrysops x M. saxatilis and zebrafish Danio rerio. Seven of the 8 strains produced cumulative mortality ranging from 13.3 to 83.3% in the HSB virulence trial. The M. marinum reference strain ATCC 927T did not produce mortality in HSB. HSB exposed to the G strains had significantly higher cumulative mortality than those exposed to the A strains. When these same isolates were tested in zebrafish, 6 of the 8 strains caused 100% cumulative mortality, with 2 of the A strains being the most pathogenic. In zebrafish, however, ATCC 927T was virulent and produced 28.5% mortality. Collectively, we conclude that the M. marinum G strains are unique and may represent a distinct virulence phenotype in HSB, but this trend was not consistent in zebrafish.

Listeria monocytogenes ATCC 35152 and NCTC 7973 contain a nonhemolytic, nonvirulent variant.

PubMed Central

Pine, L; Weaver, R E; Carlone, G M; Pienta, P A; Rocourt, J; Goebel, W; Kathariou, S; Bibb, W F; Malcolm, G B

1987-01-01

Listeria monocytogenes NCTC 7973 and this same strain deposited as ATCC 35152 contain two phenotypes: hemolytic virulent colonies and nonvirulent colonies that show no zones of hemolysis when streaked on heart infusion agar containing 5% rabbit blood. Results of examinations of these virulent and nonvirulent strains by investigators at the Centers for Disease Control, Atlanta, Ga., the Pasteur Institute, Paris, France, and the University of Würzburg, Federal Republic of Germany, support the conclusion that the avirulent strain is a nonhemolytic mutant of the virulent strain and that hemolysin is a virulence factor for L. monocytogenes. Images PMID:3121669

Microbial cleavage of organic C-S bonds

DOEpatents

Kilbane, J.J. II.

1994-10-25

A microbial process is described for selective cleavage of organic C-S bonds which may be used for reducing the sulfur content of sulfur-containing organic carbonaceous materials. Microorganisms of Rhodococcus rhodochrous and Bacillus sphaericus have been found which have the ability of selective cleavage of organic C-S bonds. Particularly preferred microorganisms are Rhodococcus rhodochrous strain ATCC 53968 and Bacillus sphaericus strain ATCC 53969 and their derivatives.

Microbial cleavage of organic C-S bonds

DOEpatents

Kilbane, II, John J.

1994-01-01

A microbial process for selective cleavage of organic C--S bonds which may be used for reducing the sulfur content of sulfur-containing organic carbonaceous materials, Microorganisms of Rhodococcus rhodochrous and Bacillus sphaericus have been found which have the ability of selective cleavage of organic C--S bonds. Particularly preferred microorganisms are Rhodococcus rhodochrous strain ATCC 53968 and Bacillus sphaericus strain ATCC 53969 and their derivatives.

A New Dihydrochromone Dimer and Other Secondary Metabolites from Cultures of the Marine Sponge-Associated Fungi Neosartorya fennelliae KUFA 0811 and Neosartorya tsunodae KUFC 9213

PubMed Central

Dethoup, Tida; Gales, Luís; Inácio, Ângela; Lee, Michael; Sekeroglu, Nazim

2017-01-01

A previously unreported dihydrochromone dimer, paecilin E (1), was isolated, together with eleven known compounds: β-sitostenone, ergosta-4,6,8 (14), 22-tetraen-3-one, cyathisterone, byssochlamic acid, dehydromevalonic acid lactone, chevalone B, aszonalenin, dankasterone A (2), helvolic acid, secalonic acid A and fellutanine A, from the culture filtrate extract of the marine sponge-associated fungus Neosartorya fennelliae KUFA 0811. Nine previously reported metabolites, including a chromanol derivative (3), (3β, 5α, 22E), 3,5-dihydroxyergosta-7,22-dien-6-one (4), byssochlamic acid, hopan-3β,22-diol, chevalone C, sartorypyrone B, helvolic acid, lumichrome and the alkaloid harmane were isolated from the culture of the marine-sponge associated fungus Neosartorya tsunodae KUFC 9213. Paecilin E (1), dankasterone A (2), a chromanol derivative (3), (3β, 5α, 22E)-3,5-dihydroxyergosta-7,22-dien-6-one (4), hopan-3β,22-diol (5), lumichrome (6), and harmane (7) were tested for their antibacterial activity against Gram-positive and Gram-negative reference and multidrug-resistant strains isolated from the environment. While paecilin E (1) was active against S. aureus ATCC 29213 and E. faecalis ATCC 29212, dankastetrone A (2) was only effective against E. faecalis ATCC 29212 and the multidrug-resistant VRE E. faecalis A5/102. Both compounds neither inhibit biofilm mass production in any of the strains at the concentrations tested nor exhibit synergistic association with antibiotics. PMID:29194412

In vitro assessment of Pediococcus acidilactici Kp10 for its potential use in the food industry.

PubMed

Abbasiliasi, Sahar; Tan, Joo Shun; Bashokouh, Fatemeh; Ibrahim, Tengku Azmi Tengku; Mustafa, Shuhaimi; Vakhshiteh, Faezeh; Sivasamboo, Subhashini; Ariff, Arbakariya B

2017-05-23

Selection of a microbial strain for the incorporation into food products requires in vitro and in vivo evaluations. A bacteriocin-producing lactic acid bacterium (LAB), Pediococcus acidilactici Kp10, isolated from a traditional dried curd was assessed in vitro for its beneficial properties as a potential probiotic and starter culture. The inhibitory spectra of the bacterial strain against different gram-positive and gram-negative bacteria, its cell surface hydrophobicity and resistance to phenol, its haemolytic, amylolytic and proteolytic activities, ability to produce acid and coagulate milk together with its enzymatic characteristics and adhesion property were all evaluated in vitro. P. acidilactici Kp10 was moderately tolerant to phenol and adhere to mammalian epithelial cells (Vero cells and ileal mucosal epithelium). The bacterium also exhibited antimicrobial activity against several gram-positive and gram-negative food-spoilage and food-borne pathogens such as Listeria monocytgenes ATCC 15313, Salmonella enterica ATCC 13311, Shigella sonnei ATCC 9290, Klebsiella oxytoca ATCC 13182, Enterobacter cloaca ATCC 35030 and Streptococcus pyogenes ATCC 12378. The absence of haemolytic activity and proteinase (trypsin) and the presence of a strong peptidase (leucine-arylamidase) and esterase-lipase (C4 and C8) were observed in this LAB strain. P. acidilactici Kp10 also produced acid, coagulated milk and has demonstrated proteolytic and amylolactic activities. The properties exhibited by P. acidilactici Kp10 suggested its potential application as probiotic and starter culture in the food industry.

Composition and antimicrobial activity of Marrubium incanum Desr. (Lamiaceae) essential oil.

PubMed

Petrović, Silvana; Pavlović, Milica; Maksimović, Zoran; Milenković, Marina; Couladis, Maria; Tzakouc, Olga; Niketić, Marjan

2009-03-01

The essential oil from the aerial parts of Marrubium incanum Desr. (Lamiaceae), obtained by hydrodistillation, was analyzed by GC and GC-MS. Forty-six compounds were identified, representing 96.3% of the total oil. The main components of the oil were (E)-caryophyllene (27.0%), germacrene D (26.2%) and bicyclogermacrene (11.5%). The microbial growth inhibitory properties of the isolated essential oil were determined using the agar diffusion and broth microdilution method against seven bacterial species (Staphylococcus aureus ATCC 25923, S. epidermidis ATCC 12228, Micrococcus flavus ATCC 10240, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Klebsiella pneumoniae NCIMB 9111, and Pseudomonas aeruginosa ATCC 27853), and two strains of the yeast Candida albicans (ATCC 10259 and ATCC24433). The essential oil showed activity against all the microorganisms tested, but differences in microbial susceptibility were registered.

Pathogenicity of exopolysaccharide-producing Actinomyces oris isolated from an apical abscess lesion

PubMed Central

Yamane, K; Nambu, T; Yamanaka, T; Ishihara, K; Tatami, T; Mashimo, C; Walker, C B; Leung, K-P; Fukushima, H

2013-01-01

Aim To demonstrate a capacity for producing exopolysaccharides (EPSs) and an ability to form biofilm on abiotic materials of Actinomyces oris strain K20. Methodology The productivity of EPSs and the ability to form biofilm of strain K20 were evaluated by measuring viscosity of spent culture media and by scanning electron microscopy (SEM) and the biofilm assay on microtitre plates, respectively. High-performance liquid chromatography was used to determine the chemical composition of the viscous materials. To examine the role of the viscous materials attributable to the pathogenicity in this organism, the ability of strain K20 to induce abscess formation was compared in mice to that of ATCC 27044. Results The viscosity of the spent culture media of K20 was significantly higher than that of ATCC 27044. Strain K20 showed dense meshwork structures around the cells and formed biofilms on microtitre plates, whereas ATCC 27044 did not. Chemical analysis of the viscous materials revealed that they were mainly composed of neutral sugars with mannose constituting 77.5% of the polysaccharides. Strain K20 induced persistent abscesses in mice lasting at least 5 days at a concentration of 108 cells mL−1, whereas abscesses induced by ATCC 27044 healed and disappeared or decreased in size at day 5. Conclusions Strain K20 produced EPSs, mainly consisting of mannose, and formed biofilms. This phenotype might play an important role for A. oris to express virulence through the progression of apical periodontitis. PMID:22900599

Pathogenicity of exopolysaccharide-producing Actinomyces oris isolated from an apical abscess lesion.

PubMed

Yamane, K; Nambu, T; Yamanaka, T; Ishihara, K; Tatami, T; Mashimo, C; Walker, C B; Leung, K-P; Fukushima, H

2013-02-01

To demonstrate a capacity for producing exopolysaccharides (EPSs) and an ability to form biofilm on abiotic materials of Actinomyces oris strain K20. The productivity of EPSs and the ability to form biofilm of strain K20 were evaluated by measuring viscosity of spent culture media and by scanning electron microscopy (SEM) and the biofilm assay on microtitre plates, respectively. High-performance liquid chromatography was used to determine the chemical composition of the viscous materials. To examine the role of the viscous materials attributable to the pathogenicity in this organism, the ability of strain K20 to induce abscess formation was compared in mice to that of ATCC 27044. The viscosity of the spent culture media of K20 was significantly higher than that of ATCC 27044. Strain K20 showed dense meshwork structures around the cells and formed biofilms on microtitre plates, whereas ATCC 27044 did not. Chemical analysis of the viscous materials revealed that they were mainly composed of neutral sugars with mannose constituting 77.5% of the polysaccharides. Strain K20 induced persistent abscesses in mice lasting at least 5 days at a concentration of 10(8) cells mL(-1), whereas abscesses induced by ATCC 27044 healed and disappeared or decreased in size at day 5. Strain K20 produced EPSs, mainly consisting of mannose, and formed biofilms. This phenotype might play an important role for A. oris to express virulence through the progression of apical periodontitis. © 2012 International Endodontic Journal.

Utilisation of mucin glycans by the human gut symbiont Ruminococcus gnavus is strain-dependent.

PubMed

Crost, Emmanuelle H; Tailford, Louise E; Le Gall, Gwenaelle; Fons, Michel; Henrissat, Bernard; Juge, Nathalie

2013-01-01

Commensal bacteria often have an especially rich source of glycan-degrading enzymes which allow them to utilize undigested carbohydrates from the food or the host. The species Ruminococcus gnavus is present in the digestive tract of ≥90% of humans and has been implicated in gut-related diseases such as inflammatory bowel diseases (IBD). Here we analysed the ability of two R. gnavus human strains, E1 and ATCC 29149, to utilize host glycans. We showed that although both strains could assimilate mucin monosaccharides, only R. gnavus ATCC 29149 was able to grow on mucin as a sole carbon source. Comparative genomic analysis of the two R. gnavus strains highlighted potential clusters and glycoside hydrolases (GHs) responsible for the breakdown and utilization of mucin-derived glycans. Transcriptomic and functional activity assays confirmed the importance of specific GH33 sialidase, and GH29 and GH95 fucosidases in the mucin utilisation pathway. Notably, we uncovered a novel pathway by which R. gnavus ATCC 29149 utilises sialic acid from sialylated substrates. Our results also demonstrated the ability of R. gnavus ATCC 29149 to produce propanol and propionate as the end products of metabolism when grown on mucin and fucosylated glycans. These new findings provide molecular insights into the strain-specificity of R. gnavus adaptation to the gut environment advancing our understanding of the role of gut commensals in health and disease.

Origanum vulgare subsp. hirtum essential oil prevented biofilm formation and showed antibacterial activity against planktonic and sessile bacterial cells.

PubMed

Schillaci, Domenico; Napoli, Edoardo Marco; Cusimano, Maria Grazia; Vitale, Maria; Ruberto, Andgiuseppe

2013-10-01

Essential oils from six different populations of Origanum vulgare subsp. hirtum were compared for their antibiofilm properties. The six essential oils (A to F) were characterized by a combination of gas chromatography with flame ionization detector and gas chromatography with mass spectrometer detector analyses. All oils showed weak activity against the planktonic form of a group of Staphylococcus aureus strains and against a Pseudomonas aeruginosa ATCC 15442 reference strain. The ability to inhibit biofilm formation was investigated at sub-MIC levels of 200, 100, and 50 m g/ml by staining sessile cells with safranin. Sample E showed the highest average effectiveness against all tested strains at 50 m g/ml and had inhibition percentages ranging from 30 to 52%. In the screening that used preformed biofilm from the reference strain P. aeruginosa, essential oils A through E were inactive at 200 m g/ml; F was active with a percentage of inhibition equal to 53.2%. Oregano essential oil can inhibit the formation of biofilms of various food pathogens and food spoilage organisms.

Production of astaxanthin from corn fiber as a value-added co-product of fuel ethanol fermentation

USDA-ARS?s Scientific Manuscript database

Five strains of the yeast Phaffia rhodozyma, NRRL Y-17268, NRRL Y-17270, ATCC 96594 (CBS 6938), ATCC 24202 (UCD 67-210), and ATCC 74219 (UBV-AX2) were tested for astaxanthin production using the major sugars derived from corn fiber, a byproduct from the wet milling of corn kernels that contains prim...

40 CFR 180.1102 - Trichoderma harzianum KRL-AG2 (ATCC #20847) strain T-22; exemption from requirement of a tolerance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Trichoderma harzianum KRL-AG2 (ATCC... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1102 Trichoderma harzianum KRL-AG2... of a tolerance is established for residues of the biofungicide Trichoderma harzianum KRL-AG2 (ATCC...

40 CFR 180.1102 - Trichoderma harzianum KRL-AG2 (ATCC #20847) strain T-22; exemption from requirement of a tolerance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Trichoderma harzianum KRL-AG2 (ATCC... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1102 Trichoderma harzianum KRL-AG2... of a tolerance is established for residues of the biofungicide Trichoderma harzianum KRL-AG2 (ATCC...

40 CFR 180.1102 - Trichoderma harzianum KRL-AG2 (ATCC #20847) strain T-22; exemption from requirement of a tolerance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Trichoderma harzianum KRL-AG2 (ATCC... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1102 Trichoderma harzianum KRL-AG2... of a tolerance is established for residues of the biofungicide Trichoderma harzianum KRL-AG2 (ATCC...

40 CFR 180.1102 - Trichoderma harzianum KRL-AG2 (ATCC #20847) strain T-22; exemption from requirement of a tolerance.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Trichoderma harzianum KRL-AG2 (ATCC... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1102 Trichoderma harzianum KRL-AG2... of a tolerance is established for residues of the biofungicide Trichoderma harzianum KRL-AG2 (ATCC...

40 CFR 180.1102 - Trichoderma harzianum KRL-AG2 (ATCC #20847) strain T-22; exemption from requirement of a tolerance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Trichoderma harzianum KRL-AG2 (ATCC... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1102 Trichoderma harzianum KRL-AG2... of a tolerance is established for residues of the biofungicide Trichoderma harzianum KRL-AG2 (ATCC...

Reclassification of the Specialized Metabolite Producer Pseudomonas mesoacidophila ATCC 31433 as a Member of the Burkholderia cepacia Complex.

PubMed

Loveridge, E Joel; Jones, Cerith; Bull, Matthew J; Moody, Suzy C; Kahl, Małgorzata W; Khan, Zainab; Neilson, Louis; Tomeva, Marina; Adams, Sarah E; Wood, Andrew C; Rodriguez-Martin, Daniel; Pinel, Ingrid; Parkhill, Julian; Mahenthiralingam, Eshwar; Crosby, John

2017-07-01

Pseudomonas mesoacidophila ATCC 31433 is a Gram-negative bacterium, first isolated from Japanese soil samples, that produces the monobactam isosulfazecin and the β-lactam-potentiating bulgecins. To characterize the biosynthetic potential of P. mesoacidophila ATCC 31433, its complete genome was determined using single-molecule real-time DNA sequence analysis. The 7.8-Mb genome comprised four replicons, three chromosomal (each encoding rRNA) and one plasmid. Phylogenetic analysis demonstrated that P. mesoacidophila ATCC 31433 was misclassified at the time of its deposition and is a member of the Burkholderia cepacia complex, most closely related to Burkholderia ubonensis The sequenced genome shows considerable additional biosynthetic potential; known gene clusters for malleilactone, ornibactin, isosulfazecin, alkylhydroxyquinoline, and pyrrolnitrin biosynthesis and several uncharacterized biosynthetic gene clusters for polyketides, nonribosomal peptides, and other metabolites were identified. Furthermore, P. mesoacidophila ATCC 31433 harbors many genes associated with environmental resilience and antibiotic resistance and was resistant to a range of antibiotics and metal ions. In summary, this bioactive strain should be designated B. cepacia complex strain ATCC 31433, pending further detailed taxonomic characterization. IMPORTANCE This work reports the complete genome sequence of Pseudomonas mesoacidophila ATCC 31433, a known producer of bioactive compounds. Large numbers of both known and novel biosynthetic gene clusters were identified, indicating that P. mesoacidophila ATCC 31433 is an untapped resource for discovery of novel bioactive compounds. Phylogenetic analysis demonstrated that P. mesoacidophila ATCC 31433 is in fact a member of the Burkholderia cepacia complex, most closely related to the species Burkholderia ubonensis Further investigation of the classification and biosynthetic potential of P. mesoacidophila ATCC 31433 is warranted. Copyright © 2017 Loveridge et al.

Mining Host-Pathogen Protein Interactions to Characterize Burkholderia mallei Infectivity Mechanisms

DTIC Science & Technology

2015-03-04

were shown to attenuate disease progression in an aerosol infection animal model using the virulent Burkholderia mallei ATCC 23344 strain. Here, we...performed an extended analysis of primarily nine B. mallei virulence factors and their interactions with human proteins to map out how the bacteria can...virulent Burkholderia mallei ATCC 23344 strain. Here, we performed an extended analysis of primarily nine B. mallei virulence factors and their

Selection of the Strain Lactobacillus acidophilus ATCC 43121 and Its Application to Brewers' Spent Grain Conversion into Lactic Acid

PubMed Central

Liguori, Rossana; Soccol, Carlos Ricardo; Vandenberghe, Luciana Porto de Souza; Woiciechowski, Adenise Lorenci; Ionata, Elena; Marcolongo, Loredana; Faraco, Vincenza

2015-01-01

Six Lactobacillus strains were analyzed to select a bacterium for conversion of brewers' spent grain (BSG) into lactic acid. Among the investigated strains, L. acidophilus ATCC 43121 showed the highest yield of lactic acid production (16.1 g/L after 48 hours) when grown in a synthetic medium. It was then analyzed for its ability to grow on the hydrolysates obtained from BSG after acid-alkaline (AAT) or aqueous ammonia soaking (AAS) pretreatment. The lactic acid production by L. acidophilus ATCC 43121 through fermentation of the hydrolysate from AAS treated BSG was 96% higher than that from the AAT treated one, although similar yields of lactic acid per consumed glucose were achieved due to a higher (46%) glucose consumption by L. acidophilus ATCC 43121 in the AAS BSG hydrolysate. It is worth noting that adding yeast extract to the BSG hydrolysates increased both the yield of lactic acid per substrate consumed and the volumetric productivity. The best results were obtained by fermentation of AAS BSG hydrolysate supplemented by yeast extract, in which the strain produced 22.16 g/L of lactic acid (yield of 0.61 g/g), 27% higher than the value (17.49 g/L) obtained in the absence of a nitrogen source. PMID:26640784

Emendation of genus Achromobacter and Achromobacter xylosoxidans (Yabuuchi and Yano) and proposal of Achromobacter ruhlandii (Packer and Vishniac) comb. nov., Achromobacter piechaudii (Kiredjian et al.) comb. nov., and Achromobacter xylosoxidans subsp. denitrificans (Rüger and Tan) comb. nov.

PubMed

Yabuuchi, E; Kawamura, Y; Kosako, Y; Ezaki, T

1998-01-01

Based on the results of GC content determination and 16S rRNA sequence analysis among the type strains of Achromobacter xylosoxidans, 4 Alcaligenes species, 5 Bordetella species, and 12 species of 4 other genera, the separation of genus Achromobacter Yabuuchi and Yano 1981, with the type species Achromobacter xylosoxidans, is confirmed. Alcaligenes ruhlandii (Packer and Vishniac) Aragno and Schlegel 1992 is a distinct species and not a senior synonym of Achromobacter xylosoxidans. Alcaligenes ruhlandii and Alcaligenes piechaudii Kiredjian et al 1986 are transferred to genus Achromobacter. Thus 2 new combinations, Achromobacter ruhlandii (Packer and Vishniac) and Achromobacter piechaudii (Kiredjian et al) are proposed; their type strains are ATCC 15749 and ATCC 43552, respectively. Alcaligenes denitrificans Rüger and Tan 1983 is also transferred to genus Achromobacter and ranked down to the subspecies of Achromobacter xylosoxidans. Thus a new subspecies name, Achromobacter xylosoxidans subsp. denitrificans (Rüger and Tan) is proposed. The type strain of the subspecies is ATCC 15173. This proposal automatically creates type subspecies, Achromobacter xylosoxidans subsp. xylosoxidans, with type strain ATCC 27061. An emended description of genus Achromobacter and of type species Achromobacter xylosoxidans are given.

Global response of Acidithiobacillus ferrooxidans ATCC 53993 to high concentrations of copper: A quantitative proteomics approach.

PubMed

Martínez-Bussenius, Cristóbal; Navarro, Claudio A; Orellana, Luis; Paradela, Alberto; Jerez, Carlos A

2016-08-11

Acidithiobacillus ferrooxidans is used in industrial bioleaching of minerals to extract valuable metals. A. ferrooxidans strain ATCC 53993 is much more resistant to copper than other strains of this microorganism and it has been proposed that genes present in an exclusive genomic island (GI) of this strain would contribute to its extreme copper tolerance. ICPL (isotope-coded protein labeling) quantitative proteomics was used to study in detail the response of this bacterium to copper. A high overexpression of RND efflux systems and CusF copper chaperones, both present in the genome and the GI of strain ATCC 53993 was found. Also, changes in the levels of the respiratory system proteins such as AcoP and Rus copper binding proteins and several proteins with other predicted functions suggest that numerous metabolic changes are apparently involved in controlling the effects of the toxic metal on this acidophile. Using quantitative proteomics we overview the adaptation mechanisms that biomining acidophiles use to stand their harsh environment. The overexpression of several genes present in an exclusive genomic island strongly suggests the importance of the proteins coded in this DNA region in the high tolerance of A. ferrooxidans ATCC 53993 to metals. Copyright © 2016 Elsevier B.V. All rights reserved.

Survey on the phage resistance mechanisms displayed by a dairy Lactobacillus helveticus strain.

PubMed

Zago, Miriam; Orrù, Luigi; Rossetti, Lia; Lamontanara, Antonella; Fornasari, Maria Emanuela; Bonvini, Barbara; Meucci, Aurora; Carminati, Domenico; Cattivelli, Luigi; Giraffa, Giorgio

2017-09-01

In this study the presence and functionality of phage defence mechanisms in Lactobacillus helveticus ATCC 10386, a strain of dairy origin which is sensitive to ΦLh56, were investigated. After exposure of ATCC 10386 to ΦLh56, the whole-genome sequences of ATCC 10386 and of a phage-resistant derivative (LhM3) were compared. LhM3 showed deletions in the S-layer protein and a higher expression of the genes involved in the restriction/modification (R/M) system. Genetic data were substantiated by measurements of bacteriophage adsorption rates, efficiency of plaquing, cell wall protein size and by gene expression analysis. In LhM3 two phage resistance mechanisms, the inhibition of phage adsorption and the upregulation of Type I R/M genes, take place and explain its resistance to ΦLh56. Although present in both ATCC 10386 and LhM3 genomes, the CRISPR machinery did not seem to play a role in the phage resistance of LhM3. Overall, the natural selection of phage resistant strains resulted successful in detecting variants carrying multiple phage defence mechanisms in L. helveticus. The concurrent presence of multiple phage-resistance systems should provide starter strains with increased fitness and robustness in dairy ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Volatile sulfur compounds produced by probiotic bacteria in the presence of cysteine or methionine.

PubMed

Sreekumar, R; Al-Attabi, Z; Deeth, H C; Turner, M S

2009-06-01

To investigate the abilities of various probiotic bacteria to produce volatile sulfur compounds (VSCs) relevant to food flavour and aroma. Probiotic strains (Lactobacillus acidophilus NCFM, Lactobacillus plantarum 299v, Lactobacillus rhamnosus GG, Lactobacillus reuteri ATCC55730 and L. reuteri BR11), Lactobacillus delbrueckii ATCC4797, L. plantarum ATCC14917 and Lactococcus lactis MG1363 were incubated with either cysteine or methionine. Volatile compounds were captured, identified and quantified using a sensitive solid-phase microextraction (SPME) technique combined with gas chromatography coupled to a pulsed flame photometric detector (SPME/GC/PFPD). Several VSCs were identified including H(2)S, methanethiol, dimethyldisulfide and dimethyltrisulfide. The VSC profiles varied substantially for different strains of L. plantarum and L. reuteri and it was found that L. reuteri ATCC55730 and L. lactis MG1363 produced the lowest levels of VSCs (P < 0.05). Levels of VSCs generated by bacteria were found to be equivalent to, or higher than, that found in commercial cheeses. Several probiotic strains are able to generate considerable levels of VSCs and substantial variations in VSC generating potential exists between different strains from the same species. This study demonstrates that probiotic bacteria are able to efficiently generate important flavour and aroma compounds and therefore has implications for the development of probiotic containing foods.

Growth Inhibitory, Bactericidal, and Morphostructural Effects of Dehydrocostus Lactone from Magnolia sieboldii Leaves on Antibiotic-Susceptible and -Resistant Strains of Helicobacter pylori

PubMed Central

Lee, Hyun-Kyung; Song, Ha Eun; Lee, Haeng-Byung; Kim, Cheol-Soo; Koketsu, Mamoru; Thi My Ngan, Luong; Ahn, Young-Joon

2014-01-01

Helicobacter pylori is associated with various diseases of the upper gastrointestinal tract, such as gastric inflammation and duodenal and gastric ulcers. The aim of the study was to assess anti-H. pylori effects of the sesquiterpene lactone dehydrocostus lactone (DCL) from Magnolia sieboldii leaves, compared to commercial pure DCL, two previously known sesquiterpene lactones (costunolide and parthenolide), (–)-epigallocatechin gallate, and four antibiotics. The antibacterial activity of natural DCL toward antibiotic-susceptible H. pylori ATCC 700392 and H. pylori ATCC 700824 strains (MIC, 4.9 and 4.4 mg/L) was similar to that of commercial DCL and was more effective than costunolide, parthenolide, and EGCG. The activity of DCL was slightly lower than that of metronidazole (MIC, 1.10 and 1.07 mg/L). The antibacterial activity of DCL was virtually identical toward susceptible and resistant strains, even though resistance to amoxicillin (MIC, 11.1 mg/L for PED 503G strain), clarithromycin (49.8 mg/L for PED 3582GA strain), metronidazole (21.6 mg/L for H. pylori ATCC 43504 strain; 71.1 mg/L for 221 strain), or tetracycline (14.2 mg/L for B strain) was observed. This finding indicates that DCL and the antibiotics do not share a common mode of action. The bactericidal activity of DCL toward H. pylori ATCC 43504 was not affected by pH values examined (4.0–7.0). DCL caused considerable conversion to coccoid form (94 versus 49% at 8 and 4 mg/L of DCL for 48 h). The Western blot analysis revealed that urease subunits (UreA and UreB) of H. pylori ATCC 43504 were not affected by 10 mM of DCL, whereas UreA monomer band completely disappeared at 0.1 mM of (–)-epigallocatechin gallate. Global efforts to reduce the level of antibiotics justify further studies on M. sieboldii leaf-derived materials containing DCL as potential antibacterial products or a lead molecule for the prevention or eradication of drug-resistant H. pylori. PMID:24747984

Draft Genome Sequence of Escherichia coli K-12 (ATCC 10798).

PubMed

Dimitrova, Daniela; Engelbrecht, Kathleen C; Putonti, Catherine; Koenig, David W; Wolfe, Alan J

2017-07-06

Here, we present the draft genome sequence of Escherichia coli ATCC 10798. E. coli ATCC 10798 is a K-12 strain, one of the most well-studied model microorganisms. The size of the genome was 4,685,496 bp, with a G+C content of 50.70%. This assembly consists of 62 contigs and the F plasmid. Copyright © 2017 Dimitrova et al.

Draft Genome Sequence of Escherichia coli K-12 (ATCC 10798)

PubMed Central

Dimitrova, Daniela; Engelbrecht, Kathleen C.; Koenig, David W.; Wolfe, Alan J.

2017-01-01

ABSTRACT Here, we present the draft genome sequence of Escherichia coli ATCC 10798. E. coli ATCC 10798 is a K-12 strain, one of the most well-studied model microorganisms. The size of the genome was 4,685,496 bp, with a G+C content of 50.70%. This assembly consists of 62 contigs and the F plasmid. PMID:28684574

An investigation of virulence factors of Legionella pneumophila environmental isolates.

PubMed

Arslan-Aydoğdu, Elif Özlem; Kimiran, Ayten

Nine Legionella pneumophila strains isolated from cooling towers and a standard strain (L. pneumophila serogroup 1, ATCC 33152, Philadelphia 1) were analyzed and compared in terms of motility, flagella structure, ability to form biofilms, enzymatic activities (hemolysin, nucleases, protease, phospholipase A, phospholipase C, acid phosphatase, alkaline phosphatase and lipase), hemagglutination capabilities, and pathogenicity in various host cells (Acanthamoeba castellanii ATCC 30234, mouse peritoneal macrophages and human peripheral monocytes). All the isolates of bacteria appeared to be motile and polar-flagellated and possessed the type-IV fimbria. Upon the evaluation of virulence factors, isolate 4 was found to be the most pathogenic strain, while 6 out of the 9 isolates (the isolates 1, 2, 3, 4, 5, and 7) were more virulent than the ATCC 33152 strain. The different bacterial strains exhibited differences in properties such as adhesion, penetration and reproduction in the hosts, and preferred host type. To our knowledge, this is the first study to compare the virulence of environmental L. pneumophila strains isolated in Turkey, and it provides important information relevant for understanding the epidemiology of L. pneumophila. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Synthetic Peptides Derived from Bovine Lactoferricin Exhibit Antimicrobial Activity against E. coli ATCC 11775, S. maltophilia ATCC 13636 and S. enteritidis ATCC 13076.

PubMed

Huertas Méndez, Nataly De Jesús; Vargas Casanova, Yerly; Gómez Chimbi, Anyelith Katherine; Hernández, Edith; Leal Castro, Aura Lucia; Melo Diaz, Javier Mauricio; Rivera Monroy, Zuly Jenny; García Castañeda, Javier Eduardo

2017-03-12

Linear, dimeric, tetrameric, and cyclic peptides derived from lactoferricin B-containing non-natural amino acids and the RWQWR motif were synthesized, purified, and characterized using RP-HPLC, MALDI-TOF mass spectrometry, and circular dichroism. The antibacterial activity of peptides against Escherichia coli ATCC 11775, Stenotrophomonas maltophilia ATCC 13636, and Salmonella enteritidis ATCC 13076 was evaluated. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. The synthetic bovine lactoferricin exhibited antibacterial activity against E. coli ATCC 11775 and S. enteritidis ATCC 13076. The dimeric peptide (RRWQWR)₂K-Ahx exhibited the highest antibacterial activity against the tested bacterial strain. The monomeric, cyclic, tetrameric, and palindromic peptides containing the RWQWR motif exhibited high and specific activity against E. coli ATCC 11775. The results suggest that short peptides derived from lactoferricin B could be considered as potential candidates for the development of antibacterial agents against infections caused by E. coli .

Lactobacillus brantae sp. nov., isolated from faeces of Canada geese (Branta canadensis).

PubMed

Volokhov, Dmitriy V; Amselle, Megan; Beck, Brian J; Popham, David L; Whittaker, Paul; Wang, Hua; Kerrigan, Elizabeth; Chizhikov, Vladimir E

2012-09-01

Three strains of lactic acid bacteria (LAB) were isolated from the faeces of apparently healthy wild Canada geese (Branta canadensis) in 2010 by cultivating faecal LAB on Rogosa SL agar under aerobic conditions. These three isolates were found to share 99.9 % gene sequence similarity of their 16S rRNA, their 16S-23S intergenic transcribed spacer region (ITS), partial 23S rRNA, rpoB, rpoC, rpoA and pheS gene sequences. However, the three strains exhibited lower levels of sequence similarity of these genetic targets to all known LAB, and the phylogenetically closest species to the geese strains were Lactobacillus casei, Lactobacillus paracasei, Lactobacillus rhamnosus and Lactobacillus saniviri. In comparison to L. casei ATCC 393(T), L. paracasei ATCC 25302(T), L. rhamnosus ATCC 7469(T) and L. saniviri DSM 24301(T), the novel isolates reacted uniquely in tests for cellobiose, galactose, mannitol, citric acid, aesculin and dextrin, and gave negative results in tests for l-proline arylamidase and l-pyrrolydonyl-arylamidase, and in the Voges-Proskauer test. Biochemical tests for cellobiose, aesculin, galactose, gentiobiose, mannitol, melezitose, ribose, salicin, sucrose, trehalose, raffinose, turanose, amygdalin and arbutin could be used for differentiation between L. saniviri and the novel strains. On the basis of phenotypic and genotypic characteristics, and phylogenetic data, the three isolates represent a novel species of the genus Lactobacillus, for which the name Lactobacillus brantae sp. nov. is proposed. The type strain is SL1108(T) (= ATCC BAA-2142(T) = LMG 26001(T) = DSM 23927(T)) and two additional strains are SL1170 and SL60106.

Influence of rpoS mutations on the response of Salmonella enterica serovar Typhimurium to solar radiation.

PubMed

Oppezzo, Oscar J; Costa, Cristina S; Pizarro, Ramón A

2011-01-10

Salmonella enterica serovar Typhimurium is an important pathogen, and exhibits considerable resistance to the lethal effects of solar radiation. To evaluate the involvement of the RpoS transcription factor in the defense mechanisms of this organism, the sunlight response of a wild type strain (ATCC14028) was compared with that of an rpoS mutant, which exhibited increased sensitivity. Kinetics of cell death was complex in both strains, probably due to the presence of a variety of targets for the radiation. When ultraviolet radiation was excluded from the incident sunlight, lethal effects were abolished independently of the allelic state of rpoS. Reduction of oxygen concentration in the irradiation medium provided moderate protection to ATCC14028, but notably improved survival of the mutant. Similar assays were developed with another S. enterica strain (DA1468), which is a derivative of strain LT2 and produces low levels of RpoS. In this strain the loss of viability reveals the dependence on solar ultraviolet and oxygen concentration found for ATCC14028, but radiation resistance was slightly reduced. Increased sensitivity was observed in an rpoS mutant derived from DA1468, indicating that RpoS functions related to photoprotection are conserved in this strain. In addition, notable differences in the shape of the survival curves obtained for mutants derived from ATCC14028 and DA1468 were found, suggesting that genes beyond RpoS control are relevant in the sunlight response of these mutants. Copyright © 2010 Elsevier B.V. All rights reserved.

Design of antisense RNA constructs for downregulation of the acetone formation pathway of Clostridium acetobutylicum.

PubMed

Tummala, Seshu B; Welker, Neil E; Papoutsakis, Eleftherios T

2003-03-01

We investigated the effect of antisense RNA (asRNA) structural properties on the downregulation efficacy of enzymes in the acetone-formation pathway (acetoacetate decarboxylase [AADC] and coenzyme A-transferase [CoAT]) of Clostridium acetobutylicum strain ATCC 824. First, we generated three strains, C. acetobutylicum ATCC 824 (pADC38AS), 824(pADC68AS), and 824(pADC100AS), which contain plasmids that produce asRNAs of various lengths against the AADC (adc) transcript. Western analysis showed that all three strains exhibit low levels of AADC compared to the plasmid control [ATCC 824(pSOS95del)]. By using computational algorithms, the three different asRNAs directed toward AADC, along with previously reported clostridial asRNAs, were examined for structural features (free nucleotides and components). When the normalized metrics of these structural features were plotted against percent downregulation, only the component/nucleotide ratio correlated well with in vivo asRNA effectiveness. Despite the significant downregulation of AADC in these strains, there were no concomitant effects on acetone formation. These findings suggest that AADC does not limit acetone formation and, thus, we targeted next the CoAT. Using the component/nucleotide ratio as a selection parameter, we developed three strains [ATCC 824 (pCTFA2AS), 824(pCTFB1AS), and 824(pCOAT11AS)] which express asRNAs to downregulate either or both of the CoAT subunits. Compared to the plasmid control strain, these strains produced substantially low levels of acetone and butanol and Western blot analyses showed significantly low levels of both CoAT subunits. These results show that CoAT is the rate-limiting enzyme in acetone formation and strengthen the hypothesis that the component/nucleotide ratio is a predictive indicator of asRNA effectiveness.

Design of Antisense RNA Constructs for Downregulation of the Acetone Formation Pathway of Clostridium acetobutylicum

PubMed Central

Tummala, Seshu B.; Welker, Neil E.; Papoutsakis, Eleftherios T.

2003-01-01

We investigated the effect of antisense RNA (asRNA) structural properties on the downregulation efficacy of enzymes in the acetone-formation pathway (acetoacetate decarboxylase [AADC] and coenzyme A-transferase [CoAT]) of Clostridium acetobutylicum strain ATCC 824. First, we generated three strains, C. acetobutylicum ATCC 824 (pADC38AS), 824(pADC68AS), and 824(pADC100AS), which contain plasmids that produce asRNAs of various lengths against the AADC (adc) transcript. Western analysis showed that all three strains exhibit low levels of AADC compared to the plasmid control [ATCC 824(pSOS95del)]. By using computational algorithms, the three different asRNAs directed toward AADC, along with previously reported clostridial asRNAs, were examined for structural features (free nucleotides and components). When the normalized metrics of these structural features were plotted against percent downregulation, only the component/nucleotide ratio correlated well with in vivo asRNA effectiveness. Despite the significant downregulation of AADC in these strains, there were no concomitant effects on acetone formation. These findings suggest that AADC does not limit acetone formation and, thus, we targeted next the CoAT. Using the component/nucleotide ratio as a selection parameter, we developed three strains [ATCC 824 (pCTFA2AS), 824(pCTFB1AS), and 824(pCOAT11AS)] which express asRNAs to downregulate either or both of the CoAT subunits. Compared to the plasmid control strain, these strains produced substantially low levels of acetone and butanol and Western blot analyses showed significantly low levels of both CoAT subunits. These results show that CoAT is the rate-limiting enzyme in acetone formation and strengthen the hypothesis that the component/nucleotide ratio is a predictive indicator of asRNA effectiveness. PMID:12618456

Searching for Beta-Haemolysin hlb Gene in Staphylococcus pseudintermedius with Species-Specific Primers.

PubMed

Kmieciak, Wioletta; Szewczyk, Eligia M; Ciszewski, Marcin

2016-07-01

The paper presents an analysis of 51 Staphylococcus pseudintermedius clinically isolated strains from humans and from animals. Staphylococcus pseudintermedius strains' ability to produce β-haemolysin was evaluated with phenotypic methods (hot-cold effect, reverse CAMP test). In order to determine the hlb gene presence (coding for β-haemolysin) in a genomic DNA, PCR reactions were conducted with two different pairs of primers: one described in the literature for Staphylococcus aureus and recommended for analysing SIG group staphylococci and newly designed one in CLC Main Workbench software. Only reactions with newly designed primers resulted in product amplification, the presence of which was fully compatible with the results of phenotypic β-haemolysin test. Negative results for S. aureus and S. intermedius reference ATCC strains suggest that after further analysis the fragment of hlb gene amplified with primers described in this study might be included in the process of S. pseudintermedius strains identification.

Impact of UVA pre-radiation on UVC disinfection performance: Inactivation, repair and mechanism study.

PubMed

Xiao, Y; Chu, X N; He, M; Liu, X C; Hu, J Y

2018-05-15

Ultraviolet (UV) light emission diode (LED), which is mercury free and theoretically more energy efficient, has now become an alternative to conventional UV lamps in water disinfection industry. In this research, the disinfection performance of a novel sequential process, UVA 365nm LED followed by UVC 265nm LED (UVA-UVC), was evaluated. The results revealed that the responses of different bacterial strains to UVA-UVC varied. Coupled with appropriate dosages of UVC, a 20 min UVA pre-radiation provided higher inactivations (log inactivation) of E. coli ATCC 11229, 15597 and 700891 by 1.2, 1.4 and 1.2 times, respectively than the sum of inactivations by UVA alone and UVC alone. On the contrary, the inactivation of E. coli ATCC 25922, the most UVC sensitive strain, decreased from 3 log to 1.8 log after UVA pre-radiation. A 30 min UVA pre-radiation did not affect the photo repair capacity of the four strains (n = 23, p > 0.1), but their dark repair ability was significantly inhibited (n = 14, p < 0.05). Mechanism study was conducted for two representative strains, E. coli ATCC 15597 and 25922 to understand the observed effect. The hypothesis that UVA pre-radiation promoted the yield of reactive oxygen species (ROS) was rejected. ELISA results indicated that 18% more cyclobutane pyrimidine dimers (CPD) were formed in E. coli ATCC 15597 with UVA pre-radiation (n = 3, p < 0.01), however, the CPD levels of E. coli ATCC 25922 was the same with or without UVA pre-radiation (n = 3, p > 0.01). Considering the results of both dark repair and CPD formation, it was concluded that the increased UV sensitivity of E. coli 15597 was originated from the increased CPD. For E. coli ATCC 25922, the enhanced UV resistance was attributed to the strain's adoption of a survival strategy, translesion DNA synthesis (TLS), when triggered by UVA pre-radiation. The study on UmuD protein, which is a key protein during TLS, confirmed this hypothesis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Survival of Acinetobacter baumannii on dry surfaces.

PubMed Central

Wendt, C; Dietze, B; Dietz, E; Rüden, H

1997-01-01

Acinetobacter spp. have frequently been reported to be the causative agents of hospital outbreaks. The circumstances of some outbreaks demonstrated the long survival of Acinetobacter in a dry, inanimate environment. In laboratory experiments, we compared the abilities of five Acinetobacter baumannii strains, three Acinetobacter sp. strains from the American Type Culture Collection (ATCC), one Escherichia coli ATCC strain, and one Enterococcus faecium ATCC strain to survive under dry conditions. Bacterial solutions of the 10 strains were inoculated onto four different material samples (ceramic, polyvinyl chloride, rubber, and stainless steel) and stored under defined conditions. We investigated the bacterial counts of the material samples immediately after inoculation, after drying, and after 4 h, 1 day, and 1, 2, 4, 8, and 16 weeks of storage. A statistical model was used to distribute the 40 resulting curves among four types of survival curves. The type of survival curve was significantly associated with the bacterial strain but not with the material. The ability of the A. baumannii strains to survive under dry conditions varied greatly and correlated well with the source of the strain. Strains isolated from dry sources survived better than those isolated from wet sources. An outbreak strain that had caused hospital-acquired respiratory tract infections survived better than the strains from wet sources, but not as well as strains from dry sources. Resistance to dry conditions may promote the transmissibility of a strain, but it is not sufficient to make a strain an epidemic one. However, in the case of an outbreak, sources of Acinetobacter must be expected in the dry environment. PMID:9163451

Virulent and Vaccine Strains of Streptococcus equi ssp. zooepidemicus Have Different Influences on Phagocytosis and Cytokine Secretion of Macrophages.

PubMed

Jie, Peng; Zhe, Ma; Chengwei, Hua; Huixing, Lin; Hui, Zhang; Chengping, Lu; Hongjie, Fan

2017-01-06

Swine streptococcosis is a significant threat to the Chinese pig industry, and Streptococcus equi ssp. zooepidemicus (SEZ) is one of the major pathogens. SEZ ATCC35246 is a classical virulent strain, while SEZ ST171 is a Chinese attenuated vaccine strain. In this study, we employed stable isotope labeling by amino acids in cell culture and liquid chromatography-mass spectrometry (LC-MS) to determine the differential response of macrophages to infection by these two strains. Eighty-seven upregulated proteins and 135 downregulated proteins were identified. The proteomic results were verified by real-time polymerase chain reaction for 10 chosen genes and Western blotting for three proteins. All differentially abundant proteins were analyzed for their Gene Ontology and Kyoto Encyclopedia of Genes and Genomes annotations. Certain downregulated proteins were associated with immunity functions, and the upregulated proteins were related to cytomembrane and cytoskeleton regulation. The phagocytosis rate and cytokine genes transcription in Raw264.7 cells during SEZ ATCC35246 and ST171 infection were detected to confirm the bioinformatics results. These results showed that different effects on macrophage phagocytosis and cytokine expression might explain the different phenotypes of SEZ ATCC35246 and ST171 infection. This research provided clues to the mechanisms of host immunity responses to SEZ ST171and SEZ ATCC35246, which could identify potential therapy and vaccine development targets.

Molecular biological researches of Kuro-Koji molds, their classification and safety.

PubMed

Yamada, Osamu; Takara, Ryo; Hamada, Ryoko; Hayashi, Risa; Tsukahara, Masatoshi; Mikami, Shigeaki

2011-09-01

To assess the position of Kuro-Koji molds in black Aspergillus, we performed sequence analysis of approximately 2500 nucleotides of partial gene fragments, such as histone 3, on a total of 57 Aspergillus strains, including Aspergillus kawachii NBRC 4308, 12 Kuro-Koji molds isolated from awamori breweries in Japan, Aspergillus niger ATCC 1015, and A. tubingensis ATCC10550. Sequence results showed that all black Aspergillus strains could be classified into 3 types, type N which includes A. niger ATCC 1015, type T which includes A. tubingensis ATCC 10550, and type L which includes A. kawachii NBRC 4308. Phylogenetic analysis showed these three types belong to different clusters. All 12 Kuro-Koji molds isolated from awamori breweries were classified as type L, thus we concluded type L represents the industrial Kuro-Koji molds. We found all type L strains lack the An15g07920 gene which is required for ochratoxin A biosynthesis in black Aspergillus. This sequence is present in the genome of A. niger CBS 513.88 and has homology to the polyketide synthase fragment of A. ochraceus which is involved in ochratoxin A biosynthesis. Based on the industrial importance and the safety of Kuro-Koji molds, we propose to classify the type L strains as Aspergillus luchuensis, as initially reported by Dr. Inui. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Bactericidal activity of culture fluid components of Lactobacillus fermentum strain 90 TS-4 (21) clone 3, and their capacity to modulate adhesion of Candida albicans yeast-like fungi to vaginal epithelial cells.

PubMed

Anokhina, I V; Kravtsov, E G; Protsenko, A V; Yashina, N V; Yermolaev, A V; Chesnokova, V L; Dalin, M V

2007-03-01

Antagonistic activities of L. fermentum strain 90 TS-4 (21), L. casei ATCC 27216, and L. acidophilus ATCC 4356 and bactericidal activity of lactobacillus culture fluid towards E. coli strain K12, S. aureus, and S. epidermidis test cultures were studied. The bactericidal effect of L. fermentum strain 90 TS-4 (21) clone 3 culture fluid preparation (pH 6.0) on the test cultures was dose-dependent. Adhesion of C. albicans yeast-like fungi to vaginal epitheliocytes was more pronounced for strains isolated from women with asymptomatic infection than for strains isolated from women with manifest forms. L. fermentum strain 90 TS-4 (21) clone 3 culture fluid preparation modulated adhesion of yeast-like fungi only if the fungal strain was initially highly adherent.

Correlation of Klebsiella pneumoniae Comparative Genetic Analyses with Virulence Profiles in a Murine Respiratory Disease Model

PubMed Central

Tam, Hok-Hei; Yan, Pearlly; Pfeffer, Tia L.; Bundschuh, Ralf; Warawa, Jonathan M.

2014-01-01

Klebsiella pneumoniae is a bacterial pathogen of worldwide importance and a significant contributor to multiple disease presentations associated with both nosocomial and community acquired disease. ATCC 43816 is a well-studied K. pneumoniae strain which is capable of causing an acute respiratory disease in surrogate animal models. In this study, we performed sequencing of the ATCC 43816 genome to support future efforts characterizing genetic elements required for disease. Furthermore, we performed comparative genetic analyses to the previously sequenced genomes from NTUH-K2044 and MGH 78578 to gain an understanding of the conservation of known virulence determinants amongst the three strains. We found that ATCC 43816 and NTUH-K2044 both possess the known virulence determinant for yersiniabactin, as well as a Type 4 secretion system (T4SS), CRISPR system, and an acetonin catabolism locus, all absent from MGH 78578. While both NTUH-K2044 and MGH 78578 are clinical isolates, little is known about the disease potential of these strains in cell culture and animal models. Thus, we also performed functional analyses in the murine macrophage cell lines RAW264.7 and J774A.1 and found that MGH 78578 (K52 serotype) was internalized at higher levels than ATCC 43816 (K2) and NTUH-K2044 (K1), consistent with previous characterization of the antiphagocytic properties of K1 and K2 serotype capsules. We also examined the three K. pneumoniae strains in a novel BALB/c respiratory disease model and found that ATCC 43816 and NTUH-K2044 are highly virulent (LD50<100 CFU) while MGH 78578 is relatively avirulent. PMID:25203254

Characterization of Micrococcus strains isolated from indoor air.

PubMed

Kooken, Jennifer M; Fox, Karen F; Fox, Alvin

2012-02-01

The characterization of microbes, such as opportunists and pathogens (e.g., methicillin resistant Staphylococcus aureus [MRSA]), in indoor air is important for understanding disease transmission from person-to-person. Common genera found in the human skin microbiome include Micrococcus and Staphylococcus, but there only a limited number of tests to differentiate these genera and/or species. Both genera are believed to be released into indoor air from the shedding of human skin and are morphologically difficult to distinguish. In the current work, after the extraction of proteins from micrococci and the separation of these proteins on one dimensional electrophoretic gels, tryptic peptides were analyzed by MALDI TOF MS and the mass profiles compared with those of a reference strain (ATCC 4698). The results confirmed that all strains were consistent in identity with Micrococcus luteus. Copyright © 2011 Elsevier Ltd. All rights reserved.

Characterization of Micrococcus strains isolated from indoor air

PubMed Central

Kooken, Jennifer M.; Fox, Karen F.; Fox, Alvin

2014-01-01

The characterization of microbes, such as of opportunists and pathogens (e.g. methicillin resistant Staphylococcus aureus [MRSA]), in indoor air is important for understanding disease transmission from person-to-person. Common genera found in the human skin microbiome include Micrococcus and Staphylococcus, but there only a limited number of tests to differentiate these genera and/or species. Both genera are believed to be released into indoor air from the shedding of human skin and are morphologically difficult to distinguish. In the current work, after the extraction of proteins from micrococci and the separation of these proteins on one dimensional electrophoretic gels, tryptic peptides were analyzed by MALDI TOF MS and the mass profiles compared with those of a reference strain (ATCC 4698). The results confirmed that all strains were consistent in identity with Micrococcus luteus. PMID:21963944

Production of L-lactic acid from metabolically engineered strain of Enterobacter aerogenes ATCC 29007.

PubMed

Thapa, Laxmi Prasad; Lee, Sang Jun; Park, Chulhwan; Kim, Seung Wook

2017-07-01

In this study, L-lactic acid production was investigated from metabolically engineered strain of E. aerogenes ATCC 29007. The engineered strain E. aerogenes SUMI01 (Δpta) was generated by the deletion of phosphate acetyltransferase (pta) gene from the chromosome of E. aerogenes ATCC 29007 and deletion was confirmed by colony PCR. Under the optimized fermentation conditions, at 37°C and pH 6 for 84h, the L-lactic acid produced by engineered strain E. aerogenes SUMI01 (Δpta) in flask fermentation using 100g/L mannitol as the carbon source was 40.05g/L as compared to that of the wild type counterpart 20.70g/L. At the end of the batch fermentation in bioreactor the production of L-lactic acid reached to 46.02g/L and yield was 0.41g/g by utilizing 112.32g/L mannitol. This is the first report regarding the production of L-lactic acid from Enterobacter species. We believe that this result may provide valuable guidelines for further engineering Enterobacter strain for the improvement of L-lactic acid production. Copyright © 2017 Elsevier Inc. All rights reserved.

Stability of free and encapsulated Lactobacillus acidophilus ATCC 4356 in yogurt and in an artificial human gastric digestion system.

PubMed

Ortakci, F; Sert, S

2012-12-01

The objective of this study was to determine the effect of encapsulation on survival of probiotic Lactobacillus acidophilus ATCC 4356 (ATCC 4356) in yogurt and during artificial gastric digestion. Strain ATCC 4356 was added to yogurt either encapsulated in calcium alginate or in free form (unencapsulated) at levels of 8.26 and 9.47 log cfu/g, respectively, and the influence of alginate capsules (1.5 to 2.5mm) on the sensorial characteristics of yogurts was investigated. The ATCC 4356 strain was introduced into an artificial gastric solution consisting of 0.08 N HCl (pH 1.5) containing 0.2% NaCl or into artificial bile juice consisting of 1.2% bile salts in de Man, Rogosa, and Sharpe broth to determine the stability of the probiotic bacteria. When incubated for 2h in artificial gastric juice, the free ATCC 4356 did not survive (reduction of >7 log cfu/g). We observed, however, greater survival of encapsulated ATCC 4356, with a reduction of only 3 log cfu/g. Incubation in artificial bile juice (6 h) did not significantly affect the viability of free or encapsulated ATCC 4356. Moreover, statistically significant reductions (~1 log cfu/g) of both free and encapsulated ATCC 4356 were observed during 4-wk refrigerated storage of yogurts. The addition of probiotic cultures in free or alginate-encapsulated form did not significantly affect appearance/color or flavor/odor of the yogurts. However, significant deficiencies were found in body/texture of yogurts containing encapsulated ATCC 4356. We concluded that incorporation of free and encapsulated probiotic bacteria did not substantially change the overall sensory properties of yogurts, and encapsulation in alginate using the extrusion method greatly enhanced the survival of probiotic bacteria against an artificial human gastric digestive system. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Polaribacter gen. nov., with three new species, P. irgensii sp. nov., P. franzmannii sp. nov. and P. filamentus sp. nov., gas vacuolate polar marine bacteria of the Cytophaga-Flavobacterium-Bacteroides group and reclassification of 'Flectobacillus glomeratus' as Polaribacter glomeratus comb. nov

NASA Technical Reports Server (NTRS)

Gosink, J. J.; Woese, C. R.; Staley, J. T.

1998-01-01

Several psychrophilic, gas vacuolate strains of the Cytophage-Flavobacterium-Bacteroides (CFB) phylogenetic group were isolated from sea ice and water from the Arctic and the Antarctic. The closest taxonomically defined species by 16S rRNA sequence analysis is 'Flectobacillus glomeratus'. However, 'Flc. glomeratus' is phylogenetically distant from the Flectobacillus type species, Flc. major. On the basis of phenotypic, genotypic and 16S rRNA sequence analyses we propose a new genus, Polaribacter, with three new species, Polaribacter irgensii strain 23-P (ATCC 700398), Polaribacter franzmannii strain 301 (ATCC 700399) and Polaribacter filamentus strain 215 (ATCC 700397). P. filamentus is the type species of the genus. None of these species exhibits a cosmopolitan or bipolar distribution. This is the first taxonomic description of gas vacuolate bacteria in the CFB group. Additionally, we propose that 'Flc. glomeratus' be reclassified to the genus Polaribacter as P. glomeratus, comb. nov.

Induction of hairy roots by various strains of Agrobacterium rhizogenes in different types of Capsicum species explants.

PubMed

Md Setamam, Nursuria; Jaafar Sidik, Norrizah; Abdul Rahman, Zainon; Che Mohd Zain, Che Radziah

2014-06-30

Capsicum annuum and Capsicum frutescens, also known as "chilies", belong to the Solanaceae family and have tremendous beneficial properties. The application of hairy root culture may become an alternative method for future development of these species by adding value, such as by increasing secondary metabolites and improving genetic and biochemical stability compared with normal Capsicum plants. Therefore, in this research, different types of explants of both species were infected with various Agrobacterium rhizogenes strains to provide more information about the morphology and induction efficiency of hairy roots. After 2 weeks of in vitro seed germination, young seedling explants were cut into three segments; the cotyledon, hypocotyl, and radical. Then, the explants were co-cultured with four isolated A. rhizogenes strains in Murashige & Skoog culture media (MS) containing decreasing carbenicillin disodium concentrations for one month. In this experiment, thick and short hairy roots were induced at all induction sites of C. annuum while thin, elongated hairy roots appeared mostly at wound sites of C. frutescens. Overall, the hairy root induction percentages of C. frutescens were higher compared with C. annuum. Hairy root initiation was observed earliest using radicles (1st week), followed by cotyledons (2nd week), and hypocotyls (3rd week). Cotyledon explants of both species had the highest induction frequency with all strains compared with the other explants types. Strains ATCC 13333 and ATCC 15834 were the most favourable for C. frutescens while ATCC 43056 and ATCC 43057 were the most favourable for C. annuum. The interactions between the different explants and strains showed significant differences with p-values < 0.0001 in both Capsicum species. Both Capsicum species were amenable to A. rhizogenes infection and hairy root induction is recommended for use as an alternative explants in future plant-based studies.

Essential oils and herbal extracts as antimicrobial agents in cosmetic emulsion.

PubMed

Herman, Anna; Herman, Andrzej Przemysław; Domagalska, Beata Wanda; Młynarczyk, Andrzej

2013-06-01

The cosmetic industry adapts to the needs of consumers seeking to limit the use of preservatives and develop of preservative-free or self-preserving cosmetics, where preservatives are replaced by raw materials of plant origin. The aim of study was a comparison of the antimicrobial activity of extracts (Matricaria chamomilla, Aloe vera, Calendula officinalis) and essential oils (Lavandulla officinallis, Melaleuca alternifolia, Cinnamomum zeylanicum) with methylparaben. Extracts (2.5 %), essential oils (2.5 %) and methylparaben (0.4 %) were tested against Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, Candida albicans ATCC 14053. Essentials oils showed higher inhibitory activity against tested microorganism strain than extracts and methylparaben. Depending on tested microorganism strain, all tested extracts and essential oils show antimicrobial activity 0.8-1.7 and 1-3.5 times stronger than methylparaben, respectively. This shows that tested extracts and essential oils could replace use of methylparaben, at the same time giving a guarantee of microbiological purity of the cosmetic under its use and storage.

Study of probiotic potential of four wild Lactobacillus rhamnosus strains.

PubMed

Tuo, Yanfeng; Zhang, Weiqin; Zhang, Lanwei; Ai, Lianzhong; Zhang, Yingchun; Han, Xue; Yi, Huaxi

2013-06-01

The four wild Lactobacillus rhamnosus strains were examined in vitro for resistance to simulated gastro and intestinal juices, adhesion to HT-29 cells, antagonistic activity against enteric pathogens and immunomodulating activity. The strains L. rhamnosus SB5L, J5L and IN1L were able to survive in simulated gastro juice while the strain L. rhamnosus SB31L lost viability exposed to simulated gastro juice for 3 h. The four strains had high viability in simulated small intestinal juice with little loss (<1.0 cycle reduction). The strains SB5L, J5L and IN1L antagonized against Escherichia coli ATCC 25922, Salmonella enterica serovar Typhimurium ATCC 14028, Shigella sonnei ATCC 25931. The strain L. rhamnosus IN1L had the highest adhesive capability to HT-29 cells in vitro (251 bacteria cells per 100 HT-29 cells) compared to the other three L. rhamnosus strains. The live bacteria, cell wall and DNA of the four L. rhamnosus induced the secretion of pro-inflammatory cytokines IL-12 (p70), IFN-γ and TNF-α by human peripheral blood mononuclear cells (PBMCs). The levels of IL-12 (p70), IFN-γ and TNF-α produced by stimulated PBMCs were significantly higher (P < 0.05) than those of the control. Those data indicated that the four L. rhamnosus strains have the potential as the probiotic for human being use, although further studies are still needed. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Analysis of strain-specific genes in glutamic acid-producing Corynebacterium glutamicum ssp. lactofermentum AJ 1511.

PubMed

Nishio, Yousuke; Koseki, Chie; Tonouchi, Naoto; Matsui, Kazuhiko; Sugimoto, Shinichi; Usuda, Yoshihiro

2017-07-11

Strains of the bacterium, Corynebacterium glutamicum, are widely used for the industrial production of L-glutamic acid and various other substances. C. glutamicum ssp. lactofermentum AJ 1511, formerly classified as Brevibacterium lactofermentum, and the closely related C. glutamicum ATCC 13032 have been used as industrial strains for more than 50 years. We determined the whole genome sequence of C. glutamicum AJ 1511 and performed genome-wide comparative analysis with C. glutamicum ATCC 13032 to determine strain-specific genetic differences. This analysis revealed that the genomes of the two industrial strains are highly similar despite the phenotypic differences between the two strains. Both strains harbored unique genes but gene transpositions or inversions were not observed. The largest unique region, a 220-kb AT-rich region located between 1.78 and 2.00 Mb position in C. glutamicum ATCC 13032 genome, was missing in the genome of C. glutamicum AJ 1511. The next two largest unique regions were present in C. glutamicum AJ 1511. The first region (413-484 kb position) contains several predicted transport proteins, enzymes involved in sugar metabolism, and transposases. The second region (1.47-1.50 Mb position) encodes restriction modification systems. A gene predicted to encode NADH-dependent glutamate dehydrogenase, which is involved in L-glutamate biosynthesis, is present in C. glutamicum AJ 1511. Strain-specific genes identified in this study are likely to govern phenotypes unique to each strain.

Comparative genomics of citric-acid producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andersen, Mikael R.; Salazar, Margarita; Schaap, Peter

2011-06-01

The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compels additional exploration. We therefore undertook whole genome sequencing of the acidogenic A. niger wild type strain (ATCC 1015), and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence and half the telomeric regionsmore » have been elucidated. Moreover, sequence information from ATCC 1015 was utilized to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 megabase of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis revealed up-regulation of the electron transport chain, specifically the alternative oxidative pathway in ATCC 1015, while CBS 513.88 showed significant up regulation of genes associated with biosynthesis of amino acids that are abundant in glucoamylase A, tRNA-synthases and protein transporters.« less

Radiation survival of two nalidixic acid resistant strains of Salmonella typhimurium in various media

NASA Astrophysics Data System (ADS)

Shamsuzzaman, Kazi; Goodwin, Marlene; George, Ian; Singh, Harwant

Radiation doses required for 90% inactivation, the D10 values, have been determined for two nalidixic acid-resistant strains of Salmonella typhimurium, Nal R ATCC 13311 and K1-2B, in different media. The D10 values were 0.20, 0.57 and 0.53 kGy for the ATCC 13311 strain, and were 0.21, 0.4 and 0.32 kGy for the K1-2B strain, in phosphate buffer, in nutrient broth and on chicken drumsticks, respectively. Since these two strains have radiation sensitivity similar to several Salmonella serotypes reported in the literature, they are good indicator organisms for use in studies on the effect of irradiation on Salmonella in foods that might frequently be contaminated with such organisms.

Investigation of the Amycolatopsis sp. strain ATCC 39116 vanillin dehydrogenase and its impact on the biotechnical production of vanillin.

PubMed

Fleige, Christian; Hansen, Gunda; Kroll, Jens; Steinbüchel, Alexander

2013-01-01

The actinomycete Amycolatopsis sp. strain ATCC 39116 is capable of synthesizing large amounts of vanillin from ferulic acid, which is a natural cell wall component of higher plants. The desired intermediate vanillin is subject to undesired catabolism caused by the metabolic activity of a hitherto unknown vanillin dehydrogenase (VDH(ATCC 39116)). In order to prevent the oxidation of vanillin to vanillic acid and thereby to obtain higher yields and concentrations of vanillin, the responsible vanillin dehydrogenase in Amycolatopsis sp. ATCC 39116 was investigated for the first time by using data from our genome sequence analysis and further bioinformatic approaches. The vdh gene was heterologously expressed in Escherichia coli, and the encoded vanillin dehydrogenase was characterized in detail. VDH(ATCC 39116) was purified to apparent electrophoretic homogeneity and exhibited NAD(+)-dependent activity toward vanillin, coniferylaldehyde, cinnamaldehyde, and benzaldehyde. The enzyme showed its highest level of activity toward vanillin at pH 8.0 and at a temperature of 44°C. In a next step, a precise vdh deletion mutant of Amycolatopsis sp. ATCC 39116 was generated. The mutant lost its ability to grow on vanillin and did not show vanillin dehydrogenase activity. A 2.3-times-higher vanillin concentration and a substantially reduced amount of vanillic acid occurred with the Amycolatopsis sp. ATCC 39116 Δvdh::Km(r) mutant when ferulic acid was provided for biotransformation in a cultivation experiment on a 2-liter-bioreactor scale. Based on these results and taking further metabolic engineering into account, the Amycolatopsis sp. ATCC 39116 Δvdh::Km(r) mutant represents an optimized and industrially applicable platform for the biotechnological production of natural vanillin.

Complete Genome Sequence of Thiostrepton-Producing Streptomyces laurentii ATCC 31255

PubMed Central

Fujino, Yasuhiro; Nagayoshi, Yuko; Ohshima, Toshihisa; Ogata, Seiya

2016-01-01

Streptomyces laurentii ATCC 31255 produces thiostrepton, a thiopeptide class antibiotic. Here, we report the complete genome sequence for this strain, which contains a total of 8,032,664 bp, 7,452 predicted coding sequences, and a G+C content of 72.3%. PMID:27257211

Lipoquinones of some spore-forming rods, lactic-acid bacteria and actinomycetes.

PubMed

Hess, A; Holländer, R; Mannheim, W

1979-11-01

The respiratory quinones of 73 strains of Gram-positive bacteria including spore-forming rods, lactic-acid bacteria and actinomyctes were examined. Menaquinones with seven isoprenoid units (MK-7) were the main quinone type found in representatives of the genus Bacillus and in Sporolactobacillus inulinus. However, a strain of B. thuringiensis produced MK-8 in addition to MK-7, and strains of B. lentus and B. pantothenticus appeared to produce MK-9 and MK-8, respectively, with no MK-7. In the clostridia and lactic-acid bacteria, no quinones were found, except in Pediococcus cerevisiae NCTC 8066 and Lactobacillus casei subsp. rhamnosus ATCC 7469, which contained menaquinones, and Streptococcus faecalis NCTC 775 and HIM 478-1, which contained demethylmenaquinones, in relatively low concentrations. Menaquinones were also found in the actinomycetes (except Actinomyces odontolyticus and Bifidobacterium bifidum which did not produce any quinones) and in Protaminobacter alboflavus ATCC 8458, the so-called Actinobacillus actinoides ATCC 15900 and Noguchia granulosis NCTC 10559.

Complete genome sequence of Anabaena variabilis ATCC 29413

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thiel, Teresa; Pratte, Brenda S.; Zhong, Jinshun

2013-01-01

Anabaena variabilis ATCC 29413 is a filamentous, heterocyst-forming cyanobacterium that has served as a model organism, with an extensive literature extending over 40 years. The strain has three distinct nitrogenases that function under different environmental conditions and is capable of photoautotrophic growth in the light and true heterotrophic growth in the dark using fructose as both carbon and energy source. While this strain was first isolated in 1964 in Mississippi and named Ana-baena flos-aquae MSU A-37, it clusters phylogenetically with cyanobacteria of the genus Nostoc. The strain is a moderate thermophile, growing well at approximately 40 C. Here we providemore » some additional characteristics of the strain, and an analysis of the complete genome sequence.« less

Synthesis and Bioactivity Evaluation of Novel 2-Salicyloylbenzofurans as Antibacterial Agents.

PubMed

Phan, Phuong-Thuy T; Nguyen, Thu-Trang T; Nguyen, Hong-Nhung T; Le, Bao-Khanh N; Vu, Thao T; Tran, Dong C; Pham, Tuan-Anh N

2017-04-25

In order to discover new antibacterial agents, series of 2-salicyloylbenzofuran derivatives were designed, synthesized and evaluated for their antibacterial activities against three Gram-(+) strains (methicillin-sensitive Staphylococcus aureus (MSSA) ATCC 29213, methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300, and Streptococcus faecalis ( S. faecalis ) ATCC 29212) and one Gram-(-) strain ( Escherichia coli (E. coli) ATCC 25922). The 2-salicyloylbenzofuran heterocycles were generated by Rap-Stoermer condensation of salicylaldehydes with phenacyl bromides and then converted to diverse O -ether derivatives by Williamson synthesis. The targeted products were screened for in vitro qualitative (zone of inhibition) and quantitative (MIC) antibacterial activities by agar well diffusion assay and agar dilution method. Amongst the compounds, those bearing carboxylic acid functional group were found to exhibit reasonable activity against Gram-(+) bacterial strains including S. faecalis , MSSA and MRSA with the most potent antibacterial agent 8h (MICs = 0.06-0.12 mM). Besides, the 2-salicyloylbenzofurans partly displayed inhibitory activity against MRSA with the best MICs = 0.14 mM ( 8f ) and 0.12 mM ( 8h ). Finally, the antibacterial results preliminarily suggested that the substituent bearing carboxylic acid group at salicyloyl-C2 and the bromine atoms on the benzofuran moiety seem to be the functionality necessary for antibacterial activities.

18 GHz electromagnetic field induces permeability of Gram-positive cocci

PubMed Central

Nguyen, The Hong Phong; Shamis, Yury; Croft, Rodney J.; Wood, Andrew; McIntosh, Robert L.; Crawford, Russell J.; Ivanova, Elena P.

2015-01-01

The effect of electromagnetic field (EMF) exposures at the microwave (MW) frequency of 18 GHz, on four cocci, Planococcus maritimus KMM 3738, Staphylococcus aureus CIP 65.8T, S. aureus ATCC 25923 and S. epidermidis ATCC 14990T, was investigated. We demonstrate that exposing the bacteria to an EMF induced permeability in the bacterial membranes of all strains studied, as confirmed directly by transmission electron microscopy (TEM), and indirectly via the propidium iodide assay and the uptake of silica nanospheres. The cells remained permeable for at least nine minutes after EMF exposure. It was shown that all strains internalized 23.5 nm nanospheres, whereas the internalization of the 46.3 nm nanospheres differed amongst the bacterial strains (S. epidermidis ATCC 14990T~ 0%; Staphylococcus aureus CIP 65.8T S. aureus ATCC 25923, ~40%; Planococcus maritimus KMM 3738, ~80%). Cell viability experiments indicated that up to 84% of the cells exposed to the EMF remained viable. The morphology of the bacterial cells was not altered, as inferred from the scanning electron micrographs, however traces of leaked cytosolic fluids from the EMF exposed cells could be detected. EMF-induced permeabilization may represent an innovative, alternative cell permeability technique for applications in biomedical engineering, cell drug delivery and gene therapy. PMID:26077933

18 GHz electromagnetic field induces permeability of Gram-positive cocci.

PubMed

Nguyen, The Hong Phong; Shamis, Yury; Croft, Rodney J; Wood, Andrew; McIntosh, Robert L; Crawford, Russell J; Ivanova, Elena P

2015-06-16

The effect of electromagnetic field (EMF) exposures at the microwave (MW) frequency of 18 GHz, on four cocci, Planococcus maritimus KMM 3738, Staphylococcus aureus CIP 65.8(T), S. aureus ATCC 25923 and S. epidermidis ATCC 14990(T), was investigated. We demonstrate that exposing the bacteria to an EMF induced permeability in the bacterial membranes of all strains studied, as confirmed directly by transmission electron microscopy (TEM), and indirectly via the propidium iodide assay and the uptake of silica nanospheres. The cells remained permeable for at least nine minutes after EMF exposure. It was shown that all strains internalized 23.5 nm nanospheres, whereas the internalization of the 46.3 nm nanospheres differed amongst the bacterial strains (S. epidermidis ATCC 14990(T) ~  0%; Staphylococcus aureus CIP 65.8(T) S. aureus ATCC 25923, ~40%; Planococcus maritimus KMM 3738, ~ 80%). Cell viability experiments indicated that up to 84% of the cells exposed to the EMF remained viable. The morphology of the bacterial cells was not altered, as inferred from the scanning electron micrographs, however traces of leaked cytosolic fluids from the EMF exposed cells could be detected. EMF-induced permeabilization may represent an innovative, alternative cell permeability technique for applications in biomedical engineering, cell drug delivery and gene therapy.

Halomonas neptunia sp. nov., Halomonas sulfidaeris sp. nov., Halomonas axialensis sp. nov. and Halomonas hydrothermalis sp. nov.: halophilic bacteria isolated from deep-sea hydrothermal-vent environments.

PubMed

Kaye, Jonathan Z; Márquez, M Carmen; Ventosa, Antonio; Baross, John A

2004-03-01

To assess the physiological and phylogenetic diversity of culturable halophilic bacteria in deep-sea hydrothermal-vent environments, six isolates obtained from low-temperature hydrothermal fluids, sulfide rock and hydrothermal plumes in North and South Pacific Ocean vent fields located at 1530-2580 m depth were fully characterized. Three strains were isolated on media that contained oligotrophic concentrations of organic carbon (0.002 % yeast extract). Sequencing of the 16S rRNA gene indicated that all strains belonged to the genus Halomonas in the gamma-subclass of the Proteobacteria. Consistent with previously described species, the novel strains were slightly to moderately halophilic and grew in media containing up to 22-27 % total salts. The isolates grew at temperatures as low as -1 to 2 degrees C and had temperature optima of 30 or 20-35 degrees C. Both the minimum and optimum temperatures for growth were similar to those of Antarctic and sea-ice Halomonas species and lower than typically observed for the genus as a whole. Phenotypic tests revealed that the isolates were physiologically versatile and tended to have more traits in common with each other than with closely related Halomonas species, presumably a reflection of their common deep-sea, hydrothermal-vent habitat of origin. The G+C content of the DNA for all strains was 56.0-57.6 mol%, and DNA-DNA hybridization experiments revealed that four strains (Eplume1(T), Esulfide1(T), Althf1(T) and Slthf2(T)) represented novel species and that two strains (Eplume2 and Slthf1) were related to Halomonas meridiana. The proposed new species names are Halomonas neptunia (type strain Eplume1(T)=ATCC BAA-805(T)=CECT 5815(T)=DSM 15720(T)), Halomonas sulfidaeris (type strain Esulfide1(T)=ATCC BAA-803(T)=CECT 5817(T)=DSM 15722(T)), Halomonas axialensis (type strain Althf1(T)=ATCC BAA-802(T)=CECT 5812(T)=DSM 15723(T)) and Halomonas hydrothermalis (type strain Slthf2(T)=ATCC BAA-800(T)=CECT 5814(T)=DSM 15725(T)).

Enhancing fructooligosaccharides production by genetic improvement of the industrial fungus Aspergillus niger ATCC 20611.

PubMed

Zhang, Jing; Liu, Caixia; Xie, Yijia; Li, Ning; Ning, Zhanguo; Du, Na; Huang, Xirong; Zhong, Yaohua

2017-05-10

Aspergillus niger ATCC20611 is one of the most potent filamentous fungi used commercially for production of fructooligosaccharides (FOS), which are prospective components of functional food by stimulating probiotic bacteria in the human gut. However, current strategies for improving FOS yield still rely on production process development. The genetic engineering approach hasn't been applied in industrial strains to increase FOS production level. Here, an optimized polyethylene glycol (PEG)-mediated protoplast transformation system was established in A. niger ATCC 20611 and used for further strain improvement. The pyrithiamine resistance gene (ptrA) was selected as a dominant marker and protoplasts were prepared with high concentration (up to 10 8 g -1 wet weight mycelium) by using mixed cell wall-lysing enzymes. The transformation frequency with ptrA can reach 30-50 transformants per μg of DNA. In addition, the efficiency of co-transformation with the EGFP reporter gene (egfp) was high (approx. 82%). Furthermore, an activity-improved variant of β-fructofuranosidase, FopA(A178P), was successfully overexpressed in A. niger ATCC 20611 by using the transformation system. The transformant, CM6, exhibited a 58% increase in specific β-fructofuranosidase activity (up to 507U/g), compared to the parental strain (320U/g), and effectively reduced the time needed for completion of FOS synthesis. These results illustrate the feasibility of strain improvement through genetic engineering for further enhancement of FOS production level. Copyright © 2017 Elsevier B.V. All rights reserved.

Pharmacodynamics of moxifloxacin and levofloxacin against Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli: simulation of human plasma concentrations after intravenous dosage in an in vitro kinetic model.

PubMed

Odenholt, Inga; Cars, Otto

2006-11-01

To compare in an in vitro kinetic model the pharmacodynamics of moxifloxacin and levofloxacin with a concentration-time profile simulating the human free non-protein bound concentrations of 400 mg moxifloxacin intravenous (iv) once daily, 500 mg levofloxacin iv once daily and 750 mg levofloxacin iv once daily against strains of Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli with variable susceptibility to fluoroquinolones. The strains used in the study included S. pneumoniae ATCC 6306 (native strain), S. pneumoniae 19397 (double mutation; gyrA and parC), S. pneumoniae 4241 (single mutation; parC), S. aureus ATCC 13709 (native strain), S. aureus MB5 (single mutation; gyrA), E. coli M12 (single mutation; gyrA), E. coli ATCC 25922 (native strain) and K. pneumoniae ATCC 29655 (native strain). The strains were exposed to moxifloxacin and levofloxacin in an in vitro kinetic model simulating the free human serum concentration-time profile of moxifloxacin 400 mg once daily, levofloxacin 500 mg once daily and 750 mg once daily. Repeated samples were taken regularly during 24 h and viable counts were carried out. A correlation was seen between both the area under the serum concentration curve and MIC (AUC/MIC) and the peak concentration/MIC (Cmax/MIC) versus area under the bactericidal killing curve (AUBKC) or Deltalog0-24 cfu/mL. Compiling all data, an AUC/MIC of approximately 100 and a Cmax/MIC of 10 gave a maximal bactericidal effect for both levofloxacin and moxifloxacin. In accordance with the results from others, our study indicated that a lower AUC/MIC was needed for S. pneumoniae in comparison with the Gram-negative bacteria studied. Moxifloxacin yielded higher AUC/MIC and Cmax/MIC against the investigated Gram-positive bacteria in comparison with levofloxacin 500 mg once daily and 750 mg once daily.

Carbohydrate catabolic flexibility in the mammalian intestinal commensal Lactobacillus ruminis revealed by fermentation studies aligned to genome annotations

PubMed Central

2011-01-01

Background Lactobacillus ruminis is a poorly characterized member of the Lactobacillus salivarius clade that is part of the intestinal microbiota of pigs, humans and other mammals. Its variable abundance in human and animals may be linked to historical changes over time and geographical differences in dietary intake of complex carbohydrates. Results In this study, we investigated the ability of nine L. ruminis strains of human and bovine origin to utilize fifty carbohydrates including simple sugars, oligosaccharides, and prebiotic polysaccharides. The growth patterns were compared with metabolic pathways predicted by annotation of a high quality draft genome sequence of ATCC 25644 (human isolate) and the complete genome of ATCC 27782 (bovine isolate). All of the strains tested utilized prebiotics including fructooligosaccharides (FOS), soybean-oligosaccharides (SOS) and 1,3:1,4-β-D-gluco-oligosaccharides to varying degrees. Six strains isolated from humans utilized FOS-enriched inulin, as well as FOS. In contrast, three strains isolated from cows grew poorly in FOS-supplemented medium. In general, carbohydrate utilisation patterns were strain-dependent and also varied depending on the degree of polymerisation or complexity of structure. Six putative operons were identified in the genome of the human isolate ATCC 25644 for the transport and utilisation of the prebiotics FOS, galacto-oligosaccharides (GOS), SOS, and 1,3:1,4-β-D-Gluco-oligosaccharides. One of these comprised a novel FOS utilisation operon with predicted capacity to degrade chicory-derived FOS. However, only three of these operons were identified in the ATCC 27782 genome that might account for the utilisation of only SOS and 1,3:1,4-β-D-Gluco-oligosaccharides. Conclusions This study has provided definitive genome-based evidence to support the fermentation patterns of nine strains of Lactobacillus ruminis, and has linked it to gene distribution patterns in strains from different sources. Furthermore, the study has identified prebiotic carbohydrates with the potential to promote L. ruminis growth in vivo. PMID:21995520

Improved penicillin amidase production using a genetically engineered mutant of escherichia coli ATCC 11105

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robas, N.; Zouheiry, H.; Branlant, G.

Penicillin G amidase (PGA) is a key enzyme for the industrial production of penicillin G derivatives used in therapeutics. Escherichia coli ATCC 11105 is the more commonly used strain for PGA production. To improve enzyme yield, the authors constructed various recombinant E. coli HB 101 and ATCC 11105 strains. For each strain, PGA production was determined for various concentrations of glucose and phenylacetic acid (PAA) in the medium. The E. coli strain, G271, was identified as the best performer (800 U NIPAB/L). This strain was obtained as follows: an E. coli ATCC 11105 mutant (E. coli G133) was first selectedmore » based on a low negative effect of glucose on PGA production. This mutant was then transformed with a pBR322 derivative containing the PGA gene. Various experiments were made to try to understand the reason for the high productivity of E. coli G271. The host strain, E. coli G133, was found to be mutated in one (or more) gene(s) whose product(s) act(s) in trans on the PGA gene expression. Its growth is not inhibited by high glucose concentration in the medium. Interestingly, whereas glucose still exerts some negative effect on the PGA production by E. coli G133, PGA production by its transformant (E. coli G271) is stimulated by glucose. The reason for this stimulation is discussed. Transformation of E. coli G133 with a pBR322 derivative containing the HindIII fragment of the PGA gene, showed that the performance of E. coli G271 depends both upon the host strain properties and the plasmid structure. Study of the production by the less efficient E. coli HB101 derivatives brought some light on the mechanism of regulation of the PGA gene.« less

Reclassification of strains MAFF 303099T and R7A into Mesorhizobiumjaponicum sp. nov.

PubMed

Martínez-Hidalgo, Pilar; Ramírez-Bahena, Martha Helena; Flores-Félix, José David; Igual, José M; Sanjuán, Juan; León-Barrios, Milagros; Peix, Alvaro; Velázquez, Encarna

2016-12-01

In this work we revise the taxonomic status of the Lotus-nodulating strains MAFF 303099T and R7A isolated in Japan and New Zealand, respectively. Their 16S rRNA gene sequences are identical and show 98.0, 99.7, 99.8 and 99.9 % similarity values with respect to Mesorhizobium loti NZP 2213T, M. jarvisii ATCC 33669T, M. huakuii USDA 4779T (=CCBAU 2609T) and M. erdmanii USDA 3471T, respectively. The analysis of recA and glnII gene sequeces showed that M. jarvisii ATCC 33669T and M. huakuii USDA 4779T (=CCBAU 2609T) are the most closely related strains to MAFF 303099T and R7A, with similarity values suggesting that these two strains belong to a different species for which MAFF 303099T is selected as the type strain. The DNA-DNA relatedness values between strain MAFF 303099T and its closest phylogenetic relatives ranged from 53 to 60 % in average. Strains MAFF 303099T and R7A presented slight differences in the proportions of C18 : 1ω7c 11-methyl and C19 : 0 cyclo ω8c fatty acids with respect to M. jarvisii ATCC 33669T and M. huakuii USDA 4779T, and also in several phenotypic characteristics. Therefore, we propose the reclassification of these two strains into a novel species named Mesorhizobium japonicum sp. nov., with the type strain being MAFF 303099T (=LMG 29417T=CECT 9101T).

Assessment of the in vitro inhibitory activity of specific probiotic bacteria against different Escherichia coli strains.

PubMed

Mogna, Luca; Del Piano, Mario; Deidda, Francesca; Nicola, Stefania; Soattini, Liliana; Debiaggi, Rosaria; Sforza, Filomena; Strozzi, Gianpaolo; Mogna, Giovanni

2012-10-01

Lactobacilli and bifidobacteria are often associated with health-promoting effects. These live microorganisms, defined as probiotics, are commonly consumed as part of fermented foods, such as yoghurt and fermented milks, or as dietary supplements. Escherichia coli is a gram-negative, rod-shaped bacterium commonly found in the lower intestine of warm-blooded organisms. As a part of the normal gut microbiota, this microorganism colonizes the gastrointestinal tract of animals and humans within a few hours after birth. All E. coli strains can produce a wide variety of biogenic amines responsible for potentially harmful systemic intoxications. Enterohemorrhagic E. coli serotype O157:H7 is a pathotype of diarrhoeagenic strains with a large virulence plasmid pO157 able to produce 1 or more Shiga toxins. The overall aim of this study was to determine the inhibitory effects of different strains of probiotics on E. coli serotypes, including E. coli O157:H7 (CQ9485). In particular, the antagonistic activity of 4 Bifidobacterium strains (Probiotical SpA, Italy) and 16 lactic acid bacteria, more specifically 14 Lactobacillus spp. and 2 Streptococcus spp., was assessed against selected E. coli biotypes (ATCC 8739, ATCC 10536, ATCC 35218, and ATCC 25922). The diarrhoeagenic serotype O157:H7 was also tested. The experimental data collected demonstrated an in vitro significant inhibitory effect of 6 Lactobacillus strains, namely L. rhamnosus LR04, L. rhamnosus LR06, L. plantarum LP01, L. plantarum LP02, L. pentosus LPS01, and L. delbrueckii subsp. delbrueckii LDD01, and 2 Bifidobacterium strains, B. breve BR03 and B. breve B632. The inhibiting extent was slightly different among these strains, with L. delbrueckii subsp. delbrueckii LDD01 showing the highest activity on E. coli O157:H7. Most of the probiotics studied are able to antagonize the growth of the 5 strains of E. coli tested, including the O157:H7 biotype, well known for their characteristic to produce a wide variety of biogenic amines considered responsible for dangerous systemic intoxications.

Candida albicans and Pseudomonas aeruginosa adhesion on soft contact lenses.

PubMed

Onurdağ, Fatma Kaynak; Ozkan, Semiha; Ozgen, Selda; Olmuş, Hülya; Abbasoğlu, Ufuk

2011-04-01

In this study it was aimed to determine the adherence of Pseudomonas and Candida to contact lens surfaces, and to determine the difference in adherence between five contact lens types. Biofilm-negative control strains were also used to emphasize the difference between biofilm-positive and biofilm-negative strains in adherence. Five different soft contact lenses were used to investigate the adherence of Pseudomonas aeruginosa and Candida albicans strains. P. aeruginosa ATCC 27853, P. aeruginosa ATCC 10145, C.albicans ATCC 10231 standard strains and C. albicans clinical isolate were included in the study. Slime formation was investigated by two methods; modified Christensen macrotube method, and a modified microtiter plate test. P. aeruginosa and C. albicans slime formation on soft contact lenses was studied in adherence and separation phases. Pseudomonas and Candida suspensions were serially diluted and inoculated to blood agar and sabouraud dextrose agar surfaces respectively. After overnight incubation, the colonies were counted. Sterile unworn contact lenses were used as negative controls, and bacterial and fungal culture suspensions were used as positive controls. The experiments were conducted in three parallel series. The number of adherent Pseudomonas was as follows from high to low in polymacon, etafilcon A, hilafilcon, ocufilcon and lotrafilcon contact lenses respectively. However, the number of adherent yeast were determined higher in lotrafilcon and ocufilcon contact lenses, followed by hilafilcon, etafilcon A and polymacon contact lenses. Biofilm-negative Pseudomonas ATCC standard strain and Candida clinical isolate were used to confirm that the number of adherent cells were lower than the biofilm-positive ones. This study demonstrates that in addition to the contact lens properties, the microorganisms themselves and their interactions with the lens material also play an important role in adherence.

Mutual Cross-Feeding Interactions between Bifidobacterium longum subsp. longum NCC2705 and Eubacterium rectale ATCC 33656 Explain the Bifidogenic and Butyrogenic Effects of Arabinoxylan Oligosaccharides

PubMed Central

Rivière, Audrey; Gagnon, Mérilie; Weckx, Stefan; Roy, Denis

2015-01-01

Arabinoxylan oligosaccharides (AXOS) are a promising class of prebiotics that have the potential to stimulate the growth of bifidobacteria and the production of butyrate in the human colon, known as the bifidogenic and butyrogenic effects, respectively. Although these dual effects of AXOS are considered beneficial for human health, their underlying mechanisms are still far from being understood. Therefore, this study investigated the metabolic interactions between Bifidobacterium longum subsp. longum NCC2705 (B. longum NCC2705), an acetate producer and arabinose substituent degrader of AXOS, and Eubacterium rectale ATCC 33656, an acetate-converting butyrate producer. Both strains belong to prevalent species of the human colon microbiota. The strains were grown on AXOS during mono- and coculture fermentations, and their growth, AXOS consumption, metabolite production, and expression of key genes were monitored. The results showed that the growth of both strains and gene expression in both strains were affected by cocultivation and that these effects could be linked to changes in carbohydrate consumption and concomitant metabolite production. The consumption of the arabinose substituents of AXOS by B. longum NCC2705 with the concomitant production of acetate allowed E. rectale ATCC 33656 to produce butyrate (by means of a butyryl coenzyme A [CoA]:acetate CoA-transferase), explaining the butyrogenic effect of AXOS. Eubacterium rectale ATCC 33656 released xylose from the AXOS substrate, which favored the B. longum NCC2705 production of acetate, explaining the bifidogenic effect of AXOS. Hence, those interactions represent mutual cross-feeding mechanisms that favor the coexistence of bifidobacterial strains and butyrate producers in the same ecological niche. In conclusion, this study provides new insights into the bifidogenic and butyrogenic effects of AXOS. PMID:26319874

Biotransformation of ferulic acid to protocatechuic acid by Corynebacterium glutamicum ATCC 21420 engineered to express vanillate O-demethylase.

PubMed

Okai, Naoko; Masuda, Takaya; Takeshima, Yasunobu; Tanaka, Kosei; Yoshida, Ken-Ichi; Miyamoto, Masanori; Ogino, Chiaki; Kondo, Akihiko

2017-12-01

Ferulic acid (4-hydroxy-3-methoxycinnamic acid, FA) is a lignin-derived phenolic compound abundant in plant biomass. The utilization of FA and its conversion to valuable compounds is desired. Protocatechuic acid (3,4-dihydroxybenzoic acid, PCA) is a precursor of polymers and plastics and a constituent of food. A microbial conversion system to produce PCA from FA was developed in this study using a PCA-producing strain of Corynebacterium glutamicum F (ATCC 21420). C. glutamicum strain F grown at 30 °C for 48 h utilized 2 mM each of FA and vanillic acid (4-hydroxy-3-methoxybenzoic acid, VA) to produce PCA, which was secreted into the medium. FA may be catabolized by C. glutamicum through proposed (I) non-β-oxidative, CoA-dependent or (II) β-oxidative, CoA-dependent phenylpropanoid pathways. The conversion of VA to PCA is the last step in each pathway. Therefore, the vanillate O-demethylase gene (vanAB) from Corynebacterium efficiens NBRC 100395 was expressed in C. glutamicum F (designated strain FVan) cultured at 30 °C in AF medium containing FA. Strain C. glutamicum FVan converted 4.57 ± 0.07 mM of FA into 2.87 ± 0.01 mM PCA after 48 h with yields of 62.8% (mol/mol), and 6.91 mM (1064 mg/L) of PCA was produced from 16.0 mM of FA after 12 h of fed-batch biotransformation. Genomic analysis of C. glutamicum ATCC 21420 revealed that the PCA-utilization genes (pca cluster) were conserved in strain ATCC 21420 and that mutations were present in the PCA importer gene pcaK.

Diverse Responses to UV-B Radiation and Repair Mechanisms of Bacteria Isolated from High-Altitude Aquatic Environments▿

PubMed Central

Fernández Zenoff, V.; Siñeriz, F.; Farías, M. E.

2006-01-01

Acinetobacter johnsonii A2 isolated from the natural community of Laguna Azul (Andean Mountains at 4,560 m above sea level), Serratia marcescens MF42, Pseudomonas sp. strain MF8 isolated from the planktonic community, and Cytophaga sp. strain MF7 isolated from the benthic community from Laguna Pozuelos (Andean Puna at 3,600 m above sea level) were subjected to UV-B (3,931 J m−2) irradiation. In addition, a marine Pseudomonas putida strain, 2IDINH, and a second Acinetobacter johnsonii strain, ATCC 17909, were used as external controls. Resistance to UV-B and kinetic rates of light-dependent (UV-A [315 to 400 nm] and cool white light [400 to 700 nm]) and -independent reactivation following exposure were determined by measuring the survival (expressed as CFU) and accumulation of cyclobutane pyrimidine dimers (CPD). Significant differences in survival after UV-B irradiation were observed: Acinetobacter johnsonii A2, 48%; Acinetobacter johnsonii ATCC 17909, 20%; Pseudomonas sp. strain MF8, 40%; marine Pseudomonas putida strain 2IDINH, 12%; Cytophaga sp. strain MF7, 20%; and Serratia marcescens, 21%. Most bacteria exhibited little DNA damage (between 40 and 80 CPD/Mb), except for the benthic isolate Cytophaga sp. strain MF7 (400 CPD/Mb) and Acinetobacter johnsonii ATCC 17909 (160 CPD/Mb). The recovery strategies through dark and light repair were different in all strains. The most efficient in recovering were both Acinetobacter johnsonii A2 and Cytophaga sp. strain MF7; Serratia marcescens MF42 showed intermediate recovery, and in both Pseudomonas strains, recovery was essentially zero. The UV-B responses and recovery abilities of the different bacteria were consistent with the irradiation levels in their native environment. PMID:17056692

The coxBAC Operon Encodes a Cytochrome c Oxidase Required for Heterotrophic Growth in the Cyanobacterium Anabaena variabilis Strain ATCC 29413

PubMed Central

Schmetterer, Georg; Valladares, Ana; Pils, Dietmar; Steinbach, Susanne; Pacher, Margit; Muro-Pastor, Alicia M.; Flores, Enrique; Herrero, Antonia

2001-01-01

Three genes, coxB, coxA, and coxC, found in a clone from a gene library of the cyanobacterium Anabaena variabilis strain ATCC 29413, were identified by hybridization with an oligonucleotide specific for aa3-type cytochrome c oxidases. Deletion of these genes from the genome of A. variabilis strain ATCC 29413 FD yielded strain CSW1, which displayed no chemoheterotrophic growth and an impaired cytochrome c oxidase activity. Photoautotrophic growth of CSW1, however, was unchanged, even with dinitrogen as the nitrogen source. A higher cytochrome c oxidase activity was detected in membrane preparations from dinitrogen-grown CSW1 than from nitrate-grown CSW1, but comparable activities of respiratory oxygen uptake were found in the wild type and in CSW1. Our data indicate that the identified cox gene cluster is essential for fructose-dependent growth in the dark, but not for growth on dinitrogen, and that other terminal respiratory oxidases are expressed in this cyanobacterium. Transcription analysis showed that coxBAC constitutes an operon which is expressed from two transcriptional start points. The use of one of them was stimulated by fructose. PMID:11591688

[Cloning of Enterobacter aerogenes fh1A gene and overexpression of hydrogen production].

PubMed

Zhao, Jinfang; Song, Wenlu; Cheng, Jun; Zhang, Chuanxi

2010-06-01

We amplified and overexpressed the FHL activator (fh1A) in E. aerogenes ATCC13408 to enhance hydrogen production. By using universal primers and genome walking, we cloned the full open reading frame (ORF) of fh1A gene. We inserted it into the glutathion S-transferase (GST) fusion expression vector pGEX4T-2-Cat, and transformed the recombinant plasmid into E. aerogenes ATCC13408 via electroporation for expression. Then we measured the hydrogen production of the recombinant strain in a batch culture. We found that the ORF of fh1A was 2073 base pair in length, potential to encode a 690 amino acid peptide (GenBank accession GU188474). The Fh1A protein from E. aerogenes ATCC13408 shared high amino acid identities with those from other bacterial species. By using SDS-PAGE and Western blot analysis, we confirmed that the fh1A gene had successfully expressed in the strain. The hydrogen yield of the recombinant strain was increased from 1.23 to 1.48 mol H2/mol glucose. [ Conclusion ] Enhancement of hydrogen productivity was attained under anaerobic conditions with the recombinant strain.

Antimicrobial Activity of Medicated Soaps Commonly Used By Dar es Salaam Residents in Tanzania.

PubMed

Mwambete, K D; Lyombe, F

2011-01-01

An in vitro evaluation of the anti-microbial activity of medicated soaps was conducted using ditch-plate and hand washing techniques. Strains of reference microbes namely Candida albicans (ATCC90028), Staphylococcus aureus (ATCC25923), Pseudomonas aureginosa (ATCC27853) and Escherichia coli (ATCC25922) were tested at three different soaps' concentrations (1.0, 4.0 and 8.0 mg/ml). A total of 16 medicated soaps were assayed for their antimicrobial efficacy. Of these, 13 were medicated and 3 non-medicated soaps, which served as control. Ciprofloxacin and ketaconazole were employed as positive controls. Label disclosure for the soaps' ingredients and other relevant information were absorbed. The most common antimicrobial active ingredients were triclosan, trichloroxylenol and trichlorocarbanilide. ANOVA for means of zones of inhibition revealed variability of antimicrobial activity among the medicated soaps. Positive correlation (r=0.318; P<0.01) between zones of inhibition and soaps' concentrations was evidenced. Hand washing frequencies positively correlated with microbial counts. Roberts(®) soap exhibited the largest zone of inhibition (34 mm) on S. aureus. Candida albicans was the least susceptible microbe. Regency(®) and Dalan(®) exhibited the least zone of inhibition on the tested bacteria. Protex(®), Roberts(®), Family(®) and Protector(®) were equally effective (P<0.01) against S. aureus. In conclusion, majority of the assayed medicated soaps have satisfactory antibacterial activity; though lack antifungal effect with exception of Linda(®) liquid soap. The hand washing technique has proved to be inappropriate for evaluation of soaps' antimicrobial efficacy due to presence of the skin microflora.

Antimicrobial Activity of Medicated Soaps Commonly Used By Dar es Salaam Residents in Tanzania

PubMed Central

Mwambete, K. D.; Lyombe, F.

2011-01-01

An in vitro evaluation of the anti-microbial activity of medicated soaps was conducted using ditch-plate and hand washing techniques. Strains of reference microbes namely Candida albicans (ATCC90028), Staphylococcus aureus (ATCC25923), Pseudomonas aureginosa (ATCC27853) and Escherichia coli (ATCC25922) were tested at three different soaps’ concentrations (1.0, 4.0 and 8.0 mg/ml). A total of 16 medicated soaps were assayed for their antimicrobial efficacy. Of these, 13 were medicated and 3 non-medicated soaps, which served as control. Ciprofloxacin and ketaconazole were employed as positive controls. Label disclosure for the soaps’ ingredients and other relevant information were absorbed. The most common antimicrobial active ingredients were triclosan, trichloroxylenol and trichlorocarbanilide. ANOVA for means of zones of inhibition revealed variability of antimicrobial activity among the medicated soaps. Positive correlation (r=0.318; P<0.01) between zones of inhibition and soaps’ concentrations was evidenced. Hand washing frequencies positively correlated with microbial counts. Roberts® soap exhibited the largest zone of inhibition (34 mm) on S. aureus. Candida albicans was the least susceptible microbe. Regency® and Dalan® exhibited the least zone of inhibition on the tested bacteria. Protex®, Roberts®, Family® and Protector® were equally effective (P<0.01) against S. aureus. In conclusion, majority of the assayed medicated soaps have satisfactory antibacterial activity; though lack antifungal effect with exception of Linda® liquid soap. The hand washing technique has proved to be inappropriate for evaluation of soaps’ antimicrobial efficacy due to presence of the skin microflora. PMID:22131630

Plant growth promoting rhizobacterium

DOEpatents

Doktycz, Mitchel John; Pelletier, Dale A.; Schadt, Christopher Warren; Tuskan, Gerald A.; Weston, David

2015-08-11

The present invention is directed to the Pseudomonas fluorescens strain GM30 deposited under ATCC Accession No. PTA-13340, compositions containing the GM30 strain, and methods of using the GM30 strain to enhance plant growth and/or enhance plant resistance to pathogens.

Escherichia marmotae sp. nov., isolated from faeces of Marmota himalayana.

PubMed

Liu, Sha; Jin, Dong; Lan, Ruiting; Wang, Yiting; Meng, Qiong; Dai, Hang; Lu, Shan; Hu, Shoukui; Xu, Jianguo

2015-07-01

The taxonomic position of a group of seven closely related lactose-negative enterobacterial strains, which were isolated from fresh faecal samples of Marmota himalayana collected from the Qinghai-Tibetan plateau, China, was determined by using a polyphasic approach. Cells were Gram-reaction-negative, non-sporulating, non-motile, short rods (0.5-1 × 1-2.5 μm). By 16S rRNA gene sequences, the representative strain, HT073016(T), showed highest similarity values with Escherichia fergusonii ATCC 35469(T) at 99.3%, Escherichia coli ATCC 11775(T) at 99.2%, Escherichia albertii LMG 20976(T) at 98.9%, Escherichia hermannii CIP 103176(T) at 98.4%, and Escherichia vulneris ATCC 33821(T) at 97.7%. Phylogenetic analysis based on the 16S rRNA gene sequences showed that the seven strains formed a monophyletic group with five other species of the genus Escherichia. Digital DNA-DNA hybridization studies between strain HT073016(T) and five other species of the genus Escherichia showed that it shared less than 70% DNA-DNA relatedness with all known species of the genus Escherichia, supporting the novel species status of the strain. The DNA G+C content of strain HT073016(T) was 53.8 mol%. On the basis of phenotypic and phylogenetic characteristics, strain HT073016(T) and the six other HT073016(T)-like strains were clearly distinct from the type strains of other recognized species of the genus Escherichia and represent a novel species of the genus Escherichia, for which the name Escherichia marmotae sp. nov. is proposed, with HT073016(T) ( = CGMCC 1.12862(T) = DSM 28771(T)) as the type strain.

Characterization of CIA-1, an Ambler class A extended-spectrum β-lactamase from Chryseobacterium indologenes.

PubMed

Matsumoto, Takehisa; Nagata, Mika; Ishimine, Nau; Kawasaki, Kenji; Yamauchi, Kazuyoshi; Hidaka, Eiko; Kasuga, Eriko; Horiuchi, Kazuki; Oana, Kozue; Kawakami, Yoshiyuki; Honda, Takayuki

2012-01-01

An Ambler class A β-lactamase gene, bla(CIA-1), was cloned from the reference strain Chryseobacterium indologenes ATCC 29897 and expressed in Escherichia coli BL21. The bla(CIA-1) gene encodes a novel extended-spectrum β-lactamase (ESBL) that shared 68% and 60% identities with the CGA-1 and CME-1 β-lactamases, respectively. bla(CIA-1)-like genes were detected from clinical isolates. In addition to the metallo-β-lactamase IND of Ambler class B, C. indologenes has a class A ESBL gene, bla(CIA-1), located on the chromosome.

Prophylactic Bifidobacterium adolescentis ATTCC 15703 supplementation reduces partially allergic airway disease in Balb/c but not in C57BL/6 mice.

PubMed

Casaro, M C; Crisma, A R; Vieira, A T; Silva, G H M; Mendes, E; Ribeiro, W R; Martins, F S; Ferreira, C M

2018-04-25

Allergic asthma is a chronic disease mainly characterised by eosinophil inflammation and airway remodelling. Many studies have shown that the gut microbiota of allergic individuals differs from that of non-allergic individuals. Although high levels of bifidobacteria have been associated with healthy persons, Bifidobacterium adolescentis ATCC 15703, a gut bacteria, has been associated with allergic individuals in some clinical studies. The relationship between B. adolescentis ATCC 15703 and asthma or allergies has not been well elucidated, and its effect may be dependent on the host's genetic profile or disease state. To elucidate this question, we evaluated the role of preventive B. adolescentis ATCC 15703 treatment on experimental allergic airway inflammation in two genetically different mouse strains, Balb/c and C57BL/6 (B6). Balb/c mice display a greater predisposition to develop allergic responses than B6 mice. Oral preventive treatment with B. adolescentis ATCC 15703 modulated experimental allergic airway inflammation, specifically in Balb/c mice, which showed decreased levels of eosinophils in the airway. B6 mice did not exhibit any significant alterations in eosinophils but showed an increased influx of total leukocytes and neutrophils into the airway. The mechanism underlying the beneficial effects of these bacteria in experimental allergic mice may involve products of bacteria metabolism, as dead bacteria did not mimic the ability of live B. adolescentis ATCC 15703 to attenuate the influx of eosinophils into the airway. To conclude, preventive oral B. adolescentis ATCC 15703 treatment can attenuate the major characteristic of allergic asthma, eosinophil airway influx, in Balb/c but not B6 mice. These results suggest that oral treatment with this specific live bacterial strain may have therapeutic potential for the treatment of allergic airway disease, although its effect is mouse-strain-dependent.

A comprehensive multi-omics approach uncovers adaptations for growth and survival of Pseudomonas aeruginosa on n-alkanes.

PubMed

Grady, Sarah L; Malfatti, Stephanie A; Gunasekera, Thusitha S; Dalley, Brian K; Lyman, Matt G; Striebich, Richard C; Mayhew, Michael B; Zhou, Carol L; Ruiz, Oscar N; Dugan, Larry C

2017-04-28

Examination of complex biological systems has long been achieved through methodical investigation of the system's individual components. While informative, this strategy often leads to inappropriate conclusions about the system as a whole. With the advent of high-throughput "omic" technologies, however, researchers can now simultaneously analyze an entire system at the level of molecule (DNA, RNA, protein, metabolite) and process (transcription, translation, enzyme catalysis). This strategy reduces the likelihood of improper conclusions, provides a framework for elucidation of genotype-phenotype relationships, and brings finer resolution to comparative genomic experiments. Here, we apply a multi-omic approach to analyze the gene expression profiles of two closely related Pseudomonas aeruginosa strains grown in n-alkanes or glycerol. The environmental P. aeruginosa isolate ATCC 33988 consumed medium-length (C 10 -C 16 ) n-alkanes more rapidly than the laboratory strain PAO1, despite high genome sequence identity (average nucleotide identity >99%). Our data shows that ATCC 33988 induces a characteristic set of genes at the transcriptional, translational and post-translational levels during growth on alkanes, many of which differ from those expressed by PAO1. Of particular interest was the lack of expression from the rhl operon of the quorum sensing (QS) system, resulting in no measurable rhamnolipid production by ATCC 33988. Further examination showed that ATCC 33988 lacked the entire lasI/lasR arm of the QS response. Instead of promoting expression of QS genes, ATCC 33988 up-regulates a small subset of its genome, including operons responsible for specific alkaline proteases and sphingosine metabolism. This work represents the first time results from RNA-seq, microarray, ribosome footprinting, proteomics, and small molecule LC-MS experiments have been integrated to compare gene expression in bacteria. Together, these data provide insights as to why strain ATCC 33988 is better adapted for growth and survival on n-alkanes.

A comprehensive multi-omics approach uncovers adaptations for growth and survival of Pseudomonas aeruginosa on n-alkanes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grady, Sarah L.; Malfatti, Stephanie A.; Gunasekera, Thusitha S.

Examination of complex biological systems has long been achieved through methodical investigation of the system’s individual components. While informative, this strategy often leads to inappropriate conclusions about the system as a whole. With the advent of high-throughput “omic” technologies, but, researchers can now simultaneously analyze an entire system at the level of molecule (DNA, RNA, protein, metabolite) and process (transcription, translation, enzyme catalysis). This strategy reduces the likelihood of improper conclusions, provides a framework for elucidation of genotype-phenotype relationships, and brings finer resolution to comparative genomic experiments. Here in this paper, we apply a multi-omic approach to analyze the genemore » expression profiles of two closely related Pseudomonas aeruginosa strains grown in n-alkanes or glycerol. The environmental P. aeruginosa isolate ATCC 33988 consumed medium-length (C 10–C 16) n-alkanes more rapidly than the laboratory strain PAO1, despite high genome sequence identity (average nucleotide identity >99%). Our data shows that ATCC 33988 induces a characteristic set of genes at the transcriptional, translational and post-translational levels during growth on alkanes, many of which differ from those expressed by PAO1. Of particular interest was the lack of expression from the rhl operon of the quorum sensing (QS) system, resulting in no measurable rhamnolipid production by ATCC 33988. Further examination showed that ATCC 33988 lacked the entire lasI/lasR arm of the QS response. Instead of promoting expression of QS genes, ATCC 33988 up-regulates a small subset of its genome, including operons responsible for specific alkaline proteases and sphingosine metabolism. Our work represents the first time results from RNA-seq, microarray, ribosome footprinting, proteomics, and small molecule LC-MS experiments have been integrated to compare gene expression in bacteria. Altogether, these data provide insights as to why strain ATCC 33988 is better adapted for growth and survival on n-alkanes.« less

A comprehensive multi-omics approach uncovers adaptations for growth and survival of Pseudomonas aeruginosa on n-alkanes

DOE PAGES

Grady, Sarah L.; Malfatti, Stephanie A.; Gunasekera, Thusitha S.; ...

2017-04-28

Examination of complex biological systems has long been achieved through methodical investigation of the system’s individual components. While informative, this strategy often leads to inappropriate conclusions about the system as a whole. With the advent of high-throughput “omic” technologies, but, researchers can now simultaneously analyze an entire system at the level of molecule (DNA, RNA, protein, metabolite) and process (transcription, translation, enzyme catalysis). This strategy reduces the likelihood of improper conclusions, provides a framework for elucidation of genotype-phenotype relationships, and brings finer resolution to comparative genomic experiments. Here in this paper, we apply a multi-omic approach to analyze the genemore » expression profiles of two closely related Pseudomonas aeruginosa strains grown in n-alkanes or glycerol. The environmental P. aeruginosa isolate ATCC 33988 consumed medium-length (C 10–C 16) n-alkanes more rapidly than the laboratory strain PAO1, despite high genome sequence identity (average nucleotide identity >99%). Our data shows that ATCC 33988 induces a characteristic set of genes at the transcriptional, translational and post-translational levels during growth on alkanes, many of which differ from those expressed by PAO1. Of particular interest was the lack of expression from the rhl operon of the quorum sensing (QS) system, resulting in no measurable rhamnolipid production by ATCC 33988. Further examination showed that ATCC 33988 lacked the entire lasI/lasR arm of the QS response. Instead of promoting expression of QS genes, ATCC 33988 up-regulates a small subset of its genome, including operons responsible for specific alkaline proteases and sphingosine metabolism. Our work represents the first time results from RNA-seq, microarray, ribosome footprinting, proteomics, and small molecule LC-MS experiments have been integrated to compare gene expression in bacteria. Altogether, these data provide insights as to why strain ATCC 33988 is better adapted for growth and survival on n-alkanes.« less

Screening of Probiotic Activities of Lactobacilli Strains Isolated from Traditional Tibetan Qula, A Raw Yak Milk Cheese

PubMed Central

Zhang, Bei; Wang, Yanping; Tan, Zhongfang; Li, Zongwei; Jiao, Zhen; Huang, Qunce

2016-01-01

In this study, 69 lactobacilli isolated from Tibetan Qula, a raw yak milk cheese, were screened for their potential use as probiotics. The isolates were tested in terms of: Their ability to survive at pH 2.0, pH 3.0, and in the presence of 0.3% bile salts; tolerance of simulated gastric and intestinal juices; antimicrobial activity; sensitivity against 11 specific antibiotics; and their cell surface hydrophobicity. The results show that out of the 69 strains, 29 strains (42%) had survival rates above 90% after 2 h of incubation at pH values of 2.0 or 3.0. Of these 29 strains, 21 strains showed a tolerance for 0.3% bile salt. Incubation of these 21 isolates in simulated gastrointestinal fluid for 3 h revealed survival rates above 90%; the survival rate for 20 of these isolates remained above 90% after 4 h of incubation in simulated intestinal fluid. The viable counts of bacteria after incubation in simulated gastric fluid for 3 h and simulated intestinal fluid for 4 h were both significantly different compared with the counts at 0 h (p<0.001). Further screening performed on the above 20 isolates indicated that all 20 lactobacilli strains exhibited inhibitory activity against Micrococcus luteus ATCC 4698, Bacillus subtilis ATCC 6633, Listeria monocytogenes ATCC 19115, and Salmonella enterica ATCC 43971. Moreover, all of the strains were resistant to vancomycin and streptomycin. Of the 20 strains, three were resistant to all 11 elected antibiotics (ciprofloxacin, erythromycin, tetracycline, penicillin G, ampicillin, streptomycin, polymyxin B, vancomycin, chloramphenicol, rifampicin, and gentamicin) in this study, and five were sensitive to more than half of the antibiotics. Additionally, the cell surface hydrophobicity of seven of the 20 lactobacilli strains was above 70%, including strains Lactobacillus casei 1,133 (92%), Lactobacillus plantarum 1086-1 (82%), Lactobacillus casei 1089 (81%), Lactobacillus casei 1138 (79%), Lactobacillus buchneri 1059 (78%), Lactobacillus plantarum1141 (75%), and Lactobacillus plantarum 1197 (71%). Together, these results suggest that these seven strains are good probiotic candidates, and that tolerance against bile acid, simulated gastric and intestinal juices, antimicrobial activity, antibiotic resistance, and cell surface hydrophobicity could be adopted for preliminary screening of potentially probiotic lactobacilli. PMID:26954218

Antimicrobial activity and chemical composition of the essential oils of Portuguese Foeniculum vulgare fruits.

PubMed

Mota, Ana S; Martins, M Rosário; Arantes, Sílvia; Lopes, Violeta R; Bettencourt, Eliseu; Pombal, Sofia; Gomes, Arlindo C; Silva, Lúcia A

2015-04-01

The aim of this study was to investigate the chemical composition and antimicrobial activity of essential oils obtained by hydrodistillation from fruits of six fennel accessions collected from wild populations occurring in the centre and south of Portugal. Composition of essential oils was established by Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The obtained yields of the essential oils were found to vary greatly in the range of 1.1 to 2.9% (v/w) and the chemical composition varied with the region of collection. A total of 16 compounds were identified. The main compounds were fenchone (16.9 - 34.7%), estragole (2.5 - 66.0%) and trans-anethole (7.9 - 77.7%). The percentages of these three main compounds were used to determine the relationship between the different oil samples and to group them into four different chemotypes: anethole/fenchone; anethole; estragole and anethole/estragole. Antifungal activity of essential oils was evaluated against six food spoilage fungi: Aspergillus niger, A. japonicus, A. oryzae, Fusarium oxysporum, Rhizophus oryzae and R. stolonifer. Antibacterial activity was assessed against three Gram-positive strains: Enterococcus faecalis ATCC 29212, Staphylococcus epidermidis ATCC 12228 and S. aureus ATCC 28213; and against six Gram-negative strains: Escherichia coli ATCC 25922; Morganella morganii LFG 08; Proteus mirabilis LFG 04; Salmonella enteritidis LFG 05; S. entiritidis serovar typhimurium LFG 06 and Pseudomonas aeruginosa ATCC 27853 by the disc diffusion agar method; the minimal inhibitory concentration (MIC) was determined using the broth macro-dilution method. The MIC values varied from 62.5 (E. coli ATCC 25922) to 2000 µmL (P. aeruginosa ATCC 27853).

Fermentation of sarshir (kaymak) by lactic acid bacteria: antibacterial activity, antioxidant properties, lipid and protein oxidation and fatty acid profile.

PubMed

Hashemi, Seyed Mohammad Bagher; Mousavi Khaneghah, Amin; Kontominas, Michael G; Eş, Ismail; Sant'Ana, Anderson S; Martinez, Rafael R; Drider, Djamel

2017-10-01

The antioxidant and antibacterial activities of fermented sarshir (traditional dairy food), with three probiotic Lactobacillus plantarum strains (LP3, AF1, and LU5), were investigated. The oxidative stability and the lipid profile of non-fermented and fermented sarshir were compared, in addition to radical scavenging activity, as well as peroxide, anisidine and carbonyl values (PV, AnV and CV, respectively). The strong antibacterial activity of fermented sarshir against common pathogenic bacteria, including Gram-negative Escherichia coli O157: H7 ATCC 35150 and Pseudomonas aeruginosa ATCC 27853, as well as Gram-positive Bacillus cereus ATCC 10876 and Staphylococcus aureus ATCC 25923, was established. Among the strains examined, L. plantarum LP3 exhibited the highest radical scavenging activity (53.1 ± 1.8%) and lowest PV (3.0 meq kg -1 ), AnV (1.31 ± 0.06) and CV (1.4 ± 0.08). The pH of sarshir decreased from 6.2 ± 0 to 3.5 ± 0.1 during 14 h of fermentation. Incorporated bacterial cells exhibited notable viability during 10 days of cold storage (4 °C). The fermentation of sarshir by L. plantarum strains, especially LP3, resulted in beneficial changes in radical scavenging activity, as well as PV, AnV and carbonyl values, in addition to a broad spectrum of inhibitory activity against strains of P. aeruginosa, E. coli O157:H7, B. cereus and S. aureus. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Antibacterial Activity of Copaiba Oil Gel on Dental Biofilm

PubMed Central

Simões, Cláudia A.C.G.; Conde, Nikeila C. de Oliveira; Venâncio, Gisely N.; Milério, Patrícia S.L.L.; Bandeira, Maria F.C.L.; da Veiga Júnior, Valdir F.

2016-01-01

Amazonian biodiversity products that have been used for years in folk medicine, have emerged as feasible and promising alternatives for the inhibition of microorganisms in dental biofilm. Copaiba oil, a phytotherapic agent widely used by the Amazonian populations, is known for its antibacterial, anti-inflammatory, anesthetic, healing and antitumor medicinal properties. Objective: The aim of this study was to evaluate the in vitro antibacterial activity of copaiba oil (Copaifera multijuga) gel against strains of Streptococcus sp present in dental biofilm. Materials and Methods: The copaiba oil was obtained and the chemical components were identified. The oil emulsions were formulated and used with the Brain Heart Infusion agar diffusion method with strains of Streptococcus mitis, Streptococcus constellatus and Streptococcus salivarius isolated from patients as well as standard strains of S. mitis (ATCC903), S. mutans (ATCC10449), S. sanguinis (ATCC15300) and S. oralis (ATCC10557). The study groups were as follows: experimental copaiba oil gel, 1% chlorhexidine gel (positive control) and base gel (negative control). The seeded plates were incubated at 37ºC for 12, 24 and 48 hours, respectively. The results obtained were analyzed by Shapiro-Wilk and Friedman Tests (p<0.05) for non parametric data and the Tukey test was used for pH values with 5% level of significance. Results: The experimental copaiba oil gel and 1% chlorhexidine gel showed antibacterial activity against the tested microorganisms. Conclusion: The copaiba oil gel demonstrated antibacterial activity against all the strains of Streptococcus sp tested, suggesting that it can be used for dental biofilm control. PMID:27386004

Genetic variability in isolates of Chromobacterium violaceum from pulmonary secretion, water, and soil.

PubMed

Santini, A C; Magalhães, J T; Cascardo, J C M; Corrêa, R X

2016-04-28

Chromobacterium violaceum is a free-living Gram-negative bacillus usually found in the water and soil in tropical regions, which causes infections in humans. Chromobacteriosis is characterized by rapid dissemination and high mortality. The aim of this study was to detect the genetic variability among C. violaceum type strain ATCC 12472, and seven isolates from the environment and one from a pulmonary secretion from a chromobacteriosis patient from Ilhéus, Bahia. The molecular characterization of all samples was performed by polymerase chain reaction (PCR) sequencing and 16S rDNA analysis. Primers specific for two ATCC 12472 pathogenicity genes, hilA and yscD, as well as random amplified polymorphic DNA (RAPD), were used for PCR amplification and comparative sequencing of the products. For a more specific approach, the PCR products of 16S rDNA were digested with restriction enzymes. Seven of the samples, including type-strain ATCC 12472, were amplified by the hilA primers; these were subsequently sequenced. Gene yscD was amplified only in type-strain ATCC 12472. MspI and AluI digestion revealed 16S rDNA polymorphisms. This data allowed the generation of a dendogram for each analysis. The isolates of C. violaceum have variability in random genomic regions demonstrated by RAPD. Also, these isolates have variability in pathogenicity genes, as demonstrated by sequencing and restriction enzyme digestion.

Induction of hairy roots by various strains of Agrobacterium rhizogenes in different types of Capsicum species explants

PubMed Central

2014-01-01

Background Capsicum annuum and Capsicum frutescens, also known as “chilies”, belong to the Solanaceae family and have tremendous beneficial properties. The application of hairy root culture may become an alternative method for future development of these species by adding value, such as by increasing secondary metabolites and improving genetic and biochemical stability compared with normal Capsicum plants. Therefore, in this research, different types of explants of both species were infected with various Agrobacterium rhizogenes strains to provide more information about the morphology and induction efficiency of hairy roots. After 2 weeks of in vitro seed germination, young seedling explants were cut into three segments; the cotyledon, hypocotyl, and radical. Then, the explants were co-cultured with four isolated A. rhizogenes strains in Murashige & Skoog culture media (MS) containing decreasing carbenicillin disodium concentrations for one month. Results In this experiment, thick and short hairy roots were induced at all induction sites of C. annuum while thin, elongated hairy roots appeared mostly at wound sites of C. frutescens. Overall, the hairy root induction percentages of C. frutescens were higher compared with C. annuum. Hairy root initiation was observed earliest using radicles (1st week), followed by cotyledons (2nd week), and hypocotyls (3rd week). Cotyledon explants of both species had the highest induction frequency with all strains compared with the other explants types. Strains ATCC 13333 and ATCC 15834 were the most favourable for C. frutescens while ATCC 43056 and ATCC 43057 were the most favourable for C. annuum. The interactions between the different explants and strains showed significant differences with p-values < 0.0001 in both Capsicum species. Conclusions Both Capsicum species were amenable to A. rhizogenes infection and hairy root induction is recommended for use as an alternative explants in future plant-based studies. PMID:24981787

A Novel Ellagic Acid Derivative from Desbordesia glaucescens.

PubMed

DongmoMafodong, Faustine L; Tsopmo, Apollinaire; Awouafack, Maurice D; Roland, Tchuenguem T; Dzoyem, Jean P; Tane, Pierre

2015-10-01

One novel ellagic acid derivative, desglauside (1), was isolated from the leaves of Desbordesia glaucescens together with three known compounds [3',4'-di-O-methylellagic acid (2), oleanolic acid (3) and β-sitosterol-3-O-β-D-glucopyranoside (4)]. Their structures were elucidated on the basis of NMR spectroscopic and MS analysis, and by comparison with related published data. The crude extract, fractions and isolated compounds showed no activity against four yeast strains [Candida albicans (ATCC 9002), C. parapsilopsis (ATCC22019), C. tropicalis (ATCC750), Cryptococcus neoformans (IP95026) and one isolate of Candida guilliermondii].

Evaluation of Nostoc Strain ATCC 53789 as a Potential Source of Natural Pesticides

PubMed Central

Biondi, Natascia; Piccardi, Raffaella; Margheri, M. Cristina; Rodolfi, Liliana; Smith, Geoffrey D.; Tredici, Mario R.

2004-01-01

The cyanobacterium Nostoc strain ATCC 53789, a known cryptophycin producer, was tested for its potential as a source of natural pesticides. The antibacterial, antifungal, insecticidal, nematocidal, and cytotoxic activities of methanolic extracts of the cyanobacterium were evaluated. Among the target organisms, nine fungi (Armillaria sp., Fusarium oxysporum f. sp. melonis, Penicillium expansum, Phytophthora cambivora, P. cinnamomi, Rhizoctonia solani, Rosellinia, sp., Sclerotinia sclerotiorum, and Verticillium albo-atrum) were growth inhibited and one insect (Helicoverpa armigera) was killed by the extract, as well as the two model organisms for nematocidal (Caenorhabditis elegans) and cytotoxic (Artemia salina) activity. No antibacterial activity was detected. The antifungal activity against S. sclerotiorum was further studied with both extracts and biomass of the cyanobacterium in a system involving tomato as a host plant. Finally, the herbicidal activity of Nostoc strain ATCC 53789 was evaluated against a grass mixture. To fully exploit the potential of this cyanobacterium in agriculture as a source of pesticides, suitable application methods to overcome its toxicity toward plants and nontarget organisms must be developed. PMID:15184126

Purification and biochemical characterization of a highly thermostable bacteriocin isolated from Brevibacillus brevis strain GM100.

PubMed

Ghadbane, Mouloud; Harzallah, Daoud; Laribi, Atef Ibn; Jaouadi, Bassem; Belhadj, Hani

2013-01-01

A bacteriocin-producing (11,000 AU mL(-1)) strain was isolated from the rhizosphere of healthy Algerian plants Ononis angustissima Lam., and identified as Brevibacillus brevis strain GM100. The bacteriocin, called Bac-GM100, was purified to homogeneity from the culture supernatant, and, based on MALDI-TOF/MS analysis, was a monomer protein with a molecular mass of 4375.66 Da. The 21 N-terminal residues of Bac-GM100 displayed 65% homology with thurincin H from Bacillus thuringiensis. Bac-GM100 was extremely heat-stable (20 min at 120 °C), and was stable within a pH range of 3-10. It proved sensitive to various proteases, which demonstrated its protein nature. It was also found to display a bactericidal mode of action against gram-negative (Salmonella enteric ATCC 43972, Pseudomonas aeruginosa ATCC 49189, and Agrobacterium tumefaciens C58) and gram-positive (Enterococcus faecalis ENSAIA 631 and Staphylococcus aureus ATCC 6538) bacteria, and a fungistatic mode of action against the pathogenic fungus Candida tropicalis R2 CIP 203.

Composition of the carbohydrate granules of the cyanobacterium, Cyanothece sp. strain ATCC 51142

NASA Technical Reports Server (NTRS)

Schneegurt, M. A.; Sherman, D. M.; Sherman, L. A.; Mitchell, C. A. (Principal Investigator)

1997-01-01

Cyanothece sp. strain ATCC 51142 is an aerobic, unicellular, diazotrophic cyanobacterium that temporally separates O2-sensitive N2 fixation from oxygenic photosynthesis. The energy and reducing power needed for N2 fixation appears to be generated by an active respiratory apparatus that utilizes the contents of large interthylakoidal carbohydrate granules. We report here on the carbohydrate and protein composition of the granules of Cyanothece sp. strain ATCC 51142. The carbohydrate component is a glucose homopolymer with branches every nine residues and is chemically identical to glycogen. Granule-associated protein fractions showed temporal changes in the number of proteins and their abundance during the metabolic oscillations observed under diazotrophic conditions. There also were temporal changes in the protein pattern of the granule-depleted supernatant fractions from diazotrophic cultures. None of the granule-associated proteins crossreacted with antisera directed against several glycogen-metabolizing enzymes or nitrogenase, although these proteins were tentatively identified in supernatant fractions. It is suggested that the granule-associated proteins are structural proteins required to maintain a complex granule architecture.

Mechanism of Nisin, Pediocin 34, and Enterocin FH99 Resistance in Listeria monocytogenes.

PubMed

Kaur, Gurpreet; Singh, Tejinder Pal; Malik, Ravinder Kumar; Bhardwaj, Arun

2012-03-01

Nisin-, pediocin 34-, and enterocin FH99-resistant variants of Listeria monocytogenes ATCC 53135 were developed. In an attempt to clarify the possible mechanisms underlying bacteriocin resistance in L. monocytogenes ATCC 53135, sensitivity of the resistant strains of L. monocytogenes ATCC 53135 to nisin, pediocin 34, and enterocin FH99 in the absence and presence of different divalent cations was assessed, and the results showed that the addition of divalent cations significantly reduced the inhibitory activity of nisin, pediocin 34, and enterocin FH99 against resistant variants of L. monocytogenes ATCC 53135. The addition of EDTA, however, restored this activity suggesting that the divalent cations seem to affect the initial electrostatic interaction between the positively charged bacteriocin and the negatively charged phospholipids of the membrane. Nisin-, pediocin 34-, and enterocin-resistant variants of L. monocytogenes ATCC 53135 were more resistant to lysozyme as compared to the wild-type strain both in the presence as well as absence of nisin, pediocin 34, and enterocin FH99. Ultra structural profiles of bacteriocin-sensitive L. monocytogenes and its bacteriocin-resistant counterparts revealed that the cells of wild-type strain of L. monocytogenes were maximally in pairs or short chains, whereas, its nisin-, pediocin 34-, and enterocin FH99-resistant variants tend to form aggregates. Results indicated that without a cell wall, the acquired nisin, pediocin 34, and enterocin FH99 resistance of the variants was lost. Although the bacteriocin-resistant variants appeared to lose their acquired resistance toward nisin, pediocin 34, and enterocin FH99, the protoplasts of the resistant variants appeared to be more resistant to bacteriocins than the protoplasts of their wild-type counterparts.

In vitro activity of origanum vulgare essential oil against candida species

PubMed Central

Cleff, Marlete Brum; Meinerz, Ana Raquel; Xavier, Melissa; Schuch, Luiz Filipe; Schuch, Luiz Filipe; Araújo Meireles, Mário Carlos; Alves Rodrigues, Maria Regina; de Mello, João Roberto Braga

2010-01-01

The aim of this study was to evaluate the in vitro activity of the essential oil extracted from Origanum vulgare against sixteen Candida species isolates. Standard strains tested comprised C. albicans (ATCC strains 44858, 4053, 18804 and 3691), C. parapsilosis (ATCC 22019), C. krusei (ATCC 34135), C. lusitaniae (ATCC 34449) and C. dubliniensis (ATCC MY646). Six Candida albicans isolates from the vaginal mucous membrane of female dogs, one isolate from the cutaneous tegument of a dog and one isolate of a capuchin monkey were tested in parallel. A broth microdilution technique (CLSI) was used, and the inoculum concentration was adjusted to 5 x 106 CFU mL-1. The essential oil was obtained by hydrodistillation in a Clevenger apparatus and analyzed by gas chromatography. Susceptibility was expressed as Minimal Inhibitory Concentration (MIC) and Minimal Fungicidal Concentration (MFC). All isolates tested in vitro were sensitive to O. vulgare essential oil. The chromatographic analysis revealed that the main compounds present in the essential oil were 4-terpineol (47.95%), carvacrol (9.42%), thymol (8.42%) and □-terpineol (7.57%). C. albicans isolates obtained from animal mucous membranes exhibited MIC and MFC values of 2.72 μL mL-1 and 5 μL mL-1, respectively. MIC and MFC values for C. albicans standard strains were 2.97 μL mL-1 and 3.54 μL mL-1, respectively. The MIC and MFC for non-albicans species were 2.10 μL mL-1 and 2.97 μL mL-1, respectively. The antifungal activity of O. vulgare essential oil against Candida spp. observed in vitro suggests its administration may represent an alternative treatment for candidiasis. PMID:24031471

Co-culturing a novel Bacillus strain with Clostridium tyrobutyricum ATCC 25755 to produce butyric acid from sucrose

PubMed Central

2013-01-01

Background Currently, the most promising microorganism used for the bio-production of butyric acid is Clostridium tyrobutyricum ATCC 25755T; however, it is unable to use sucrose as a sole carbon source. Consequently, a newly isolated strain, Bacillus sp. SGP1, that was found to produce a levansucrase enzyme, which hydrolyzes sucrose into fructose and glucose, was used in a co-culture with this strain, permitting C. tyrobutyricum ATCC 25755T to ferment sucrose to butyric acid. Results B. sp. SGP1 alone did not show any butyric acid production and the main metabolite produced was lactic acid. This allowed C. tyrobutyricum ATCC 25755T to utilize the monosaccharides resulting from the activity of levansucrase together with the lactic acid produced by B. sp. SGP1 to generate butyric acid, which was the main fermentative product within the co-culture. Furthermore, the final acetic acid concentration in the co-culture was significantly lower when compared with pure C. tyrobutyricum ATCC 25755T cultures grown on glucose. In fed-batch fermentations, the optimum conditions for the production of butyric acid were around pH 5.50 and a temperature of 37°C. Under these conditions, the final butyrate concentration was 34.2±1.8 g/L with yields of 0.35±0.03 g butyrate/g sucrose and maximum productivity of 0.3±0.04 g/L/h. Conclusions Using this co-culture, sucrose can be utilized as a carbon source for butyric acid production at a relatively high yield. In addition, this co-culture offers also the benefit of a greater selectivity, with butyric acid constituting 92.8% of the acids when the fermentation was terminated. PMID:23452443

Co-culturing a novel Bacillus strain with Clostridium tyrobutyricum ATCC 25755 to produce butyric acid from sucrose.

PubMed

Dwidar, Mohammed; Kim, Seil; Jeon, Byoung Seung; Um, Youngsoon; Mitchell, Robert J; Sang, Byoung-In

2013-03-04

Currently, the most promising microorganism used for the bio-production of butyric acid is Clostridium tyrobutyricum ATCC 25755T; however, it is unable to use sucrose as a sole carbon source. Consequently, a newly isolated strain, Bacillus sp. SGP1, that was found to produce a levansucrase enzyme, which hydrolyzes sucrose into fructose and glucose, was used in a co-culture with this strain, permitting C. tyrobutyricum ATCC 25755T to ferment sucrose to butyric acid. B. sp. SGP1 alone did not show any butyric acid production and the main metabolite produced was lactic acid. This allowed C. tyrobutyricum ATCC 25755T to utilize the monosaccharides resulting from the activity of levansucrase together with the lactic acid produced by B. sp. SGP1 to generate butyric acid, which was the main fermentative product within the co-culture. Furthermore, the final acetic acid concentration in the co-culture was significantly lower when compared with pure C. tyrobutyricum ATCC 25755T cultures grown on glucose. In fed-batch fermentations, the optimum conditions for the production of butyric acid were around pH 5.50 and a temperature of 37°C. Under these conditions, the final butyrate concentration was 34.2±1.8 g/L with yields of 0.35±0.03 g butyrate/g sucrose and maximum productivity of 0.3±0.04 g/L/h. Using this co-culture, sucrose can be utilized as a carbon source for butyric acid production at a relatively high yield. In addition, this co-culture offers also the benefit of a greater selectivity, with butyric acid constituting 92.8% of the acids when the fermentation was terminated.

Draft Genome Sequence of Thiostrepton-Producing Streptomyces azureus ATCC 14921

PubMed Central

Sakihara, Kengo; Maeda, Jumpei; Tashiro, Kosuke; Fujino, Yasuhiro; Kuhara, Satoru; Ohshima, Toshihisa; Ogata, Seiya

2015-01-01

Streptomyces azureus ATCC 14921 belongs to the Streptomyces cyaneus cluster and is known to be a thiostrepton producer. Here, we report a draft genome sequence for this strain, consisting of 350 contigs containing a total of 8,790,525 bp, 8,164 predicted coding sequences, and a G+C content of 70.9%. PMID:26494661

Zn(II), Ni(II), Cu(II) and Pb(II) complexes of tridentate asymmetrical Schiff base ligands: Synthesis, characterization, properties and biological activity

NASA Astrophysics Data System (ADS)

Şahin, Mustafa; Koçak, Nuriye; Erdenay, Damla; Arslan, Uğur

2013-02-01

New asymmetrical tridentate Schiff base ligands were synthesized using 1,2-phenylenediamine, 4-methyl-1,2-phenylenediamine, 2-hydroxy-1-napthaldehyde, 9-anthracenecarboxaldehyde. Schiff base ligands and their metal complexes were synthesised and characterized by using FT-IR, 1H NMR, 13C NMR, UV-Vis, XRD, ESR, elemental analysis and fluorescence studies. The antimicrobial activity of the ligands and their metal complexes were studied against Staphylococcus aureus ATCC 29213, S. aureus ATCC 25923, Streptococcus mutans RSHM 676, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853. The determination of the antibacterial activity was done using the broth microdilution methods. In general, it has been determined that the studied compounds have MIC values similar to Gram-positive and Gram-negative bacteria. It has been found that Ni, Pb, Zn derivatives of HL1A and ZnL2A has lower MIC values than ampicillin for P. aeruginosa ATCC 27853 strain.

Genome sequence and plasmid transformation of the model high-yield bacterial cellulose producer Gluconacetobacter hansenii ATCC 53582

NASA Astrophysics Data System (ADS)

Florea, Michael; Reeve, Benjamin; Abbott, James; Freemont, Paul S.; Ellis, Tom

2016-03-01

Bacterial cellulose is a strong, highly pure form of cellulose that is used in a range of applications in industry, consumer goods and medicine. Gluconacetobacter hansenii ATCC 53582 is one of the highest reported bacterial cellulose producing strains and has been used as a model organism in numerous studies of bacterial cellulose production and studies aiming to increased cellulose productivity. Here we present a high-quality draft genome sequence for G. hansenii ATCC 53582 and find that in addition to the previously described cellulose synthase operon, ATCC 53582 contains two additional cellulose synthase operons and several previously undescribed genes associated with cellulose production. In parallel, we also develop optimized protocols and identify plasmid backbones suitable for transformation of ATCC 53582, albeit with low efficiencies. Together, these results provide important information for further studies into cellulose synthesis and for future studies aiming to genetically engineer G. hansenii ATCC 53582 for increased cellulose productivity.

Rickettsia gravesii sp. nov.: a novel spotted fever group rickettsia in Western Australian Amblyomma triguttatum triguttatum ticks.

PubMed

Abdad, Mohammad Y; Abdallah, Rita Abou; Karkouri, Khalid El; Beye, Mamadou; Stenos, John; Owen, Helen; Unsworth, Nathan; Robertson, Ian; Blacksell, Stuart D; Nguyen, Thi-Tien; Nappez, Claude; Raoult, Didier; Fenwick, Stan; Fournier, Pierre-Edouard

2017-09-01

A rickettsial organism harboured by Amblyomma triguttatum ticks on Barrow Island, Western Australia, was discovered after reports of possible rickettsiosis among local workers. Subsequent isolation of this rickettsia (strain BWI-1) in cell culture and analysis of its phylogenetic, genotypic and phenotypic relationships with type strains of Rickettsia species with standing in nomenclature suggested that it was sufficiently divergent to warrant its classification as a new species. Multiple gene comparison of strain BWI-1 revealed degrees of sequence similarity with Rickettsia raoultii, its closest relative, of 99.58, 98.89, 97.03, 96.93 and 95.73 % for the 16S rRNA, citrate synthase, ompA, ompB and sca4 genes, respectively. Serotyping in mice also demonstrated that strain BWI-1T was distinct from Rickettsia raoultii. Thus, we propose the naming of a new species, Rickettsia gravesii sp. nov., based on its novel genotypic and phenotypic characteristics. Strain BWI-1T was deposited in the ATCC, CSUR and ARRL collections under reference numbers VR-1664, CSUR R172 and RGBWI-1, respectively.

Organization and characterization of genetic regions in Bacillus subtilis subsp. krictiensis ATCC55079 associated with the biosynthesis of iturin and surfactin compounds

PubMed Central

Kim, Sung Eun; Lee, Won Jung; Moon, Jae Sun; Cho, Min Seop; Park, Ho-Yong; Hwang, Ingyu

2017-01-01

Bacillus subtilis subsp. krictiensis ATCC55079 produces the cyclic lipopeptide antibiotics iturin A–F as well as several surfactins. Here, we analyzed and characterized the biosynthetic genes associated with iturin and surfactin production in this strain. We aligned the sequences of each iturin and surfactin synthetase ORF obtained from a genomic library screen and next generation sequencing. The resulting 37,249-bp and 37,645-bp sequences associated with iturin and surfactin production, respectively, contained several ORFs that are predicted to encode proteins involved in iturin and surfactin biosynthesis. These ORFs showed higher sequence homologies with the respective iturin and surfactin synthetase genes of B. methylotrophicus CAU B946 than with those of B. subtilis RB14 and B. subtilis ATCC6633. Moreover, comparative analysis of the secondary metabolites produced by the wild-type and surfactin-less mutant (with a spectinomycin resistance cassette inserted into the srfAB gene within the putative surfactin gene region) strains demonstrated that the mutant strain showed significantly higher antifungal activity against Fusarium oxysporum than the wild-type strain. In addition, the wild-type strain-specific surfactin high performance liquid chromatography (HPLC) peaks were not observed in the surfactin-less mutant strain. In contrast, the iturin A peak detected by HPLC and liquid chromatography-mass spectrometry (LC/MS) in the surfactin-less mutant strain was 30% greater than that in the wild-type strain. These results suggested that the gene cluster we identified is involved in surfactin biosynthesis, and the biosynthetic pathways for iturin and surfactin in Bacillus strains producing both iturin and surfactin may utilize a common pathway. PMID:29267290

Resistance of enterococci to heat and chemical agents.

PubMed

Renner, P; Peters, J

1999-06-01

Within the framework of the standardisation efforts on disinfectant testing on the European level the test germ Enterococcus hirae ATCC 10541 has been included for some time in the test requirements whereas the test strain Enterococcus faecium, which has frequently been used up to now, has been largely ignored. We compared the thermal and the chemical resistance of both test germ species. In the quantitative suspension test with active ingredients from the group of aldehydes, phenols, quaternaries and oxidizing agents with the exception of peracetic acid, no significant differences were determined between the two strains. In the case of the studies on thermal resistance at 65 degrees C and 68 degrees C, Enterococcus faecium ATCC 6057, by contrast, proved to be far more resistant than Enterococcus hirae ATCC 10541. According to these results, priority should be given to Enterococcus faecium over Enterococcus hirae as the test germ for chemical and also chemothermal disinfection.

Anti-Helicobacter pylori activities of selected N-substituted cinnamamide derivatives evaluated on reference and clinical bacterial strains.

PubMed

Klesiewicz, Karolina; Karczewska, Elżbieta; Nowak, Paweł; Skiba-Kurek, Iwona; Sito, Edward; Pańczyk, Katarzyna; Koczurkiewicz, Paulina; Żelaszczyk, Dorota; Pękala, Elżbieta; Waszkielewicz, Anna M; Budak, Alicja; Marona, Henryk; Gunia-Krzyżak, Agnieszka

2018-05-01

In this study, thirty-five N-substituted derivatives of cinnamic acid amide (cinnamamide) were evaluated for anti-Helicobacter pylori activity using an agar disc-diffusion method. Qualitative screening was performed on a reference H. pylori strain (ATCC 43504), resulting in the identification of the three most active compounds, 8 (R,S-(2E)-3-(4-chlorophenyl)-N-(2-hydroxypropyl)prop-2-enamide, minimal inhibitory concentration, MIC = 7.5 µg/mL), 23 ((2E)-3-(4-chlorophenyl)-N-(2-hydroxycyclohexyl)prop-2-enamide, MIC = 10 µg/mL), and 28 ((2E)-3-(4-chlorophenyl)-N-(4-oxocyclohexyl)prop-2-enamide, MIC = 10 µg/mL). These compounds were further tested on twelve well-characterized clinical strains, yielding MIC values that ranged from 10 to 1000 µg/mL. Preliminary safety assessments of the compounds were made using the MTT viability test for cytotoxicity and Ames test for mutagenicity, which showed them to be generally safe, although compounds 8 and 28 showed mutagenic activity at some of the tested concentrations. The results of this study showed the anti-H. pylori potential of cinnamamide derivatives.

Rate of penicillin killing of Staphylococcus aureus and Autobac 1 susceptibility test results.

PubMed Central

Harris, J A; Furtado, D

1982-01-01

A clinical isolate of Staphylococcus aureus interpreted as resistant to penicillin by the Autobac 1 susceptibility testing method (i.e., light-scattering index of 0.77) was found to be susceptible to penicillin by both the disk diffusion and broth dilution techniques. The growth rate of the clinical isolate during a 4-h incubation interval was similar to that of a known sensitive reference strain (S. aureus ATCC 25923) used as a control organism for the Autobac test. The bactericidal effect of penicillin was evaluated by measuring the rate of killing over a 4-h interval. The percentages of organisms surviving exposure to 5.0 or 2.5 U of penicillin G per ml (number of organisms recovered at 3 h/number of organisms introduced as inoculum) were 68 and 76%, respectively, for the clinical isolate and 15 and 21%, respectively, for the reference strain. After 24 h of incubation, penicillin was bactericidal for both strains. The need to increase the time of incubation for those S. aureus isolates resistant to penicillin after 3 h of standard incubation time in the Autobac system is discussed. PMID:7068821

Inhibitory effect of lactoperoxidase-generated hypothiocyanite upon black pigmented anaerobe growth.

PubMed

Fadel, M; Courtois, P

2001-07-01

This study aimed to evaluate the in vitro effect of lactoperoxidase with or without its substrates (hydrogen peroxide, thiocyanate) on the growth of 4 different black pigmented anaerobe (BPA) strains associated with the development and progress of periodontal diseases: Porphyromonas gingivalis ATCC 33277, Prevotella intermedia NCTC 9336, Prevotella loescheii ATCC 15930, and Prevotella melaninogenica NCTC 9338. A 5-min lactoperoxidase-generated OSCN--HOSCN incubation at pH 6.0, 7.0 or 8.0 resulted in a decrease of the growth rate (tested by turbidimetry in liquid cultures) of the 4 BPA strains, whilst lactoperoxidase alone actually promoted bacterial growth.

Sellimonas intestinalis gen. nov., sp. nov., isolated from human faeces.

PubMed

Seo, Boram; Yoo, Ju Eun; Lee, Yung Mi; Ko, GwangPyo

2016-02-01

A Gram-stain-positive and obligately anaerobic bacterial strain, BR72 T , forming ivory yellow colonies was isolated from a faecal sample of a healthy Korean woman. 16S rRNA gene sequence analysis indicated that strain BR72 T belongs to Clostridium cluster XIVa and represents a distinct phyletic line within the family Lachnospiraceae . The most closely related strains were Clostridium nexile DSM 1787 T (94.1 % 16S rRNA gene sequence similarity), Coprococcus comes ATCC 27758 T (93.5 %), Ruminococcus torques ATCC 27756 T (93.5 %), Ruminococcus lactaris ATCC 29176 T (93.5 %), Clostridium aerotolerans DSM 5434 T (93.1 %) and Eubacterium fissicatena DSM 3598 T (92.9 %). The DNA G+C content of strain BR72 T based on its genome sequence was 45.3 mol%. The major cellular fatty acids were C 16 : 0 , C 14 : 0 , and iso-C 17 : 1 I and/or anteiso-C 17 : 1 B. Acetic acid was produced from glucose fermentation. Other physiological and biochemical comparisons allowed the phenotypic differentiation of strain BR72 T from the members of the family Lachnospiraceae . Based on the phylogenetic and phenotypic findings, this strain is considered to represent a novel species of a new genus belonging to the family Lachnospiraceae and the name Sellimonas intestinalis gen. nov., sp. nov. is proposed. The type strain of Sellimonas intestinalis is BR72 T ( = KCTC 15479 T  = JCM 30749 T ).

Microbial strain improvement for enhanced polygalacturonase production by Aspergillus sojae.

PubMed

Heerd, Doreen; Tari, Canan; Fernández-Lahore, Marcelo

2014-09-01

Strain improvement is a powerful tool in commercial development of microbial fermentation processes. Strains of Aspergillus sojae which were previously identified as polygalacturonase producers were subjected to the cost-effective mutagenesis and selection method, the so-called random screening. Physical (ultraviolet irradiation at 254 nm) and chemical mutagens (N-methyl-N'-nitro-N-nitrosoguanidine) were used in the development and implementation of a classical mutation and selection strategy for the improved production of pectic acid-degrading enzymes. Three mutation cycles of both mutagenic treatments and also the combination of them were performed to generate mutants descending from A. sojae ATCC 20235 and mutants of A. sojae CBS 100928. Pectinolytic enzyme production of the mutants was compared to their wild types in submerged and solid-state fermentation. Comparing both strains, higher pectinase activity was obtained by A. sojae ATCC 20235 and mutants thereof. The highest polygalacturonase activity (1,087.2 ± 151.9 U/g) in solid-state culture was obtained by mutant M3, which was 1.7 times increased in comparison to the wild strain, A. sojae ATCC 20235. Additional, further mutation of mutant M3 for two more cycles of treatment by UV irradiation generated mutant DH56 with the highest polygalacturonase activity (98.8 ± 8.7 U/mL) in submerged culture. This corresponded to 2.4-fold enhanced polygalacturonase production in comparison to the wild strain. The results of this study indicated the development of a classical mutation and selection strategy as a promising tool to improve pectinolytic enzyme production by both fungal strains.

Thermal inactivation kinetics of Bacillus coagulans spores in tomato juice.

PubMed

Peng, Jing; Mah, Jae-Hyung; Somavat, Romel; Mohamed, Hussein; Sastry, Sudhir; Tang, Juming

2012-07-01

The thermal characteristics of the spores and vegetative cells of three strains of Bacillus coagulans (ATCC 8038, ATCC 7050, and 185A) in tomato juice were evaluated. B. coagulans ATCC 8038 was chosen as the target microorganism for thermal processing of tomato products due to its spores having the highest thermal resistance among the three strains. The thermal inactivation kinetics of B. coagulans ATCC 8038 spores in tomato juice between 95 and 115°C were determined independently in two different laboratories using two different heating setups. The results obtained from both laboratories were in general agreement, with z-values (z-value is defined as the change in temperature required for a 10-fold reduction of the D-value, which is defined as the time required at a certain temperature for a 1-log reduction of the target microorganisms) of 8.3 and 8.7°C, respectively. The z-value of B. coagulans 185A spores in tomato juice (pH 4.3) was found to be 10.2°C. The influence of environmental factors, including cold storage time, pH, and preconditioning, upon the thermal resistance of these bacterial spores is discussed. The results obtained showed that a storage temperature of 4°C was appropriate for maintaining the viability and thermal resistance of B. coagulans ATCC 8038 spores. Acidifying the pH of tomato juice decreased the thermal resistance of these spores. A 1-h exposure at room temperature was considered optimal for preconditioning B. coagulans ATCC 8038 spores in tomato juice.

Thymoquinone Inhibits Virulence Related Traits of Cronobacter sakazakii ATCC 29544 and Has Anti-biofilm Formation Potential.

PubMed

Shi, Chao; Yan, Chunhong; Sui, Yue; Sun, Yi; Guo, Du; Chen, Yifei; Jin, Tong; Peng, Xiaoli; Ma, Linlin; Xia, Xiaodong

2017-01-01

The aim of this study was to determine whether thymoquinone, the principal active ingredient in the volatile oil of Nigella sativa seeds, could suppress certain virulence traits of Cronobacter sakazakii ATCC 29544 which contribute to infection. Sub-inhibitory concentrations of thymoquinone significantly decreased motility, quorum sensing, and endotoxin production of C. sakazakii ATCC 29544 and biofilm formation of C. sakazakii 7-17. Thymoquinone substantially reduced the adhesion and invasion of C. sakazakii ATCC 29544 to HT-29 cells and decreased the number of intracellular bacterial cells within the RAW 264.7 macrophage cells. Thymoquinone also repressed the transcription of sixteen genes involved in the virulence. These findings suggest that thymoquinone could attenuated virulence-related traits of C. sakazakii ATCC 29544, and its effects on other C. sakazakii strains and in vivo C. sakazakii infection need further investigation.

Thymoquinone Inhibits Virulence Related Traits of Cronobacter sakazakii ATCC 29544 and Has Anti-biofilm Formation Potential

PubMed Central

Shi, Chao; Yan, Chunhong; Sui, Yue; Sun, Yi; Guo, Du; Chen, Yifei; Jin, Tong; Peng, Xiaoli; Ma, Linlin; Xia, Xiaodong

2017-01-01

The aim of this study was to determine whether thymoquinone, the principal active ingredient in the volatile oil of Nigella sativa seeds, could suppress certain virulence traits of Cronobacter sakazakii ATCC 29544 which contribute to infection. Sub-inhibitory concentrations of thymoquinone significantly decreased motility, quorum sensing, and endotoxin production of C. sakazakii ATCC 29544 and biofilm formation of C. sakazakii 7-17. Thymoquinone substantially reduced the adhesion and invasion of C. sakazakii ATCC 29544 to HT-29 cells and decreased the number of intracellular bacterial cells within the RAW 264.7 macrophage cells. Thymoquinone also repressed the transcription of sixteen genes involved in the virulence. These findings suggest that thymoquinone could attenuated virulence-related traits of C. sakazakii ATCC 29544, and its effects on other C. sakazakii strains and in vivo C. sakazakii infection need further investigation. PMID:29234307

Comparison of culture, PCR, and different serologic tests for detection of Mycoplasma gallisepticum and Mycoplasma synoviae infections.

PubMed

Feberwee, A; Mekkes, D R; de Wit, J J; Hartman, E G; Pijpers, A

2005-06-01

In this study, the technical performance of culture, two commercially available polymerase chain reaction (PCR) tests, rapid plate agglutination (RPA) test, hemagglutination inhibition (HI) test, and eight commercially available enzyme-linked immunosorbent assays (ELISAs) were compared for the detection of avian mycoplasma infections from 3 days postinfection (d.p.i.) through 35 d.p.i. The tests were carried out on samples from specified pathogen-free layers that were infected at 66 wk of age with recent Mycoplasma synoviae (MS) and Mycoplasma gallisepticum (MG) field strains, MS and MG ATCC strains, and Mycoplasma imitans (MIM), respectively. Results showed a high percentage of positive samples in the homologous infected groups and a high percentage of negative samples (100%) in the uninfected and heterologous infected groups during 35 d.p.i. of both culture and PCR tests. For the group infected with the MG 15302 ATCC strain, serology was more sensitive than bacteriology. All MG and MS tests, with the exception of MG ELISA kit D showed a lower percentage of positive samples during 35 d.p.i. for the detection of the MG and MS ATCC strain infection compared with that of the field strains. Also, the number of cross-reactions (false positives) in the serologic tests was lower after infection with an ATCC strain than after an infection with the MG or MS field strain. Contradictory to other studies, the ELISAs and the RPA test using undiluted serum showed a relatively high number of false-positive results. The MG ELISAs (except ELISA kit D) showed more false-positive results (up to 37%) in the MIM-infected group than in the MS-infected groups. This was not unexpected, as MIM and MG have a close antigenic relationship. The results of the serologic tests in this study showed that a certain level of false-positive results can be expected in about any serologic test. Although the level of false-positive results varied between several serologic tests, this study showed that it is not advisable to rely completely on one test (system) only.

Efficiency of four currently used decontamination conditionings in Romania against Aspergillus and Candida strains.

PubMed

Lorin, D; Cristina, R T; Teusdea, V; Mitrănescu, E; Muselin, F; Butnariu, M; David, G; Dumitrescu, E

2017-09-01

Efficacy of four commercial biocidal products (noted A to D), using manufacturers' recommendations, and a contact time of 30minutes, were evaluated in the purpose of standard SR EN1657: 2006 adapted. Were used four strains, two as reference: Aspergillus brasiliensis (niger) (ATCC 16404) and Candida albicans (ATCC 10231), and two isolates: Aspergillus flavus and respectively Aspergillus fumigatus. The inoculum plates containing Malt Extract Agar (MEA) were incubated 48h for C. albicans and 72hours for Aspergillus spp. The standard SR EN1657: 2006 adapted was conducted in two phases: the test cultures preparation and the method validation. Method validation included: the control of experimental conditions and of neutralizant solution, and the method verification. Results revealed that three from the four tested products (A, B and D) had exerted biocidal effect on the studied strains at the recommended concentrations, the registered CFU values being reduced by more than 4 log 10 , conversely in the case of the product (C), applied against A. fumigatus at the recommended concentration of 2%, the biocidal effect was not detected, fact confirmed also by the CFU's value (3.59 log 10 ). The biocide retested at a greater concentration (of 5%), showed a biocidal effect against A. fumigatus after 30minutes, the CFU value being reduced, by more than 5.29 log 10 , evidencing the resistance emergence of A. fumigatus under the repeated pressure of biocides. It is re-confirming that merely the "chemical" defense measures to defuse the fungi's strategies become unproductive. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Homologous stress adaptation, antibiotic resistance, and biofilm forming ability of Salmonella enterica serovar Heidelberg (ATCC8326) on different food-contact surfaces following exposure to sub-lethal chlorine concentrations

USDA-ARS?s Scientific Manuscript database

Salmonella enterica serovar Heidelberg (American Type Culture Collection; ATCC 8326) was examined for the ability to adapt to the homologous stress of chlorine through exposure to increasing chlorine concentrations (25 ppm daily increments) in tryptic soy broth (TSB). The tested strain exhibited an ...

Effect of Lactobacillus brevis ATCC 8287 as a feeding supplement on the performance and immune function of piglets

USDA-ARS?s Scientific Manuscript database

Lactobacillus brevis ATCC 8287, a surface (S-layer) strain, possesses a variety of functional properties that make it both a potential probiotic and a good vaccine vector candidate. With this in mind, our aim was to study the survival of L. brevis in the porcine gut and investigate the effect of th...

Cationic synthetic peptides: assessment of their antimicrobial potency in liquid preserved boar semen.

PubMed

Speck, Stephanie; Courtiol, Alexandre; Junkes, Christof; Dathe, Margitta; Müller, Karin; Schulze, Martin

2014-01-01

Various semen extender formulas are in use to maintain sperm longevity and quality whilst acting against bacterial contamination in liquid sperm preservation. Aminoglycosides are commonly supplemented to aid in the control of bacteria. As bacterial resistance is increasing worldwide, antimicrobial peptides (AMPs) received lively interest as alternatives to overcome multi-drug resistant bacteria. We investigated, whether synthetic cationic AMPs might be a suitable alternative for conventional antibiotics in liquid boar sperm preservation. The antibacterial activity of two cyclic AMPs (c-WWW, c-WFW) and a helical magainin II amide analog (MK5E) was studied in vitro against two Gram-positive and eleven Gram-negative bacteria. Isolates included ATCC reference strains, multi-resistant E. coli and bacteria cultured from boar semen. Using broth microdilution, minimum inhibitory concentrations were determined for all AMPs. All AMPs revealed activity towards the majority of bacteria but not against Proteus spp. (all AMPs) and Staphylococcus aureus ATCC 29213 (MK5E). We could also demonstrate that c-WWW and c-WFW were effective against bacterial growth in liquid preserved boar semen in situ, especially when combined with a small amount of gentamicin. Our results suggest that albeit not offering a complete alternative to traditional antibiotics, the use of AMPs offers a promising solution to decrease the use of conventional antibiotics and thereby limit the selection of multi-resistant strains.

Cationic Synthetic Peptides: Assessment of Their Antimicrobial Potency in Liquid Preserved Boar Semen

PubMed Central

Speck, Stephanie; Courtiol, Alexandre; Junkes, Christof; Dathe, Margitta; Müller, Karin; Schulze, Martin

2014-01-01

Various semen extender formulas are in use to maintain sperm longevity and quality whilst acting against bacterial contamination in liquid sperm preservation. Aminoglycosides are commonly supplemented to aid in the control of bacteria. As bacterial resistance is increasing worldwide, antimicrobial peptides (AMPs) received lively interest as alternatives to overcome multi-drug resistant bacteria. We investigated, whether synthetic cationic AMPs might be a suitable alternative for conventional antibiotics in liquid boar sperm preservation. The antibacterial activity of two cyclic AMPs (c-WWW, c-WFW) and a helical magainin II amide analog (MK5E) was studied in vitro against two Gram-positive and eleven Gram-negative bacteria. Isolates included ATCC reference strains, multi-resistant E. coli and bacteria cultured from boar semen. Using broth microdilution, minimum inhibitory concentrations were determined for all AMPs. All AMPs revealed activity towards the majority of bacteria but not against Proteus spp. (all AMPs) and Staphylococcus aureus ATCC 29213 (MK5E). We could also demonstrate that c-WWW and c-WFW were effective against bacterial growth in liquid preserved boar semen in situ, especially when combined with a small amount of gentamicin. Our results suggest that albeit not offering a complete alternative to traditional antibiotics, the use of AMPs offers a promising solution to decrease the use of conventional antibiotics and thereby limit the selection of multi-resistant strains. PMID:25148109

Transcriptome analysis of Cronobacter sakazakii ATCC BAA-894 after interaction with human intestinal epithelial cell line HCT-8.

PubMed

Jing, Chun-e; Du, Xin-jun; Li, Ping; Wang, Shuo

2016-01-01

Cronobacter spp. are opportunistic pathogens that are responsible for infections including severe meningitis, septicemia, and necrotizing enterocolitis in neonates and infants. To date, questions still remain regarding the mechanisms of pathogenicity and virulence determinants for each bacterial strain. In this study, we established an in vitro model for Cronobacter sakazakii ATCC BAA-894 infection of HCT-8 human colorectal epithelial cells. The transcriptome profile of C. sakazakii ATCC BAA-894 after interaction with HCT-8 cells was determined using high-throughput whole-transcriptome sequencing (RNA sequencing (RNA-seq)). Gene expression profiles indicated that 139 genes were upregulated and 72 genes were downregulated in the adherent C. sakazakii ATCC BAA-894 strain on HCT-8 cells compared to the cultured bacteria in the cell-free medium. Expressions of some flagella genes and virulence factors involved in adherence were upregulated. High osmolarity and osmotic stress-associated genes were highly upregulated, as well as genes responsible for the synthesis of lipopolysaccharides and outer membrane proteins, iron acquisition systems, and glycerol and glycerophospholipid metabolism. In sum, our study provides further insight into the mechanisms underlying C. sakazakii pathogenesis in the human gastrointestinal tract.

Gallium Compounds Exhibit Potential as New Therapeutic Agents against Mycobacterium abscessus

PubMed Central

Abdalla, Maher Y.; Switzer, Barbara L.; Goss, Christopher H.; Aitken, Moira L.; Singh, Pradeep K.

2015-01-01

The rapidly growing nontuberculous mycobacterial species Mycobacterium abscessus has recently emerged as an important pathogen in patients with cystic fibrosis (CF). Treatment options are limited because of the organism's innate resistance to standard antituberculous antibiotics, as well as other currently available antibiotics. New antibiotic approaches to the treatment of M. abscessus are urgently needed. The goal of the present study was to assess the growth-inhibitory activity of different Ga compounds against an American Type Culture Collection (ATCC) strain and clinical isolates of M. abscessus obtained from CF and other patients. In our results, using Ga(NO3)3 and all of the other Ga compounds tested inhibited the growth of ATCC 19977 and clinical isolates of M. abscessus. Inhibition was mediated by disrupting iron uptake, as the addition of exogenous iron (Fe) restored basal growth. There were modest differences in inhibition among the isolates for the same Ga chelates, and for most Ga chelates there was only a slight difference in potency from Ga(NO3)3. In contrast, Ga-protoporphyrin completely and significantly inhibited the ATCC strain and clinical isolates of M. abscessus at much lower concentrations than Ga(NO3)3. In in vitro broth culture, Ga-protoporphyrin was more potent than Ga(NO3)3. When M. abscessus growth inside the human macrophage THP-1 cell line was assessed, Ga-protoporphyrin was >20 times more active than Ga(NO3)3. The present work suggests that Ga exhibits potent growth-inhibitory capacity against the ATCC strain, as well as against antibiotic-resistant clinical isolates of M. abscessus, including the highly antibiotic-resistant strain MC2638. Ga-based therapy offers the potential for further development as a novel therapy against M. abscessus. PMID:26033732

Vagococcus carniphilus sp. nov., isolated from ground beef.

PubMed

Shewmaker, P Lynn; Steigerwalt, Arnold G; Morey, Roger E; Carvalho, Maria da Glória S; Elliott, John A; Joyce, Kevin; Barrett, Timothy J; Teixeira, Lucia M; Facklam, Richard R

2004-09-01

Nine enterococcus-like strains were referred to the Streptococcus Laboratory at the Centers for Disease Control and Prevention (CDC) for further identification from the National Antimicrobial Resistance Monitoring System Laboratory at the CDC. The cultures were isolated from ground beef purchased from retail in Oregon in 2000. Conventional biochemical testing and analysis of whole-cell protein electrophoretic profiles distinguished these strains from known species of enterococci and vagococci. Comparative 16S rRNA gene sequencing studies revealed that these strains were most closely related to the species Vagococcus fluvialis. DNA-DNA reassociation studies confirmed that these nine strains represented a new taxon. The relative binding ratio was 87 % or greater at the optimal temperature, and the divergence was less than 1 % for strains hybridized against the isolate designated the type strain. DNA-DNA relatedness was 25 % to V. fluvialis and 9 % or less to the other three species of Vagococcus. DNA-DNA relatedness was 33 % or less to the 25 currently described species of Enterococcus. On the basis of this evidence, it is proposed that these strains be classified as Vagococcus carniphilus sp. nov. The type strain of V. carniphilus is 1843-02T (= ATCC BAA-640T = CCUG 46823T). The clinical significance (if any) of these strains is yet to be determined.

Antifungal activity and cytotoxicity of extracts and triterpenoid saponins obtained from the aerial parts of Anagallis arvensis L.

PubMed

Soberón, José R; Sgariglia, Melina A; Pastoriza, Ana C; Soruco, Estela M; Jäger, Sebastián N; Labadie, Guillermo R; Sampietro, Diego A; Vattuone, Marta A

2017-05-05

Anagallis arvensis L. (Primulaceae) is used in argentinean northwestern traditional medicine to treat fungal infections. We are reporting the isolation and identification of compounds with antifungal activity against human pathogenic yeast Candida albicans, and toxicity evaluation. to study the antifungal activity of extracts and purified compounds obtained form A. arvensis aerial parts, alone and in combinations with fluconazole (FLU), and to study the toxicity of the active compounds. Disk diffusion assays were used to perform an activity-guided isolation of antifungal compounds from the aerial parts of A. arvensis. Broth dilution checkerboard and viable cell count assays were employed to determine the effects of samples and combinations of FLU + samples against Candida albicans. The chemical structures of active compounds were elucidated by spectroscopic analysis. Genotoxic and haemolytic effects of the isolated compounds were determined. Four triterpenoid saponins (1-4) were identified. Anagallisin C (AnC), exerted the highest inhibitory activity among the assayed compounds against C. albicans reference strain (ATCC 10231), with MIC-0 =1µg/mL. The Fractional Inhibitory Concentration Index (FICI=0.129) indicated a synergistic effect between AnC (0.125µg/mL) and FLU (0.031µg/mL) against C. albicans ATCC 10231. AnC inhibited C. albicans 12-99 FLU resistant strain (MIC-0 =1µg/mL), and the FICI=0.188 indicated a synergistic effect between AnC (0.125µg/mL) and fluconazole (16µg/mL). The combination AnC+ FLU exerted fungicidal activity against both C. albicans strains. AnC exerted inhibitory activity against C. albicans ATCC 10231 sessile cells (MIC 5 0=0.5µg/mL and MIC 80 =1µg/mL) and against C. albicans 12-99 sessile cells (MIC 5 0=0.75µg/mL and MIC 80 =1.25µg/mL). AnC exerted haemolytic effect against human red blood cells at 15µg/mL and did not exerted genotoxic effect on Bacillus subtilis rec strains. The antifungal activity and lack of genotoxic effects of AnC give support to the traditional use of A. arvensis as antifungal and makes AnC a compound of interest to expand the available antifungal drugs. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Lactic acid bacteria: promising supplements for enhancing the biological activities of kombucha.

PubMed

Nguyen, Nguyen Khoi; Dong, Ngan Thi Ngoc; Nguyen, Huong Thuy; Le, Phu Hong

2015-01-01

Kombucha is sweetened black tea that is fermented by a symbiosis of bacteria and yeast embedded within a cellulose membrane. It is considered a health drink in many countries because it is a rich source of vitamins and may have other health benefits. It has previously been reported that adding lactic acid bacteria (Lactobacillus) strains to kombucha can enhance its biological functions, but in that study only lactic acid bacteria isolated from kefir grains were tested. There are many other natural sources of lactic acid bacteria. In this study, we examined the effects of lactic acid bacteria from various fermented Vietnamese food sources (pickled cabbage, kefir and kombucha) on kombucha's three main biological functions: glucuronic acid production, antibacterial activity and antioxidant ability. Glucuronic acid production was determined by high-performance liquid chromatography-mass spectrometry, antibacterial activity was assessed by the agar-well diffusion method and antioxidant ability was evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity. Four strains of food-borne pathogenic bacteria were used in our antibacterial experiments: Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 8739, Salmonella typhimurium ATCC 14028 and Bacillus cereus ATCC 11778. Our findings showed that lactic acid bacteria strains isolated from kefir are superior to those from other sources for improving glucuronic acid production and enhancing the antibacterial and antioxidant activities of kombucha. This study illustrates the potential of Lactobacillus casei and Lactobacillus plantarum isolated from kefir as biosupplements for enhancing the bioactivities of kombucha.

Growth of Aeromonas species on increasing concentrations of sodium chloride.

PubMed

Delamare, A P; Costa, S O; Da Silveira, M M; Echeverrigaray, S

2000-01-01

The growth of 16 strains of Aeromonas, representing 12 species of the genera, were examined at different salt levels (0-1.71 M NaCl). All the strains grew on media with 0.34 M NaCl, and nine on media with 0.68 M. Two strains, Aer. enteropelogenes and Aer. trota, were able to grow on media with 0.85 M and 1.02 M NaCl, respectively. Comparison of the growth curves of Aer. hydrophila ATCC7966 and Aer. trota ATCC 49657 on four concentrations of NaCl (0.08, 0.34, 0.68 and 1.02 M) confirm the high tolerance of Aer. trota, and indicate that high concentrations of salt increase the lag time and decrease the maximum growth rate. However, both strains were able to grow, slowly, in at least 0.68 M NaCl, a sodium chloride concentration currently used as food preservative.

[ABILITY OF STAPHYLOCOCCUS OF VARIOUS STRAINS TO CREATE BIOFILMS AND THEIR EFFECT ON HUMAN BODY CELLS].

PubMed

Kornienko, M A; Kopyltsov, V N; Shevlyagina, N V; Didenko, L V; Lyubasovskaya, L A; Priputnevich, T V; Ilina, E N

2016-01-01

The urgency of the staphylococcus research is due to its ability to cause severe infections: softtissue infections, endocarditis, sepsis, toxic shock syndrome, and food poisoning. Coagulase-positive Staphylococcus aureus is the main infection agent of intrahospital infections. This agent has many factors of pathogenicity, which are well known. Among the coagulase-negative staphylococcus (CNS) strains, S. haemolyticus and S. epidermidis are clinically important, because they cause infections in patients with weak immune system. The mechanisms of the CNS pathogenicity are insufficiently understood. The goal of this work was to evaluate the potential pathogenicity of clinical strains of CNS from their capacity to create biofilms and the character of their interaction with human body cells by the example of the HT-29 cell culture. The research was carried out in laboratory strain S. aureus ATCC 29213 and clinical strains S. haemolyticus SH39, S. epidermidis SE36-1 isolated from the neonatal autopsy materials. The visual tests of biofilm formation by each strain and testing of the impact of the strains on the cell culture HT-29 was carried out in this work. The two species of CNS form biofilms at a higher rate than S. aureus. Upon incubation for 2 h of HT-29 cells with staphylococcus strains tested in this work, adhesion of bacteria on cell surface was observed. The adhesion was most pronounced in case of S. aureus ATCC 29213 and S. haemolyticus SH39. Upon 3 h of incubation with S. aureus ATCC 29213 and S. haemolyticus SH39, destruction of cell HT-29 monolayer was observed. The incubation for 24 h with the 3 strains tested in this work caused complete destruction of cell HT-29 monolayer. The maximal toxic effect on HT-29 cells was inherent in the strain S. haemolyticus SH39. The aggregate of the results obtained in this work indicates the presence of the pathogenicity factors in the strains S. haemolyticus SH39, which require additional research.

Draft genome sequences of Streptococcus bovis strains ATCC 33317 and JB1

USDA-ARS?s Scientific Manuscript database

We report the draft genome sequences of Streptococcus bovis type strain ATTC 33317 (CVM42251) isolated from cow dung and strain JB1 (CVM42252) isolated from a cow rumen in 1977. Strains were subjected to Next Generation sequencing and the genome sizes are approximately 2 MB and 2.2 MB, respectively....

Response to Bile Salts in Clinical Strains of Acinetobacter baumannii Lacking the AdeABC Efflux Pump: Virulence Associated with Quorum Sensing

PubMed Central

López, Maria; Blasco, Lucia; Gato, Eva; Perez, Astrid; Fernández-Garcia, Laura; Martínez-Martinez, Luis; Fernández-Cuenca, Felipe; Rodríguez-Baño, Jesús; Pascual, Alvaro; Bou, German; Tomás, Maria

2017-01-01

Introduction: Acinetobacter baumannii is an opportunistic nosocomial pathogen associated with multiple infections. This pathogen usually colonizes (first stage of microbial infection) host tissues that are in contact with the external environment. As one of the sites of entry in human hosts is the gastrointestinal tract, the pathogen must be capable of tolerating bile salts. However, studies analyzing the molecular characteristics involved in the response to bile salts in clinical strains of A. baumannii are scarce. Material and Methods: Microbiological and transcriptional studies (arrays and RT-PCR) in the response to bile salts were carried out in isogenic (A. baumanni ΔadeB ATCC 17978 and A. baumannii ΔadeL ATCC 17978) and clinical strains from clone ST79/PFGE-HUI-1 which is characterized by lacking the AdeABC efflux pump and by overexpression the AdeFGH efflux pump. Results and Discussion: In presence of bile salts, in addition to the glutamate/aspartate transporter were found overexpressed in A. baumannii ΔadeB ATCC 17978, the virulence factors (surface motility, biofilm, and Type VI Secretion System) which are associated with activation of the Quorum Sensing system. Overexpression of these factors was confirmed in clinical strains of clone ST79/PFGE-HUI-1. Conclusions: This the first study about the adaptive response to bile salts investigating the molecular and microbiological characteristics in response to bile salts of an isogenic model of A. baumannii ATCC 17978 and clinical isolates of A. baumannii (clinical strains of ST79/PFGE-HUI-1) lacking the main RND efflux pump (AdeABC). Clinical isolates of A. baumannii lacking the AdeABC efflux pump (clone ST79/PFGE-HUI-1) displayed a new clinical profile (increased invasiveness) possibly associated with the response to stress conditions (such as the presence of bile salts). PMID:28536672

Reclassification of rhizosphere bacteria including strains causing corky root of lettuce and proposal of Rhizorhapis suberifaciens gen. nov., comb. nov., Sphingobium mellinum sp. nov., Sphingobium xanthum sp. nov. and Rhizorhabdus argentea gen. nov., sp. nov.

PubMed

Francis, Isolde M; Jochimsen, Kenneth N; De Vos, Paul; van Bruggen, Ariena H C

2014-04-01

The genus Rhizorhapis gen. nov. (to replace the illegitimate genus name Rhizomonas) is proposed for strains of Gram-negative bacteria causing corky root of lettuce, a widespread and important lettuce disease worldwide. Only one species of the genus Rhizomonas was described, Rhizomonas suberifaciens, which was subsequently reclassified as Sphingomonas suberifaciens based on 16S rRNA gene sequences and the presence of sphingoglycolipid in the cell envelope. However, the genus Sphingomonas is so diverse that further reclassification was deemed necessary. Twenty new Rhizorhapis gen. nov.- and Sphingomonas-like isolates were obtained from lettuce or sow thistle roots, or from soil using lettuce seedlings as bait. These and previously reported isolates were characterized in a polyphasic study including 16S rRNA gene sequencing, DNA-DNA hybridization, DNA G+C content, whole-cell fatty acid composition, morphology, substrate oxidation, temperature and pH sensitivity, and pathogenicity to lettuce. The isolates causing lettuce corky root belonged to the genera Rhizorhapis gen. nov., Sphingobium, Sphingopyxis and Rhizorhabdus gen. nov. More specifically, we propose to reclassify Rhizomonas suberifaciens as Rhizorhapis suberifaciens gen. nov., comb. nov. (type strain, CA1(T) = LMG 17323(T) = ATCC 49355(T)), and also propose the novel species Sphingobium xanthum sp. nov., Sphingobium mellinum sp. nov. and Rhizorhabdus argentea gen. nov., sp. nov. with the type strains NL9(T) ( = LMG 12560(T) = ATCC 51296(T)), WI4(T) ( = LMG 11032(T) = ATCC 51292(T)) and SP1(T) ( = LMG 12581(T) = ATCC 51289(T)), respectively. Several strains isolated from lettuce roots belonged to the genus Sphingomonas, but none of them were pathogenic.

[Sensitivity to disinfectants of Candid albicans strains isolated from the hospital environment].

PubMed

Tadeusiak, B

1998-01-01

In recent years an increase of the incidence of Candida infections caused mainly by C. albicans strains especially in high risk inpatients with neoplasms, decreased immunity, burns and after treatment with multiple antibiotics has been observed. Candida organisms are particularly dangerous for newborns being responsible for about 30% of septicaemia cases in newborns in intensive care units. Fungal infections can be endogenous in origin but exogenous infection sources occur in hospitals. The cause of the latter are errors in aseptic management and insufficiently disinfected medical instruments and equipment. The purpose of the study was a comparison of the sensitivity to disinfectants of C. albicans belonging to two laboratory strains C. albicans PZH and C. albicans ATCC 10231 used for the determination of concentrations of two disinfectants used. Besides that, this sensitivity was determined in 14 strains isolated from the patients and one from the circuit of dialysis solution supply to artificial kidney. The study was carried out by the qualitative suspension method, in which the cells in the fluid were subjected to the action of disinfectants, and by the carrier method in which the cells of the microorganisms were present on the surface of metal cylinders. By the suspension method the sensitivity was determined to chloramine T in concentrations from 5.0% to 0.001%, formalin from 10.0% to 0.25%, glutaraldehyde from 2.0% to 0.1%, Septyl from 3.5% to 0.25%. The exposure time was 5, 10, 15, 30 and 60 minutes. The tested strains differed in their sensitivity to the disinfectants used. The greatest interstrain differences were observed in the sensitivity to the disinfectants used. The greatest interstrain differences were observed in the sensitivity to chloramine T. The highest concentrations were tolerated by the strains isolated from the patients and from the artificial kidney circuit as well as by the standard strain ATCC 10231. In the 10-minute exposure time accepted by us as comparison standard these strains were 200-time less susceptible to chloramine than the standard C. albicans PZH strain. Two strain isolated from the patients were tenfold as sensitivive. The sensitivity to the remaining tested disinfectants showed less evident differences. The sensitivity of the strains from the patients to formalin was similar to that of the standard PZH strain. A similar sensitivity was found to Septyl, with the exception of the strain from the artificial kidney circuit which was sevenfold less sensitive than the PZH strain. In the case of glutaraldehyde 9 strains from the patients and the ATCC 10231 strain were two or four times less sensitive than the PZH strain. No cross-sensitivity or tolerance to the disinfectants were noted in the study. Both standard strains were similarly sensitive to formalin, but the ATCC 10231 strain was less sensitive to Septyl, glutaraldehyde and chloramine T. In the experiment by the carrier method the effect was evidenced of the surface on the action of disinfectants. This was particularly evident in the case of chloramine T. Even in sensitive strains the disinfection parameters (concentration and exposure time) were significantly higher than in the suspension method. The least sensitive strains survived the effect of 5% chloramine during 2 hours of exposure. Septyl in the working concentration 2.5% at 10-minute exposure time disinfected all carriers with the exception of that carrying the strain isolated from the artificial kidney circuit, which survived 15% Septyl exposure during 10 minutes. The disinfectant Aldesan (2% glutaraldehyde) and formalin 8% killed all fungi during 10 minutes. The study shows that the sensitivity of C. albicans strains to disinfectants varies. For the assessment of the fungicidal action of disinfectants the standard test ATCC 10231 should be used since its sensitivity was similar to that of most strains from the patients and medical equipment. (ABSTRACT TRUNCATED)

ANTIFUNGAL POTENTIAL OF PLANT SPECIES FROM BRAZILIAN CAATINGA AGAINST DERMATOPHYTES

PubMed Central

BIASI-GARBIN, Renata Perugini; DEMITTO, Fernanda de Oliveira; do AMARAL, Renata Claro Ribeiro; FERREIRA, Magda Rhayanny Assunção; SOARES, Luiz Alberto Lira; SVIDZINSKI, Terezinha Inez Estivalet; BAEZA, Lilian Cristiane; YAMADA-OGATTA, Sueli Fumie

2016-01-01

Trichophyton rubrum and Trichophyton mentagrophytes complex, or Trichophyton spp. are the main etiologic agents of dermatophytosis, whose treatment is limited by the high cost of antifungal treatments, their various side effects, and the emergence of resistance amongst these species. This study evaluated the in vitro antidermatophytic activity of 23 crude extracts from nine plant species of semiarid vegetation (caatinga) found in Brazil. The extracts were tested at concentrations ranging from 1.95 to 1,000.0 mg/mL by broth microdilution assay against the reference strains T. rubrum ATCC 28189 and T. mentagrophytesATCC 11481, and 33 clinical isolates of dermatophytes. All plants showed a fungicidal effect against both fungal species, with MIC/MFC values of the active extracts ranging from 15.6 to 250.0 µg/mL. Selected extracts of Eugenia uniflora (AcE), Libidibia ferrea (AE), and Persea americana (AcE) also exhibited a fungicidal effect against all clinical isolates of T. rubrum and T. mentagrophytes complex. This is the first report of the antifungal activity of Schinus terebinthifolius, Piptadenia colubrina, Parapiptadenia rigida, Mimosa ophthalmocentra, and Persea americana against both dermatophyte species. PMID:27007561

ANTIFUNGAL POTENTIAL OF PLANT SPECIES FROM BRAZILIAN CAATINGA AGAINST DERMATOPHYTES.

PubMed

Biasi-Garbin, Renata Perugini; Demitto, Fernanda de Oliveira; Amaral, Renata Claro Ribeiro do; Ferreira, Magda Rhayanny Assunção; Soares, Luiz Alberto Lira; Svidzinski, Terezinha Inez Estivalet; Baeza, Lilian Cristiane; Yamada-Ogatta, Sueli Fumie

2016-01-01

Trichophyton rubrum and Trichophyton mentagrophytes complex, or Trichophyton spp. are the main etiologic agents of dermatophytosis, whose treatment is limited by the high cost of antifungal treatments, their various side effects, and the emergence of resistance amongst these species. This study evaluated the in vitro antidermatophytic activity of 23 crude extracts from nine plant species of semiarid vegetation (caatinga) found in Brazil. The extracts were tested at concentrations ranging from 1.95 to 1,000.0 mg/mL by broth microdilution assay against the reference strains T. rubrum ATCC 28189 and T. mentagrophytes ATCC 11481, and 33 clinical isolates of dermatophytes. All plants showed a fungicidal effect against both fungal species, with MIC/MFC values of the active extracts ranging from 15.6 to 250.0 µg/mL. Selected extracts of Eugenia uniflora (AcE), Libidibia ferrea (AE), and Persea americana (AcE) also exhibited a fungicidal effect against all clinical isolates of T. rubrum and T. mentagrophytes complex. This is the first report of the antifungal activity of Schinus terebinthifolius, Piptadenia colubrina, Parapiptadenia rigida, Mimosa ophthalmocentra, and Persea americana against both dermatophyte species.

Differential identification of Candida species and other yeasts by analysis of (/sup 35/S)methionine-labeled polypeptide profiles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, H.D.; Choo, K.B.; Tsai, W.C.

1988-12-01

This paper describes a scheme for differential identification of Candida species and other yeasts based on autoradiographic analysis of protein profiles of (/sup 35/S)methionine-labeled cellular proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Using ATCC strains as references, protein profile analysis showed that different Candida and other yeast species produced distinctively different patterns. Good agreement in results obtained with this approach and with other conventional systems was observed. Being accurate and reproducible, this approach provides a basis for the development of an alternative method for the identification of yeasts isolated from clinical specimens.

Heterologous expression and localization of gentisate transporter Ncg12922 from Corynebacterium glutamicum ATCC 13032

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu Ying; Graduate School of Chinese Academy of Sciences, Beijing 100049; Yan Dazhong

2006-07-28

Ralstonia sp. strain U2 metabolizes naphthalene via gentisate (2,5-dihydroxybenzoate) to central metabolites, but it was found unable to utilize gentisate as growth substrate. A putative gentisate transporter encoded by ncg12922 from Corynebacterium glutamicum ATCC 13032 was functionally expressed in Ralstonia sp. strain U2, converting strain U2 to a gentisate utilizer. After ncg12922 was inserted into plasmid pGFPe with green fluorescence protein gene gfp, the expressed fusion protein Ncg12922-GFP could be visualized in the periphery of Escherichia coli cells under confocal microscope, consistent with a cytoplasmic membrane location. In contrast, GFP was ubiquitous in the cytoplasm of E. coli cells carryingmore » pGFPe only. Gentisate 1,2-dioxygenase activity was present in the cell extract from strain U2 induced with gentisate but at a much lower level (one-fifth) than that obtained with salicylate. However, it exhibited a similar level in strain U2 containing Ncg12922 induced either by salicylate or gentisate.« less

Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components

NASA Technical Reports Server (NTRS)

Reyes, A. L.; Campbell, J. E.

1978-01-01

The experiments conducted to determine the heat resistance of Bacillus megaterium ATCC 6458 at 90 and 100 C were completed. Estimates from replicate experiments at eight percent relative humidities (less than 0.001 to 100% RH) for each temperature were computed. A Bacillus cereus strain with high heat resistance was cultured and the resistance determined in phosphate buffer (D sub 121.1 = 2.16 min and z = 8.7 C). The profile of the dry heat resistance of B. megaterium is summarized and the most resistant condition to the three spores (Bacillus subtilis var. niger, ATCC 29669, and Bacillus stearothermophilus, strain 1518) is compared.

The extracellular phage-host interactions involved in the bacteriophage LL-H infection of Lactobacillus delbrueckii ssp. lactis ATCC 15808

PubMed Central

Munsch-Alatossava, Patricia; Alatossava, Tapani

2013-01-01

The complete genome sequence of Lactobacillus bacteriophage LL-H was determined in 1996. Accordingly, LL-H has been used as a model phage for the infection of dairy Lactobacillus, specifically for thermophilic Lactobacillus delbrueckii ssp. lactis host strains, such as ATCC 15808. One of the major goals of phage LL-H research consisted of the characterization of the first phage-host interactions at the level of phage adsorption and phage DNA injection steps to determine effective and practical methods to minimize the risks associated with the appearance and attack of phages in the manufacture of yogurt, and Swiss or Italian hard type cheeses, which typically use thermophilic lactic acid bacteria starter cultures containing L. delbrueckii strains among others. This mini review article summarizes the present data concerning (i) the special features, particle structure, and components of phage LL-H and (ii) the structure and properties of lipoteichoic acids (LTAs), which are the phage LL-H receptor components of L. delbrueckii ssp. lactis host strains. Moreover, a model of the first, extracellular, phage-host interactions for the infection of L. delbrueckii ssp. lactis ATCC 15808 by phage LL-H is presented and further discussed. PMID:24400001

Efficient synthesis and antimicrobial activity of some novel S-β-d-glucosides of 5-aryl-1,2,4-triazole-3-thiones derivatives.

PubMed

Ji, Dan; Lu, JunRui; Lu, BoWei; Xin, ChunWei; Mu, JiangBei; Li, JianFa; Peng, ChunYong; Bao, XiuRong

2013-04-01

A series of 3-S-β-d-glucosides-4-arylideneamino-5-aryl-1,2,4-triazoles were rationally designed and synthesized according to the principle of superposition of bioactive substructures by the combination of 1,2,4-triazole, Schiff base and glucosides. The structures of the target compounds have been characterized by (1)H NMR, (13)C NMR, IR, MS and HRMS. All the newly synthesized compounds have been evaluated for their antimicrobial activities in vitro against Staphylococcus aureus (ATCC 6538), Escherichia coli (ATCC 8099) as well as Monilia albican (ATCC 10231). The bioactive assay showed that most of the tested compounds displayed variable inhibitory effects on the growth of the Gram-positive bacterial strain (Staphylococcus aureus), Gram-negative bacterial strains (Escherichia coli) and fungal strains (Monilia albican). All the target compounds exhibited better antifungal activity than antibacterial activity. Especially, compounds 6b, 6c, 6f, 6j, 6k and 6l showed excellent activity against fungus Monilia albican with MIC values of 16 μg/mL. Copyright © 2013 Elsevier Ltd. All rights reserved.

Strain improvement of Sporolactobacillus inulinus ATCC 15538 for acid tolerance and production of D-lactic acid by genome shuffling.

PubMed

Zheng, Huijie; Gong, Jixian; Chen, Tao; Chen, Xun; Zhao, Xueming

2010-02-01

Improvement of acid tolerance and production of D-lactic acid by Sporolactobacillus inulinus ATCC 15538 was performed by using recursive protoplast fusion in a genome shuffling format. The starting population was generated by ultraviolet irradiation, diethyl sulfate mutagenesis, and pH-gradient filter and then, subjected for the recursive protoplast fusion. The concentration of lysozyme, time, and temperature for enzyme treatment were optimized by response surface methodology based on the central composite design. Based on contour plots and variance analysis, the model predicted a maximum Y (multiply protoplasts formation ratio by protoplasts regeneration ratio), 60.4%, and the corresponding above used values were 7.75 mg/ml lysozyme, 1.59 h, and 38 degrees C. A pH-5-resistant recombinant, F3-4, was obtained after three rounds of genome shuffling and its production of D-lactic acid reached 93.4 g/l in a 5 L bioreactor, which was increased by 39.8% and 119% in comparison with that of UV generated strain and the original strain S. inulinus ATCC 15538, respectively. The subculture experiments indicated that F3-4 was genetically stable.

The extracellular phage-host interactions involved in the bacteriophage LL-H infection of Lactobacillus delbrueckii ssp. lactis ATCC 15808.

PubMed

Munsch-Alatossava, Patricia; Alatossava, Tapani

2013-12-24

The complete genome sequence of Lactobacillus bacteriophage LL-H was determined in 1996. Accordingly, LL-H has been used as a model phage for the infection of dairy Lactobacillus, specifically for thermophilic Lactobacillus delbrueckii ssp. lactis host strains, such as ATCC 15808. One of the major goals of phage LL-H research consisted of the characterization of the first phage-host interactions at the level of phage adsorption and phage DNA injection steps to determine effective and practical methods to minimize the risks associated with the appearance and attack of phages in the manufacture of yogurt, and Swiss or Italian hard type cheeses, which typically use thermophilic lactic acid bacteria starter cultures containing L. delbrueckii strains among others. This mini review article summarizes the present data concerning (i) the special features, particle structure, and components of phage LL-H and (ii) the structure and properties of lipoteichoic acids (LTAs), which are the phage LL-H receptor components of L. delbrueckii ssp. lactis host strains. Moreover, a model of the first, extracellular, phage-host interactions for the infection of L. delbrueckii ssp. lactis ATCC 15808 by phage LL-H is presented and further discussed.

The impact of ethanol extract of propolis on biofilm forming by Proteus Mirabilis strains isolated from chronic wounds infections.

PubMed

Kwiecińska-Piróg, Joanna; Skowron, Krzysztof; Śniegowska, Agata; Przekwas, Jana; Balcerek, Maciej; Załuski, Daniel; Gospodarek-Komkowska, Eugenia

2018-05-04

Alcoholic propolis extracts may be used to eliminate microbes in mucous membranes and skin inflammations and in wound infections. The aim of this study was an assessment of the ethanol extract of propolis (EEP) activity against biofilm formation by P. mirabilis. Six clinical strains of P. mirabilis isolated from patients with chronic wound infection, and one reference strain of P. mirabilis ATCC 29906 were used. Biofilm was formed in 96-well plate. In order to evaluate the effect of EEP at a concentration range of 1.56-100 mg/mL on the forming and mature biofilm, P. mirabilis cells were released by sonication. In this study the effectiveness of 25-100 mg/mL of EEP on the forming P. mirabilis biofilm and concentrations of 25-50 mg/mL of EEP on formed biofilm has been demonstrated. Our results suggest the possibility of using the EEP in treatment of chronic wound infection caused by P. mirabilis.

First description of atypical furunculosis in freshwater farmed Atlantic salmon, Salmo salar L., in Chile.

PubMed

Godoy, M; Gherardelli, V; Heisinger, A; Fernández, J; Olmos, P; Ovalle, L; Ilardi, P; Avendaño-Herrera, R

2010-05-01

We report the first isolation, identification and characterization of a group of Chilean strains of atypical Aeromonas salmonicida isolated from freshwater farmed Atlantic salmon, Salmo salar. Affected fish showed superficial ulcers and pale liver with or without petechial haemorrhages. Outbreaks of the disease occurred in two farms in the south of Chile about 2200 km apart. Five strains were isolated in pure culture and identified by serological assays and immunofluorescence tests as belonging to Aeromonas salmonicida. Although the bacterial isolates were phenotypically homogeneous, minor differences with the reference strain A. salmonicida subsp. salmonicida ATCC 33658 were noted. Three specific primer sets and partial 16S rRNA gene sequencing allowed the identification of the Chilean isolates as atypical A. salmonicida, with A. salmonicida subsp. achromogenes and A. salmonicida subsp. masoucida as their closest relatives (100% sequence similarity). Molecular typing indicated that the atypical isolates belong to two genetic groups that were associated with the geographical origin.

The use of nucleosides and arginine as alternative energy sources by coagulase-negative staphylococci in view of meat fermentation.

PubMed

Janssens, M; Van der Mijnsbrugge, A; Sánchez Mainar, M; Balzarini, T; De Vuyst, L; Leroy, F

2014-05-01

The ability of coagulase-negative staphylococci (CNS) to use alternative energy sources in meat may partially explain their occurrence in fermented meats. Of 61 CNS strains tested, all metabolized adenosine and inosine in a meat simulation medium (MSM). The ability to catabolize arginine via the arginine deiminase (ADI) pathway varied between strains. All tested strains of Staphylococcus carnosus and Staphylococcus epidermidis possessed an arcA gene and showed ADI activity, whereas other species, such as Staphylococcus equorum and Staphylococcus succinus, did not. Arginine catabolic mobile elements (ACME), as in the positive control S. epidermidis ATCC 12228, were uncommon and only found in Staphylococcus xylosus 3PA6 (sausage isolate) and Staphylococcus chromogenes G222 (teat apex isolate). Monoculture experiments were performed in MSM with S. carnosus 833 and SS3-4, S. xylosus G211, and S. epidermidis ATCC 12228 and 2S7-4. At all pH values tested (5.3, 5.8, and 6.5), the strains of S. carnosus catabolized arginine faster than the strains of S. xylosus and S. epidermidis. Only at pH 6.5 could a low ADI activity be found for S. xylosus G211. Increased ADI activity occurred in the case of the ACME-positive S. epidermidis ATCC 12228, when compared to the ACME-negative S. epidermidis 2S7-4. Copyright © 2013 Elsevier Ltd. All rights reserved.

Degradation of Triphenyltin by a Fluorescent Pseudomonad

PubMed Central

Inoue, Hiroyuki; Takimura, Osamu; Fuse, Hiroyuki; Murakami, Katsuji; Kamimura, Kazuo; Yamaoka, Yukiho

2000-01-01

Triphenyltin (TPT)-degrading bacteria were screened by a simple technique using a post-column high-performance liquid chromatography using 3,3′,4′,7-tetrahydroxyflavone as a post-column reagent for determination of TPT and its metabolite, diphenyltin (DPT). An isolated strain, strain CNR15, was identified as Pseudomonas chlororaphis on the basis of its morphological and biochemical features. The incubation of strain CNR15 in a medium containing glycerol, succinate, and 130 μM TPT resulted in the rapid degradation of TPT and the accumulation of approximately 40 μM DPT as the only metabolite after 48 h. The culture supernatants of strain CNR15, grown with or without TPT, exhibited a TPT degradation activity, whereas the resting cells were not capable of degrading TPT. TPT was stoichiometrically degraded to DPT by the solid-phase extract of the culture supernatant, and benzene was detected as another degradation product. We found that the TPT degradation was catalyzed by low-molecular-mass substances (approximately 1,000 Da) in the extract, termed the TPT-degrading factor. The other fluorescent pseudomonads, P. chlororaphis ATCC 9446, Pseudomonas fluorescens ATCC 13525, and Pseudomonas aeruginosa ATCC 15692, also showed TPT degradation activity similar to strain CNR15 in the solid-phase extracts of their culture supernatants. These results suggest that the extracellular low-molecular-mass substance that is universally produced by the fluorescent pseudomonad could function as a potent catalyst to cometabolite TPT in the environment. PMID:10919812

Characterisation and bioactivity of protein-bound polysaccharides from submerged-culture fermentation of Coriolus versicolor Wr-74 and ATCC-20545 strains.

PubMed

Cui, Jian; Goh, Kelvin Kim Tha; Archer, Richard; Singh, Harjinder

2007-05-01

The protein-bound polysaccharides of Coriolus versicolor (CPS) have been reported to stimulate overall immune functions against cancers and various infectious diseases by activating specific cell functions. A New Zealand isolate (Wr-74) and a patented strain (ATCC-20545) of C. versicolor were compared in this study. The fruit bodies of both strains were grown for visual verification. Both strains were grown in submerged-culture using an airlift fermentor with milk permeate as the base medium supplemented with glucose, yeast extract and salt. Metabolic profiles of both strains obtained over 7-day fermentation showed very similar trends in terms of biomass production (8.9-10.6 mg/ml), amounts of extracellular polysaccharide (EPS) from the culture medium (1150-1132 microg/ml), and intracellular polysaccharide (IPS) from the mycelium (80-100 microg/ml). Glucose was the dominant sugar in both EPS and IPS, and the polymers each consisted of three molecular weight fractions ranging from 2 x 10(6) to 3 x 10(3 )Da. Both the EPS and IPS were able to significantly induce cytokine production (interleukin 12 and gamma interferon) in murine splenocytes in vitro. Highest levels of interleukin 12 (291 pg/ml) and gamma interferon (6,159 pg/ml) were obtained from samples containing Wr-74 IPS (0.06 microg/ml) and ATCC 20545 IPS (0.1 microg/ml), respectively. The results indicated that lower levels of EPS and IPS generally resulted in higher immune responses than did higher polymer concentrations.

Isolation and identification of the antibacterial active compound from petroleum ether extract of neem oil.

PubMed

Zhang, Yu-Qun; Xu, Jiao; Yin, Zhong-Qiong; Jia, Ren-Yong; Lu, Yang; Yang, Fan; Du, Yong-Hua; Zou, Ping; Lv, Cheng; Hu, Ting-Xiu; Liu, Shu-Liang; Shu, Gang; Yi, Geng

2010-10-01

From a petroleum ether extract of neem oil (Azadirachta indica A. Juss) the new tetrahydrofuranyl diester 1 was isolated as an anti-bacterial constituent. 1 showed significant activities against three standard bacterial strains, including Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enteritidis CMCC (B) 50041. Copyright © 2010 Elsevier B.V. All rights reserved.

Effect of X-ray treatments on salmonella enterica and spoilage bacteria on skin-on chicken breast fillets and shell eggs

USDA-ARS?s Scientific Manuscript database

The objectives of this study were to determine the efficacy of X-ray irradiation on the inactivation of a 3- strain mixture of Salmonella enterica (S. Enteritidis E190-88, S. Typhimurium ATCC 14028, and S. Montevideo ATCC 8387) using an RS 2400 X-ray system on chicken breast fillets and shell eggs a...

Porphyromonas gulae Has Virulence and Immunological Characteristics Similar to Those of the Human Periodontal Pathogen Porphyromonas gingivalis.

PubMed

Lenzo, Jason C; O'Brien-Simpson, Neil M; Orth, Rebecca K; Mitchell, Helen L; Dashper, Stuart G; Reynolds, Eric C

2016-09-01

Periodontitis is a significant problem in companion animals, and yet little is known about the disease-associated microbiota. A major virulence factor for the human periodontal pathogen Porphyromonas gingivalis is the lysyl- and arginyl-specific proteolytic activity of the gingipains. We screened several Porphyromonas species isolated from companion animals-P. asaccharolytica, P. circumdentaria, P. endodontalis, P. levii, P. gulae, P. macacae, P. catoniae, and P. salivosa-for Lys- and Arg-specific proteolytic activity and compared the epithelial and macrophage responses and induction of alveolar bone resorption of the protease active species to that of Porphyromonas gingivalis Only P. gulae exhibited Lys-and Arg-specific proteolytic activity. The genes encoding the gingipains (RgpA/B and Kgp) were identified in the P. gulae strain ATCC 51700 and all publicly available 12 draft genomes of P. gulae strains. P. gulae ATCC 51700 induced levels of alveolar bone resorption in an animal model of periodontitis similar to those in P. gingivalis W50 and exhibited a higher capacity for autoaggregation and binding to oral epithelial cells with induction of apoptosis. Macrophages (RAW 264.7) were found to phagocytose P. gulae ATCC 51700 and the fimbriated P. gingivalis ATCC 33277 at similar levels. In response to P. gulae ATCC 51700, macrophages secreted higher levels of cytokines than those induced by P. gingivalis ATCC 33277 but lower than those induced by P. gingivalis W50, except for the interleukin-6 response. Our results indicate that P. gulae exhibits virulence characteristics similar to those of the human periodontal pathogen P. gingivalis and therefore may play a key role in the development of periodontitis in companion animals. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Porphyromonas gulae Has Virulence and Immunological Characteristics Similar to Those of the Human Periodontal Pathogen Porphyromonas gingivalis

PubMed Central

Lenzo, Jason C.; O'Brien-Simpson, Neil M.; Orth, Rebecca K.; Mitchell, Helen L.; Dashper, Stuart G.

2016-01-01

Periodontitis is a significant problem in companion animals, and yet little is known about the disease-associated microbiota. A major virulence factor for the human periodontal pathogen Porphyromonas gingivalis is the lysyl- and arginyl-specific proteolytic activity of the gingipains. We screened several Porphyromonas species isolated from companion animals—P. asaccharolytica, P. circumdentaria, P. endodontalis, P. levii, P. gulae, P. macacae, P. catoniae, and P. salivosa—for Lys- and Arg-specific proteolytic activity and compared the epithelial and macrophage responses and induction of alveolar bone resorption of the protease active species to that of Porphyromonas gingivalis. Only P. gulae exhibited Lys-and Arg-specific proteolytic activity. The genes encoding the gingipains (RgpA/B and Kgp) were identified in the P. gulae strain ATCC 51700 and all publicly available 12 draft genomes of P. gulae strains. P. gulae ATCC 51700 induced levels of alveolar bone resorption in an animal model of periodontitis similar to those in P. gingivalis W50 and exhibited a higher capacity for autoaggregation and binding to oral epithelial cells with induction of apoptosis. Macrophages (RAW 264.7) were found to phagocytose P. gulae ATCC 51700 and the fimbriated P. gingivalis ATCC 33277 at similar levels. In response to P. gulae ATCC 51700, macrophages secreted higher levels of cytokines than those induced by P. gingivalis ATCC 33277 but lower than those induced by P. gingivalis W50, except for the interleukin-6 response. Our results indicate that P. gulae exhibits virulence characteristics similar to those of the human periodontal pathogen P. gingivalis and therefore may play a key role in the development of periodontitis in companion animals. PMID:27354442

Thermostaphylospora grisealba gen. nov., sp. nov., isolated from mushroom compost and transfer of Thermomonospora chromogena Zhang et al. 1998 to Thermostaphylospora chromogena comb. nov.

PubMed

Wu, Hao; Liu, Bin; Shao, Yuanyuan; Ou, Xiaoyun; Huang, Fuchang

2018-02-01

A novel thermophilic actinomycete, designated strain 3-12X T , was isolated from mushroom compost in Guangxi University, Nanning, China. The novel isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and the whole-cell sugars were glucose and ribose. The predominant menaquinones were MK-9(H4) and MK-9(H6). The polar phospholipids were diphosphatidylglycerol, hydroxy-phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, ninhydrin-positive phosphoglycolipids and glycolipids. Major fatty acids were so-C16 : 0 and C17 : 0. The G+C content of the genomic DNA was 74.6 %. The 16S rRNA gene sequence analysis showed that the closest phylogenetic neighbour of strain 3-12X T was Thermomonospora chromogena ATCC 43196 T (97.0 %), other closely related strains all belonged to the family Streptosporangiaceae and showed more than 6 % divergence. The chemotaxonomic characteristics of strain 3-12X T were significantly different from Thermomonospora chromogena ATCC 43196 T and DNA-DNA hybridization showed low relatedness (48.6-55.6 %) between them, so they should be different species. Thermomonospora chromogena was removed from the genus Thermomonospora by Zhang et al. 1998 on the basis of phylogenetic, chemotaxonomic and phenotypic evidence, but its taxonomic position remains uncertain. Based on the phenotypic and phylogenetic data, strain 3-12X T represents a novel species in a new genus in the family Streptosporangiaceae. The name Thermostaphylospora griseoalba gen. nov., sp. nov. is proposed. The type strain of Thermostaphylospora grisealba is 3-12X T (=DSM 46781 T =CGMCC 4.7160 T ). We also propose transferring Thermomonospora chromogenaZhang et al. 1998 to Thermostaphylospora chromogena comb. nov. (type strain ATCC 43196 T =JCM 6244 T ).

Antimicrobial Activity of Gallium Protoporphyrin IX against Acinetobacter baumannii Strains Displaying Different Antibiotic Resistance Phenotypes.

PubMed

Arivett, Brock A; Fiester, Steven E; Ohneck, Emily J; Penwell, William F; Kaufman, Cynthia M; Relich, Ryan F; Actis, Luis A

2015-12-01

A paucity of effective, currently available antibiotics and a lull in antibiotic development pose significant challenges for treatment of patients with multidrug-resistant (MDR) Acinetobacter baumannii infections. Thus, novel therapeutic strategies must be evaluated to meet the demands of treatment of these often life-threatening infections. Accordingly, we examined the antibiotic activity of gallium protoporphyrin IX (Ga-PPIX) against a collection of A. baumannii strains, including nonmilitary and military strains and strains representing different clonal lineages and isolates classified as susceptible or MDR. Susceptibility testing demonstrated that Ga-PPIX inhibits the growth of all tested strains when cultured in cation-adjusted Mueller-Hinton broth, with a MIC of 20 μg/ml. This concentration significantly reduced bacterial viability, while 40 μg/ml killed all cells of the A. baumannii ATCC 19606(T) and ACICU MDR isolate after 24-h incubation. Recovery of ATCC 19606(T) and ACICU strains from infected A549 human alveolar epithelial monolayers was also decreased when the medium was supplemented with Ga-PPIX, particularly at a 40-μg/ml concentration. Similarly, the coinjection of bacteria with Ga-PPIX increased the survival of Galleria mellonella larvae infected with ATCC 19606(T) or ACICU. Ga-PPIX was cytotoxic only when monolayers or larvae were exposed to concentrations 16-fold and 1,250-fold higher than those showing antibacterial activity, respectively. These results indicate that Ga-PPIX could be a viable therapeutic option for treatment of recalcitrant A. baumannii infections regardless of the resistance phenotype, clone lineage, time and site of isolation of strains causing these infections and their iron uptake phenotypes or the iron content of the media. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Antimicrobial Activity of Gallium Protoporphyrin IX against Acinetobacter baumannii Strains Displaying Different Antibiotic Resistance Phenotypes

PubMed Central

Arivett, Brock A.; Fiester, Steven E.; Ohneck, Emily J.; Penwell, William F.; Kaufman, Cynthia M.; Relich, Ryan F.

2015-01-01

A paucity of effective, currently available antibiotics and a lull in antibiotic development pose significant challenges for treatment of patients with multidrug-resistant (MDR) Acinetobacter baumannii infections. Thus, novel therapeutic strategies must be evaluated to meet the demands of treatment of these often life-threatening infections. Accordingly, we examined the antibiotic activity of gallium protoporphyrin IX (Ga-PPIX) against a collection of A. baumannii strains, including nonmilitary and military strains and strains representing different clonal lineages and isolates classified as susceptible or MDR. Susceptibility testing demonstrated that Ga-PPIX inhibits the growth of all tested strains when cultured in cation-adjusted Mueller-Hinton broth, with a MIC of 20 μg/ml. This concentration significantly reduced bacterial viability, while 40 μg/ml killed all cells of the A. baumannii ATCC 19606T and ACICU MDR isolate after 24-h incubation. Recovery of ATCC 19606T and ACICU strains from infected A549 human alveolar epithelial monolayers was also decreased when the medium was supplemented with Ga-PPIX, particularly at a 40-μg/ml concentration. Similarly, the coinjection of bacteria with Ga-PPIX increased the survival of Galleria mellonella larvae infected with ATCC 19606T or ACICU. Ga-PPIX was cytotoxic only when monolayers or larvae were exposed to concentrations 16-fold and 1,250-fold higher than those showing antibacterial activity, respectively. These results indicate that Ga-PPIX could be a viable therapeutic option for treatment of recalcitrant A. baumannii infections regardless of the resistance phenotype, clone lineage, time and site of isolation of strains causing these infections and their iron uptake phenotypes or the iron content of the media. PMID:26416873

Scheffersomyces parashehatae f.a., sp. nov., Scheffersomyces xylosifermentans f.a., sp. nov., Candida broadrunensis sp. nov. and Candida manassasensis sp. nov., novel yeasts associated with wood-ingesting insects, and their ecological and biofuel implications.

PubMed

Suh, Sung-Oui; Houseknecht, Janice L; Gujjari, Pushpa; Zhou, Jianlong J

2013-11-01

During a survey of yeasts associated with wood-ingesting insects, 69 strains in the Scheffersomyces clade and related taxa were isolated from passalid and tenebrionid beetles and the decayed wood inhabited by them. The majority of these yeasts was found to be capable of fermenting xylose, and was recognized as Scheffersomyces stipitis or its close relative Scheffersomyces illinoinensis, which are known to be associated with wood-decaying beetles and rotten wood. Yeasts in 'Scheffersomyces' ( = Candida) ergatensis and 'Scheffersomyces' ( = Candida) coipomoensis were also frequently isolated. The remaining six strains were identified as representing four novel species in the genera Scheffersomyces and Candida based on multilocus sequence analyses of nuclear rRNA genes and four protein-coding genes, as well as other taxonomic characteristics. Two xylose-fermenting species, Scheffersomyces parashehatae f.a., sp. nov. (type strain ATCC MYA-4653(T) = CBS 12535(T) = EH045(T); MycoBank MB805440) and Scheffersomyces xylosifermentans f.a., sp. nov. (type strain ATCC MYA-4859(T) = CBS 12540(T) = MY10-052(T); MycoBank MB805441), formed a clade with Scheffersomyces shehatae and related Scheffersomyces species. Interestingly, S. xylosifermentans can survive at 40 °C, which is a rare property among xylose-fermenting yeasts. Candida broadrunensis sp. nov. (type strain ATCC MYA-4650(T) = CBS 11838(T) = EH019(T); MycoBank MB805442) is a sister taxon of C. ergatensis, while Candida manassasensis sp. nov. (type strain ATCC MYA-4652(T) = CBS 12534(T) = EH030(T); MycoBank MB805443) is closely related to Candida palmioleophila in the Candida glaebosa clade. The multilocus DNA sequence comparisons in this study suggest that the genus Scheffersomyces needs to be circumscribed to the species near S. stipitis (type species) and S. shehatae that can be characterized by the ability to ferment xylose.

Isolation and characterization of a nonpigmented variant of Porphyromonas endodontalis.

PubMed

Suzuki, K; Ikeda, T; Nakamura, H; Yoshimura, F

1997-06-01

Porphyromonas endodontalis forms dark colonies on media containing blood. We isolated, from an infected root canal, a non-black-pigmented P. endodontalis variant, KSEW01, which forms beige colonies on blood agar media. To characterize this variant, we compared its properties with those of two black-pigmented P. endodontalis strains, ATCC35406 and KSE105. Strain KSEW01 had a gelatinase activity comparable to that of the pigmented strains. Cell lysates of these three strains resolved by SDS-PAGE electrophoresis showed similar protein patterns. Quantitative DNA-DNA hybridization experiments indicated high homology between the nonpigmented strain KSEW01 and the two dark-pigmented strains. From these results, we identified strain KSEW01 as a P. endodontalis nonpigmented variant. DNA restriction endonuclease analysis indicated that the variant was closely related to a pigmented strain, KSE105. In contrast to the pigmented strains, strain KSEW01 did not degrade hemoglobin and formed no vesicles when cultured in the presence of blood. The susceptibilities of these three strains to 22 antibiotics were similar except for vancomycin. The nonpigmented variant was the most resistant to vancomycin (MIC: ATCC35406, 6.25 micrograms/ml; KSE105,12.5 micrograms/ml; KSEW01, 100 micrograms/ml). Overall, a relationship may exist between the presence of black-pigmentation and outer membrane systems of P. endodontalis.

[In vitro activity of Eucalyptus smithii and Juniperus communis essential oils against bacterial biofilms and efficacy perspectives of complementary inhalation therapy in chronic and recurrent upper respiratory tract infections].

PubMed

Camporese, Alessandro

2013-06-01

Staphylococcus aureus and Pseudomonas aeruginosa have a high propensity to develop biofilms that are resistant to antimicrobial agents. Eucalyptus smithii and Juniperus communis essential oils are credited with a series of traditional therapeutical properties, including mucolytic effect. As S. aureus and P. aeruginosa biofilms are known to be important factors underlying their virulence and pathogenicity, the aim of this study was to investigate whether E. smithii and J. communis essential oils can interfere with biofilm formation as well as acting on mature biofilms. Tests of two S. aureus and P. aeruginosa clinical strains and two ATCC strains (S. aureus ATCC 25923 and P. aeruginosa ATCC 27853) showed that both E. smithii and J. communis essential oils interfere with the starting phases of biofilm production, as well as with mature biofilms. The results of this study reveal new relevant perspectives for a complementary inhalatory treatment of chronic and/or recurrent upper respiratory tract infections.

Enhancing hydrogen production of Enterobacter aerogenes by heterologous expression of hydrogenase genes originated from Synechocystis sp.

PubMed

Song, Wenlu; Cheng, Jun; Zhao, Jinfang; Zhang, Chuanxi; Zhou, Junhu; Cen, Kefa

2016-09-01

The hydrogenase genes (hoxEFUYH) of Synechocystis sp. PCC 6803 were cloned and heterologously expressed in Enterobacter aerogenes ATCC13408 for the first time in this study, and the hydrogen yield was significantly enhanced using the recombinant strain. A recombinant plasmid containing the gene in-frame with Glutathione-S-Transferase (GST) gene was transformed into E. aerogenes ATCC13408 to produce a GST-fusion protein. SDS-PAGE and western blot analysis confirm the successful expression of the hox genes. The hydrogenase activity of the recombinant strain is 237.6±9.3ml/(g-DW·h), which is 152% higher than the wild strain. The hydrogen yield of the recombinant strain is 298.3ml/g-glucose, which is 88% higher than the wild strain. During hydrogen fermentation, the recombinant strain produces more acetate and butyrate, but less ethanol. This is corresponding to the NADH metabolism in the cell due to the higher hydrogenase activity with the heterologous expression of hox genes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inhibition of attachment of oral bacteria to immortalized human gingival fibroblasts (HGF-1) by tea extracts and tea components

PubMed Central

2013-01-01

Background Tea has been suggested to promote oral health by inhibiting bacterial attachment to the oral cavity. Most studies have focused on prevention of bacterial attachment to hard surfaces such as enamel. Findings This study investigated the effect of five commercial tea (green, oolong, black, pu-erh and chrysanthemum) extracts and tea components (epigallocatechin gallate and gallic acid) on the attachment of five oral pathogens (Streptococcus mutans ATCC 25175, Streptococcus mutans ATCC 35668, Streptococcus mitis ATCC 49456, Streptococcus salivarius ATCC 13419 and Actinomyces naeslundii ATCC 51655) to the HGF-1 gingival cell line. Extracts of two of the teas (pu-erh and chrysanthemum) significantly (p < 0.05) reduced attachment of all the Streptococcus strains by up to 4 log CFU/well but effects of other teas and components were small. Conclusions Pu-erh and chrysanthemum tea may have the potential to reduce attachment of oral pathogens to gingival tissue and improve the health of oral soft tissues. PMID:23578062

Comparative study of the chemical profiling, antioxidant and antimicrobial activities of essential oils of different parts of Thymus willdenowii Boiss & Reut.

PubMed

Ouknin, Mohamed; Romane, Abderrahmane; Costa, Jean; Majidi, Lhou

2018-02-27

The analysis of Thymus willdenowii Boiss & Reut essential oils (TW EOs) shows 33 components accounting for (96.3-97.7%) of all identified. The main constituents of TW EOs were thymol (35.5-47.3%), p-cymene (13.9-23.8%), γ-terpinene (8.9-20.3%). The antioxidant assays revealed that all TW EOs tested showed strong activities, the antimicrobial effect of TW EOs has been tested against isolated clinical strains of Proteus mirabilis (ATCC 35659), Escherichia coli (ATCC 25922), Candida albicans (ATCC 10231), Bacillus cereus (ATCC 10876), and Aspergillus brasilliensis (ATCC 16404). The antimicrobial test indicates that TW EOs show an inhibition effect against all the tested bacteria with a MIC of 6.9 to 27.6 μg/mL -1 . These results proving that the essential oils extracted from Thymus willdenowii Boiss & Reut may be a new potential source of natural antimicrobial applied in pharmaceutical and food industries.

Inhibition of attachment of oral bacteria to immortalized human gingival fibroblasts (HGF-1) by tea extracts and tea components.

PubMed

Wang, Yi; Chung, Felicia F L; Lee, Sui M; Dykes, Gary A

2013-04-11

Tea has been suggested to promote oral health by inhibiting bacterial attachment to the oral cavity. Most studies have focused on prevention of bacterial attachment to hard surfaces such as enamel. This study investigated the effect of five commercial tea (green, oolong, black, pu-erh and chrysanthemum) extracts and tea components (epigallocatechin gallate and gallic acid) on the attachment of five oral pathogens (Streptococcus mutans ATCC 25175, Streptococcus mutans ATCC 35668, Streptococcus mitis ATCC 49456, Streptococcus salivarius ATCC 13419 and Actinomyces naeslundii ATCC 51655) to the HGF-1 gingival cell line. Extracts of two of the teas (pu-erh and chrysanthemum) significantly (p < 0.05) reduced attachment of all the Streptococcus strains by up to 4 log CFU/well but effects of other teas and components were small. Pu-erh and chrysanthemum tea may have the potential to reduce attachment of oral pathogens to gingival tissue and improve the health of oral soft tissues.

Bis-Indolyl Benzenoids, Hydroxypyrrolidine Derivatives and Other Constituents from Cultures of the Marine Sponge-Associated Fungus Aspergillus candidus KUFA0062

PubMed Central

Ramos, Alice A.; Inácio, Ângela; Dethoup, Tida; Lee, Michael; Sekeroglu, Nazim; Rocha, Eduardo

2018-01-01

A previously unreported bis-indolyl benzenoid, candidusin D (2e) and a new hydroxypyrrolidine alkaloid, preussin C (5b) were isolated together with fourteen previously described compounds: palmitic acid, clionasterol, ergosterol 5,8-endoperoxides, chrysophanic acid (1a), emodin (1b), six bis-indolyl benzenoids including asterriquinol D dimethyl ether (2a), petromurin C (2b), kumbicin B (2c), kumbicin A (2d), 2″-oxoasterriquinol D methyl ether (3), kumbicin D (4), the hydroxypyrrolidine alkaloid preussin (5a), (3S, 6S)-3,6-dibenzylpiperazine-2,5-dione (6) and 4-(acetylamino) benzoic acid (7), from the cultures of the marine sponge-associated fungus Aspergillus candidus KUFA 0062. Compounds 1a, 2a–e, 3, 4, 5a–b, and 6 were tested for their antibacterial activity against Gram-positive and Gram-negative reference and multidrug-resistant strains isolated from the environment. Only 5a exhibited an inhibitory effect against S. aureus ATCC 29213 and E. faecalis ATCC29212 as well as both methicillin-resistant S. aureus (MRSA) and vancomycin-resistant enterococci (VRE) strains. Both 1a and 5a also reduced significant biofilm formation in E. coli ATCC 25922. Moreover, 2b and 5a revealed a synergistic effect with oxacillin against MRSA S. aureus 66/1 while 5a exhibited a strong synergistic effect with the antibiotic colistin against E. coli 1410/1. Compound 1a, 2a–e, 3, 4, 5a–b, and 6 were also tested, together with the crude extract, for cytotoxic effect against eight cancer cell lines: HepG2, HT29, HCT116, A549, A 375, MCF-7, U-251, and T98G. Except for 1a, 2a, 2d, 4, and 6, all the compounds showed cytotoxicity against all the cancer cell lines tested. PMID:29642369

Draft Genome Sequence of Pseudomonas chlororaphis ATCC 9446, a Nonpathogenic Bacterium with Bioremediation and Industrial Potential.

PubMed

Moreno-Avitia, Fabian; Lozano, Luis; Utrilla, Jose; Bolívar, Francisco; Escalante, Adelfo

2017-06-08

Pseudomonas chlororaphis strain ATCC 9446 is a biocontrol-related organism. We report here its draft genome sequence assembled into 35 contigs consisting of 6,783,030 bp. Genome annotation predicted a total of 6,200 genes, 6,128 coding sequences, 81 pseudogenes, 58 tRNAs, 4 noncoding RNAs (ncRNAs), and 41 frameshifted genes. Copyright © 2017 Moreno-Avitia et al.

Transposon mutagenesis of probiotic Lactobacillus casei identifies asnH, an asparagine synthetase gene involved in its immune-activating capacity.

PubMed

Ito, Masahiro; Kim, Yun-Gi; Tsuji, Hirokazu; Takahashi, Takuya; Kiwaki, Mayumi; Nomoto, Koji; Danbara, Hirofumi; Okada, Nobuhiko

2014-01-01

Lactobacillus casei ATCC 27139 enhances host innate immunity, and the J1 phage-resistant mutants of this strain lose the activity. A transposon insertion mutant library of L. casei ATCC 27139 was constructed, and nine J1 phage-resistant mutants out of them were obtained. Cloning and sequencing analyses identified three independent genes that were disrupted by insertion of the transposon element: asnH, encoding asparagine synthetase, and dnaJ and dnaK, encoding the molecular chaperones DnaJ and DnaK, respectively. Using an in vivo mouse model of Listeria infection, only asnH mutant showed deficiency in their ability to enhance host innate immunity, and complementation of the mutation by introduction of the wild-type asnH in the mutant strain recovered the immuno-augmenting activity. AsnH protein exhibited asparagine synthetase activity when the lysozyme-treated cell wall extracts of L. casei ATCC 27139 was added as substrate. The asnH mutants lost the thick and rigid peptidoglycan features that are characteristic to the wild-type cells, indicating that AsnH of L. casei is involved in peptidoglycan biosynthesis. These results indicate that asnH is required for the construction of the peptidoglycan composition involved in the immune-activating capacity of L. casei ATCC 27139.

Antimicrobial effect of Dinoponera quadriceps (Hymenoptera: Formicidae) venom against Staphylococcus aureus strains.

PubMed

Lima, D B; Torres, A F C; Mello, C P; de Menezes, R R P P B; Sampaio, T L; Canuto, J A; da Silva, J J A; Freire, V N; Quinet, Y P; Havt, A; Monteiro, H S A; Nogueira, N A P; Martins, A M C

2014-08-01

Dinoponera quadriceps venom (DqV) was examined to evaluate the antibacterial activity and its bactericidal action mechanism against Staphylococcus aureus. DqV was tested against a standard strain of methicillin-sensitive Staphylococcus aureus (MSSA), Staph. aureus ATCC 6538P and two standard strains of methicillin-resistant Staphylococcus aureus (MRSA), Staph. aureus ATCC 33591 and Staph. aureus CCBH 5330. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), the rate of kill and pH sensitivity of the DqV were determined by microdilution tests. Bactericidal and inhibitory concentrations of DqV were tested to check its action on Staph. aureus membrane permeability and cell morphology. The MIC and MBC of DqV were 6·25 and 12·5 μg ml(-1) for Staph. aureus ATCC 6538P, 12·5 and 50 μg ml(-1) for Staph. aureus CCBH 5330 and 100 and 100 μg ml(-1) for Staph. aureus ATCC 33591, respectively. Complete bacterial growth inhibition was observed after 4 h of incubation with the MBC of DqV. A lowest MIC was observed in alkaline pH. Alteration in membrane permeability was observed through the increase in crystal violet uptake, genetic material release and morphology in atomic force microscopy. The results suggest antibacterial activity of DqV against Staph. aureus and that the venom acts in the cell membrane. Alteration in membrane permeability may be associated with the antimicrobial activity of hymenopteran venoms. © 2014 The Society for Applied Microbiology.

[Sequencing and analysis of the resistome of Streptomyces fradiae ATCC19609 in order to develop a test system for screening of new antimicrobial agents].

PubMed

Vatlin, A A; Bekker, O B; Lysenkova, L N; Korolev, A M; Shchekotikhin, A E; Danilenko, V N

2016-06-01

The paper provides the annotation and data on sequencing the antibiotic resistance genes in Streptomyces fradiae strain ATCC19609, highly sensitive to different antibiotics. Genome analysis revealed four groups of genes that determined the resistome of the tested strain. These included classical antibiotic resistance genes (nine aminoglycoside phosphotransferase genes, two beta-lactamase genes, and the genes of puromycin N-acetyltransferase, phosphinothricin N-acetyltransferase, and aminoglycoside acetyltransferase); the genes of ATP-dependent ABC transporters, involved in the efflux of antibiotics from the cell (MacB-2, BcrA, two-subunit MDR1); the genes of positive and negative regulation of transcription (whiB and padR families); and the genes of post-translational modification (serine-threonine protein kinases). A comparative characteristic of aminoglycoside phosphotransferase genes in S. fradiae ATCC19609, S. lividans TK24, and S. albus J1074, the causative agent of actinomycosis, is provided. The possibility of using the S. fradiae strain ATCC19609 as the test system for selection of the macrolide antibiotic oligomycin A derivatives with different levels of activity is demonstrated. Analysis of more than 20 semisynthetic oligomycin A derivatives made it possible to divide them into three groups according to the level of activity: inactive (>1 nmol/disk), 10 substances; with medium activity level (0.05–1 nmol/disk), 12 substances; and more active (0.01–0.05 nmol/disk), 2 substances. Important for the activity of semisynthetic derivatives is the change in the position of the 33rd carbon atom in the oligomycin A molecule.

Investigation of Linum flavum (L.) Hairy Root Cultures for the Production of Anticancer Aryltetralin Lignans.

PubMed

Renouard, Sullivan; Corbin, Cyrielle; Drouet, Samantha; Medvedec, Barbara; Doussot, Joël; Colas, Cyril; Maunit, Benoit; Bhambra, Avninder S; Gontier, Eric; Jullian, Nathalie; Mesnard, François; Boitel, Michèle; Abbasi, Bilal Haider; Arroo, Randolph R J; Lainé, Eric; Hano, Christophe

2018-03-26

Linum flavum hairy root lines were established from hypocotyl pieces using Agrobacterium rhizogenes strains LBA 9402 and ATCC 15834. Both strains were effective for transformation but induction of hairy root phenotype was more stable with strain ATCC 15834. Whereas similar accumulation patterns were observed in podophyllotoxin-related compounds (6-methoxy-podophyllotoxin, podophyllotoxin and deoxypodophyllotoxin), significant quantitative variations were noted between root lines. The influence of culture medium and various treatments (hormone, elicitation and precursor feeding) were evaluated. The highest accumulation was obtained in Gamborg B5 medium. Treatment with methyl jasmonate, and feeding using ferulic acid increased the accumulation of aryltetralin lignans. These results point to the use of hairy root culture lines of Linum flavum as potential sources for these valuable metabolites as an alternative, or as a complement to Podophyllum collected from wild stands.

Isolation of lymphocystis disease virus from sole, Solea senegalensis Kaup, and blackspot sea bream, Pagellus bogaraveo (Brunnich).

PubMed

Alonso, M C; Cano, I; Garcia-Rosado, E; Castro, D; Lamas, J; Barja, J L; Borrego, J J; Bergmann, S M

2005-04-01

Two viruses were isolated from cultured sole, Solea senegalensis, and wild blackspot sea bream, Pagellus bogaraveo, and preliminarily characterized as lymphocystis disease viruses (LCDVs). Viral isolates were characterized by morphological, biochemical and biophysical properties. In addition, the susceptibility of four fish cell lines was also tested. LCDV isolates developed cytopathic effects on the SAF-1 cell line at 5 and 6 days post-infection and reached titres of 10(6) TCID50 mL(-1). The antigenic and structural protein analysis of the two new LCDV isolates showed identical profiles to that obtained for LCDV strain Leetown NFH (ATCC VR-342), used as a reference viral strain, and for an LCDV isolate collected from gilt-head sea bream, Sparus aurata, cultured in southern Spain. Molecular confirmation was performed by polymerase chain reaction. Specific primers for LCDV produced a 270-bp DNA fragment, the expected size for LCDV.

Draft Genome Sequence of Vibrio mimicus Strain CAIM 602T

PubMed Central

Guardiola-Avila, Iliana; Acedo-Felix, Evelia; Yepiz-Plascencia, Gloria; Sifuentes-Romero, Itzel

2013-01-01

Vibrio mimicus is a Gram-negative bacterium associated with gastrointestinal diseases in humans around the world. We report the complete genome sequence of the Vibrio mimicus strain CAIM 602T (CDC1721-77, LMG 7896T, ATCC 33653T). PMID:23516211

Early detection of Zygosaccharomyces rouxii--spawned spoilage in apple juice by electronic nose combined with chemometrics.

PubMed

Wang, Huxuan; Hu, Zhongqiu; Long, Fangyu; Guo, Chunfeng; Yuan, Yahong; Yue, Tianli

2016-01-18

Spoilage spawned by Zygosaccharomyces rouxii can cause sensory defect in apple juice, which could hardly be perceived in the early stage and therefore would lead to the serious economic loss. Thus, it is essential to detect the contamination in early stage to avoid costly waste of products or recalls. In this work the performance of an electronic nose (e-nose) coupled with chemometric analysis was evaluated for diagnosis of the contamination in apple juice, using test panel evaluation as reference. The feasibility of using e-nose responses to predict the spoilage level of apple juice was also evaluated. Coupled with linear discriminant analysis (LDA), detection of the contamination was achieved after 12h, corresponding to the cell concentration of less than 2.0 log 10 CFU/mL, the level at which the test panelists could not yet identify the contamination, indicating that the signals of e-nose could be utilized as early indicators for the onset of contamination. Loading analysis indicated that sensors 2, 6, 7 and 8 were the most important in the detection of Z. rouxii-contaminated apple juice. Moreover, Z. rouxii counts in unknown samples could be well predicted by the established models using partial least squares (PLS) algorithm with high correlation coefficient (R) of 0.98 (Z. rouxii strain ATCC 2623 and ATCC 8383) and 0.97 (Z. rouxii strain B-WHX-12-53). Based on these results, e-nose appears to be promising for rapid analysis of the odor in apple juice during processing or on the shelf to realize the early detection of potential contamination caused by Z. rouxii strains. Copyright © 2015 Elsevier B.V. All rights reserved.

Growth inhibitory response and ultrastructural modification of oral-associated candidal reference strains (ATCC) by Piper betle L. extract

PubMed Central

Nordin, Mohd-Al-Faisal; Wan Harun, Wan Himratul-Aznita; Abdul Razak, Fathilah; Musa, Md Yusoff

2014-01-01

Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of P. betle was identified using liquid chromatography-mass spectrophotometry (LC-MS/MS). Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments: (i) in the absence of P. betle extract; and in the presence of P. betle extract at respective concentrations of (ii) 1 mg⋅mL−1; (iii) 3 mg⋅mL−1; and (iv) 6 mg⋅mL−1. The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates (µ). Scanning electron microscopy (SEM) was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the µ-values of the treated cells were significantly different than those of the untreated cells (P<0.05), indicating the fungistatic properties of the P. betle extract. The candidal population was also reduced from an average of 13.44×106 to 1.78×106 viable cell counts (CFU)⋅mL−1. SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity. PMID:24406634

Growth inhibitory response and ultrastructural modification of oral-associated candidal reference strains (ATCC) by Piper betle L. extract.

PubMed

Nordin, Mohd-Al-Faisal; Wan Harun, Wan Himratul-Aznita; Abdul Razak, Fathilah; Musa, Md Yusoff

2014-03-01

Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of P. betle was identified using liquid chromatography-mass spectrophotometry (LC-MS/MS). Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments: (i) in the absence of P. betle extract; and in the presence of P. betle extract at respective concentrations of (ii) 1 mg⋅mL(-1); (iii) 3 mg⋅mL(-1); and (iv) 6 mg⋅mL(-1). The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates (µ). Scanning electron microscopy (SEM) was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the µ-values of the treated cells were significantly different than those of the untreated cells (P<0.05), indicating the fungistatic properties of the P. betle extract. The candidal population was also reduced from an average of 13.44×10(6) to 1.78×10(6) viable cell counts (CFU)⋅mL(-1). SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity.

Comparative genomics of citric-acid-producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

PubMed Central

Andersen, Mikael R.; Salazar, Margarita P.; Schaap, Peter J.; van de Vondervoort, Peter J.I.; Culley, David; Thykaer, Jette; Frisvad, Jens C.; Nielsen, Kristian F.; Albang, Richard; Albermann, Kaj; Berka, Randy M.; Braus, Gerhard H.; Braus-Stromeyer, Susanna A.; Corrochano, Luis M.; Dai, Ziyu; van Dijck, Piet W.M.; Hofmann, Gerald; Lasure, Linda L.; Magnuson, Jon K.; Menke, Hildegard; Meijer, Martin; Meijer, Susan L.; Nielsen, Jakob B.; Nielsen, Michael L.; van Ooyen, Albert J.J.; Pel, Herman J.; Poulsen, Lars; Samson, Rob A.; Stam, Hein; Tsang, Adrian; van den Brink, Johannes M.; Atkins, Alex; Aerts, Andrea; Shapiro, Harris; Pangilinan, Jasmyn; Salamov, Asaf; Lou, Yigong; Lindquist, Erika; Lucas, Susan; Grimwood, Jane; Grigoriev, Igor V.; Kubicek, Christian P.; Martinez, Diego; van Peij, Noël N.M.E.; Roubos, Johannes A.; Nielsen, Jens; Baker, Scott E.

2011-01-01

The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compel additional exploration. We therefore undertook whole-genome sequencing of the acidogenic A. niger wild-type strain (ATCC 1015) and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence, and half the telomeric regions have been elucidated. Moreover, sequence information from ATCC 1015 was used to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 Mb of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis supported up-regulation of genes associated with biosynthesis of amino acids that are abundant in glucoamylase A, tRNA-synthases, and protein transporters in the protein producing CBS 513.88 strain. Our results and data sets from this integrative systems biology analysis resulted in a snapshot of fungal evolution and will support further optimization of cell factories based on filamentous fungi. PMID:21543515

Genome Sequence of Pseudomonas aeruginosa Strain LCT-PA220, Which Was Selected after Space Flight by Using Biolog's Powerful Carbon Source Utilization Technology.

PubMed

Xu, Guogang; Hu, Juan; Fang, Xiangqun; Zhang, Xuelin; Wang, Junfeng; Guo, Yinghua; Li, Tianzhi; Chen, Zhenghong; Dai, Wenkui; Liu, Changting

2014-03-13

To explore the changes of Pseudomonas aeruginosa in space flight, we present the draft genome sequence of P. aeruginosa strain LCT-PA220, which originated from a P. aeruginosa strain, ATCC 27853, that traveled on the Shenzhou-VIII spacecraft.

Genome Sequence of the Yeast Clavispora lusitaniae Type Strain CBS 6936.

PubMed

Durrens, Pascal; Klopp, Christophe; Biteau, Nicolas; Fitton-Ouhabi, Valérie; Dementhon, Karine; Accoceberry, Isabelle; Sherman, David J; Noël, Thierry

2017-08-03

Clavispora lusitaniae , an environmental saprophytic yeast belonging to the CTG clade of Candida , can behave occasionally as an opportunistic pathogen in humans. We report here the genome sequence of the type strain CBS 6936. Comparison with sequences of strain ATCC 42720 indicates conservation of chromosomal structure but significant nucleotide divergence. Copyright © 2017 Durrens et al.

Genome Sequence of the Yeast Clavispora lusitaniae Type Strain CBS 6936

PubMed Central

Klopp, Christophe; Biteau, Nicolas; Fitton-Ouhabi, Valérie; Dementhon, Karine; Accoceberry, Isabelle; Sherman, David J.; Noël, Thierry

2017-01-01

ABSTRACT Clavispora lusitaniae, an environmental saprophytic yeast belonging to the CTG clade of Candida, can behave occasionally as an opportunistic pathogen in humans. We report here the genome sequence of the type strain CBS 6936. Comparison with sequences of strain ATCC 42720 indicates conservation of chromosomal structure but significant nucleotide divergence. PMID:28774979

Characterization of NADP-dependent 7 beta-hydroxysteroid dehydrogenases from Peptostreptococcus productus and Eubacterium aerofaciens.

PubMed Central

Hirano, S; Masuda, N

1982-01-01

Peptostreptococcus productus strain b-52 (a human fecal isolate) and Eubacterium aerofaciens ATCC 25986 were found to contain NADP-dependent 7 beta-hydroxysteriod dehydrogenase activity. The enzyme was synthesized constitutively by both organisms, and the enzyme yields were suppressed by the addition of 0.5 mM 7 beta-hydroxy bile acid to the growth medium. Purification of the enzyme by chromatography resulted in preparations with 3.5 (P. productus b-52, on Sephadex G-200) and 1.8 (E. aerofaciens, on Bio-Gel A-1.5 M) times the activity of the crude cell extracts. A pH optimum of 9.8 and a molecular weight of approximately 53,000 were shown for the enzyme of strain b-52, and an optimum pH at 10.5 and a molecular weight of 45,000 was shown for that from strain ATCC 25986. Kinetic studies revealed that both enzyme preparations oxidized the 7 beta-hydroxy group in unconjugated and conjugated bile acids, a lower Km value being demonstrated with free bile acid than with glycine and taurine conjugates. No measureable activity against 3 alpha-, 7 alpha-, or 12 alpha-hydroxy groups was detected in either enzyme preparation. When tested with strain ATCC 25986, little 7 beta-hydroxy-steroid dehydrogenase activity was detected in cells grown in the presence of glucose in excess. The enzyme from strain b-52 was found to be heat labile (90% inactivation at 50 degrees C for 3 min) and highly sensitive to sulfhydryl inhibitors. PMID:6954878

Effect of Low Shear Modeled Microgravity (LSMMG) on the Probiotic Lactobacillus Acidophilus ATCC 4356

NASA Technical Reports Server (NTRS)

Stahl, S.; Voorhies, A.; Lorenzi, H.; Castro-Wallace, S.; Douglas, G.

2016-01-01

The introduction of generally recognized as safe (GRAS) probiotic microbes into the spaceflight food system has the potential for use as a safe, non-invasive, daily countermeasure to crew microbiome and immune dysregulation. However, the microgravity effects on the stress tolerances and genetic expression of probiotic bacteria must be determined to confirm translation of strain benefits and to identify potential for optimization of growth, survival, and strain selection for spaceflight. The work presented here demonstrates the translation of characteristics of a GRAS probiotic bacteria to a microgravity analog environment. Lactobacillus acidophilus ATCC 4356 was grown in the low shear modeled microgravity (LSMMG) orientation and the control orientation in the rotating wall vessel (RWV) to determine the effect of LSMMG on the growth, survival through stress challenge, and gene expression of the strain. No differences were observed between the LSMMG and control grown L. acidophilus, suggesting that the strain will behave similarly in spaceflight and may be expected to confer Earth-based benefits.

Reclassification of Flexibacter tractuosus (Lewin 1969) Leadbetter 1974 and 'Microscilla sericea' Lewin 1969 in the genus Marivirga gen. nov. as Marivirga tractuosa comb. nov. and Marivirga sericea nom. rev., comb. nov.

PubMed

Nedashkovskaya, Olga I; Vancanneyt, Marc; Kim, Seung Bum; Bae, Kyung Sook

2010-08-01

The taxonomic position of the misclassified strains [Flexibacter] tractuosus KCTC 2958T and '[Microscilla] sericea' LMG 13021 was studied using a polyphasic approach. The two strains shared 99.1% 16S rRNA gene sequence similarity and 28% DNA-DNA relatedness. On the basis of the phylogenetic evidence supported by genotypic and phenotypic data [Flexibacter] tractuosus KCTC 2958T and '[Microscilla] sericea' LMG 13021 are classified as two distinct species in a novel genus, Marivirga, in the family 'Flammeovirgaceae', as Marivirga tractuosa comb. nov. and Marivirga sericea nom. rev., comb. nov., with strains KCTC 2958T (=ATCC 23168T =CIP 106410T =DSM 4126T =NBRC 15989T =NCIMB 1408T =VKM B-1430T) and LMG 13021T (=ATCC 23182T =NBRC 15983T =NCIMB 1403T), respectively, as the type strains. The type species is Marivirga tractuosa.

Purification, properties and immunological relationship of L (+)-lactate dehydrogenase from Lactobacillus casei.

PubMed

Gordon, G L; Doelle, H W

1976-08-16

The fructose-1,6-bisphosphate-activated L-lactate dehydrogenase (EC 1.1.1.27) from Lactobacillus casei ATCC 393 has been purified to homogenity by including affinity chromatography (cibacronblue-Sephadex-G-200) and preparative polyacrylamide gel electrophoresis into the purification procedures. The enzyme has an Mr of 132000-135000 with a subunit Mr of 34000. The pH optimum was found to be 5.4 insodium acetate buffer. Tris/maleate and citrate/phosphate buffers inhibited enzyme activity at this pH. The enzyme was completely inactivated by a temperature increase from 60 degrees C to 70 degrees C. Pyruvate saturation curves were sigmoidal in the absence of fructose 1,6-bisphosphate. In the presence of 20 muM fructose 1,6-bisphosphate a Km of 1.0 mM for pyruvate was obtained, whereas fructose 1,6-bisphosphate had no effect on the Km of 0.01 mM for NADH. The use of pyruvate analogues revealed two types of pyruvate binding sites, a catalytic and an effector site. The enzyme from L. casei appears to be subject to strict metabolic control, since ADP, ATP, dihydroxyacetone phosphate and 6-phosphogluconate are strong inhibitors. Immunodiffusion experiments with a rabbit antiserum to L. casei lactate dehydrogenase revealed that L. casei ATCC 393 L (+)-lactate dehydrogenase is probably not immunologically related to group D and group N streptococci. Of 24 lactic acid bacterial strains tested only 5 strains did cross-react: L. casei ATCC 393 = L. casei var. rhamnosus ATCC 7469 - L. casei var. alactosus NCDO 680 greater than L. casei UQM 95 greater than L. plantarum ATCC 14917.

Increased resistance of contact lens related bacterial biofilms to antimicrobial activity of soft contact lens care solutions

PubMed Central

Szczotka-Flynn, Loretta B.; Imamura, Yoshifumi; Chandra, Jyotsna; Yu, Changping; Mukherjee, Pranab K.; Pearlman, Eric; Ghannoum, Mahmoud A.

2014-01-01

PURPOSE To determine if clinical and reference strains of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus form biofilms on silicone hydrogel contact lenses, and ascertain antimicrobial activities of contact lens care solutions. METHODS Clinical and American Type Culture Collection (ATCC) reference strains of Pseudomonas aeruginosa, Serratia marcescens, and Staphylococcus aureus were incubated with lotrafilcon A lenses under conditions that facilitate biofilm formation. Biofilms were quantified by quantitative culturing (colony forming units, CFUs), and gross morphology and architecture were evaluated using scanning electron microscopy (SEM) and confocal microscopy. Susceptibilities of the planktonic and biofilm growth phases of the bacteria to five common multipurpose contact lens care solutions and one hydrogen peroxide care solution were assessed. RESULTS P. aeruginosa, S. marcescens, and S. aureus reference and clinical strains formed biofilms on lotrafilcon A silicone hydrogel contact lenses, as dense networks of cells arranged in multiple layers with visible extracellular matrix. The biofilms were resistant to commonly used biguanide preserved multipurpose care solutions. P. aeruginosa and S. aureus biofilms were susceptible to a hydrogen peroxide and a polyquaternium preserved care solution, whereas S. marcescens biofilm was resistant to a polyquaternium preserved care solution but susceptible to hydrogen peroxide disinfection. In contrast, the planktonic forms were always susceptible. CONCLUSIONS P. aeruginosa, S. marcescens, and S. aureus form biofilms on lotrafilcon A contact lenses, which in contrast to planktonic cells, are resistant to the antimicrobial activity of several soft contact lens care products. PMID:19654521

Complete genome sequence of Streptomyces venezuelae ATCC 15439, a promising cell factory for production of secondary metabolites.

PubMed

Song, Ju Yeon; Yoo, Young Ji; Lim, Si-Kyu; Cha, Sun Ho; Kim, Ji-Eun; Roe, Jung-Hye; Kim, Jihyun F; Yoon, Yeo Joon

2016-02-10

Streptomyces venezuelae ATCC 15439, which produces 12- and 14-membered ring macrolide antibiotics, is a platform strain for heterologous expression of secondary metabolites. Its 9.05-Mb genome sequence revealed an abundance of genes involved in the biosynthesis of secondary metabolites and their precursors, which should be useful for the production of bioactive compounds. Copyright © 2015 Elsevier B.V. All rights reserved.

A Reverse-phase Protein Microarray-based Screen Identifies Host Signaling Dynamics upon Burkholderia spp. Infection

DTIC Science & Technology

2015-07-27

University, Manassas, VA, USA, 4 PerkinElmer, Inc., Waltham, MA, USA Burkholderia is a diverse genus of gram-negative bacteria that causes high...Burkholderia spp. infections. Materials and Methods Bacterial Strains Bm ATCC 23344, NCTC 10247, NCTC 10229, NCTC 3708, NCTC 3709, 2002721278 (Burtnick...macrophage cell line RAW264.7 was obtained from ATCC (Manassas, VA). Cells were cultured in DMEM (Life Technologies) supplemented with 10% fetal

Yeasts associated with the curculionid beetle Xyloterinus politus: Candida xyloterini sp. nov., Candida palmyrensis sp. nov. and three common ambrosia yeasts.

PubMed

Suh, Sung-Oui; Zhou, Jianlong

2010-07-01

Seven yeast strains were isolated from the body surface and galleries of Xyloterinus politus, the ambrosia beetle that attacks black oak trees. Based on rDNA sequence comparisons and other taxonomic characteristics, five of the strains were identified as members of the species Saccharomycopsis microspora, Wickerhamomyces hampshirensis and Candida mycetangii, which have been reported previously as being associated with insects. The remaining two yeast strains were proposed as representatives of two novel species, Candida xyloterini sp. nov. (type strain ATCC 62898(T)=CBS 11547(T)) and Candida palmyrensis sp. nov. (type strain ATCC 62899(T)=CBS 11546(T)). C. xyloterini sp. nov. is a close sister taxon to Ogataea dorogensis and assimilates methanol as a sole carbon source but lacks ascospores. On the other hand, C. palmyrensis sp. nov. is phylogenetically distinct from any other ambrosia yeast reported so far. The species was placed near Candida sophiae-reginae and Candida beechii based on DNA sequence analyses, but neither of these were close sister taxa to C. palmyrensis sp. nov.

Genomic and Phylogenetic Characterization of Luminous Bacteria Symbiotic with the Deep-Sea Fish Chlorophthalmus albatrossis (Aulopiformes: Chlorophthalmidae)

PubMed Central

Dunlap, Paul V.; Ast, Jennifer C.

2005-01-01

Bacteria forming light-organ symbiosis with deep-sea chlorophthalmid fishes (Aulopiformes: Chlorophthalmidae) are considered to belong to the species Photobacterium phosphoreum. The identification of these bacteria as P. phosphoreum, however, was based exclusively on phenotypic traits, which may not discriminate between phenetically similar but evolutionarily distinct luminous bacteria. Therefore, to test the species identification of chlorophthalmid symbionts, we carried out a genomotypic (repetitive element palindromic PCR genomic profiling) and phylogenetic analysis on strains isolated from the perirectal light organ of Chlorophthalmus albatrossis. Sequence analysis of the 16S rRNA gene of 10 strains from 5 fish specimens placed these bacteria in a cluster related to but phylogenetically distinct from the type strain of P. phosphoreum, ATCC 11040T, and the type strain of Photobacterium iliopiscarium, ATCC 51760T. Analysis of gyrB resolved the C. albatrossis strains as a strongly supported clade distinct from P. phosphoreum and P. iliopiscarium. Genomic profiling of 109 strains from the 5 C. albatrossis specimens revealed a high level of similarity among strains but allowed identification of genomotypically different types from each fish. Representatives of each type were then analyzed phylogenetically, using sequence of the luxABFE genes. As with gyrB, analysis of luxABFE resolved the C. albatrossis strains as a robustly supported clade distinct from P. phosphoreum. Furthermore, other strains of luminous bacteria reported as P. phosphoreum, i.e., NCIMB 844, from the skin of Merluccius capensis (Merlucciidae), NZ-11D, from the light organ of Nezumia aequalis (Macrouridae), and pjapo.1.1, from the light organ of Physiculus japonicus (Moridae), grouped phylogenetically by gyrB and luxABFE with the C. albatrossis strains, not with ATCC 11040T. These results demonstrate that luminous bacteria symbiotic with C. albatrossis, together with certain other strains of luminous bacteria, form a clade, designated the kishitanii clade, that is related to but evolutionarily distinct from P. phosphoreum. Members of the kishitanii clade may constitute the major or sole bioluminescent symbiont of several families of deep-sea luminous fishes. PMID:15691950

Genomic and phylogenetic characterization of luminous bacteria symbiotic with the deep-sea fish Chlorophthalmus albatrossis (Aulopiformes: Chlorophthalmidae).

PubMed

Dunlap, Paul V; Ast, Jennifer C

2005-02-01

Bacteria forming light-organ symbiosis with deep-sea chlorophthalmid fishes (Aulopiformes: Chlorophthalmidae) are considered to belong to the species Photobacterium phosphoreum. The identification of these bacteria as P. phosphoreum, however, was based exclusively on phenotypic traits, which may not discriminate between phenetically similar but evolutionarily distinct luminous bacteria. Therefore, to test the species identification of chlorophthalmid symbionts, we carried out a genomotypic (repetitive element palindromic PCR genomic profiling) and phylogenetic analysis on strains isolated from the perirectal light organ of Chlorophthalmus albatrossis. Sequence analysis of the 16S rRNA gene of 10 strains from 5 fish specimens placed these bacteria in a cluster related to but phylogenetically distinct from the type strain of P. phosphoreum, ATCC 11040(T), and the type strain of Photobacterium iliopiscarium, ATCC 51760(T). Analysis of gyrB resolved the C. albatrossis strains as a strongly supported clade distinct from P. phosphoreum and P. iliopiscarium. Genomic profiling of 109 strains from the 5 C. albatrossis specimens revealed a high level of similarity among strains but allowed identification of genomotypically different types from each fish. Representatives of each type were then analyzed phylogenetically, using sequence of the luxABFE genes. As with gyrB, analysis of luxABFE resolved the C. albatrossis strains as a robustly supported clade distinct from P. phosphoreum. Furthermore, other strains of luminous bacteria reported as P. phosphoreum, i.e., NCIMB 844, from the skin of Merluccius capensis (Merlucciidae), NZ-11D, from the light organ of Nezumia aequalis (Macrouridae), and pjapo.1.1, from the light organ of Physiculus japonicus (Moridae), grouped phylogenetically by gyrB and luxABFE with the C. albatrossis strains, not with ATCC 11040(T). These results demonstrate that luminous bacteria symbiotic with C. albatrossis, together with certain other strains of luminous bacteria, form a clade, designated the kishitanii clade, that is related to but evolutionarily distinct from P. phosphoreum. Members of the kishitanii clade may constitute the major or sole bioluminescent symbiont of several families of deep-sea luminous fishes.

Comparative genomics of citric-acid producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grigoriev, Igor V.; Baker, Scott E.; Andersen, Mikael R.

2011-04-28

The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compels additional exploration. We therefore undertook whole genome sequencing of the acidogenic A. niger wild type strain (ATCC 1015), and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence and half the telomeric regionsmore » have been elucidated. Moreover, sequence information from ATCC 1015 was utilized to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 megabase of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis revealed up-regulation of the electron transport chain, specifically the alternative oxidative pathway in ATCC 1015, while CBS 513.88 showed significant up-regulation of genes relevant to glucoamylase A production, such as tRNA-synthases and protein transporters. Our results and datasets from this integrative systems biology analysis resulted in a snapshot of fungal evolution and will support further optimization of cell factories based on filamentous fungi.[Supplemental materials (10 figures, three text documents and 16 tables) have been made available. The whole genome sequence for A. niger ATCC 1015 is available from NBCI under acc. no ACJE00000000. The up-dated sequence for A. niger CBS 513.88 is available from EMBL under acc. no AM269948-AM270415. The sequence data from the phylogeny study has been submitted to NCBI (GU296686-296739). Microarray data from this study is submitted to GEO as series GSE10983. Accession for reviewers is possible through: http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi token GSE10983] The dsmM_ANIGERa_coll511030F library and platform information is deposited at GEO under number GPL6758« less

Influence of hyaluronic acid on bacterial and fungal species, including clinically relevant opportunistic pathogens.

PubMed

Ardizzoni, Andrea; Neglia, Rachele G; Baschieri, Maria C; Cermelli, Claudio; Caratozzolo, Manuela; Righi, Elena; Palmieri, Beniamino; Blasi, Elisabetta

2011-10-01

Hyaluronic acid (HA) has several clinical applications (aesthetic surgery, dermatology, orthopaedics and ophtalmology). Following recent evidence, suggesting antimicrobial and antiviral properties for HA, we investigated its effects on 15 ATCC strains, representative of clinically relevant bacterial and fungal species. The in vitro system employed allowed to assess optical density of broth cultures as a measure of microbial load in a time-dependent manner. The results showed that different microbial species and, sometimes, different strains belonging to the same species, are differently affected by HA. In particular, staphylococci, enterococci, Streptococcus mutans, two Escherichia coli strains, Pseudomonas aeruginosa, Candida glabrata and C. parapsilosis displayed a HA dose-dependent growth inhibition; no HA effects were detected in E. coli ATCC 13768 and C. albicans; S. sanguinis was favoured by the highest HA dose. Therefore, the influence of HA on bacteria and fungi warrants further studies aimed at better establishing its relevance in clinical applications.

Comparative study of Gram-negative bacteria response to solar photocatalytic inactivation.

PubMed

Achouri, Faouzi; BenSaid, Myriam; Bousselmi, Latifa; Corbel, Serge; Schneider, Raphaël; Ghrabi, Ahmed

2018-06-03

Solar photocatalytic inactivation of Gram-negative bacteria with immobilized TiO 2 -P25 in a fixed-bed reactor was modeled with simplified kinetic equations. The kinetic parameters are the following: the photocatalytic inactivation coefficient (k d,QUV ), the initial bacterial reduction rate (A) in the contact with the disinfecting agent, and the threshold level of damage (n) were determined to report the effect of Q UV /TiO 2 -P25 on bacterial cultivability and viability and to compare the response of bacterial strains to photocatalytic treatment. In addition, the integration of the reactivation coefficient (C r ) in the photocatalytic inactivation equation allowed evaluating the ability of bacterial reactivation after photocatalytic stress. Results showed different responses of the bacteria strains to photocatalytic stress and the ability of certain bacterial strains such as Escherichia coli ATCC25922 and Pseudomonas aeruginosa ATCC4114 to resuscitate after photocatalytic treatment.

Two squalene synthase inhibitors, E5700 and ER-119884, interfere with cellular proliferation and induce ultrastructural and lipid profile alterations in a Candida tropicalis strain resistant to fluconazole, itraconazole, and amphotericin B.

PubMed

Ishida, Kelly; Visbal, Gonzalo; Rodrigues, Juliany Cola Fernandes; Urbina, Julio A; de Souza, Wanderley; Rozental, Sonia

2011-08-01

Three quinuclidine-based squalene synthase (SQS) inhibitors (BPQ-OH, E5700, and ER-119884) were evaluated against five Candida tropicalis strains with different susceptibility profiles to fluconazole (FLC), itraconazole (ITC), terbinafine (TRB), and amphotericin B (AMB). Although the quinuclidine derivatives were inactive against most C. tropicalis strains tested at concentrations up to 16 μg/ml, E5700 and ER-119884 showed antifungal activity against C. tropicalis ATCC 28707, a strain resistant to FLC, ITC, and AMB, with IC(50) and IC(90) values (i.e., the minimum inhibitory concentrations of the drugs determined as the lowest drug concentrations leading to a 50 and 90% of reduction in turbidity at 492 nm, respectively, after 48 h of incubation) of 1 and 4 μg/ml, respectively. Analysis of free sterols showed that non-treated C. tropicalis ATCC 28707 cells contained only 14-methylated sterols and that treatment with E5700 or ER-119884 led to a marked reduction of squalene content and the complete disappearance of the endogenous sterols. The fatty acid and phospholipid profiles in C. tropicalis ATCC 28707 cells grown in the presence of E5700 and ER-119884 were also markedly altered, with a large increase in the content of linolenic acid (C18:3), associated with a reduction in the content of linoleic (C18:2) and oleic (C18:1) acids. Treatment of C. tropicalis ATCC 28707 with E5700 or ER-119884 IC(50) values induced several ultrastructural alterations, including a marked increase in the thickness of the cell wall and the appearance of a large number of electron-dense vacuoles. In conclusion, our results indicated that E5700 and ER-119884 inhibited the growth and altered the lipid prolife and the ultrastructure of a multiple drug-resistant C. tropicalis strain. Therefore, such compounds could act as leads for the development of new treatment options against multidrug resistant Candida species.

The CsgA and Lpp proteins affect HEp-2 cell invasion, motility, and biofilm formation in a strain of Escherichia coli O157:H7

USDA-ARS?s Scientific Manuscript database

In Escherichia coli O157:H7 strain ATCC 43895, a guanine to thymine transversion in the csgD promoter created strain 43895OR. Strain 43895OR produces an abundant extracellular matrix rich in curli fibers, forms biofilm on solid surfaces, invades cultured epithelial cells, and is more virulent in mic...

The Influence of Tea Tree Oil (Melaleuca alternifolia) on Fluconazole Activity against Fluconazole-Resistant Candida albicans Strains

PubMed Central

Garbusińska, Aleksandra; Kowalska, Magdalena; Król, Wojciech

2015-01-01

The aim of this study was to evaluate the activity of fluconazole against 32 clinical strains of fluconazole-resistant Candida albicans, and C. albicans ATCC 10231 reference strain, after their exposure to sublethal concentrations of tea tree oil (TTO) or its main bioactive component terpinen-4-ol. For all tested fluconazole-resistant C. albicans strains TTO and terpinen-4-ol minimal inhibitory concentrations (MICs) were low, ranging from 0.06% to 0.5%. The 24-hour exposure of fluconazole-resistant C. albicans strains to fluconazole with sublethal dose of TTO enhanced fluconazole activity against these strains. Overall, 62.5% of isolates were classified as susceptible, 25.0% exhibited intermediate susceptibility, and 12.5% were resistant. For all of the tested clinical strains the fluconazole MIC decreased from an average of 244.0 μg/mL to an average of 38.46 μg/mL, and the fluconazole minimal fungicidal concentrations (MFC) decreased from an average of 254.67 μg/mL to an average of 66.62 μg/mL. Terpinen-4-ol was found to be more active than TTO, and strongly enhanced fluconazole activity against fluconazole-resistant C. albicans strains. The results of this study demonstrate that combining natural substances such as TTO and conventional drug such as fluconazole, may help treat difficult yeast infections. PMID:25722982

[Evaluation of common commercial systems for the identification of yeast isolates in microbiology laboratories: a multicenter study].

PubMed

Karabıçak, Nilgün; Uludağ Altun, Hatice; Karatuna, Onur; Hazırolan, Gülşen; Aksu, Neriman; Adiloğlu, Ali; Akyar, Işın

2015-04-01

Accurate and rapid identification of yeast isolates have become important in recent years for not only antifungal susceptibility testing due to the species-specific clinical resistance breakpoints but also early initiation of appropriate antifungal therapy. In clinical microbiology laboratories species identification of yeasts is often performed with several commercial systems based on biochemical properties and rarely according to the physiological and morphological characteristics. The aim of this study was to compare the two common commercial systems, VITEK 2 YST ID Card (Vitek; bioMérieux, France) and API 20C AUX (API; bioMérieux, France) with conventional mycological methods. A total of 473 clinical yeast strains isolated from clinical specimens in different university and training/research hospitals and identified by Vitek system were included in the study. The isolates were re-identified with API and conventional methods including morphological identification in the Mycology Reference Laboratory of the Public Health Institute of Turkey. Candida dubliniensis MYA 583, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida albicans ATCC 10231 and Cryptococcus neoformans ATCC 32268 were used as quality control strains and those standard strains were studied consecutively 10 days with both of the methods. The results of identification by Vitek and API were compared with the results of conventional methods for those 473 yeast isolates [6 genus (Candida, Cryptococcus, Blastoshizomyces, Rhodotorula, Saccharomyces, Trichosporon), 17 species (5 common and 12 rarely isolated)]. The performances of the systems were better (Vitek: 95%; API: 96%) for the commonly detected species (C.albicans, C.parapsilosis, C.glabrata, C.tropicalis and C.krusei) than those for rarely detected species (Vitek: 78.4%; API: 71.6%) (p= 0.155). Misidentification or unidentification were mostly detected for C.parapsilosis (Vitek: 6/87; API: 7/87) and C.glabrata (Vitek: 9/104; API: 3/104) by both of the systems. For rarely detected yeast isolates, misidentification or unidentification were most frequently observed in species of C.pelliculosa (Vitek: 3/11; API: 6/11) and C.dubliniensis (API and Vitek: 2/5) isolates. Candida guilliermondii (API: 2/5) isolates had lower rate of identification with API compared to other species. Blastoschizomyces capitatus and Saccharomyces cerevisiae isolates could not be identified by both of the systems. As a result, the accurate diagnosis of Vitek and API systems were similar in terms of consistency (86.3%). Two systems performed well in correct identification of common clinical yeast species (at least 95%), while the identification of rare species was more challenging indicating that they require further morphological and physiological testing. The addition of morphological identification to commercial systems will be useful for accurate diagnosis and treatment of mixed infections.

Feasibility of biohydrogen production from industrial wastes using defined microbial co-culture.

PubMed

Chen, Peng; Wang, Yuxia; Yan, Lei; Wang, Yiqing; Li, Suyue; Yan, Xiaojuan; Wang, Ningbo; Liang, Ning; Li, Hongyu

2015-05-06

The development of clean or novel alternative energy has become a global trend that will shape the future of energy. In the present study, 3 microbial strains with different oxygen requirements, including Clostridium acetobutylicum ATCC 824, Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D, were used to construct a hydrogen production system that was composed of a mixed aerobic-facultative anaerobic-anaerobic consortium. The effects of metal ions, organic acids and carbohydrate substrates on this system were analyzed and compared using electrochemical and kinetic assays. It was then tested using small-scale experiments to evaluate its ability to convert starch in 5 L of organic wastewater into hydrogen. For the one-step biohydrogen production experiment, H1 medium (nutrient broth and potato dextrose broth) was mixed directly with GAM broth to generate H2 medium (H1 medium and GAM broth). Finally, Clostridium acetobutylicum ATCC 824, Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D of three species microbial co-culture to produce hydrogen under anaerobic conditions. For the two-step biohydrogen production experiment, the H1 medium, after cultured the microbial strains Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D, was centrifuged to remove the microbial cells and then mixed with GAM broth (H2 medium). Afterward, the bacterial strain Clostridium acetobutylicum ATCC 824 was inoculated into the H2 medium to produce hydrogen by anaerobic fermentation. The experimental results demonstrated that the optimum conditions for the small-scale fermentative hydrogen production system were at pH 7.0, 35°C, a mixed medium, including H1 medium and H2 medium with 0.50 mol/L ferrous chloride, 0.50 mol/L magnesium sulfate, 0.50 mol/L potassium chloride, 1% w/v citric acid, 5% w/v fructose and 5% w/v glucose. The overall hydrogen production efficiency in the shake flask fermentation group was 33.7 mL/h(-1).L(-1), and those the two-step and the one-step processes of the small-scale fermentative hydrogen production system were 41.2 mL/h(-1).L(-1) and 35.1 mL/h(-1).L(-1), respectively. Therefore, the results indicate that the hydrogen production efficiency of the two-step process is higher than that of the one-step process.

Genetic characterization of Streptococcus phocae strains isolated from Atlantic salmon, Salmo salar L., in Chile.

PubMed

Valdés, I; Jaureguiberry, B; Romalde, J L; Toranzo, A E; Magariños, B; Avendaño-Herrera, R

2009-04-01

Streptococcus phocae is a beta-haemolytic bacterium frequently involved in disease outbreaks in seals causing pneumonia or respiratory infection. Since 1999, this pathogen has been isolated from diseased Atlantic salmon, Salmo salar, causing serious economic losses in the salmon industry in Chile. In this study, we used different molecular typing methods, such as pulsed-field gel electrophoresis (PFGE), randomly amplified polymorphic DNA (RAPD), enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR), repetitive extragenic palindromic PCR (REP-PCR) and restriction of 16S-23S rDNA intergenic spacer regions to evaluate the genetic diversity in S. phocae. Thirty-four strains isolated in different years were analysed. The S. phocae type strain ATCC 51973(T) was included for comparative purposes. The results demonstrated genetic homogeneity within the S. phocae strains isolated in Chile over several years, suggesting the existence of clonal relationships among S. phocae isolated from Atlantic salmon. The type strain ATCC 51973(T) presented a different genetic pattern with the PFGE, RAPD, ERIC-PCR and REP-PCR methods. However, the fingerprint patterns of two seal isolates were distinct from those of the type strain.

UV Tolerance of Spoilage Microorganisms and Acid-Shocked and Acid-Adapted Escherichia coli in Apple Juice Treated with a Commercial UV Juice-Processing Unit.

PubMed

Usaga, Jessie; Padilla-Zakour, Olga I; Worobo, Randy W

2016-02-01

The enhanced thermal tolerance and survival responses of Escherichia coli O157:H7 in acid and acidified foods is a major safety concern for the production of low-pH products, including beverages. Little is known about this phenomenon when using UV light treatments. This study was conducted to evaluate the effects of strain (E. coli O157:H7 strains C7927, ATCC 35150, ATCC 43895, and ATCC 43889 and E. coli ATCC 25922) and physiological state (control-unadapted, acid adapted, and acid shocked) on the UV tolerance of E. coli in apple juice treated under conditions stipulated in current U.S. Food and Drug Administration regulations. A greater than 5-log reduction of E. coli was obtained under all tested conditions. A significant effect of strain (P < 0.05) was observed, but the physiological state did not influence pathogen inactivation (P ≥ 0.05). The UV sensitivity of three spoilage microorganisms (Aspergillus niger, Penicillium commune, and Alicyclobacillus acidoterrestris) was also determined at UV doses of 0 to 98 mJ/cm(2). Alicyclobacillus was the most UV sensitive, followed by Penicillium and Aspergillus. Because of the nonsignificant differences in UV sensitivity of E. coli in different physiological states, the use of an unadapted inoculum would be adequate to conduct challenge studies with the commercial UV unit used in this study at a UV dose of 14 mJ/cm(2). The high UV tolerance of spoilage microorganisms supports the need to use a hurdle approach (e.g., coupling of refrigeration, preservatives, and/or other technologies) to extend the shelf life of UV-treated beverages.

Lovastatin Production by Aspergillus terreus Using Agro-Biomass as Substrate in Solid State Fermentation

PubMed Central

Faseleh Jahromi, Mohammad; Liang, Juan Boo; Ho, Yin Wan; Mohamad, Rosfarizan; Goh, Yong Meng; Shokryazdan, Parisa

2012-01-01

Ability of two strains of Aspergillus terreus (ATCC 74135 and ATCC 20542) for production of lovastatin in solid state fermentation (SSF) using rice straw (RS) and oil palm frond (OPF) was investigated. Results showed that RS is a better substrate for production of lovastatin in SSF. Maximum production of lovastatin has been obtained using A. terreus ATCC 74135 and RS as substrate without additional nitrogen source (157.07 mg/kg dry matter (DM)). Although additional nitrogen source has no benefit effect on enhancing the lovastatin production using RS substrate, it improved the lovastatin production using OPF with maximum production of 70.17 and 63.76 mg/kg DM for A. terreus ATCC 20542 and A. terreus ATCC 74135, respectively (soybean meal as nitrogen source). Incubation temperature, moisture content, and particle size had shown significant effect on lovastatin production (P < 0.01) and inoculums size and pH had no significant effect on lovastatin production (P > 0.05). Results also have shown that pH 6, 25°C incubation temperature, 1.4 to 2 mm particle size, 50% initial moisture content, and 8 days fermentation time are the best conditions for lovastatin production in SSF. Maximum production of lovastatin using optimized condition was 175.85 and 260.85 mg/kg DM for A. terreus ATCC 20542 and ATCC 74135, respectively, using RS as substrate. PMID:23118499

Synthesis, Characterization, and Antimicrobial Efficacy of Photomicrobicidal Cellulose Paper.

PubMed

Carpenter, Bradley L; Scholle, Frank; Sadeghifar, Hasan; Francis, Aaron J; Boltersdorf, Jonathan; Weare, Walter W; Argyropoulos, Dimitris S; Maggard, Paul A; Ghiladi, Reza A

2015-08-10

Toward our goal of scalable, antimicrobial materials based on photodynamic inactivation, paper sheets comprised of photosensitizer-conjugated cellulose fibers were prepared using porphyrin and BODIPY photosensitizers, and characterized by spectroscopic (infrared, UV-vis diffuse reflectance, inductively coupled plasma optical emission) and physical (gel permeation chromatography, elemental, and thermal gravimetric analyses) methods. Antibacterial efficacy was evaluated against Staphylococcus aureus (ATCC-2913), vancomycin-resistant Enterococcus faecium (ATCC-2320), Acinetobacter baumannii (ATCC-19606), Pseudomonas aeruginosa (ATCC-9027), and Klebsiella pneumoniae (ATCC-2146). Our best results were achieved with a cationic porphyrin-paper conjugate, Por((+))-paper, with inactivation upon illumination (30 min, 65 ± 5 mW/cm(2), 400-700 nm) of all bacterial strains studied by 99.99+% (4 log units), regardless of taxonomic classification. Por((+))-paper also inactivated dengue-1 virus (>99.995%), influenza A (∼ 99.5%), and human adenovirus-5 (∼ 99%). These results demonstrate the potential of cellulose materials to serve as scalable scaffolds for anti-infective or self-sterilizing materials against both bacteria and viruses when employing a photodynamic inactivation mode of action.

Hetero-Diels-Alder reactions of novel 3-triazolyl-nitrosoalkenes as an approach to functionalized 1,2,3-triazoles with antibacterial profile.

PubMed

Lopes, Susana M M; Novais, Juliana S; Costa, Dora C S; Castro, Helena C; Figueiredo, Agnes Marie S; Ferreira, Vitor F; Pinho E Melo, Teresa M V D; da Silva, Fernando de Carvalho

2018-01-01

The generation and reactivity of 3-triazolyl-nitrosoalkenes are reported for the first time. The study showed that hetero-Diels-Alder reaction of these heterodienes is an interesting synthetic strategy to functionalized 1,2,3-triazoles, including 1,2,3-triazolyl-pyrroles, 1,2,3-triazolyl-dipyrromethanes and 1,2,3-triazolyl-indoles. The evaluation of the antibacterial profile against Gram-positive and Gram-negative strains revealed the new 5,5'-diethyldipyrromethane bearing a side chain incorporating a triazole and oxime moieties. The antibacterial profile detected was within the Clinical and Laboratory Standard Institute (CLSI) range and against important Staphylococcus species including Methicillin-resistant strain (S. aureus ATCC 25923, S. epidermidis ATCC 12228 and S. simulans ATCC 27851 and MRSA). Interestingly, this new 1,2,3-triazole presented hemocompatibility and low in silico toxicity profile similar to antibiotics current in use. It also has an usual antibiofilm activity against MRSA, which reinforced its potential as a new antibacterial prototype. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Antibacterial and antifungal properties of human cerumen.

PubMed

Lum, C L; Jeyanthi, S; Prepageran, N; Vadivelu, J; Raman, R

2009-04-01

To assess the antibacterial and antifungal properties of human cerumen by studying its effect on the growth of Staphylococcus aureus, Esherichia coli, Pseudomonas aeruginosa and Candida albicans. Cerumen samples were collected from 75 normal, healthy subjects aged from seven to 80 years, without ear pathology, who attended the ear, nose and throat out-patient clinic of the University Malaya Medical Center from May 2006 to October 2006. Of these 75 samples, 31 had no growth when cultured on nutrient agar. Inhibition studies on these 31 samples were performed for Staphylococcus aureus (American Type Culture Collection (ATCC) 25923), Esherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853) and Candida albicans. Nutrient agar was used to conserve all three bacterial strains and Sabouraud dextrose agar was used for Candida albicans. A decrease in Staphylococcus aureus growth was observed for 27 of the 31 samples. All 31 samples induced decreased growth of Pseudomonas aeruginosa, while 29 induced decreased growth of Candida albicans. However, only four samples induced decreased growth of Escherichia coli. Cerumen was demonstrated to have potential antimicrobial effects on strains of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans.

Regulation of the sol Locus Genes for Butanol and Acetone Formation in Clostridium acetobutylicum ATCC 824 by a Putative Transcriptional Repressor

PubMed Central

Nair, Ramesh V.; Green, Edward M.; Watson, David E.; Bennett, George N.; Papoutsakis, Eleftherios T.

1999-01-01

A gene (orf1, now designated solR) previously identified upstream of the aldehyde/alcohol dehydrogenase gene aad (R. V. Nair, G. N. Bennett, and E. T. Papoutsakis, J. Bacteriol. 176:871–885, 1994) was found to encode a repressor of the sol locus (aad, ctfA, ctfB and adc) genes for butanol and acetone formation in Clostridium acetobutylicum ATCC 824. Primer extension analysis identified a transcriptional start site 35 bp upstream of the solR start codon. Amino acid comparisons of SolR identified a potential helix-turn-helix DNA-binding motif in the C-terminal half towards the center of the protein, suggesting a regulatory role. Overexpression of SolR in strain ATCC 824(pCO1) resulted in a solvent-negative phenotype owing to its deleterious effect on the transcription of the sol locus genes. Inactivation of solR in C. acetobutylicum via homologous recombination yielded mutants B and H (ATCC 824 solR::pO1X) which exhibited deregulated solvent production characterized by increased flux towards butanol and acetone formation, earlier induction of aad, lower overall acid production, markedly improved yields of solvents on glucose, a prolonged solvent production phase, and increased biomass accumulation compared to those of the wild-type strain. PMID:9864345

Decellularized human amniotic membrane: more is needed for an efficient dressing for protection of burns against antibiotic-resistant bacteria isolated from burn patients.

PubMed

Gholipourmalekabadi, M; Bandehpour, M; Mozafari, M; Hashemi, A; Ghanbarian, H; Sameni, M; Salimi, M; Gholami, M; Samadikuchaksaraei, A

2015-11-01

Human amniotic membranes (HAMs) have attracted the attention of burn surgeons for decades due to favorable properties such as their antibacterial activity and promising support of cell proliferation. On the other hand, as a major implication in the health of burn patients, the prevalence of bacteria resistant to multiple antibiotics is increasing due to overuse of antibiotics. The aim of this study was to investigate whether HAMs (both fresh and acellular) are an effective antibacterial agent against antibiotic-resistant bacteria isolated from burn patients. Therefore, a HAM was decellularized and tested for its antibacterial activity. Decellularization of the tissue was confirmed by hematoxylin and eosin (H&E) and 4,6-diamidino-2-phenylindole (DAPI) staining. In addition, the cyto-biocompatibility of the acellular HAM was proven by the cell viability test (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide, MTT) and scanning electron microscopy (SEM). The resistant bacteria were isolated from burns, identified, and tested for their susceptibility to antibiotics using both the antibiogram and polymerase chain reaction (PCR) techniques. Among the isolated bacteria, three blaIMP gene-positive Pseudomonas aeruginosa strains were chosen for their high resistance to the tested antibiotics. The antibacterial activity of the HAM was also tested for Klebsiella pneumoniae (American Type Culture Collection (ATCC) 700603) as a resistant ATCC bacterium; Staphylococcus aureus (mecA positive); and three standard strains of ATCC bacteria including Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27833), and S. aureus (ATCC 25923). Antibacterial assay revealed that only the latter three bacteria were susceptible to the HAM. All the data obtained from this study suggest that an alternative strategy is required to complement HAM grafting in order to fully protect burns from nosocomial infections. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Insertion mutations in Helicobacter pylori flhA reveal strain differences in RpoN-dependent gene expression

PubMed Central

Tsang, Jennifer; Smith, Todd G.; Pereira, Lara E.

2013-01-01

Flagellar biogenesis in the gastric pathogen Helicobacter pylori involves a transcriptional hierarchy that utilizes all three sigma factors found in this bacterium (RpoD, RpoN and FliA). Transcription of the RpoN-dependent genes requires the sensor kinase FlgS and response regulator FlgR. It is thought that FlgS senses some cellular cue to regulate transcription of the RpoN-dependent flagellar genes, but this signal has yet to be identified. Previous studies showed that transcription of the RpoN-dependent genes is inhibited by mutations in flhA, which encodes a membrane-bound component of the flagellar protein export apparatus. We found that depending on the H. pylori strain used, insertion mutations in flhA had different effects on expression of RpoN-dependent genes. Mutations in flhA in H. pylori strains B128 and ATCC 43504 (the type strain) were generated by inserting a chloramphenicol resistance cassette so as to effectively eliminate expression of the gene (ΔflhA), or within the gene following codon 77 (designated flhA77) or codon 454 (designated flhA454), which could allow expression of truncated FlhA proteins. All three flhA mutations severely inhibited transcription of the RpoN-dependent genes flaB and flgE in H. pylori B128. In contrast, levels of flaB and flgE transcripts in H. pylori ATCC 43504 bearing either flhA77 or flhA454, but not ΔflhA, were ~60 % of wild-type levels. The FlhA454 variant was detected in membrane fractions prepared from H. pylori ATCC 43504 but not H. pylori B128, which may account for the phenotypic differences in the flhA mutations of the two strains. Taken together, these findings suggest that only the N-terminal region of FlhA is needed for transcription of the RpoN regulon. Interestingly, expression of an flaB′-′xylE reporter gene in H. pylori ATCC 43504 bearing the flhA77 allele was about eightfold higher than that of a strain with the wild-type allele, suggesting that expression of flaB is not only regulated at the level of transcription but also regulated post-transcriptionally. PMID:23154969

16S-23S rRNA gene internal transcribed spacer sequences for analysis of the phylogenetic relationships among species of the genus Porphyromonas.

PubMed

Conrads, Georg; Citron, Diane M; Tyrrell, Kerin L; Horz, Hans-Peter; Goldstein, Ellie J C

2005-03-01

The 16S-23S rRNA gene internal transcribed spacer (ITS) regions of 11 reference strains of Porphyromonas species, together with Bacteroides distasonis and Tannerella forsythensis, were analysed to examine interspecies relationships. Compared with the phylogenetic tree generated using 16S rRNA gene sequences, the resolution of the ITS sequence-based tree was higher, but species positioning and clustering were similar with both approaches. The recent separation of Porphyromonas gulae and Porphyromonas gingivalis into distinct species was confirmed by the ITS data. In addition, analysis of the ITS sequences of 24 clinical isolates of Porphyromonas asaccharolytica plus the type strain ATCC 25260(T) divided the sequences into two clusters, of which one was alpha-fucosidase-positive (like the type strain) while the other was alpha-fucosidase-negative. The latter resembled the previously studied unusual extra-oral isolates of 'Porphyromonas endodontalis-like organisms' (PELOs) which could therefore be called 'Porphyromonas asaccharolytica-like organisms' (PALOs), based on the genetic identification. Moreover, the proposal of alpha-fucosidase-negative P. asaccharolytica strains as a new species should also be considered.

Porphyromonas canoris sp. nov., an asaccharolytic, black-pigmented species from the gingival sulcus of dogs.

PubMed

Love, D N; Karjalainen, J; Kanervo, A; Forsblom, B; Sarkiala, E; Bailey, G D; Wigney, D I; Jousimies-Somer, H

1994-04-01

A new species, Porphyromonas canoris, is proposed for black-pigmented asaccharolytic strains isolated from subgingival plaque samples from dogs with naturally occurring periodontal disease. This bacterium is an obligately anaerobic, nonmotile, non-spore-forming, gram-negative, rod-shaped organism. On laked rabbit blood or sheep blood agar plates, colonies are light brown to greenish brown after 2 to 4 days of incubation and dark brown after 14 days of incubation. Colonies on egg yolk agar and on nonhemolyzed sheep blood agar are orange. The cells do not grow in the presence of 20% bile and have a guanine-plus-cytosine content of 49 to 51 mol%. The type strain is VPB 4878 (= NCTC 12835). The average levels of DNA-DNA hybridization between P. canoris strains and other members of the genus Porphyromonas are as follows: Porphyromonas gingivalis ATCC 33277T (T = type strain), 6.5%; Porphyromonas gingivalis cat strain VPB 3492, 5%; Porphyromonas endodontalis ATCC 35406T, 1%; Porphyromonas salivosa NCTC 11362T, 5%; and Porphyromonas circumdentaria NCTC 12469T, 6%. The level of hybridization between P. canoris NCTC 12835T DNA and Porphyromonas asaccharolytica ATCC 25260T DNA is 3%. P. canoris cells produce major amounts of acetic, propionic, isovaleric, and succinic acids and minor amounts of isobutyric and butyric acids as end products of metabolism in cooked meat medium. The major cellular fatty acid is 13-methyltetradecanoic acid (iso-C15:0). Glutamate and malate dehydrogenases are present, as are glucose-6-phosphate dehydrogenase activity (65.7 nmol mg of protein-1 min-1) and 6-phosphogluconate dehydrogenase activity (63.0 nmol mg of protein-1 min-1).(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro anti-mycobacterial activities of three species of Cola plant extracts (Sterculiaceae).

PubMed

Adeniyi, B A; Groves, M J; Gangadharam, P R J

2004-05-01

Extracts obtained from three Nigerian Sterculiaceae plants: Cola accuminata, C. nitida and C. milleni were screened for anti-mycobacterium properties using a slow growing Mycobacterium bovis ATCC 35738 (designated BCG Mexican and known to have some virulence in mouse and guinea pig) at 1000 microg/ml using the radiometric (BACTEC) method. The extracts were also tested against six fast growing ATCC strains of M. vaccae using the broth microdilution method. The methanol extracts from both leaves, stem bark and root bark of Cola accuminata and from the leaves and stem bark of C. nitida and C. milleni were not active at the highest concentration of 1000 microg/ml. Only the methanol extract of root bark for both C. nitida and C. milleni were found to be potent against both M. bovis and strains of M. vaccae. The minimum inhibitory concentration (MIC) of C. nitida against M. bovis is 125 microg/ml while the MIC of C. milleni against M. bovis is 62.5 microg/ml after at least 6 days of inhibition with growth index (GI) units lesser than or equal to the change in GI units inoculated with a 1/100 of the BACTEC inoculum for a control vial. The minimum inhibitory concentration of C. milleni against the six ATCC strain of M. vaccae ranged from 62.5 microg/ml to 250 microg/ml while for C. nitida ranged from 500 microg/ml to above 1000microg/ml. Evidently, C. milleni has the highest inhibitory activity against both M. bovis and strains of M. vaccae used. Rifampicin, the positive control used has strong activity against M. bovis at the tested concentration of 5 microg and 10 microg/ml and 4 to 8 microg/ml against the six strains of M. vaccae. Copyright 2004 John Wiley & Sons, Ltd.

Antimicrobial activity of plant essential oils against bacterial and fungal species involved in food poisoning and/or food decay.

PubMed

Lixandru, Brînduşa-Elena; Drăcea, Nicoleta Olguţa; Dragomirescu, Cristiana Cerasella; Drăgulescu, Elena Carmina; Coldea, Ileana Luminiţa; Anton, Liliana; Dobre, Elena; Rovinaru, Camelia; Codiţă, Irina

2010-01-01

The currative properties of aromatic and medicinal plants have been recognized since ancient times and, more recently, the antimicrobial activity of plant essential oils has been used in several applications, including food preservation. The purpose of this study was to create directly comparable, quantitative data on the antimicrobial activity of some plant essential oils prepared in the National Institute of Research-Development for Chemistry and Petrochemistry, Bucharest to be used for the further development of food packaging technology, based on their antibacterial and antifungal activity. The essential oils extracted from thyme (Thymus vulgaris L.), basil (Ocimum basilicum L.), coriander (Coriandrum sativum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.), fennel (Foeniculum vulgare L.), spearmint (Mentha spicata L.) and carraway (Carum carvi L.) were investigated for their antimicrobial activity against eleven different bacterial and three fungal strains belonging to species reported to be involved in food poisoning and/or food decay: S. aureus ATCC 25923, S. aureus ATCC 6538, S. aureus ATCC 25913, E. coli ATCC 25922, E. coli ATCC 35218, Salmonella enterica serovar Enteritidis Cantacuzino Institute Culture Collection (CICC) 10878, Listeria monocytogenes ATCC 19112, Bacillus cereus CIP 5127, Bacillus cereus ATCC 11778, Candida albicans ATCC 10231, Aspergillus niger ATCC 16404, Penicillium spp. CICC 251 and two E. coli and Salmonella enterica serovar Enteritidis clinical isolates. The majority of the tested essential oils exibited considerable inhibitory capacity against all the organisms tested, as supported by growth inhibition zone diameters, MICs and MBC's. Thyme, coriander and basil oils proved the best antibacterial activity, while thyme and spearmint oils better inhibited the fungal species.

Biological and Chemical Diversity of Bacteria Associated with a Marine Flatworm.

PubMed

Lin, Hui-Na; Wang, Kai-Ling; Wu, Ze-Hong; Tian, Ren-Mao; Liu, Guo-Zhu; Xu, Ying

2017-09-01

The aim of this research is to explore the biological and chemical diversity of bacteria associated with a marine flatworm Paraplanocera sp., and to discover the bioactive metabolites from culturable strains. A total of 141 strains of bacteria including 45 strains of actinomycetes and 96 strains of other bacteria were isolated, identified and fermented on a small scale. Bioactive screening (antibacterial and cytotoxic activities) and chemical screening (ultra-performance liquid chromatography-mass spectrometry (UPLC-MS)) yielded several target bacterial strains. Among these strains, the ethyl acetate (EA) crude extract of Streptomyces sp. XY-FW47 fermentation broth showed strong antibacterial activity against methicillin-resistant Staphylococcus aureus ATCC43300 (MRSA ATCC43300) and potent cytotoxic effects on HeLa cells. The UPLC-MS spectral analysis of the crude extract indicated that the strain XY-FW47 could produce a series of geldanamycins (GMs). One new geldanamycin (GM) analog, 4,5-dihydro-17-O-demethylgeldanamycin (1), and three known GMs (2-4) were obtained. All of these compounds were tested for antibacterial, cytotoxic, and antifungal activities, yet only GM (3) showed potent cytotoxic (HeLa cells, EC 50 = 1.12 μg/mL) and antifungal ( Setosphaeria turcica MIC = 2.40 μg/mL) activities. Their structure-activity relationship (SAR) was also preliminarily discussed in this study.

Determination of Active Phagocytosis of Unopsonized Porphyromonas gingivalis by Macrophages and Neutrophils Using the pH-Sensitive Fluorescent Dye pHrodo

PubMed Central

Lenzo, Jason C.; O'Brien-Simpson, Neil M.; Cecil, Jessica; Holden, James A.

2016-01-01

Phagocytosis of pathogens is an important component of the innate immune system that is responsible for the removal and degradation of bacteria as well as their presentation via the major histocompatibility complexes to the adaptive immune system. The periodontal pathogen Porphyromonas gingivalis exhibits strain heterogeneity, which may affect a phagocyte's ability to recognize and phagocytose the bacterium. In addition, P. gingivalis is reported to avoid phagocytosis by antibody and complement degradation and by invading phagocytic cells. Previous studies examining phagocytosis have been confounded by both the techniques employed and the potential of the bacteria to invade the cells. In this study, we used a novel, pH-sensitive dye, pHrodo, to label live P. gingivalis strains and examine unopsonized phagocytosis by murine macrophages and neutrophils and human monocytic cells. All host cells examined were able to recognize and phagocytose unopsonized P. gingivalis strains. Macrophages had a preference to phagocytose P. gingivalis strain ATCC 33277 over other strains and clinical isolates in the study, whereas neutrophils favored P. gingivalis W50, ATCC 33277, and one clinical isolate over the other strains. This study revealed that all P. gingivalis strains were capable of being phagocytosed without prior opsonization with antibody or complement. PMID:27021243

Veillonella infantium sp. nov., an anaerobic, Gram-stain-negative coccus isolated from tongue biofilm of a Thai child.

PubMed

Mashima, Izumi; Liao, Yu-Chieh; Miyakawa, Hiroshi; Theodorea, Citra F; Thawboon, Boonyanit; Thaweboon, Sroisiri; Scannapieco, Frank A; Nakazawa, Futoshi

2018-04-01

A strain of a novel anaerobic, Gram-stain-negative coccus was isolated from the tongue biofilm of a Thai child. This strain was shown, at the phenotypic level and based on 16S rRNA gene sequencing, to be a member of the genus Veillonella. Comparative analysis of the 16S rRNA, dnaK and rpoB gene sequences indicated that phylogenetically the strain comprised a distinct novel branch within the genus Veillonella. The novel strain showed 99.8, 95.1 and 95.9 % similarity to partial 16S rRNA, dnaK and rpoB gene sequences, respectively, to the type strains of the two most closely related species, Veillonelladispar ATCC 17748 T and Veillonellatobetsuensis ATCC BAA-2400 T . The novel strain could be discriminated from previously reported species of the genus Veillonella based on partial dnaK and rpoB gene sequencing and average nucleotide identity values. The major acid end-product produced by this strain was acetic acid under anaerobic conditions in trypticase-yeast extract-haemin with 1 % (w/v) glucose or fructose medium. Lactate was fermented to acetic acid and propionic acid. Based on these observations, this strain represents a novel species, for which the name Veillonella infantium sp. nov. is proposed. The type strain is T11011-4 T (=JCM 31738 T =TSD-88 T ).

Antimicrobial activity of the bioactive components of essential oils from Pakistani spices against Salmonella and other multi-drug resistant bacteria

PubMed Central

2013-01-01

Background The main objective of this study was the phytochemical characterization of four indigenous essential oils obtained from spices and their antibacterial activities against the multidrug resistant clinical and soil isolates prevalent in Pakistan, and ATCC reference strains. Methods Chemical composition of essential oils from four Pakistani spices cumin (Cuminum cyminum), cinnamon (Cinnamomum verum), cardamom (Amomum subulatum) and clove (Syzygium aromaticum) were analyzed on GC/MS. Their antibacterial activities were investigated by minimum inhibitory concentration (MIC) and Thin-Layer Chromatography-Bioautographic (TLC-Bioautographic) assays against pathogenic strains Salmonella typhi (D1 Vi-positive), Salmonella typhi (G7 Vi-negative), Salmonella paratyphi A, Escherichia coli (SS1), Staphylococcus aureus, Pseudomonas fluorescens and Bacillus licheniformis (ATCC 14580). The data were statistically analyzed by using Analysis of Variance (ANOVA) and Least Significant Difference (LSD) method to find out significant relationship of essential oils biological activities at p <0.05. Results Among all the tested essential oils, oil from the bark of C. verum showed best antibacterial activities against all selected bacterial strains in the MIC assay, especially with 2.9 mg/ml concentration against S. typhi G7 Vi-negative and P. fluorescens strains. TLC-bioautography confirmed the presence of biologically active anti-microbial components in all tested essential oils. P. fluorescens was found susceptible to C. verum essential oil while E. coli SS1 and S. aureus were resistant to C. verum and A. subulatum essential oils, respectively, as determined in bioautography assay. The GC/MS analysis revealed that essential oils of C. cyminum, C. verum, A. subulatum, and S. aromaticum contain 17.2% cuminaldehyde, 4.3% t-cinnamaldehyde, 5.2% eucalyptol and 0.73% eugenol, respectively. Conclusions Most of the essential oils included in this study possessed good antibacterial activities against selected multi drug resistant clinical and soil bacterial strains. Cinnamaldehyde was identified as the most active antimicrobial component present in the cinnamon essential oil which acted as a strong inhibitory agent in MIC assay against the tested bacteria. The results indicate that essential oils from Pakistani spices can be pursued against multidrug resistant bacteria. PMID:24119438

Treponema putidum sp. nov., a medium-sized proteolytic spirochaete isolated from lesions of human periodontitis and acute necrotizing ulcerative gingivitis.

PubMed

Wyss, C; Moter, A; Choi, B-K; Dewhirst, F E; Xue, Yi; Schüpbach, P; Göbel, U B; Paster, B J; Guggenheim, B

2004-07-01

So far, little phenotypic heterogeneity has been detected in cultured oral treponemes with trypsin-like proteolytic activity, and all have been assigned to the species Treponema denticola. However, comparisons of protein patterns and antigen expression in our collection of proteolytic oral treponemes occasionally identified isolates with a unique phenotype; e.g. strain OMZ 830 (=ATCC 700768), which qualified as a 'pathogen-related oral spirochaete' due to the presence of a approximately 37 kDa protein reactive with the Treponema pallidum FlaA-specific mAb H9-2. In addition to such single isolates, a homogeneous group of seven independent strains is described that were highly motile, medium-sized, proteolytic but asaccharolytic spirochaetes and were cultured from human gingivitis, periodontitis and acute necrotizing ulcerative gingivitis in medium OMIZ-Pat supplemented with 1% human serum and antibiotics. Growth of these spirochaetes in OMIZ-Pat was not dependent on, but was stimulated by, human or bovine serum. Carbohydrates were neither required nor stimulatory for growth. The protein and antigen patterns of total cell extracts of these organisms separated by SDS-PAGE were distinct from those of all previously cultured spirochaetes, with highest similarity to T. denticola. The novel spirochaete has a 2 : 4 : 2 arrangement of the periplasmic flagella, similar to T. denticola. However, the flagellin pattern as detected by immunostaining or glycan staining of Western blots readily distinguished the novel group from T. denticola. Also, distinct from reference strains of T. denticola, none of the novel isolates displayed sialidase or dentilisin activities, both of which are expressed by most strains of T. denticola. Trypsin-like activity and other enzymes as detected by API ZYM test were similar to those of T. denticola. The status of a novel species is supported by the 16S rRNA gene sequence, with 98.5% similarity to its closest cultured relative, T. denticola. The name Treponema putidum sp. nov. is proposed (type strain OMZ 758T=ATCC 700334T=CIP 108088T).

Development of Bioluminescent Cronobacter sakazakii ATCC 29544 in a Mouse Model.

PubMed

Wang, Xiwen; Li, Zhiping; Dong, Xiaolin; Chi, Hang; Wang, Guannan; Li, Jiakuan; Sun, Rui; Chen, Man; Zhang, Xinying; Wang, Yuanyuan; Qu, Han; Sun, Yu; Xia, Zhiping; Li, Qianxue

2015-05-01

Cronobacter sakazakii is an emerging pathogen that causes severe and life-threatening conditions including meningitis, bacteremia, and necrotizing enterocolitis. An animal model study for extrapolation of C. sakazakii infection can provide a better understanding of pathogenesis. However, methods for real-time monitoring of the course of C. sakazakii infection in living animals have been lacking. We developed a bioluminescent C. sakazakii strain (ATCC 29544) that can be used for real-time monitoring of C. sakazakii infection in BALB/c mice. C. sakazakii ATCC 29544 mainly colonized brain, liver, spleen, kidney, and gastrointestinal tract, as indicated by bioluminescence imaging. This work provides a novel approach for studying the progression of C. sakazakii infection and evaluating therapeutics in a living mouse model.

Influence of bovine lactoferrin on the growth of selected probiotic bacteria under aerobic conditions.

PubMed

Chen, Po-Wen; Ku, Yu-We; Chu, Fang-Yi

2014-10-01

Bovine lactoferrin (bLf) is a natural glycoprotein, and it shows broad-spectrum antimicrobial activity. However, reports on the influences of bLf on probiotic bacteria have been mixed. We examined the effects of apo-bLf (between 0.25 and 128 mg/mL) on both aerobic and anaerobic cultures of probiotics. We found that bLf had similar effects on the growth of probiotics under aerobic or anaerobic conditions, and that it actively and significantly (at concentrations of >0.25 mg/mL) retarded the growth rate of Bifidobacterium bifidum (ATCC 29521), B. longum (ATCC 15707), B. lactis (BCRC 17394), B. infantis (ATCC 15697), Lactobacillus reuteri (ATCC 23272), L. rhamnosus (ATCC 53103), and L. coryniformis (ATCC 25602) in a dose-dependent manner. Otherwise, minimal inhibitory concentrations (MICs) were 128 or >128 mg/mL against B. bifidum, B. longum, B. lactis, L. reuteri, and L. rhamnosus (ATCC 53103). With regard to MICs, bLf showed at least four-fold lower inhibitory effect on probiotics than on pathogens. Intriguingly, bLf (>0.25 mg/mL) significantly enhanced the growth of Rhamnosus (ATCC 7469) and L. acidophilus (BCRC 14065) by approximately 40-200 %, during their late periods of growth. Supernatants produced from aerobic but not anaerobic cultures of L. acidophilus reduced the growth of Escherichia coli by about 20 %. Thus, bLf displayed a dose-dependent inhibitory effect on the growth of most probiotic strains under either aerobic or anaerobic conditions. An antibacterial supernatant prepared from the aerobic cultures may have significant practical use.

Evaluation of probiotic properties of Lactobacillus plantarum WLPL04 isolated from human breast milk.

PubMed

Jiang, Meiling; Zhang, Fen; Wan, Cuixiang; Xiong, Yonghua; Shah, Nagendra P; Wei, Hua; Tao, Xueying

2016-03-01

Lactobacillus plantarum WLPL04, a specific strain isolated from human breast milk, was investigated for its survival capacity (acid and bile salt tolerance, survival in simulated gastrointestinal tract, inhibition of pathogens, antibiotic susceptibility, yield of exopolysaccharides) and probiotic properties (antiadhesion of pathogens, protection from harmful effect of sodium dodecyl sulfate, and antiinflammatory stress on Caco-2 cells). The results showed that Lb. plantarum WLPL04 had broad-spectrum activity against gram-positive strains (Listeria monocytogenes CMCC54007, Bacillus cereus ATCC14579, and Staphylococcus aureus CMCC26003) and gram-negative strains (Pseudomonas aeruginosa MCC10104, Shigella sonnei ATCC25931, Enterobacter sakazakii ATCC29544, Salmonella typhimurium ATCC13311, and Escherichia coli O157:H7). Antibiotic susceptibility tests showed that Lb. plantarum WLPL04 was susceptible to 8 of 14 antibiotics (e.g., erythromycin and nitrofurantoin) and resistant to 6 of 14 antibiotics (e.g., kanamycin and bacitracin). Lactobacillus plantarum WLPL04 was able to survive at pH 2.5 for 3h and at 0.45% bile salt for 12h, suggesting that it can survive well in the gastrointestinal tract. In addition, the exopolysaccharide yield of Lb. plantarum WLPL04 reached 426.73 ± 65.56 mg/L at 24h. With strategies of competition, inhibition, and displacement, Lb. plantarum WLPL04 reduced the adhesion of E. coli O157:H7 (35.51%), Sal. typhimurium ATCC 13311 (8.10%), and Staph. aureus CMCC 26003 (40.30%) on Caco-2 cells by competition, and subsequently by 59.80, 62.50, and 42.60%, respectively, for the 3 pathogens through inhibition, and by 75.23, 39.97, and 52.88%, respectively, through displacement. Lactobacillus plantarum WLPL04 attenuated the acute stress induced by sodium dodecyl sulfate on Caco-2 cells and significantly inhibited the expression of inflammatory cytokines (IL-6, IL-8 and tumor necrosis factor-α) on Caco-2 cells but increased IL-10 expression in vitro compared with the Salmonella-treated group. In summary, Lb. plantarum WLPL04 from breast milk could be considered as a probiotic candidate for dairy products to promote human health. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Survival of Escherichia coli O157:H7 ATCC 43895 in a Model Apple Juice Medium with Different Concentrations of Proline and Caffeic Acid

PubMed Central

Reinders, Robert D.; Biesterveld, Steef; Bijker, Peter G. H.

2001-01-01

The effects of proline and caffeic acid on the survival of Shiga toxin-producing Escherichia coli (STEC) O157:H7 strain ATCC 43895 in a model apple juice medium were studied. It is hypothesized that the inhibitory effect of caffeic acid may explain why almost all outbreaks of STEC O157:H7 infections linked to apple juice or cider have occurred in October or November. PMID:11375209

Oscillating behavior of carbohydrate granule formation and dinitrogen fixation in the cyanobacterium Cyanothece sp. strain ATCC 51142

NASA Technical Reports Server (NTRS)

Schneegurt, M. A.; Sherman, D. M.; Nayar, S.; Sherman, L. A.; Mitchell, C. A. (Principal Investigator)

1994-01-01

It has been shown that some aerobic, unicellular, diazotrophic cyanobacteria temporally separate photosynthetic O2 evolution and oxygen-sensitive N2 fixation. Cyanothece sp. ATCC strain 51142 is an aerobic, unicellular, diazotrophic cyanobacterium that fixes N2 during discrete periods of its cell cycle. When the bacteria are maintained under diurnal light-dark cycles, N2 fixation occurs in the dark. Similar cycling is observed in continuous light, implicating a circadian rhythm. Under N2-fixing conditions, large inclusion granules form between the thylakoid membranes. Maximum granulation, as observed by electron microscopy, occurs before the onset of N2 fixation, and the granules decrease in number during the period of N2 fixation. The granules can be purified from cell homogenates by differential centrifugation. Biochemical analyses of the granules indicate that these structures are primarily carbohydrate, with some protein. Further analyses of the carbohydrate have shown that it is a glucose polymer with some characteristics of glycogen. It is proposed that N2 fixation is driven by energy and reducing power stored in these inclusion granules. Cyanothece sp. strain ATCC 51142 represents an excellent experimental organism for the study of the protective mechanisms of nitrogenase, metabolic events in cyanobacteria under normal and stress conditions, the partitioning of resources between growth and storage, and biological rhythms.

Cloxacillin control of experimental arthritis induced by SEC(+) Staphylococcus aureus is associated with downmodulation of local and systemic cytokines.

PubMed

Colavite, Priscila Maria; Ishikawa, Larissa Lumi Watanabe; Zorzella-Pezavento, Sofia Fernanda Gonçalves; Oliveira, Larissa Ragozo Cardoso de; França, Thaís Graziela Donegá; da Rosa, Larissa Camargo; Chiuso-Minicucci, Fernanda; Vieira, Andreia Espíndola; Francisconi, Carolina Fávaro; da Cunha, Maria de Lourdes Ribeiro de Souza; Garlet, Gustavo Pompermaier; Sartori, Alexandrina

2016-07-01

Staphylococcus aureus is the most common agent of septic arthritis (SA) that is a severe, rapidly progressive and erosive disease. In this work we investigated the clinical, histopathological and immunological characteristics of the SA triggered by an enterotoxin C producer S. aureus strain. The effect of a β-lactamic antibiotic over disease evolution and cytokine production was also evaluated. After confirmation that ATCC 19095 SEC(+) strain preserved its ability to produce enterotoxin C, this bacteria was used to infect C57BL/6 male mice. Body weight, clinical score and disease prevalence were daily evaluated during 14 days. Cytokine production by splenocytes, cytokine mRNA expression in arthritic lesions, transcription factors mRNA expression in inguinal lymph nodes and histopathological analysis were performed 7 and 14 days after infection. ATCC 19095 SEC(+) strain caused a severe arthritis characterized by weight loss, high clinical scores and a 100% disease prevalence. Histopathological analysis revealed inflammation, pannus formation and bone erosion. Arthritis aggravation was associated with elevated production of pro-inflammatory cytokines, higher local mRNA expression of these cytokines and also higher mRNA expression of T-bet, ROR-γ and GATA-3. Disease control by cloxacillin was associated with decreased production of pro-inflammatory cytokines but not of IL-10. These findings indicate that the ATCC 19095 SEC(+) strain is able to initiate a severe septic arthritis in mice associated with elevated cytokine production that can be, however, controlled by cloxacillin. © 2015 John Wiley & Sons Ltd.

THz+X Seedling Report

DTIC Science & Technology

2005-11-23

lamblia Entamoeba histolytica Toxoplasma Microsporidia Additional viral encephalitides West Nile Virus LaCrosse California encephalitis VEE...Is Catalyzed by Salicylate 1- Monooxygenase from Pseudomonas sp . Strain ATCC 29352; Applied and Environmental Microbiology, July 2004, p. 4040-4047...the Mechanism of RDX Biodegradation by Rhodococcus - 31 - sp . Strain DN22; Applied and Environmental Microbiology, March 2003, p. 1347-1351

Production of astaxanthin from cellulosic biomass sugars by mutants of the yeast Phaffia rhodozyma

USDA-ARS?s Scientific Manuscript database

Astaxanthin is a carotenoid of high value to the aquaculture, nutraceutical, and pharmaceutical industries. Three mutant strains of the astaxanthin-producing yeast Phaffia rhodozyma, which were derived from the parent strain ATCC 24202 (UCD 67-210) and designated JTM166, JTM185, and SSM19, were test...

Yeasts isolated from Algerian infants's feces revealed a burden of Candida albicans species, non-albicans Candida species and Saccharomyces cerevisiae.

PubMed

Seddik, Hamza Ait; Ceugniez, Alexandre; Bendali, Farida; Cudennec, Benoit; Drider, Djamel

2016-01-01

This study aimed at showing the yeast diversity in feces of Algerian infants, aged between 1 and 24 months, hospitalized at Bejaia hospital (northeast side of the country). Thus, 20 colonies with yeast characteristics were isolated and identified using biochemical (ID32C Api system) and molecular (sequencing of ITS1-5.8S-ITS2 region) methods. Almost all colonies isolated (19 strains) were identified as Candida spp., with predominance of Candida albicans species, and one strain was identified as Saccharomyces cerevisiae. Screening of strains with inhibitory activities unveiled the potential of Candida parapsilosis P48L1 and Candida albicans P51L1 to inhibit the growth of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. Further studies performed with these two Candida strains revealed their susceptibility to clinically used antifungal compounds and were then characterized for their cytotoxicity and hemolytic properties. On the other hand, Saccharomyces cerevisiae P9L1 isolated as well in this study was shown to be devoid of antagonism but resulted safe and overall usable as probiotic.

Clavulanic acid production by the MMS 150 mutant obtained from wild type Streptomyces clavuligerus ATCC 27064

PubMed Central

da Silva Vasconcelos, Eliton; de Lima, Vanderlei Aparecido; Goto, Leandro Seiji; Cruz-Hernández, Isara Lourdes; Hokka, Carlos Osamu

2013-01-01

Clavulanic acid (CA) is a powerful inhibitor of the beta-lactamases, enzymes produced by bacteria resistants to penicillin and cefalosporin. This molecule is produced industrially by strains of Streptomyces clavuligerus in complex media which carbon and nitrogen resources are supplied by inexpensive compounds still providing high productivity. The genetic production improvement using physical and chemical mutagenic agents is an important strategy in programs of industrial production development of bioactive metabolites. However, parental strains are susceptible to loss of their original productivity due genetic instability phenomenona. In this work, some S. clavuligerus mutant strains obtained by treatment with UV light and with MMS are compared with the wild type (Streptomyces clavuligerus ATCC 27064). The results indicated that the random mutations originated some strains with different phenotypes, most divergent demonstrated by the mutants strains named AC116, MMS 150 and MMS 54, that exhibited lack of pigmentation in their mature spores. Also, the strain MMS 150 presented a larger production of CA when cultivated in semi-synthetics media. Using other media, the wild type strain obtained a larger CA production. Besides, using the modifed complex media the MMS 150 strain showed changes in its lipolitic activity and a larger production of CA. The studies also allowed finding the best conditions for a lipase activity exhibited by wild type S. clavuligerus and the MMS150 mutant. PMID:24688492

Response of Lactobacillus acidophilus ATCC 4356 to low-shear modeled microgravity

NASA Astrophysics Data System (ADS)

Castro-Wallace, Sarah; Stahl, Sarah; Voorhies, Alexander; Lorenzi, Hernan; Douglas, Grace L.

2017-10-01

The introduction of probiotic microbes into the spaceflight food system has the potential for use as a safe, non-invasive, daily countermeasure to crew microbiome and immune dysregulation. However, the microgravity effects on the stress tolerances and gene expression of probiotic bacteria must be investigated to confirm that benefits of selected strains will still be conveyed under microgravity conditions. The goal of this study was to evaluate the characteristics of the probiotic bacteria Lactobacillus acidophilus ATCC 4356 in a microgravity analog environment. L. acidophilus was cultured anaerobically under modeled microgravity conditions and assessed for differences in growth, survival through stress challenge, and gene expression compared to control cultures. No significant differences were observed between the modeled microgravity and control grown L. acidophilus, suggesting that this strain will behave similarly in spaceflight.

Invasion of vascular cells in vitro by Porphyromonas endodontalis.

PubMed

Dorn, B R; Harris, L J; Wujick, C T; Vertucci, F J; Progulske-Fox, A

2002-04-01

The objective of this study was to determine whether laboratory strains and clinical isolates of microorganisms associated with root canal infections can invade primary cultures of cardiovascular cells. Quantitative levels of bacterial invasion of human coronary artery endothelial cells (HCAEC) and coronary artery smooth muscle cells (CASMC) were measured using a standard antibiotic protection assay. Transmission electron microscopy was used to confirm and visualize internalization within the vascular cells. Of the laboratory and clinical strains tested, only P. endodontalis ATCC 35406 was invasive in an antibiotic protection assay using HCAEC and CASMC. Invasion of P. endodontalis ATCC 35406 was confirmed by transmission electron microscopy. Certain microorganisms associated with endodontic infections are invasive. If bacterial invasion of the vasculature contributes to the pathogenesis of cardiovascular disease, then microorganisms in the pulp chamber represent potential pathogens.

Identification of the uridine 5'-diphosphoglucose (UDP-Glc) binding subunit of cellulose synthase in Acetobacter xylinum using the photoaffinity probe 5-azido-UDP-Glc

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, F.C.; Brown, R.M. Jr.; Drake, R.R. Jr.

1990-03-25

Photoaffinity labeling of purified cellulose synthase with (beta-32P)5-azidouridine 5'-diphosphoglucose (UDP-Glc) has been used to identify the UDP-Glc binding subunit of the cellulose synthase from Acetobacter xylinum strain ATCC 53582. The results showed exclusive labeling of an 83-kDa polypeptide. Photoinsertion of (beta-32P)5-azido-UDP-Glc is stimulated by the cellulose synthase activator, bis-(3'----5') cyclic diguanylic acid. Addition of increasing amounts of UDP-Glc prevents photolabeling of the 83-kDa polypeptide. The reversible and photocatalyzed binding of this photoprobe also showed saturation kinetics. These studies demonstrate that the 83-kDa polypeptide is the catalytic subunit of the cellulose synthase in A. xylinum strain ATCC 53582.

Photobacterium damselae ssp. piscicida: detection by direct amplification of 16S rRNA gene sequences and genotypic variation as determined by amplified fragment length polymorphism (AFLP).

PubMed

Kvitt, H; Ucko, M; Colorni, A; Batargias, C; Zlotkin, A; Knibb, W

2002-04-05

A PCR protocol for the rapid diagnosis of fish 'pasteurellosis' based on 16S rRNA gene sequences was developed. The procedure combines low annealing temperature that detects low titers of Photobacterium damselae but also related species, and high annealing temperature for the specific identification of P. damselae directly from infected fish. The PCR protocol was validated on 19 piscine isolates of P. damselae ssp. piscicida from different geographic regions (Japan, Italy, Spain, Greece and Israel), on spontaneously infected sea bream Sparus aurata and sea bass Dicentrarchus labrax, and on closely related American Type Culture Collection (ATCC) reference strains. PCR using high annealing temperature (64 degrees C) discriminated between P. damselae and closely related reference strains, including P. histaminum. Sixteen isolates of P. damselae ssp. piscicida, 2 P. damselae ssp. piscicida reference strains and 1 P. damselae ssp. damselae reference strain were subjected to Amplified Fragment Length Polymorphism (AFLP) analysis, and a similarity matrix was produced. Accordingly, the Japanese isolates of P. damselae ssp. piscicida were distinguished from the Mediterranean/European isolates at a cut-off value of 83% similarity. A further subclustering at a cut-off value of 97% allowed discrimination between the Israeli P. damselae ssp. piscicida isolates and the other Mediterranean/European isolates. The combination of PCR direct amplification and AFLP provides a 2-step procedure, where P. damselae is rapidly identified at genus level on the basis of its 16S rRNA gene sequence and then grouped into distinct clusters on the basis of AFLP polymorphisms. The first step of direct amplification is highly sensitive and has immediate practical consequences, offering fish farmers a rapid diagnosis, while the AFLP is more specific and detects intraspecific variation which, in our study, also reflected geographic correspondence. Because of its superior discriminative properties, AFLP can be an important tool for epidemiological and taxonomic studies of this highly homogeneous genus.

Isolation and characterization of cyclo-(tryptophanyl-prolyl) and chloramphenicol from Streptomyces sp. SUK 25 with antimethicillin-resistant Staphylococcus aureus activity

PubMed Central

Alshaibani, Muhanna M; Jalil, Juriyati; Sidik, Nik M; Edrada-Ebel, Ruangelie; Zin, Noraziah M

2016-01-01

Background Zingiber spectabile, commonly known as Beehive Ginger, is used as an ethnobotanical plant in many countries as an appetizer or to treat stomachache, toothache, muscle sprain, and as a cure for swelling, sores and cuts. This is the first report of isolation of Streptomyces strain from the root of this plant. Strain Universiti Kebangsaan 25 (SUK 25) has a very high activity to produce secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA), which is associated with high morbidity and mortality rates due to acquired multidrug resistance genes and causes medication failure in some clinical cases worldwide. Phylogenetic analysis based on the 16S ribosomal RNA gene sequence exhibited that the most closely related strain was Streptomyces omiyaensis NBRC 13449T (99.0% similarity). Aim This study was conducted to carry out the extraction, identification, and biological evaluation of active metabolites isolated from SUK 25 against three MRSA strains, namely, MRSA ATCC 43300, MRSA ATCC 33591, and MRSA ATCC 49476. Materials and methods The production of secondary metabolites by this strain was optimized through Thronton’s media. Isolation, purification, and identification of the bioactive compounds were carried out using reversed-phase high-performance liquid chromatography, high-resolution mass spectrometry, Fourier transform infrared, and one-dimensional and two-dimensional nuclear magnetic resonance. Results During screening procedure, SUK 25 exhibited good antimicrobial potential against several strains of MRSA. The best biological activity was shown from fraction number VII and its subfractions F2 and F3 with minimum inhibitory concentration values at 16 µg/mL and 8 µg/mL, respectively. These two subfractions were identified as diketopiperazine cyclo-(tryptophanyl-prolyl) and chloramphenicol. Conclusion On the basis of obtained results, SUK 25 isolated from Z. spectabile can be regarded as a new valuable source to produce secondary metabolites against bacteria, especially MRSA. PMID:27330275

Newly Isolated Paenibacillus tyrfis sp. nov., from Malaysian Tropical Peat Swamp Soil with Broad Spectrum Antimicrobial Activity

PubMed Central

Aw, Yoong-Kit; Ong, Kuan-Shion; Lee, Learn-Han; Cheow, Yuen-Lin; Yule, Catherine M.; Lee, Sui-Mae

2016-01-01

Emergence of antimicrobial resistance coupled with the slowdown in discovery of new antimicrobial compounds points to serious consequences for human health. Therefore, scientists are looking for new antimicrobial compounds from unique and understudied ecosystems such as tropical peat swamp forests. Over the course of isolating antimicrobial producing bacteria from North Selangor tropical peat swamp forest, Malaysia, a Gram variable, rod shaped, endospore forming, facultative anaerobic novel strain MSt1T that exerts potent and broad spectrum antimicrobial activity was isolated. Phylogenetic analysis using 16S rRNA gene sequences showed that strain MSt1T belonged to the genus Paenibacillus with the highest similarity to Paenibacillus elgii SD17T (99.5%). Whole genome comparison between strain MSt1T with its closely related species using average nucleotide identity (ANI) revealed that similarity between strain MSt1T with P. elgii B69 (93.45%) and Paenibacillus ehimensis A2 (90.42%) was below the recommended threshold of 95%. Further analysis using in silico pairwise DDH also showed that similarity between strain MSt1T with P. elgii B69 (55.4%) and P. ehimensis A2 (43.7%) was below the recommended threshold of 70%. Strain MSt1T contained meso-diaminopilemic acid in the cell wall and MK-7 as the major menaquinone. The major fatty acids of strain MSt1T were anteiso-C15:0 (48.2%) and C16:0 (29.0%) whereas the polar lipid profile consisted of phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, one unknown lipid, two unknown glycolipids, and one unknown phospholipid. Total DNA G+C content of strain MSt1T was 51.5 mol%. The extract from strain MSt1T exerted strong antimicrobial activity against Escherichia coli ATCC 25922 (MIC = 1.5 μg/mL), MRSA ATCC 700699 (MIC = 25 μg/mL) and Candida albicans IMR (MIC = 12.5 μg/mL). Partially purified active fraction exerted a strong effect against E. coli ATCC 25922 resulting in cell rupture when viewed with SEM. Based on distinctive taxonomic differences between strain MSt1T when compared to its closely related type species, we propose that strain MSt1T represents a novel species within the genus of Paenibacillus, for which the name Paenibacillus tyrfis sp. nov. (= DSM 100708T = MCCC 1K01247T) is proposed. PMID:26973605

Internalization of the PDZ and its photodynamic effect on the growth of ATCC and clinical strains of E. coli and S. aureus

NASA Astrophysics Data System (ADS)

Rodrigues da Silva, Gislene; Henrique Correia Pereira, André; Guerra Pinto, Juliana; José Raniero, Leandro; Ferreira-Strixino, Juliana

2016-09-01

The treatment of bacterial infections has been a challenge after the end of the ‘era of antibiotics’. Bacteria are capable of causing many infectious diseases; therefore, with the increasing number of bacteria becoming resistant, development of alternative therapies is needed to minimize, or even eliminate the use of antibiotics. Photodynamic therapy (PDT) is a promising alternative to fight microorganism. In view of the increasing emergence of resistant bacteria and the limitations of conventional treatment, this study evaluated the effect of photodynamic therapy with photodithazine (PDZ) in inactivating bacterial strains of E. coli and S. aureus in vitro, comparing the behavior of clinical and ATCC strains. Confocal microscopy analysis was performed to determine the internalization of the PS and spectrophotometric technique was used to determine the growth of bacteria in vitro. PDT using PDZ was able to reduce the growth of S. aureus strains using the incubation time of 24 h, whereas no satisfactory results were obtained with 15 min incubation. The E. coli strains, tested at two incubation times, did not affectively reduce bacterial growth. Therefore, it is concluded that PDT using PDZ is viable when applied to the S. aureus strains, when suitable incubation times are used.

Complete Genome Sequence and Comparative Analysis of the Fish Pathogen Lactococcus garvieae

PubMed Central

Oshima, Kenshiro; Yoshizaki, Mariko; Kawanishi, Michiko; Nakaya, Kohei; Suzuki, Takehito; Miyauchi, Eiji; Ishii, Yasuo; Tanabe, Soichi; Murakami, Masaru; Hattori, Masahira

2011-01-01

Lactococcus garvieae causes fatal haemorrhagic septicaemia in fish such as yellowtail. The comparative analysis of genomes of a virulent strain Lg2 and a non-virulent strain ATCC 49156 of L. garvieae revealed that the two strains shared a high degree of sequence identity, but Lg2 had a 16.5-kb capsule gene cluster that is absent in ATCC 49156. The capsule gene cluster was composed of 15 genes, of which eight genes are highly conserved with those in exopolysaccharide biosynthesis gene cluster often found in Lactococcus lactis strains. Sequence analysis of the capsule gene cluster in the less virulent strain L. garvieae Lg2-S, Lg2-derived strain, showed that two conserved genes were disrupted by a single base pair deletion, respectively. These results strongly suggest that the capsule is crucial for virulence of Lg2. The capsule gene cluster of Lg2 may be a genomic island from several features such as the presence of insertion sequences flanked on both ends, different GC content from the chromosomal average, integration into the locus syntenic to other lactococcal genome sequences, and distribution in human gut microbiomes. The analysis also predicted other potential virulence factors such as haemolysin. The present study provides new insights into understanding of the virulence mechanisms of L. garvieae in fish. PMID:21829716

Lactobacillus acidophilus ATCC 4356 inhibits biofilm formation by C. albicans and attenuates the experimental candidiasis in Galleria mellonella.

PubMed

Vilela, Simone F G; Barbosa, Júnia O; Rossoni, Rodnei D; Santos, Jéssica D; Prata, Marcia C A; Anbinder, Ana Lia; Jorge, Antonio O C; Junqueira, Juliana C

2015-01-01

Probiotic strains of Lactobacillus have been studied for their inhibitory effects on Candida albicans. However, few studies have investigated the effect of these strains on biofilm formation, filamentation and C. albicans infection. The objective of this study was to evaluate the influence of Lactobacillus acidophilus ATCC 4356 on C. albicans ATCC 18804 using in vitro and in vivo models. In vitro analysis evaluated the effects of L. acidophilus on the biofilm formation and on the capacity of C. albicans filamentation. For in vivo study, Galleria mellonella was used as an infection model to evaluate the effects of L. acidophilus on candidiasis by survival analysis, quantification of C. albicans CFU/mL, and histological analysis. The direct effects of L. acidophilus cells on C. albicans, as well as the indirect effects using only a Lactobacillus culture filtrate, were evaluated in both tests. The in vitro results showed that both L. acidophilus cells and filtrate were able to inhibit C. albicans biofilm formation and filamentation. In the in vivo study, injection of L. acidophilus into G. mellonella larvae infected with C. albicans increased the survival of these animals. Furthermore, the number of C. albicans CFU/mL recovered from the larval hemolymph was lower in the group inoculated with L. acidophilus compared to the control group. In conclusion, L. acidophilus ATCC 4356 inhibited in vitro biofilm formation by C. albicans and protected G. mellonella against experimental candidiasis in vivo.

Lactobacillus acidophilus ATCC 4356 inhibits biofilm formation by C. albicans and attenuates the experimental candidiasis in Galleria mellonella

PubMed Central

Vilela, Simone FG; Barbosa, Júnia O; Rossoni, Rodnei D; Santos, Jéssica D; Prata, Marcia CA; Anbinder, Ana Lia; Jorge, Antonio OC; Junqueira, Juliana C

2015-01-01

Probiotic strains of Lactobacillus have been studied for their inhibitory effects on Candida albicans. However, few studies have investigated the effect of these strains on biofilm formation, filamentation and C. albicans infection. The objective of this study was to evaluate the influence of Lactobacillus acidophilus ATCC 4356 on C. albicans ATCC 18804 using in vitro and in vivo models. In vitro analysis evaluated the effects of L. acidophilus on the biofilm formation and on the capacity of C. albicans filamentation. For in vivo study, Galleria mellonella was used as an infection model to evaluate the effects of L. acidophilus on candidiasis by survival analysis, quantification of C. albicans CFU/mL, and histological analysis. The direct effects of L. acidophilus cells on C. albicans, as well as the indirect effects using only a Lactobacillus culture filtrate, were evaluated in both tests. The in vitro results showed that both L. acidophilus cells and filtrate were able to inhibit C. albicans biofilm formation and filamentation. In the in vivo study, injection of L. acidophilus into G. mellonella larvae infected with C. albicans increased the survival of these animals. Furthermore, the number of C. albicans CFU/mL recovered from the larval hemolymph was lower in the group inoculated with L. acidophilus compared to the control group. In conclusion, L. acidophilus ATCC 4356 inhibited in vitro biofilm formation by C. albicans and protected G. mellonella against experimental candidiasis in vivo. PMID:25654408

Removal of Salmonella Enteritidis from commercial unpasteurized liquid egg white using pilot scale cross flow tangential microfiltration.

PubMed

Mukhopadhyay, Sudarsan; Tomasula, Peggy M; Luchansky, John B; Porto-Fett, Anna; Call, Jeffrey E

2010-09-01

Effectiveness of a cross flow microfiltration (MF) process for removal of a cocktail of Salmonella enterica serovar Enteritidis species from commercial unpasteurized liquid egg white (LEW) from a local egg breaking plant, while maintaining its functional properties was evaluated. To facilitate MF, LEW was wedge screened, homogenized and then diluted (1:2 w/w) with distilled water containing 0.5% sodium chloride. Diluted unpasteurized LEW was inoculated with five strains of S. Enteritidis (ATCC 4931, ATCC BAA-708, ATCC 49215, ATCC 49218, and ATCC BAA-1045) to a level of approximately 10(7)CFU/mL of LEW and microfiltered using a ceramic membrane. Process parameters influencing egg white functional properties and pathogen removal efficiency were evaluated. Average permeates flux increased by almost 126% when pH of LEW was adjusted from pH 8 to pH 7 at 25 degrees C. Microbial removal efficiency was at least, on average, 6.8Log(10)CFU/mL (limit of detection < or =0.5Log(10)CFU/mL). Functional property analysis indicated that the MF process did not alter the foaming power of LEW. Published by Elsevier B.V.

[Contribution of blue-green pigments to hemolytic activity of Pseudomonas aeruginosa cultural fluid].

PubMed

Pyzh, A É; Nikandrov, V N

2011-01-01

To assess the contribution of blue-green pigments of Pseudomonas aeruginosa to hemolytic activity of its cultural fluid. MATERIALS AND METHODS. Eight hospital strains and reference strain ATCC 15442 were used. Growth dynamics of strains as well as features of accumulation of hemolytic and phospholipase activity were studied. Purified samples of pyoverdin and pyocyanin were extracted by gel-chromatography and chloroform extraction methods. Hemolytic and lecitinase activities of the samples as well as effect of active oxygen scavengers and chelating agents on these activities were studied. Dynamics of accumulation of hemolytic activity significantly differed from that of phospholipase activity when strains were grown in liquid medium. Chromatographic separation of the pigments from cultural fluid supernatants sharply reduced its hemolytic activity. Purified samples of pyoverdin and pyocyanin were capable to lyse erythrocytes and chicken egg lecitin. These characteristics of the pigments were inhibited by nitroblue tetrazolium and sensitive to chelating agents. Conclusion. Pyoverdin and pyocyanin of pathogenic strains of P. aeruginosa are capable to lyse erythrocytes and suspension of purified chicken egg lecitin, they contribute to total hemolytic activity of pathogenic strains of Pseudomonas, which is not determined only by phospholipase C produced by microorganism. Lytic activity of the pigments is blocked by nitroblue tetrazolium and susceptible to some chelating agents. Apparently, this activity is mediated by superoxide radical and determined by presence of metals with transient valence in pigments' molecules.

The inhibitory effects of wine phenolics on lysozyme activity against lactic acid bacteria.

PubMed

Guzzo, F; Cappello, M S; Azzolini, M; Tosi, E; Zapparoli, G

2011-08-15

The lysozyme of hen's egg white is used in winemaking to control spontaneous lactic acid bacteria (LAB). A total of eight LAB strains, isolated from grape must and wine, were used to assess the inhibitory effects of wine phenolics on lysozyme activity. The presence of phenolics, extracted from grape pomace, in growth medium reduced the mortality rate due to the lysozyme activity. This effect was especially clear in the case of strains belonging to Lactobacillus uvarum, Pediococcus parvulus and Oenococccus oeni, which are more sensitive to lysozyme than L. plantarum and L. hilgardii strains. Cell lysis assays carried out on four strains sensitive to lysozyme and Micrococcus lysodeikticus ATCC 4698, used as a reference strain, confirmed the inhibition of grape pomace phenolics on the muramidase. There was no interference from non-flavonoids, flavanols and flavonol compounds, when they were tested individually, on the lysozyme activity against the strains. Anthocyanins extracted from grape skins slightly inhibited the activity only against M. lysodeikticus. However, proanthocyanidins extracted from seed berries, strongly inhibited the lysozyme. In this extract, dimers were the predominant oligomers of flavan-3-ol. The study demonstrated that the effectiveness of lysozyme against LAB in red winemaking is related to the amount of low molecular weight proanthocyanidins that are released when the grapes are macerating. Copyright © 2011 Elsevier B.V. All rights reserved.

In Vitro Anti-Candida Activity of Lidocaine and Nitroglycerin: Alone and Combined

PubMed Central

Palmeira-de-Oliveira, Ana; Ramos, Ana Rita; Gaspar, Carlos; Palmeira-de-Oliveira, Rita; Gouveia, Paula; Martinez-de-Oliveira, José

2012-01-01

The aim of this work was to study the anti-Candida activity of lidocaine and nitroglycerin alone and in combination. Ten Candida strains were included, corresponding to 1 collection type strain (ATCC 10231) and 9 clinical isolates: 4 C. albicans, 2 C. glabrata, 1 C. tropicalis, 1 C. krusei, and 1 C. parapsilosis. The CLSI reference M27-A3 micromethod was used to determine the anti-Candida activity of the drugs alone; minimal inhibitory and lethal concentrations were determined. The classic checkboard technique was used to determine the activity of combined drugs. Lidocaine fungicidal effect was dosedependent. Nitroglycerin exhibited a higher effect. The drugs combination resulted in a reduction of the inhibitory concentration, corresponding to an additive effect. In conclusion, both drugs exhibited an interesting anti-Candida activity. The combination of lidocaine with nitroglycerin was shown to have an additive effect against Candida spp., predicting the interest to include, in the future, these drugs in a new delivery system for the treatment of mucocutaneous candidosis. PMID:22675243

Outer membrane defect and stronger biofilm formation caused by inactivation of a gene encoding for heptosyltransferase I in Cronobacter sakazakii ATCC BAA-894.

PubMed

Wang, L; Hu, X; Tao, G; Wang, X

2012-05-01

To investigate the role of lipopolysaccharide (LPS) structure in the stability of outer membrane and the ability of biofilm formation in Cronobacter sakazakii. A C. sakazakii mutant strain LWW02 was constructed by inactivating the gene ESA_04107 encoding for heptosyltransferase I. LPS were purified from LWW02, and changes in their structure were confirmed by thin-layer chromatography and electrospray ionization mass spectrometry. Comparing with the wild-type strain BAA-894, slower growth, higher membrane permeability, higher surface hydrophobicity, stronger ability of autoaggregation and biofilm formation were observed for the mutant strain LWW02. The gene ESA_04107 encodes heptosyltransferase I in C. sakazakii ATCC BAA-894. The cleavage of LPS in C. sakazakii could cause its outer membrane defects and increase its ability to form biofilms. The study is important for understanding the pathogenic mechanism and efficient control of C. sakazakii. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Exploring metabolic pathway reconstruction and genome-wide expression profiling in Lactobacillus reuteri to define functional probiotic features.

PubMed

Saulnier, Delphine M; Santos, Filipe; Roos, Stefan; Mistretta, Toni-Ann; Spinler, Jennifer K; Molenaar, Douwe; Teusink, Bas; Versalovic, James

2011-04-29

The genomes of four Lactobacillus reuteri strains isolated from human breast milk and the gastrointestinal tract have been recently sequenced as part of the Human Microbiome Project. Preliminary genome comparisons suggested that these strains belong to two different clades, previously shown to differ with respect to antimicrobial production, biofilm formation, and immunomodulation. To explain possible mechanisms of survival in the host and probiosis, we completed a detailed genomic comparison of two breast milk-derived isolates representative of each group: an established probiotic strain (L. reuteri ATCC 55730) and a strain with promising probiotic features (L. reuteri ATCC PTA 6475). Transcriptomes of L. reuteri strains in different growth phases were monitored using strain-specific microarrays, and compared using a pan-metabolic model representing all known metabolic reactions present in these strains. Both strains contained candidate genes involved in the survival and persistence in the gut such as mucus-binding proteins and enzymes scavenging reactive oxygen species. A large operon predicted to encode the synthesis of an exopolysaccharide was identified in strain 55730. Both strains were predicted to produce health-promoting factors, including antimicrobial agents and vitamins (folate, vitamin B(12)). Additionally, a complete pathway for thiamine biosynthesis was predicted in strain 55730 for the first time in this species. Candidate genes responsible for immunomodulatory properties of each strain were identified by transcriptomic comparisons. The production of bioactive metabolites by human-derived probiotics may be predicted using metabolic modeling and transcriptomics. Such strategies may facilitate selection and optimization of probiotics for health promotion, disease prevention and amelioration.

Anti-adherence potential of Enterococcus durans cells and its cell-free supernatant on plastic and stainless steel against foodborne pathogens.

PubMed

Amel, Ait Meddour; Farida, Bendali; Djamila, Sadoun

2015-07-01

It is demonstrated that numerous bacteria are able to attach to surfaces of equipment used for food handling or processing. In this study, a strain of Enterococcus durans, originally isolated from a milking machine surface, was firstly studied for its biofilm formation potential on plastic and stainless steel supports. The strain was found to be a biofilm producer either at 25, 30 or 37 °C on polystyrene microtitre plates, with a best adherence level observed at 25 °C. En. durans showed a strong adhesion to stainless steel AISI-304. Antibacterial and anti-adherence activities of En. durans were tested against four foodborne pathogens (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853 and Listeria innocua CLIP 74915) which were shown as biofilm producers on both plastic and stainless steel. En. durans cells and cell-free culture supernatant showed a significant (P < 0.05) inhibition potential of the pathogens either on solid media or in broth co-cultures. Characterization of the antibacterial substances indicated their proteinaceous nature which assigned them most probably to bacteriocins group.

Predicting and Modelling the Growth of Potentially Pathogenic Bacteria in Coalho Cheese.

PubMed

de Araújo, Valdenice Gomes; de Oliveira Arruda, Maria Digian; Dantas Duarte, Francisca Nayara; de Sousa, Janaína Maria Batista; da Costa Lima, Maiara; da Conceição, Maria Lúcia; Schaffner, Donald W; de Souza, Evandro Leite

2017-07-01

Coalho is a semihard medium- to high-moisture cheese produced in various states in the northeastern region of Brazil. This study was conducted to predict the growth kinetics (maximum growth rate, Grmax) of Escherichia coli, Listeria monocytogenes, Salmonella, and Staphylococcus aureus using the ComBase predictor with various combinations of temperature, pH, and water activity (a w ) in commercial Coalho cheese samples. The growth of two antibiotic-resistant derivative strains of L. monocytogenes (parental strains ATCC 19115 and ATCC 7644) and S. aureus (parental strains ATCC 13565 and ATCC 19095) was measured in commercial Coalho cheese samples during 14 days of storage as a function of the initial contamination level (3 and 5 log CFU/g) and storage temperature (7.5 and 12°C). The highest Grmax values predicted by ComBase under the various conditions of temperature, pH, and a w were for L. monocytogenes (0.006 to 0.065 log CFU/g/h) and S. aureus (0.003 to 0.048 log CFU/g/h). The Grmax values predicted by ComBase for E. coli and Salmonella were 0.007 to 0.026 and 0.008 to 0.041 log CFU/g/h, respectively. An experimental challenge in Coalho cheese revealed that the populations of all tested antibiotic-resistant derivative strains of L. monocytogenes and S. aureus increased (>0.5 log CFU/g) by day 14 of storage at 7.5 or 12°C. L. monocytogenes and S. aureus had higher Grmax values in cheese samples stored at 12°C than those stored at 7.5°C. The ComBase growth predictions under the temperature, pH, and a w conditions in commercial Coalho cheese samples were generally fail-safe for predicting the growth of L. monocytogenes and S. aureus in the actual product. These results indicate that Coalho cheese has pH and a w characteristics that allow the growth of E. coli, L. monocytogenes, Salmonella, and S. aureus. These cheeses are typically stored at temperatures that do not prevent the growth of these bacteria.

Porcine reproductive and respiratory syndrome virus: morphological, biochemical and serological characteristics of Quebec isolates associated with acute and chronic outbreaks of porcine reproductive and respiratory syndrome.

PubMed Central

Mardassi, H; Athanassious, R; Mounir, S; Dea, S

1994-01-01

Cytolytic and noncytolytic strains of the porcine reproductive and respiratory syndrome virus (PRRSV) were isolated in primary cultures of porcine alveolar macrophages (PAM) from lung homogenates of stillborn fetuses or blood samples of dyspneic piglets collected from Quebec pig farms having experienced acute or chronic outbreaks of PRRS. Serological identification of the virus was confirmed by indirect immunofluorescence and indirect protein A-gold immunoelectron microscopy using reference antiserum prepared from experimentally-infected specific pathogen free (SPF) piglets and monoclonal antibodies (MoAbs) directed against the p15 nucleocapsid (N) protein of the reference ATCC-VR2332 isolate. Intracytoplasmic enveloped viral particles that tended to accumulate into cytoplasmic vesicles were observed in the infected PAM; no budding was demonstrated at the level of the cytoplasmic membrane. The extracellular virions appeared as pleomorphic but mostly spherical enveloped particles, 50-72 nm in diameter (averaged diameter of 50 particles was 58.3 nm), with an isometric core about 25-30 nm. Buoyant density of the virus in CsCL density gradients was estimated to 1.18-1.20 g/mL. No hemagglutinating activity was demonstrated. Analysis of semipurified virions of isolate IAF-exp91 by radioimmunoprecipitation (RIPA) and Western immunoblotting experiments, using reference rabbit and porcine hyperimmune sera, revealed four major viral proteins, a predominant 15 kD N protein and three other proteins with predicted M(r_ of 19, 26 and 42 kD. Progeny viral particles produced in PRRSV-infected PAM in the presence of tunicamycin lacked the 42 kD protein, thus confirming its N-glycosylated nature. Immunoprecipitation experiments using the anti-ATCC-VR2332 MoAbs confirmed the close antigenic relationships between Quebec and American reference isolates of PRRSV. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:8143254

The identification of genes specific to Prevotella intermedia and Prevotella nigrescens using genomic subtractive hybridization.

PubMed

Masakiyo, Yoshiaki; Yoshida, Akihiro; Shintani, Yasuyuki; Takahashi, Yusuke; Ansai, Toshihiro; Takehara, Tadamichi

2010-06-01

Prevotella intermedia and Prevotella nigrescens, which are often isolated from periodontal sites, were once considered two different genotypes of P. intermedia. Although the genomic sequence of P. intermedia was determined recently, little is known about the genetic differences between P. intermedia and P. nigrescens. The subtractive hybridization technique is a powerful method for generating a set of DNA fragments differing between two closely related bacterial strains or species. We used subtractive hybridization to identify the DNA regions specific to P. intermedia ATCC 25611 and P. nigrescens ATCC 25261. Using this method, four P. intermedia ATCC 25611-specific and three P. nigrescens ATCC 25261-specific regions were determined. From the species-specific regions, insertion sequence (IS) elements were isolated for P. intermedia. IS elements play an important role in the pathogenicity of bacteria. For the P. intermedia-specific regions, the genes adenine-specific DNA-methyltransferase and 8-amino-7-oxononanoate synthase were isolated. The P. nigrescens-specific region contained a Flavobacterium psychrophilum SprA homologue, a cell-surface protein involved in gliding motility, Prevotella melaninogenica ATCC 25845 glutathione peroxide, and Porphyromonas gingivalis ATCC 33277 leucyl-tRNA synthetase. The results demonstrate that the subtractive hybridization technique was useful for distinguishing between the two closely related species. Furthermore, this technique will contribute to our understanding of the virulence of these species. 2009 Elsevier Ltd. All rights reserved.

Antimicrobial Potential of Endophytic Fungi Derived from Three Seagrass Species: Cymodocea serrulata, Halophila ovalis and Thalassia hemprichii

PubMed Central

Supaphon, Preuttiporn; Phongpaichit, Souwalak; Rukachaisirikul, Vatcharin; Sakayaroj, Jariya

2013-01-01

Endophytic fungi from three commonly found seagrasses in southern Thailand were explored for their ability to produce antimicrobial metabolites. One hundred and sixty endophytic fungi derived from Cymodocea serrulata (Family Cymodoceaceae), Halophila ovalis and Thalassia hemprichii (Family Hydrocharitaceae) were screened for production of antimicrobial compounds by a colorimetric broth microdilution test against ten human pathogenic microorganisms including Staphylococcus aureus ATCC 25923, a clinical isolate of methicillin-resistant S. aureus, Escherichia coli ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 90028 and NCPF 3153, Cryptococcus neoformans ATCC 90112 and ATCC 90113 and clinical isolates of Microsporum gypseum and Penicillium marneffei . Sixty-nine percent of the isolates exhibited antimicrobial activity against at least one test strain. Antifungal activity was more pronounced than antibacterial activity. Among the active fungi, seven isolates including Hypocreales sp. PSU-ES26 from C . serrulata , Trichoderma spp. PSU-ES8 and PSU-ES38 from H . ovalis , and Penicillium sp. PSU-ES43, Fusarium sp. PSU-ES73, Stephanonectria sp. PSU-ES172 and an unidentified endophyte PSU-ES190 from T . hemprichii exhibited strong antimicrobial activity against human pathogens with minimum inhibitory concentrations (MIC) of less than 10 µg/ml. The inhibitory extracts at concentrations of 4 times their MIC destroyed the targeted cells as observed by scanning electron microscopy. These results showed the antimicrobial potential of extracts from endophytic fungi from seagrasses. PMID:23977310

Antimicrobial potential of endophytic fungi derived from three seagrass species: Cymodocea serrulata, Halophila ovalis and Thalassia hemprichii.

PubMed

Supaphon, Preuttiporn; Phongpaichit, Souwalak; Rukachaisirikul, Vatcharin; Sakayaroj, Jariya

2013-01-01

Endophytic fungi from three commonly found seagrasses in southern Thailand were explored for their ability to produce antimicrobial metabolites. One hundred and sixty endophytic fungi derived from Cymodoceaserrulata (Family Cymodoceaceae), Halophilaovalis and Thalassiahemprichii (Family Hydrocharitaceae) were screened for production of antimicrobial compounds by a colorimetric broth microdilution test against ten human pathogenic microorganisms including Staphylococcus aureus ATCC 25923, a clinical isolate of methicillin-resistant S. aureus, Escherichia coli ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 90028 and NCPF 3153, Cryptococcus neoformans ATCC 90112 and ATCC 90113 and clinical isolates of Microsporumgypseum and Penicilliummarneffei. Sixty-nine percent of the isolates exhibited antimicrobial activity against at least one test strain. Antifungal activity was more pronounced than antibacterial activity. Among the active fungi, seven isolates including Hypocreales sp. PSU-ES26 from C. serrulata, Trichoderma spp. PSU-ES8 and PSU-ES38 from H. ovalis, and Penicillium sp. PSU-ES43, Fusarium sp. PSU-ES73, Stephanonectria sp. PSU-ES172 and an unidentified endophyte PSU-ES190 from T. hemprichii exhibited strong antimicrobial activity against human pathogens with minimum inhibitory concentrations (MIC) of less than 10 µg/ml. The inhibitory extracts at concentrations of 4 times their MIC destroyed the targeted cells as observed by scanning electron microscopy. These results showed the antimicrobial potential of extracts from endophytic fungi from seagrasses.

Evolutionarily informative strain-typing for Beauveria bassiana: multilocus haplotype stability and a genetic context for the mycoinsecticide GHA

USDA-ARS?s Scientific Manuscript database

Beauveria bassiana strain GHA (ARSEF3620, ATCC74250), the active component of mycoinsecticide formulations BotaniGard® and Mycotrol® (Certis, Columbia, MD), is a leading fungal biocontrol agent used against pest insects. Due to its pathogenicity and virulence toward diverse insect taxa, GHA is often...

Complete genome sequence of the larval shellfish pathogen Vibrio Tubiashii type strain ATCC 19109

USDA-ARS?s Scientific Manuscript database

Vibrio tubiashii is a larval shellfish pathogen. Here we report the first closed genome sequence for this species (American Type Culture Collection type strain 19109), which has two chromosomes (3,294,490 and 1,766,582 bp), two megaplasmids (251,408 and 122,808 bp) and two plasmids (57,076 and 47,9...

Tyrosine decarboxylase activity of enterococci grown in media with different nutritional potential: tyramine and 2-phenylethylamine accumulation and tyrDC gene expression.

PubMed

Bargossi, Eleonora; Tabanelli, Giulia; Montanari, Chiara; Lanciotti, Rosalba; Gatto, Veronica; Gardini, Fausto; Torriani, Sandra

2015-01-01

The ability to accumulate tyramine and 2-phenylethylamine by two strains of Enterococcus faecalis and two strains Enterococcus faecium was evaluated in two cultural media added or not with tyrosine. All the enterococcal strains possessed a tyrosine decarboxylase (tyrDC) which determined tyramine accumulation in all the conditions tested, independently on the addition of high concentration of free tyrosine. Enterococci differed in rate and level of biogenic amines accumulation. E. faecalis EF37 and E. faecium FC12 produced tyramine in high amount since the exponential growth phase, while 2-phenylethylamine was accumulated when tyrosine was depleted. E. faecium FC12 and E. faecalis ATCC 29212 showed a slower tyraminogenic activity which took place mainly in the stationary phase up to 72 h of incubation. Moreover, E. faecalis ATCC 29212 produced 2-phenylethylamine only in the media without tyrosine added. In BHI added or not with tyrosine the tyrDC gene expression level differed considerably depending on the strains and the growth phase. In particular, the tyrDC gene expression was high during the exponential phase in rich medium for all the strains and subsequently decreased except for E. faecium FC12. Even if tyrDC presence is common among enterococci, this study underlines the extremely variable decarboxylating potential of strains belonging to the same species, suggesting strain-dependent implications in food safety.

Chromobacterium haemolyticum sp. nov., a strongly haemolytic species.

PubMed

Han, Xiang Y; Han, Faye S; Segal, Jonathan

2008-06-01

A Gram-negative bacterium, strain MDA0585(T), isolated from a sputum culture, was characterized by a polyphasic approach. The 16S rRNA gene and a conserved portion of the DNA gyrase A gene were sequenced and analysed phylogenetically. Strain MDA0585(T) showed the closest relationships with Chromobacterium violaceum ATCC 12472(T) and Chromobacterium subtsugae PRAA4-1(T) (96.1 % and 96.3 % 16S rRNA gene sequence similarity, respectively). The cellular fatty acids of strain MDA0585(T) consisted mainly of C(16 : 0), C(16 : 1)omega7c and C(16 : 1)omega6c (summed feature 3) and C(18 : 1)omega7c and C(18 : 1)omega6c (summed feature 8), a profile that was similar to, but distinguishable from, those of C. violaceum ATCC 12472(T) and C. subtsugae PRAA4-1(T). In culture, strain MDA0585(T) differed from C. violaceum and C. subtsugae in several ways: lack of violet pigmentation, the ability to haemolyse sheep blood, differences in several biochemical reactions and higher resistance to antibiotics. The culture supernatant of strain MDA0585(T) also caused remarkable haemolysis of human erythrocytes. These results suggest that strain MDA0585(T) represents a novel species within the genus Chromobacterium, for which the name Chromobacterium haemolyticum sp. nov. is proposed. The type strain is MDA0585(T) (=CCUG 53230(T)=JCM 14163(T)=DSM 19808(T)).

Proposal of Sphingomonas suberifaciens (van Bruggen, Jochimsen and Brown 1990) comb. nov., sphingomonas natatoria (Sly 1985) comb. nov., Sphingomonas ursincola (Yurkov et al. 1997) comb. nov., and emendation of the genus Sphingomonas.

PubMed

Yabuuchi, E; Kosako, Y; Naka, T; Suzuki, S; Yano, I

1999-01-01

Based on the results of a phylogenetic analysis of 16S rRNA and the presence of sphingoglycolipid in cellular lipids of the type strains, transfer of "Rhizomonas" suberifaciens, Blastomonas natatoria and Erythromonas ursincola to the genus Sphingomonas as Sphingomonas suberifaciens (van Bruggen et al 1990) comb. nov., Sphingomonas natatoria (Sly 1985) comb. nov., and Sphingomonas ursincola (Yurkov et al 1997) comb. nov. are herein proposed together with the emendation of genus Sphingomonas. The type strain of S. suberifaciens is van Bruggen Cal=ATCC 49382=NCPPB 3629=IFO 15211=JCM 8521, that of S. natatoria is ATCC 35951 =DSM 3183=NCIMB 12085=JCM10396, and that of S. ursincola is DSM 9006= KR-99.

Inhibition and inactivation of Salmonella typhimurium biofilms from polystyrene and stainless steel surfaces by essential oils and phenolic constituent carvacrol.

PubMed

Soni, Kamlesh A; Oladunjoye, Ademola; Nannapaneni, Ramakrishna; Schilling, M Wes; Silva, Juan L; Mikel, Benjy; Bailey, R Hartford

2013-02-01

Persistence of Salmonella biofilms within food processing environments is an important source of Salmonella contamination in the food chain. In this study, essential oils of thyme and oregano and their antimicrobial phenolic constituent carvacrol were evaluated for their ability to inhibit biofilm formation and inactivate preformed Salmonella biofilms. A crystal violet staining assay and CFU measurements were utilized to quantify biofilm cell mass, with evaluating factors such as strain variation, essential oil type, their concentrations, exposure time, as well as biofilm formation surface. Of the three Salmonella strains, Salmonella Typhimurium ATCC 23564 and Salmonella Typhimurium ATCC 19585 produced stronger biofilms than Salmonella Typhimurium ATCC 14028. Biofilm formation by different Salmonella strains was 1.5- to 2-fold higher at 22°C than at 30 or 37°C. The presence of nonbiocidal concentrations of thyme oil, oregano oil, and phenolic carvacrol at 0.006 to 0.012% suppressed Salmonella spp. biofilm formation 2- to 4-fold, but could not completely eliminate biofilm formation. There was high correlation in terms of biofilm inactivation, as determined by the crystal violet-stained optical density (at a 562-nm wavelength) readings and the viable CFU counts. Reduction of biofilm cell mass was dependent on antimicrobial concentration. A minimum concentration of 0.05 to 0.1% of these antimicrobial agents was needed to reduce a 7-log CFU biofilm mass to a nondetectable level on both polystyrene and stainless steel surfaces within 1 h of exposure time.

Metabolic engineering of Clostridium tyrobutyricum for enhanced butyric acid production with high butyrate/acetate ratio.

PubMed

Suo, Yukai; Ren, Mengmeng; Yang, Xitong; Liao, Zhengping; Fu, Hongxin; Wang, Jufang

2018-05-01

Butyric acid fermentation by Clostridium couples with the synthesis of acetic acid. But the presence of acetic acid reduces butyric acid yield and increases separation and purification costs of butyric acid. Hence, enhancing the butyrate/acetate ratio is important for economical butyric acid production. This study indicated that enhancing the acetyl-CoA to butyrate flux by overexpression of both the butyryl-CoA/acetate CoA transferase (cat1) and crotonase (crt) genes in C. tyrobutyricum could significantly reduce acetic acid concentration. Fed-batch fermentation of ATCC 25755/cat1 + crt resulted in increased butyrate/acetate ratio of 15.76 g/g, which was 2.24-fold higher than that of the wild-type strain. Furthermore, in order to simultaneously increase the butyrate/acetate ratio, butyric acid concentration and productivity, the recombinant strain ATCC 25755/ppcc (co-expression of 6-phosphofructokinase (pfkA) gene, pyruvate kinase (pykA) gene, cat1, and crt) was constructed. Consequently, ATCC 25755/ppcc produced more butyric acid (46.8 vs. 35.0 g/L) with a higher productivity (0.83 vs. 0.49 g/L·h) and butyrate/acetate ratio (13.22 vs. 7.22 g/g) as compared with the wild-type strain in batch fermentation using high glucose concentration (120 g/L). This study demonstrates that enhancing the acetyl-CoA to butyrate flux is an effective way to reduce acetic acid production and increase butyrate/acetate ratio.

Changes in growth and survival of Bifidobacterium by coculture with Propionibacterium in soy milk, cow's milk, and modified MRS medium.

PubMed

Wu, Qian Qian; You, Hyun Ju; Ahn, Hyung Jin; Kwon, Bin; Ji, Geun Eog

2012-06-15

Bifidobacterium adolescentis Int57 (Int57) and Propionibacterium freudenreichii subsp. shermanii ATCC 13673 (ATCC 13673) were grown either in coculture or as pure cultures in different media, such as cow's milk, soybean milk, and modified MRS medium. The viable cell counts of bacteria, changes in pH, concentrations of organic acids, and contents of various sugars were analyzed during incubation up to 7days. In soy milk, the survival of cocultured Int57 was six times higher than the monocultured cells, and ATCC 13673 cocultured with Int57 consumed 69.4% of lactic acid produced by Int57 at the end of fermentation. In cow's milk, coculture with ATCC 13673 increased the growth of Int57 from 24h until 120h by approximately tenfold and did not affect the survival of Int57 cells. After 96h of fermentation of modified MRS, the survival of ATCC 13673 cells cocultured with Int57 increased by 3.2- to 7.4-folds as compared with ATCC 13673 monoculture, whereas the growth of Int57 cells was unaffected. The growth and metabolic patterns of two strains during coculture showed noticeable differences between food grade media and laboratory media. The consumption of stachyose in soy milk during coculture of Int57 with ATCC 13673 was increased by more than twice compared with Int57 monoculture, and completed within 24h. The combinational use of Bifidobacterium and Propionibacterium could be applied to the development of fermented milk or soy milk products. Copyright © 2012 Elsevier B.V. All rights reserved.

Involvement of Clostridium botulinum ATCC 3502 Sigma Factor K in Early-Stage Sporulation

PubMed Central

Kirk, David G.; Dahlsten, Elias; Zhang, Zhen; Korkeala, Hannu

2012-01-01

A key survival mechanism of Clostridium botulinum, the notorious neurotoxic food pathogen, is the ability to form heat-resistant spores. While the genetic mechanisms of sporulation are well understood in the model organism Bacillus subtilis, nothing is known about these mechanisms in C. botulinum. Using the ClosTron gene-knockout tool, sigK, encoding late-stage (stage IV) sporulation sigma factor K in B. subtilis, was disrupted in C. botulinum ATCC 3502 to produce two different mutants with distinct insertion sites and orientations. Both mutants were unable to form spores, and their elongated cell morphology suggested that the sporulation pathway was blocked at an early stage. In contrast, sigK-complemented mutants sporulated successfully. Quantitative real-time PCR analysis of sigK in the parent strain revealed expression at the late log growth phase in the parent strain. Analysis of spo0A, encoding the sporulation master switch, in the sigK mutant and the parent showed significantly reduced relative levels of spo0A expression in the sigK mutant compared to the parent strain. Similarly, sigF showed significantly lower relative transcription levels in the sigK mutant than the parent strain, suggesting that the sporulation pathway was blocked in the sigK mutant at an early stage. We conclude that σK is essential for early-stage sporulation in C. botulinum ATCC 3502, rather than being involved in late-stage sporulation, as reported for the sporulation model organism B. subtilis. Understanding the sporulation mechanism of C. botulinum provides keys to control the public health risks that the spores of this dangerous pathogen cause through foods. PMID:22544236

Antimicrobial Activity of Intraurethrally Administered Probiotic Lactobacillus casei in a Murine Model of Escherichia coli Urinary Tract Infection

PubMed Central

Asahara, Takashi; Nomoto, Koji; Watanuki, Masaaki; Yokokura, Teruo

2001-01-01

The antimicrobial activity of the intraurethrally administered probiotic Lactobacillus casei strain Shirota against Escherichia coli in a murine urinary tract infection (UTI) model was examined. UTI was induced by intraurethral administration of Escherichia coli strain HU-1 (a clinical isolate from a UTI patient, positive for type 1 and P fimbriae), at a dose of 1 × 106 to 2 × 106 CFU in 20 μl of saline, into a C3H/HeN mouse bladder which had been traumatized with 0.1 N HCl followed immediately by neutralization with 0.1 N NaOH 24 h before the challenge infection. Chronic infection with the pathogen at 106 CFU in the urinary tract (bladder and kidneys) was maintained for more than 3 weeks after the challenge, and the number of polymorphonuclear leukocytes and myeloperoxidase activity in the urine were markedly elevated during the infection period. A single administration of L. casei Shirota at a dose of 108 CFU 24 h before the challenge infection dramatically inhibited E. coli growth and inflammatory responses in the urinary tract. Multiple daily treatments with L. casei Shirota during the postinfection period also showed antimicrobial activity in this UTI model. A heat-killed preparation of L. casei Shirota exerted significant antimicrobial effects not only with a single pretreatment (100 μg/mouse) but also with multiple daily treatments during the postinfection period. The other Lactobacillus strains tested, i.e., L. fermentum ATCC 14931T, L. jensenii ATCC 25258T, L. plantarum ATCC 14917T, and L. reuteri JCM 1112T, had no significant antimicrobial activity. Taken together, these results suggest that the probiotic L. casei strain Shirota is a potent therapeutic agent for UTI. PMID:11353622

Antimicrobial activity of intraurethrally administered probiotic Lactobacillus casei in a murine model of Escherichia coli urinary tract infection.

PubMed

Asahara, T; Nomoto, K; Watanuki, M; Yokokura, T

2001-06-01

The antimicrobial activity of the intraurethrally administered probiotic Lactobacillus casei strain Shirota against Escherichia coli in a murine urinary tract infection (UTI) model was examined. UTI was induced by intraurethral administration of Escherichia coli strain HU-1 (a clinical isolate from a UTI patient, positive for type 1 and P fimbriae), at a dose of 1 x 10(6) to 2 x 10(6) CFU in 20 microl of saline, into a C3H/HeN mouse bladder which had been traumatized with 0.1 N HCl followed immediately by neutralization with 0.1 N NaOH 24 h before the challenge infection. Chronic infection with the pathogen at 10(6) CFU in the urinary tract (bladder and kidneys) was maintained for more than 3 weeks after the challenge, and the number of polymorphonuclear leukocytes and myeloperoxidase activity in the urine were markedly elevated during the infection period. A single administration of L. casei Shirota at a dose of 10(8) CFU 24 h before the challenge infection dramatically inhibited E. coli growth and inflammatory responses in the urinary tract. Multiple daily treatments with L. casei Shirota during the postinfection period also showed antimicrobial activity in this UTI model. A heat-killed preparation of L. casei Shirota exerted significant antimicrobial effects not only with a single pretreatment (100 microg/mouse) but also with multiple daily treatments during the postinfection period. The other Lactobacillus strains tested, i.e., L. fermentum ATCC 14931(T), L. jensenii ATCC 25258(T), L. plantarum ATCC 14917(T), and L. reuteri JCM 1112(T), had no significant antimicrobial activity. Taken together, these results suggest that the probiotic L. casei strain Shirota is a potent therapeutic agent for UTI.

Involvement of Clostridium botulinum ATCC 3502 sigma factor K in early-stage sporulation.

PubMed

Kirk, David G; Dahlsten, Elias; Zhang, Zhen; Korkeala, Hannu; Lindström, Miia

2012-07-01

A key survival mechanism of Clostridium botulinum, the notorious neurotoxic food pathogen, is the ability to form heat-resistant spores. While the genetic mechanisms of sporulation are well understood in the model organism Bacillus subtilis, nothing is known about these mechanisms in C. botulinum. Using the ClosTron gene-knockout tool, sigK, encoding late-stage (stage IV) sporulation sigma factor K in B. subtilis, was disrupted in C. botulinum ATCC 3502 to produce two different mutants with distinct insertion sites and orientations. Both mutants were unable to form spores, and their elongated cell morphology suggested that the sporulation pathway was blocked at an early stage. In contrast, sigK-complemented mutants sporulated successfully. Quantitative real-time PCR analysis of sigK in the parent strain revealed expression at the late log growth phase in the parent strain. Analysis of spo0A, encoding the sporulation master switch, in the sigK mutant and the parent showed significantly reduced relative levels of spo0A expression in the sigK mutant compared to the parent strain. Similarly, sigF showed significantly lower relative transcription levels in the sigK mutant than the parent strain, suggesting that the sporulation pathway was blocked in the sigK mutant at an early stage. We conclude that σ(K) is essential for early-stage sporulation in C. botulinum ATCC 3502, rather than being involved in late-stage sporulation, as reported for the sporulation model organism B. subtilis. Understanding the sporulation mechanism of C. botulinum provides keys to control the public health risks that the spores of this dangerous pathogen cause through foods.

Characterization of two nisin-producing Lactococcus lactis subsp. lactis strains isolated from a commercial sauerkraut fermentation.

PubMed Central

Harris, L J; Fleming, H P; Klaenhammer, T R

1992-01-01

Two Lactococcus lactis subsp. lactis strains, NCK400 and LJH80, isolated from a commercial sauerkraut fermentation were shown to produce nisin. LJH80 was morphologically unstable and gave rise to two stable, nisin-producing (Nip+) derivatives, NCK318-2 and NCK318-3. NCK400 and derivatives of LJH80 exhibited identical morphological and metabolic characteristics, but could be distinguished on the basis of plasmid profiles and genomic hybridization patterns to a DNA probe specific for the iso-ISS1 element, IS946. NCK318-2 and NCK318-3 harbored two and three plasmids, respectively, which hybridized with IS946. Plasmid DNA was not detected in NCK400, and DNA from this strain failed to hybridize with IS946. Despite the absence of detectable plasmid DNA in NCK400, nisin-negative derivatives (NCK402 and NCK403) were isolated after repeated transfer in broth at 37 degrees C. Nisin-negative derivatives concurrently lost the ability to ferment sucrose and became sensitive to nisin. A 4-kbp HindIII fragment containing the structural gene for nisin (spaN), cloned from L. lactis subsp. lactis ATCC 11454, was used to probe genomic DNA of NCK318-2, NCK318-3, NCK400, and NCK402 digested with EcoRI or HindIII. The spaN probe hybridized to an 8.8-kbp EcoRI fragment and a 10-kbp HindIII fragment in the Nip+ sauerkraut isolates, but did not hybridize to the Nip- derivative, NCK402. A different hybridization pattern was observed when the same probe was used against Nip+ L. lactis subsp. lactis ATCC 11454 and ATCC 7962. These phenotypic and genetic data confirmed that unique Nip+ L. lactis subsp. lactis strains were isolated from fermenting sauerkraut. Images PMID:1622214

Use of Natural Transformation To Establish an Easy Knockout Method in Riemerella anatipestifer.

PubMed

Liu, MaFeng; Zhang, Li; Huang, Li; Biville, Francis; Zhu, DeKang; Wang, MingShu; Jia, RenYong; Chen, Shun; Sun, KunFeng; Yang, Qiao; Wu, Ying; Chen, XiaoYue; Cheng, AnChun

2017-05-01

Riemerella anatipestifer is a member of the family Flavobacteriaceae and a major causative agent of duck serositis. Little is known about its genetics and pathogenesis. Several bacteria are competent for natural transformation; however, whether R. anatipestifer is also competent for natural transformation has not been investigated. Here, we showed that R. anatipestifer strain ATCC 11845 can uptake the chromosomal DNA of R. anatipestifer strain RA-CH-1 in all growth phases. Subsequently, a natural transformation-based knockout method was established for R. anatipestifer ATCC 11845. Targeted mutagenesis gave transformation frequencies of ∼10 -5 transformants. Competition assay experiments showed that R. anatipestifer ATCC 11845 preferentially took up its own DNA rather than heterogeneous DNA, such as Escherichia coli DNA. Transformation was less efficient with the shuttle plasmid pLMF03 (transformation frequencies of ∼10 -9 transformants). However, the efficiency of transformation was increased approximately 100-fold using pLMF03 derivatives containing R. anatipestifer DNA fragments (transformation frequencies of ∼10 -7 transformants). Finally, we found that the R. anatipestifer RA-CH-1 strain was also naturally transformable, suggesting that natural competence is widely applicable for this species. The findings described here provide important tools for the genetic manipulation of R. anatipestifer IMPORTANCE Riemerella anatipestifer is an important duck pathogen that belongs to the family Flavobacteriaceae At least 21 different serotypes have been identified. Genetic diversity has been demonstrated among these serotypes. The genetic and pathogenic mechanisms of R. anatipestifer remain largely unknown because no genetic tools are available for this bacterium. At present, natural transformation has been found in some bacteria but not in R. anatipestifer For the first time, we showed that natural transformation occurred in R. anatipestifer ATCC 11845 and R. anatipestifer RA-CH-1. Then, we established an easy gene knockout method in R. anatipestifer based on natural transformation. This information is important for further studies of the genetic diversity and pathogenesis in R. anatipestifer . Copyright © 2017 American Society for Microbiology.

Functional Features of TonB Energy Transduction Systems of Acinetobacter baumannii

PubMed Central

Zimbler, Daniel L.; Arivett, Brock A.; Beckett, Amber C.; Menke, Sharon M.

2013-01-01

Acinetobacter baumannii is an opportunistic pathogen that causes severe nosocomial infections. Strain ATCC 19606T utilizes the siderophore acinetobactin to acquire iron under iron-limiting conditions encountered in the host. Accordingly, the genome of this strain has three tonB genes encoding proteins for energy transduction functions needed for the active transport of nutrients, including iron, through the outer membrane. Phylogenetic analysis indicates that these tonB genes, which are present in the genomes of all sequenced A. baumannii strains, were acquired from different sources. Two of these genes occur as components of tonB-exbB-exbD operons and one as a monocistronic copy; all are actively transcribed in ATCC 19606T. The abilities of components of these TonB systems to complement the growth defect of Escherichia coli W3110 mutants KP1344 (tonB) and RA1051 (exbBD) under iron-chelated conditions further support the roles of these TonB systems in iron acquisition. Mutagenesis analysis of ATCC 19606T tonB1 (subscripted numbers represent different copies of genes or proteins) and tonB2 supports this hypothesis: their inactivation results in growth defects in iron-chelated media, without affecting acinetobactin biosynthesis or the production of the acinetobactin outer membrane receptor protein BauA. In vivo assays using Galleria mellonella show that each TonB protein is involved in, but not essential for, bacterial virulence in this infection model. Furthermore, we observed that TonB2 plays a role in the ability of bacteria to bind to fibronectin and to adhere to A549 cells by uncharacterized mechanisms. Taken together, these results indicate that A. baumannii ATCC 19606T produces three independent TonB proteins, which appear to provide the energy-transducing functions needed for iron acquisition and cellular processes that play a role in the virulence of this pathogen. PMID:23817614

Comparative genome analysis of rice-pathogenic Burkholderia provides insight into capacity to adapt to different environments and hosts.

PubMed

Seo, Young-Su; Lim, Jae Yun; Park, Jungwook; Kim, Sunyoung; Lee, Hyun-Hee; Cheong, Hoon; Kim, Sang-Mok; Moon, Jae Sun; Hwang, Ingyu

2015-05-06

In addition to human and animal diseases, bacteria of the genus Burkholderia can cause plant diseases. The representative species of rice-pathogenic Burkholderia are Burkholderia glumae, B. gladioli, and B. plantarii, which primarily cause grain rot, sheath rot, and seedling blight, respectively, resulting in severe reductions in rice production. Though Burkholderia rice pathogens cause problems in rice-growing countries, comprehensive studies of these rice-pathogenic species aiming to control Burkholderia-mediated diseases are only in the early stages. We first sequenced the complete genome of B. plantarii ATCC 43733T. Second, we conducted comparative analysis of the newly sequenced B. plantarii ATCC 43733T genome with eleven complete or draft genomes of B. glumae and B. gladioli strains. Furthermore, we compared the genome of three rice Burkholderia pathogens with those of other Burkholderia species such as those found in environmental habitats and those known as animal/human pathogens. These B. glumae, B. gladioli, and B. plantarii strains have unique genes involved in toxoflavin or tropolone toxin production and the clustered regularly interspaced short palindromic repeats (CRISPR)-mediated bacterial immune system. Although the genome of B. plantarii ATCC 43733T has many common features with those of B. glumae and B. gladioli, this B. plantarii strain has several unique features, including quorum sensing and CRISPR/CRISPR-associated protein (Cas) systems. The complete genome sequence of B. plantarii ATCC 43733T and publicly available genomes of B. glumae BGR1 and B. gladioli BSR3 enabled comprehensive comparative genome analyses among three rice-pathogenic Burkholderia species responsible for tissue rotting and seedling blight. Our results suggest that B. glumae has evolved rapidly, or has undergone rapid genome rearrangements or deletions, in response to the hosts. It also, clarifies the unique features of rice pathogenic Burkholderia species relative to other animal and human Burkholderia species.

ALLocator: an interactive web platform for the analysis of metabolomic LC-ESI-MS datasets, enabling semi-automated, user-revised compound annotation and mass isotopomer ratio analysis.

PubMed

Kessler, Nikolas; Walter, Frederik; Persicke, Marcus; Albaum, Stefan P; Kalinowski, Jörn; Goesmann, Alexander; Niehaus, Karsten; Nattkemper, Tim W

2014-01-01

Adduct formation, fragmentation events and matrix effects impose special challenges to the identification and quantitation of metabolites in LC-ESI-MS datasets. An important step in compound identification is the deconvolution of mass signals. During this processing step, peaks representing adducts, fragments, and isotopologues of the same analyte are allocated to a distinct group, in order to separate peaks from coeluting compounds. From these peak groups, neutral masses and pseudo spectra are derived and used for metabolite identification via mass decomposition and database matching. Quantitation of metabolites is hampered by matrix effects and nonlinear responses in LC-ESI-MS measurements. A common approach to correct for these effects is the addition of a U-13C-labeled internal standard and the calculation of mass isotopomer ratios for each metabolite. Here we present a new web-platform for the analysis of LC-ESI-MS experiments. ALLocator covers the workflow from raw data processing to metabolite identification and mass isotopomer ratio analysis. The integrated processing pipeline for spectra deconvolution "ALLocatorSD" generates pseudo spectra and automatically identifies peaks emerging from the U-13C-labeled internal standard. Information from the latter improves mass decomposition and annotation of neutral losses. ALLocator provides an interactive and dynamic interface to explore and enhance the results in depth. Pseudo spectra of identified metabolites can be stored in user- and method-specific reference lists that can be applied on succeeding datasets. The potential of the software is exemplified in an experiment, in which abundance fold-changes of metabolites of the l-arginine biosynthesis in C. glutamicum type strain ATCC 13032 and l-arginine producing strain ATCC 21831 are compared. Furthermore, the capability for detection and annotation of uncommon large neutral losses is shown by the identification of (γ-)glutamyl dipeptides in the same strains. ALLocator is available online at: https://allocator.cebitec.uni-bielefeld.de. A login is required, but freely available.

Comparative analysis of Staphylococcus epidermidis strains utilizing quantitative and cell surface shaving proteomics.

PubMed

Solis, Nestor; Cain, Joel A; Cordwell, Stuart J

2016-01-01

Staphylococcus epidermidis is an opportunistic pathogen that is an emerging risk factor in hospitals worldwide and is often difficult to eradicate as virulent strains produce a protective biofilm matrix. We utilized cell shaving proteomics to profile surface-exposed proteins from two fully genome sequenced S. epidermidis strains: the avirulent, non-biofilm forming ATCC12228 and the virulent, strongly adherent biofilm forming ATCC35984 (RP62A). A false positive control strategy was employed to calculate the probabilities of proteins being truly surface-exposed. A total of 78 surface-exposed proteins were identified, of which only 19 proteins were common to ATCC12228 and RP62A, and which thus represents the core surfaceome. S. epidermidis RP62A displayed additional proteins involved in biofilm formation (cell wall-associated Bhp and intercellular adhesion protein IcaB), surface antigenicity, peptidoglycan biosynthesis and antibiotic resistance. We concurrently profiled whole cell proteomes of the two strains using iTRAQ quantitation and LC-MS/MS. A total of 1610 proteins were confidently identified (representing 64% of the theoretical S. epidermidis proteome). One hundred and ninety one proteins were differentially abundant between strains. Proteins associated with RP62A were clustered into functions including Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-mediated defense, sulfate assimilation, antibiotic resistance and biofilm formation. Validation of the sulfate assimilation and cysteine/methionine biosynthesis pathways showed RP62A contained elevated levels (~25% increase) of methionine that are likely linked to biofilm formation. Cell shaving and quantitative proteomics identified proteins associated with a biofilm-forming, virulent strain of S. epidermidis (RP62A). These proteins show RP62A maintains an active CRISPR-mediated defense, as well as heightened antibiotic resistance in comparison to a non-virulent, non-biofilm forming strain. Increased abundances of sulfate assimilation proteins lead to elevated intracellular methionine. Proteins and their exposed peptides identified on the surface of S. epidermidis RP62A may be useful vaccine antigens in clinical settings if administered in at-risk patients prior to surgical implantations. Copyright © 2015 Elsevier B.V. All rights reserved.

Genetic relatedness of Legionella longbeachae isolates from human and environmental sources in Australia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lanser, J.A.; Doyle, R.; Sangster, N.

1990-09-01

The genetic relatedness of Legionella longbeachae isolated in Australia since 1987 was investigated by restriction fragment length polymorphism (RFLP) analysis and allozyme electrophoresis. Three radiolabeled probes were used in Southern hybridizations for the RFLP studies. They were Escherichia coli 16S and 23S rRNA and cloned fragments of L. longbeachae selected empirically from genomal banks in lambda and a cosmid. The legionellae included in the study comprised 11 Legionella longbeachae serogroup 1 organisms isolated form humans, 28 L. longbeachae serogroup 1 isolates from environmental sources, 3 L. longbeachae serogroup 2 environmental isolates. These were compared with the American Type Culture Collectionmore » reference strains of both serogroups and some other related Legionella species. Results of allozyme and RFLP analysis showed that all the isolates from humans and all but three of the environmental L. longbeachae serogroup 1 isolates were closely related. They were also closely related to L. longbeachae serogroup 1 ATCC 33462. There was wider variation among the three L. longbeachae serogroup 2 environmental isolates. One of these was closely related to L. longbeachae serogroup 2 ATCC 33484. RFLP studies with the rRNA probe provided the most discrimination among isolates but did not distinguish between the two serogroups.« less

Detection of hydrogen cyanide from oral anaerobes by cavity ring down spectroscopy

PubMed Central

Chen, Wen; Roslund, Kajsa; Fogarty, Christopher L.; Pussinen, Pirkko J.; Halonen, Lauri; Groop, Per-Henrik; Metsälä, Markus; Lehto, Markku

2016-01-01

Hydrogen cyanide (HCN) has been recognized as a potential biomarker for non-invasive diagnosis of Pseudomonas aeruginosa infection in the lung. However, the oral cavity is a dominant production site for exhaled HCN and this contribution can mask the HCN generated in the lung. It is thus important to understand the sources of HCN production in the oral cavity. By screening of oral anaerobes for HCN production, we observed that the genus of Porphyromonas, Prevotella and Fusobacterium generated low levels of HCN in vitro. This is the first study to show that oral anaerobes are capable of producing HCN in vitro. Further investigations were conducted on the species of P. gingivalis and we successfully detected HCN production (0.9–10.9 ppb) in the headspace of three P. gingivalis reference strains (ATCC 33277, W50 and OMG 434) and one clinical isolate. From P. gingivalis ATCC 33277 and W50, a strong correlation between HCN and CO2 concentrations (rs = 0.89, p < 0.001) was observed, indicating that the HCN production of P. gingivalis might be connected with the bacterial metabolic activity. These results indicate that our setup could be widely applied to the screening of in vitro HCN production by both aerobic and anaerobic bacteria. PMID:26940198

Detection of hydrogen cyanide from oral anaerobes by cavity ring down spectroscopy

NASA Astrophysics Data System (ADS)

Chen, Wen; Roslund, Kajsa; Fogarty, Christopher L.; Pussinen, Pirkko J.; Halonen, Lauri; Groop, Per-Henrik; Metsälä, Markus; Lehto, Markku

2016-03-01

Hydrogen cyanide (HCN) has been recognized as a potential biomarker for non-invasive diagnosis of Pseudomonas aeruginosa infection in the lung. However, the oral cavity is a dominant production site for exhaled HCN and this contribution can mask the HCN generated in the lung. It is thus important to understand the sources of HCN production in the oral cavity. By screening of oral anaerobes for HCN production, we observed that the genus of Porphyromonas, Prevotella and Fusobacterium generated low levels of HCN in vitro. This is the first study to show that oral anaerobes are capable of producing HCN in vitro. Further investigations were conducted on the species of P. gingivalis and we successfully detected HCN production (0.9-10.9 ppb) in the headspace of three P. gingivalis reference strains (ATCC 33277, W50 and OMG 434) and one clinical isolate. From P. gingivalis ATCC 33277 and W50, a strong correlation between HCN and CO2 concentrations (rs = 0.89, p < 0.001) was observed, indicating that the HCN production of P. gingivalis might be connected with the bacterial metabolic activity. These results indicate that our setup could be widely applied to the screening of in vitro HCN production by both aerobic and anaerobic bacteria.

Detection of hydrogen cyanide from oral anaerobes by cavity ring down spectroscopy.

PubMed

Chen, Wen; Roslund, Kajsa; Fogarty, Christopher L; Pussinen, Pirkko J; Halonen, Lauri; Groop, Per-Henrik; Metsälä, Markus; Lehto, Markku

2016-03-04

Hydrogen cyanide (HCN) has been recognized as a potential biomarker for non-invasive diagnosis of Pseudomonas aeruginosa infection in the lung. However, the oral cavity is a dominant production site for exhaled HCN and this contribution can mask the HCN generated in the lung. It is thus important to understand the sources of HCN production in the oral cavity. By screening of oral anaerobes for HCN production, we observed that the genus of Porphyromonas, Prevotella and Fusobacterium generated low levels of HCN in vitro. This is the first study to show that oral anaerobes are capable of producing HCN in vitro. Further investigations were conducted on the species of P. gingivalis and we successfully detected HCN production (0.9-10.9 ppb) in the headspace of three P. gingivalis reference strains (ATCC 33277, W50 and OMG 434) and one clinical isolate. From P. gingivalis ATCC 33277 and W50, a strong correlation between HCN and CO2 concentrations (rs = 0.89, p < 0.001) was observed, indicating that the HCN production of P. gingivalis might be connected with the bacterial metabolic activity. These results indicate that our setup could be widely applied to the screening of in vitro HCN production by both aerobic and anaerobic bacteria.

Anti-mycobacteria potential and synergistic effects of combined crude extracts of selected medicinal plants used by Bapedi traditional healers to treat tuberculosis related symptoms in Limpopo Province, South Africa.

PubMed

Komape, Nancy Patience Motlalepula; Bagla, Victor Patrick; Kabongo-Kayoka, Prudence; Masoko, Peter

2017-02-24

Tuberculosis is an infectious communicable disease and the causative agent of the disease has over the years developed resistance to streamline chemotherapeutic agents with dire consequences and there is a need for development of new and more potent alternatives. Constituents of leaves material of Combretum heroroense, Citrus lemon and Apodytes dimidiata were serially extracted using solvents of varying polarity. TLC finger print profile of the different extracts were determined by spraying eluted plates with vanillin sulphuric acid and 2, 2- diphenylpicryl hydrazyl (DPPH) for the presence of antioxidant constituents. Presence of different phytochemicals was determined using standard chemical test. Bioautography was used to determine the number of compounds present in sub-fractions active against Mycobacterium smegmatis. Minimum inhibitory concentration (MIC) values extract and sub-fractions were determined using serial microplate dilution method against M. smegmatis (ATCC 1441), M. tuberculosis (ATCC H37Rv) and multi-drug resistant TB (MDR-TB) field strain. Synergy of the crude extracts of the three plants was determined using microplate dilution method against M. smegmatis. Mass extracted by different solvents was less than 6% dry weight for all the plants. Phlobatannins were not detected in A. dimidiata, C. heroroense and C. lemon as well as cardiac glycosides in C. lemon and A. dimidiata, and saponins in C. heroroense. Sub-fractions of the different plants were shown to contain constituents with antioxidant activity with the highest number detected in C. heroroense. Bioautography results reveal the presence of a compound(s) in the ethyle acetate sub-fraction of C. heroroense and butanol, methanol/water, ethyl acetate and water no.2 subfractions of A. dimidiata, active against M. smegmatis that were not shown to have antioxidant capacity. MIC results for different crude extracts of the three plants against M. smegmatis ranges from 0.1 to 3 mg/ml. The average MIC for the synergistic effect of the plants ranged from 0.04 mg/ml to 1.25 mg/ml. An activity greater than that obtained for the reference drugs was shown for the butanol and hexane fractions of A. dimidiata (0.47 mg/ml) against the field strain of MDR-TB while that obtained for the M.TB (ATCC H37Rv) was 0.31 mg/ml. A significant finding shown in this study reveals the potent anti-mycobacteria potential of sub-fractions of A. dimidiata against MDR-TB field strain that can lead to the isolation of compounds that can be used to counter resistant strains of tuberculosis.

Rapid identification of Burkholderia mallei and Burkholderia pseudomallei by intact cell Matrix-assisted Laser Desorption/Ionisation mass spectrometric typing.

PubMed

Karger, Axel; Stock, Rüdiger; Ziller, Mario; Elschner, Mandy C; Bettin, Barbara; Melzer, Falk; Maier, Thomas; Kostrzewa, Markus; Scholz, Holger C; Neubauer, Heinrich; Tomaso, Herbert

2012-10-10

Burkholderia (B.) pseudomallei and B. mallei are genetically closely related species. B. pseudomallei causes melioidosis in humans and animals, whereas B. mallei is the causative agent of glanders in equines and rarely also in humans. Both agents have been classified by the CDC as priority category B biological agents. Rapid identification is crucial, because both agents are intrinsically resistant to many antibiotics. Matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-TOF MS) has the potential of rapid and reliable identification of pathogens, but is limited by the availability of a database containing validated reference spectra. The aim of this study was to evaluate the use of MALDI-TOF MS for the rapid and reliable identification and differentiation of B. pseudomallei and B. mallei and to build up a reliable reference database for both organisms. A collection of ten B. pseudomallei and seventeen B. mallei strains was used to generate a library of reference spectra. Samples of both species could be identified by MALDI-TOF MS, if a dedicated subset of the reference spectra library was used. In comparison with samples representing B. mallei, higher genetic diversity among B. pseudomallei was reflected in the higher average Eucledian distances between the mass spectra and a broader range of identification score values obtained with commercial software for the identification of microorganisms. The type strain of B. pseudomallei (ATCC 23343) was isolated decades ago and is outstanding in the spectrum-based dendrograms probably due to massive methylations as indicated by two intensive series of mass increments of 14 Da specifically and reproducibly found in the spectra of this strain. Handling of pathogens under BSL 3 conditions is dangerous and cumbersome but can be minimized by inactivation of bacteria with ethanol, subsequent protein extraction under BSL 1 conditions and MALDI-TOF MS analysis being faster than nucleic amplification methods. Our spectra demonstrated a higher homogeneity in B. mallei than in B. pseudomallei isolates. As expected for closely related species, the identification process with MALDI Biotyper software (Bruker Daltonik GmbH, Bremen, Germany) requires the careful selection of spectra from reference strains. When a dedicated reference set is used and spectra of high quality are acquired, it is possible to distinguish both species unambiguously. The need for a careful curation of reference spectra databases is stressed.

Rapid identification of Burkholderia mallei and Burkholderia pseudomallei by intact cell Matrix-assisted Laser Desorption/Ionisation mass spectrometric typing

PubMed Central

2012-01-01

Background Burkholderia (B.) pseudomallei and B. mallei are genetically closely related species. B. pseudomallei causes melioidosis in humans and animals, whereas B. mallei is the causative agent of glanders in equines and rarely also in humans. Both agents have been classified by the CDC as priority category B biological agents. Rapid identification is crucial, because both agents are intrinsically resistant to many antibiotics. Matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-TOF MS) has the potential of rapid and reliable identification of pathogens, but is limited by the availability of a database containing validated reference spectra. The aim of this study was to evaluate the use of MALDI-TOF MS for the rapid and reliable identification and differentiation of B. pseudomallei and B. mallei and to build up a reliable reference database for both organisms. Results A collection of ten B. pseudomallei and seventeen B. mallei strains was used to generate a library of reference spectra. Samples of both species could be identified by MALDI-TOF MS, if a dedicated subset of the reference spectra library was used. In comparison with samples representing B. mallei, higher genetic diversity among B. pseudomallei was reflected in the higher average Eucledian distances between the mass spectra and a broader range of identification score values obtained with commercial software for the identification of microorganisms. The type strain of B. pseudomallei (ATCC 23343) was isolated decades ago and is outstanding in the spectrum-based dendrograms probably due to massive methylations as indicated by two intensive series of mass increments of 14 Da specifically and reproducibly found in the spectra of this strain. Conclusions Handling of pathogens under BSL 3 conditions is dangerous and cumbersome but can be minimized by inactivation of bacteria with ethanol, subsequent protein extraction under BSL 1 conditions and MALDI-TOF MS analysis being faster than nucleic amplification methods. Our spectra demonstrated a higher homogeneity in B. mallei than in B. pseudomallei isolates. As expected for closely related species, the identification process with MALDI Biotyper software (Bruker Daltonik GmbH, Bremen, Germany) requires the careful selection of spectra from reference strains. When a dedicated reference set is used and spectra of high quality are acquired, it is possible to distinguish both species unambiguously. The need for a careful curation of reference spectra databases is stressed. PMID:23046611

Isolation and characterization of pathogenic Vibrio alginolyticus from diseased cobia Rachycentron canadum.

PubMed

Liu, Ping-Chung; Lin, Ji-Yang; Hsiao, Pei-Tze; Lee, Kuo-Kau

2004-01-01

Outbreaks of serious mortality among cultured juvenile cobia Rachycentron canadum L. (weighing 8-10 g) characterized by lethargy, dark skin and ascites in the peritoneal cavity while some fish possessing damaged eyes occurred in July and August of 2001 in Taiwan. Fifteen motile bacterial strains were isolated from head kidney and/or the ascites on tryptic soy agar supplemented with 1% NaCl (TSA1) and/or thiosulphate citrate bile salt (TCBS) sucrose agar plates during the two outbreaks. All the isolates were characterized and identified as Vibrio alginolyticus on the basis of biochemical characteristics, and comparisons with those of the reference strain V. alginolyticus ATCC 17749. The strain C3c01 (a representative of the 15 similar field isolates), was virulent to the cobia with an LD50 value of 3.28 x 10(4) colony forming units/g fish body weight. All the moribund/dead fish exhibited lethargy, dark skin and ascites in the peritoneal cavity as that observed in natural outbreaks. The same bacteria could be reisolated from kidney and the ascites of fish after bacterial challenge using TSA1 and TCBS plates. The results reveal that V. alginolyticus is an infectious agent of vibriosis in the cobia.

Characterization of a polyketide synthase in Aspergillus niger whose product is a precursor for both dihydroxynaphthalene (DHN) melanin and naphtho-γ-pyrone.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiang, Yi Ming; Meyer, Kristen M; Praseuth, Michael

2010-12-06

The genome sequencing of the fungus Aspergillus niger, an industrial workhorse, uncovered a large cache of genes encoding enzymes thought to be involved in the production of secondary metabolites yet to be identified. Identification and structural characterization of many of these predicted secondary metabolites are hampered by their low concentration relative to the known A. niger metabolites such as the naphtho-γ-pyrone family of polyketides. We deleted a nonreducing PKS gene in A. niger strain ATCC 11414, a daughter strain of A. niger ATCC strain 1015 whose genome was sequenced by the DOE Joint Genome Institute. This PKS encoding gene ismore » a predicted ortholog of alb1 from Aspergillus fumigatus which is responsible for production of YWA1, a precursor of fungal DHN melanin. Our results show that the A. niger alb1 PKS is responsible for the production of the polyketide precursor for DHN melanin biosynthesis. Deletion of alb1 elimnates the production of major metabolites, naphtho-γ-pyrones. The generation of an A. niger strain devoid of naphtho-γ-pyrones will greatly facilitate the elucidation of cryptic biosynthetic pathways in this organism.« less

The inhibitory effect of a Lactobacillus acidophilus derived biosurfactant on biofilm producer Serratia marcescens

PubMed Central

Shokouhfard, Maliheh; Kermanshahi, Rouha Kasra; Shahandashti, Roya Vahedi; Feizabadi, Mohammad Mehdi; Teimourian, Shahram

2015-01-01

Objective(s): Serratia marcescens is one of the nosocomial pathogen with the ability to form biofilm which is an important feature in the pathogenesis of S. marcescens. The aim of this study was to determine the anti-adhesive properties of a biosurfactant isolated from Lactobacillus acidophilus ATCC 4356, on S. marcescens strains. Materials and Methods: Lactobacillus acidophilus ATCC 4356 was selected as a probiotic strain for biosurfactant production. Anti-adhesive activities was determined by pre-coating and co- incubating methods in 96-well culture plates. Results: The FTIR analysis of derived biosurfactant revealed the composition as protein component. Due to the release of such biosurfactants, L. acidophilus was able to interfere with the adhesion and biofilm formation of the S. marcescens strains. In co-incubation method, this biosurfactant in 2.5 mg/ml concentration showed anti-adhesive activity against all tested strains of S. marcescens (P<0.05). Conclusion: Our results show that the anti-adhesive properties of L. acidophilus biosurfactant has the potential to be used against microorganisms responsible for infections in the urinary, vaginal and gastrointestinal tracts, as well as skin, making it a suitable alternative to conventional antibiotics. PMID:26730335

Use of 16S-23S rRNA spacer-region (SR)-PCR for identification of intestinal clostridia.

PubMed

Song, Yuli; Liu, Chengxu; Molitoris, Denise; Tomzynski, Thomas J; Mc Teague, Maureen; Read, Erik; Finegold, Sydney M

2002-12-01

The suitability of a species identification technique based on PCR analysis of 16S-23S rRNA spacer region (SR) polymorphism for human intestinal Clostridium species was evaluated. This SR-PCR based technique is highly reproducible and successfully differentiated the strains tested, which included 17 ATCC type strains of Clostridium and 152 human stool Clostridium isolates, at the species or intraspecies level. Ninety-eight of 152 stool isolates, including C. bifermentans, C. butyricum, C. cadaveris, C. orbiscindens, C. paraputrificum, C. pefringens, C. ramosum, C. scindens, C. spiroforme, C. symbiosum and C. tertium, were identified to species level by SR-PCR patterns that were identical to those of their corresponding ATCC type strains. The other 54 stool isolates distributed among ten SR-PCR patterns that are unique and possibly represent ten novel Clostridium species or subspecies. The species identification obtained by SR-PCR pattern analysis completely agreed with that obtained by 16S rRNA sequencing, and led to identification that clearly differed from that obtained by cellular fatty acid analysis for 23/152 strains (15%). These results indicate that SR-PCR provides an accurate and rapid molecular method for the identification of human intestinal Clostridium species.

Legionella norrlandica sp. nov., isolated from the biopurification systems of wood processing plants.

PubMed

Rizzardi, Kristina; Winiecka-Krusnell, Jadwiga; Ramliden, Miriam; Alm, Erik; Andersson, Sabina; Byfors, Sara

2015-02-01

Fourteen isolates of an unknown species identified as belonging to the genus Legionella by selective growth on BCYE agar were isolated from the biopurification systems of three different wood processing plants. The mip gene sequence of all 14 isolates was identical and a close match alignment revealed 86 % sequence similarity with Legionella pneumophila serogroup 8. The whole genome of isolate LEGN(T) was sequenced, and a phylogenetic tree based on the alignment of 16S rRNA, mip, rpoB, rnpB and the 23S-5S intergenic region clustered LEGN(T) with L. pneumophila ATCC 33152(T). Analysis of virulence factors showed that strain LEGN(T) carries the majority of known L. pneumophila virulence factors. An amoeba infection assay performed to assess the pathogenicity of strain LEGN(T) towards Acanthamoeba castellanii showed that it can establish a replication vacuole in A. castellanii but does not significantly affect replication of amoebae. Taken together, the results confirm that strain LEGN(T) represents a novel species of the genus Legionella, for which the name Legionella norrlandica sp. nov. is proposed. The type strain is LEGN(T) ( = ATCC BAA-2678(T) = CCUG 65936(T)). © 2015 IUMS.

Inhibition of oxidative phosphorylation for enhancing citric acid production by Aspergillus niger.

PubMed

Wang, Lu; Zhang, Jianhua; Cao, Zhanglei; Wang, Yajun; Gao, Qiang; Zhang, Jian; Wang, Depei

2015-01-16

The spore germination rate and growth characteristics were compared between the citric acid high-yield strain Aspergillus niger CGMCC 5751 and A. niger ATCC 1015 in media containing antimycin A or DNP. We inferred that differences in citric acid yield might be due to differences in energy metabolism between these strains. To explore the impact of energy metabolism on citric acid production, the changes in intracellular ATP, NADH and NADH/NAD+ were measured at various fermentation stages. In addition, the effects of antimycin A or DNP on energy metabolism and citric acid production was investigated by CGMCC 5751. By comparing the spore germination rate and the extent of growth on PDA plates containing antimycin A or DNP, CGMCC 5751 was shown to be more sensitive to antimycin A than ATCC 1015. The substrate-level phosphorylation of CGMCC 5751 was greater than that of ATCC 1015 on PDA plates with DNP. DNP at tested concentrations had no apparent effect on the growth of CGMCC 5751. There were no apparent effects on the mycelial morphology, the growth of mycelial pellets or the dry cell mass when 0.2 mg L(-1) antimycin A or 0.1 mg L(-1) DNP was added to medium at the 24-h time point. The concentrations of intracellular ATP, NADH and NADH/NAD+ of CGMCC 5751 were notably lower than those of ATCC 1015 at several fermentation stages. Moreover, at 96 h of fermentation, the citric acid production of CGMCC 5751 reached up to 151.67 g L(-1) and 135.78 g L(-1) by adding 0.2 mg L(-1) antimycin A or 0.1 mg L(-1) DNP, respectively, at the 24-h time point of fermentation. Thus, the citric acid production of CGMCC 5751 was increased by 19.89% and 7.32%, respectively. The concentrations of intracellular ATP, NADH and NADH/NAD+ of the citric acid high-yield strain CGMCC 5751 were notably lower than those of ATCC 1015. The excessive ATP has a strong inhibitory effect on citric acid accumulation by A. niger. Increasing NADH oxidation and appropriately reducing the concentration of intracellular ATP can accelerate glycolysis and the TCA cycle to enhance citric acid yield.

Developing a mesophilic co-culture for direct conversion of cellulose to butanol in consolidated bioprocess.

PubMed

Wang, Zhenyu; Cao, Guangli; Zheng, Ju; Fu, Defeng; Song, Jinzhu; Zhang, Junzheng; Zhao, Lei; Yang, Qian

2015-01-01

Consolidated bioprocessing (CBP) of butanol production from cellulosic biomass is a promising strategy for cost saving compared to other processes featuring dedicated cellulase production. CBP requires microbial strains capable of hydrolyzing biomass with enzymes produced on its own with high rate and high conversion and simultaneously produce a desired product at high yield. However, current reported butanol-producing candidates are unable to utilize cellulose as a sole carbon source and energy source. Consequently, developing a co-culture system using different microorganisms by taking advantage of their specific metabolic capacities to produce butanol directly from cellulose in consolidated bioprocess is of great interest. This study was mainly undertaken to find complementary organisms to the butanol producer that allow simultaneous saccharification and fermentation of cellulose to butanol in their co-culture under mesophilic condition. Accordingly, a highly efficient and stable consortium N3 on cellulose degradation was first developed by multiple subcultures. Subsequently, the functional microorganisms with 16S rRNA sequences identical to the denaturing gradient gel electrophoresis (DGGE) profile were isolated from consortium N3. The isolate Clostridium celevecrescens N3-2 exhibited higher cellulose-degrading capability was thus chosen as the partner strain for butanol production with Clostridium acetobutylicum ATCC824. Meanwhile, the established stable consortium N3 was also investigated to produce butanol by co-culturing with C. acetobutylicum ATCC824. Butanol was produced from cellulose when C. acetobutylicum ATCC824 was co-cultured with either consortium N3 or C. celevecrescens N3-2. Co-culturing C. acetobutylicum ATCC824 with the stable consortium N3 resulted in a relatively higher butanol concentration, 3.73 g/L, and higher production yield, 0.145 g/g of glucose equivalent. The newly isolated microbial consortium N3 and strain C. celevecrescens N3-2 displayed effective degradation of cellulose and produced considerable amounts of butanol when they were co-cultured with C. acetobutylicum ATCC824. This is the first report of application of co-culture to produce butanol directly from cellulose under mesophilic condition. Our results indicated that co-culture of mesophilic cellulolytic microbe and butanol-producing clostridia provides a technically feasible and more simplified way for producing butanol directly from cellulose.

Effect of estradiol on planktonic growth, coaggregation, and biofilm formation of the Prevotella intermedia group bacteria.

PubMed

Fteita, Dareen; Könönen, Eija; Söderling, Eva; Gürsoy, Ulvi Kahraman

2014-06-01

Alterations in the quantity and quality of biofilms at gingival margin are considered to play a role in the initiation and development of pregnancy-related gingivitis. Prevotella intermedia sensu lato is able to consume estradiol, the major sex hormone secreted during pregnancy, in the absence of vitamin K. The aim of the study was to examine the effect of estradiol on the planktonic growth, coaggregation, polysaccharide production, and biofilm formation of the P. intermedia group bacteria, namely P. intermedia, Prevotella nigrescens, and Prevotella pallens. In all experiments, the type strain (ATCC) and a clinical strain (AHN) of P. intermedia, P. nigrescens, and P. pallens were incubated with the concentrations of 0, 30, 90, and 120 nmol/L of estradiol. Planktonic growth was assessed by means of the colony forming unit method, while coaggregation and biofilm formation were assessed by spectrophotometric methods. In the determination of protein and polysaccharide levels, the Bradford and phenol-sulfuric acid methods were used, respectively. P. pallens AHN 9283 and P. nigrescens ATCC 33563 increased their numbers at planktonic stage with increasing estradiol concentrations. In 48-h biofilm tests, elevated protein levels were found for both strains of P. intermedia, and the strains P. nigrescens ATCC 33563 and P. pallens AHN 9283 in the presence of estradiol. The P. intermedia strains also increased the levels of polysaccharide formation in the biofilm. Coaggregation of the P. intermedia group organisms with Fusobacterium nucleatum was enhanced only in P. intermedia AHN 8290. In conclusion, our in vitro experiments indicate that estradiol regulates planktonic growth, coaggregation, polysaccharide production, and biofilm formation characteristics of P. intermedia, P. nigrescens, and P. pallens differently. These results may, at least partly, explain the differences seen in their contribution to the pathogenesis of pregnancy-related gingivitis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antibacterial activity and interaction mechanism of electrospun zinc-doped titania nanofibers.

PubMed

Amna, Touseef; Hassan, M Shamshi; Barakat, Nasser A M; Pandeya, Dipendra Raj; Hong, Seong Tshool; Khil, Myung-Seob; Kim, Hak Yong

2012-01-01

In this study, a biological evaluation of the antimicrobial activity of Zn-doped titania nanofibers was carried out using Escherichia coli ATCC 52922 (Gram negative) and Staphylococcus aureus ATCC 29231 (Gram positive) as model organisms. The utilized Zn-doped titania nanofibers were prepared by the electrospinning of a sol-gel composed of zinc nitrate, titanium isopropoxide, and polyvinyl acetate; the obtained electrospun nanofibers were vacuum dried at 80°C and then calcined at 600°C. The physicochemical properties of the synthesized nanofibers were determined by X-ray diffraction pattern, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, thermogravimetry, and transmission electron microscopy (TEM). The antibacterial activity and the acting mechanism of Zn-doped titania nanofibers against bacteria were investigated by calculation of minimum inhibitory concentration and analyzing the morphology of the bacterial cells following the treatment with nanofibers solution. Our investigations reveal that the lowest concentration of Zn-doped titania nanofibers solution inhibiting the growth of S. aureus ATCC 29231 and E. coli ATCC 52922 strains is found to be 0.4 and 1.6 μg/ml, respectively. Furthermore, Bio-TEM analysis demonstrated that the exposure of the selected microbial strains to the nanofibers led to disruption of the cell membranes and leakage of the cytoplasm. In conclusion, the combined results suggested doping promotes antimicrobial effect; synthesized nanofibers possess a very large surface-to-volume ratio and may damage the structure of the bacterial cell membrane, as well as depress the activity of the membranous enzymes which cause bacteria to die in due course.

Bacteriophage cocktail for biocontrol of Salmonella in dried pet food.

PubMed

Heyse, Serena; Hanna, Leigh Farris; Woolston, Joelle; Sulakvelidze, Alexander; Charbonneau, Duane

2015-01-01

Human salmonellosis has been associated with contaminated pet foods and treats. Therefore, there is interest in identifying novel approaches for reducing the risk of Salmonella contamination within pet food manufacturing environments. The use of lytic bacteriophages shows promise as a safe and effective way to mitigate Salmonella contamination in various food products. Bacteriophages are safe, natural, highly targeted antibacterial agents that specifically kill bacteria and can be targeted to kill food pathogens without affecting other microbiota. In this study, we show that a cocktail containing six bacteriophages had a broadspectrum activity in vitro against a library of 930 Salmonella enterica strains representing 44 known serovars. The cocktail was effective against 95% of the strains in this tested library. In liquid culture dose-ranging experiments, bacteriophage cocktail concentrations of ≥10(8) PFU/ml inactivated more than 90% of the Salmonella population (10(1) to 10(3) CFU/ml). Dried pet food inoculated with a mixture containing equal proportions of Salmonella serovars Enteritidis (ATCC 4931), Montevideo (ATCC 8387), Senftenberg (ATCC 8400), and Typhimurium (ATCC 13311) and then surface treated with the six-bacteriophage cocktail (≥2.5 ± 1.5 × 10(6) PFU/g) achieved a greater than 1-log (P < 0.001) reduction compared with the phosphate-buffered saline-treated control in measured viable Salmonella within 60 min. Moreover, this bacteriophage cocktail reduced natural contamination in samples taken from an undistributed lot of commercial dried dog food that tested positive for Salmonella. Our results indicate that bacteriophage biocontrol of S. enterica in dried pet food is technically feasible.

Characterization of certain bacterial strains for potential use as starter or probiotic cultures in dairy products.

PubMed

Monteagudo-Mera, A; Caro, I; Rodríguez-Aparicio, L B; Rúa, J; Ferrero, M A; García-Armesto, M R

2011-08-01

The present work was aimed at characterizing 12 strains of lactic acid bacteria (LAB) to obtain improved potential starter or probiotic cultures that could be used for making dairy products from ewe's milk and cow's milk. Eight strains with antimicrobial properties, isolated from ewe's milk and from cheese made from ewe's and/or cow's milk, were studied. They were identified as Enterococcus faecalis (five strains), Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides, and Lactobacillus paracasei subsp. paracasei (one strain of each species). Additionally, four strains were obtained from the American Type Culture Collection: Lactobacillus casei 393 (isolated from cheese), L. lactis subsp. lactis 11454 (origin nonspecified and a producer of nisin), and two strains isolated from human feces (L. paracasei subsp. paracasei 27092 and Lactobacillus rhamnosus 53103, antibacterial agent producer). All E. faecalis strains showed at least one virulence factor (either hemolysin or gelatinase), which emphasizes the importance of these studies in this species. Both L. lactis strains and most Lactobacillus spp. were good acidifiers in ewe's milk and cow's milk at 30°C. High β-galactosidase activity, as well as aminopeptidase activities that favor the development of desirable flavors in cheese, were detected in all Lactobacillus spp. strains. Furthermore, L. rhamnosus ATCC 53103 showed α-fucosidase activity (thought to help colonization of the intestine) and lack of α-glucosidase activity (a trait considered positive for diabetic and obese humans). This last enzymatic activity was also lacking in L. lactis ATCC 11454. L. mesenteroides was the only strain D(2)-lactic acid producer. The selection of any particular strain for probiotic or dairy cultures should be performed according to the technological and/or functional abilities needed.

Anti-Helicobacter pylori metabolites from Rhizoctonia sp. Cy064, an endophytic fungus in Cynodon dactylon.

PubMed

Ma, Y M; Li, Y; Liu, J Y; Song, Y C; Tan, R X

2004-07-01

A new benzophenone, named rhizoctonic acid (1), together with three known compounds monomethylsulochrin (2), ergosterol (3) and 3beta,5alpha,6beta-trihydroxyergosta-7,22-diene (4) were isolated through bioassay-guided fractionations from the culture of Rhizoctonia sp. (Cy064), an endophytic fungus in the leaf of Cynodon dactylon. The structure of the new acid 1 was elucidated to be 5-hydroxy-2-(2-hydroxy-6-methoxy-4-methylbenzoyl)-3-methoxybenzoic acid by a combination of spectral analyses. Furthermore, the structure of monomethylsulochrin 2 was confirmed by 13C-NMR analysis. All four metabolites were subjected to a more detailed in vitro assessment of their antibacterial action against five clinically isolated and one reference (ATCC 43504) Helicobacter pylori strains.

Lactobacillus rodentium sp. nov., from the digestive tract of wild rodents.

PubMed

Killer, J; Havlík, J; Vlková, E; Rada, V; Pechar, R; Benada, O; Kopečný, J; Kofroňová, O; Sechovcová, H

2014-05-01

Three strains of regular, long, Gram-stain-positive bacterial rods were isolated using TPY, M.R.S. and Rogosa agar under anaerobic conditions from the digestive tract of wild mice (Mus musculus). All 16S rRNA gene sequences of these isolates were most similar to sequences of Lactobacillus gasseri ATCC 33323T and Lactobacillus johnsonii ATCC 33200T (97.3% and 97.2% sequence similarities, respectively). The novel strains shared 99.2-99.6% 16S rRNA gene sequence similarities. Type strains of L. gasseri and L. johnsonii were also most related to the newly isolated strains according to rpoA (83.9-84.0% similarities), pheS (84.6-87.8%), atpA (86.2-87.7%), hsp60 (89.4-90.4%) and tuf (92.7-93.6%) gene sequence similarities. Phylogenetic studies based on 16S rRNA, hsp60, rpoA, atpA and pheS gene sequences, other genotypic and many phenotypic characteristics (results of API 50 CHL, Rapid ID 32A and API ZYM biochemical tests; cellular fatty acid profiles; cellular polar lipid profiles; end products of glucose fermentation) showed that these bacterial strains represent a novel species within the genus Lactobacillus. The name Lactobacillus rodentium sp. nov. is proposed to accommodate this group of new isolates. The type strain is MYMRS/TLU1T (=DSM 24759T=CCM 7945T).

Role of luxS in Stress Tolerance and Adhesion Ability in Lactobacillus plantarum KLDS1.0391

PubMed Central

Jia, Fang-Fang; Zheng, Hui-Qi; Sun, Si-Rui; Pang, Xue-Hui; Liang, Yu; Shang, Jia-Cui; Zhu, Zong-Tao

2018-01-01

Lactobacillus plantarum, a probiotic, has a high survival rate and high colonization ability in the gastrointestinal tract. Tolerance to the gastrointestinal environment and adhesion to intestinal epithelial cells by some Lactobacillus species (excluding L. plantarum) are related to luxS/AI-2. Here, the role of luxS in tolerance to simulated digestive juice (SDJ) and adhesion to Caco-2 cells by L. plantarum KLDS1.0391 (hereafter, KLDS1.0391) was investigated. The KLDS1.0391 luxS mutant strain was constructed by homologous recombination. When luxS was deleted, acid and bile salt tolerance and survival rates in SDJ significantly decreased (p < 0.05 for all). The ability of the luxS deletion strain to adhere to Caco-2 cells was markedly lower than that of the wild-type strain (p < 0.05). The ability of the luxS mutant strain to adhere (competition, exclusion, and displacement) to Escherichia coli ATCC 25922 was significantly lower than that of the wild-type strain (p < 0.05 for all). A significant decrease was noted only in the exclusion adhesion inhibition of the luxS mutant strain to Salmonella typhimurium ATCC 14028 (p < 0.05). These results indicate that the luxS gene plays an important role in the gastrointestinal environment tolerance and adhesion ability of KLDS1.0391. PMID:29651434

Biosurfactant production by Pseudomonas aeruginosain kefir and fish meal.

PubMed

Kaskatepe, Banu; Yildiz, Sulhiye; Gumustas, Mehmet; Ozkan, Sibel A

2015-01-01

The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM) and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956). The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production.

Development and Characterization of Lactose-Positive Pediococcus Species for Milk Fermentation

PubMed Central

Caldwell, S. L.; McMahon, D. J.; Oberg, C. J.; Broadbent, J. R.

1996-01-01

Bacteriophages against Streptococcus thermophilus are a growing problem in the Italian cheese industry. One possible control method involves replacing S. thermophilus in mozzarella starter blends with lactic acid bacteria from a different genus or species. In this study, we evaluated lactose-positive pediococci for this application. Because we could not identify any commercially available pediococci with fast acid-producing ability in milk, we transformed Pediococcus pentosaceus ATCC 25744, P. pentosaceus ATCC 25745, and Pediococcus acidilactici ATCC 12697 by electroporation with pPN-1, a 35-kb Lactococcus lactis lactose plasmid. Transformants of P. pentosaceus ATCC 25745 and P. acidilactici ATCC 12697 were then used to examine lactose-positive pediococci for properties related to milk fermentation. Both transformants rapidly produced acid and efficiently retained pPN-1 in lactose broth, and neither bacterium was attacked by bacteriophages in whey collected from commercial cheese facilities. Paired starter combinations of Pediococcus spp. and Lactobacillus helveticus LH100 exhibited synergistic pH reduction in milk, and small-scale cheese trials showed that these cultures could be used to manufacture part-skim mozzarella cheese. Results demonstrate that lactose-positive pediococci have potential as replacement cocci for S. thermophilus in Italian cheese starter blends and may facilitate development of new strain rotation schemes to combat S. thermophilus bacteriophage problems in mozzarella cheese plants. PMID:16535280

Optical mapping and sequencing of the Escherichia coli KO11 genome reveal extensive chromosomal rearrangements, and multiple tandem copies of the Zymomonas mobilis pdc and adhB genes.

PubMed

Turner, Peter C; Yomano, Lorraine P; Jarboe, Laura R; York, Sean W; Baggett, Christy L; Moritz, Brélan E; Zentz, Emily B; Shanmugam, K T; Ingram, Lonnie O

2012-04-01

Escherichia coli KO11 (ATCC 55124) was engineered in 1990 to produce ethanol by chromosomal insertion of the Zymomonas mobilis pdc and adhB genes into E. coli W (ATCC 9637). KO11FL, our current laboratory version of KO11, and its parent E. coli W were sequenced, and contigs assembled into genomic sequences using optical NcoI restriction maps as templates. E. coli W contained plasmids pRK1 (102.5 kb) and pRK2 (5.4 kb), but KO11FL only contained pRK2. KO11FL optical maps made with AflII and with BamHI showed a tandem repeat region, consisting of at least 20 copies of a 10-kb unit. The repeat region was located at the insertion site for the pdc, adhB, and chloramphenicol-resistance genes. Sequence coverage of these genes was about 25-fold higher than average, consistent with amplification of the foreign genes that were inserted as circularized DNA. Selection for higher levels of chloramphenicol resistance originally produced strains with higher pdc and adhB expression, and hence improved fermentation performance, by increasing the gene copy number. Sequence data for an earlier version of KO11, ATCC 55124, indicated that multiple copies of pdc adhB were present. Comparison of the W and KO11FL genomes showed large inversions and deletions in KO11FL, mostly enabled by IS10, which is absent from W but present at 30 sites in KO11FL. The early KO11 strain ATCC 55124 had no rearrangements, contained only one IS10, and lacked most accumulated single nucleotide polymorphisms (SNPs) present in KO11FL. Despite rearrangements and SNPs in KO11FL, fermentation performance was equal to that of ATCC 55124.

Rare actinomycetes Nocardia caishijiensis and Pseudonocardia carboxydivorans as endophytes, their bioactivity and metabolites evaluation.

PubMed

Tanvir, Rabia; Sajid, Imran; Hasnain, Shahida; Kulik, Andreas; Grond, Stephanie

2016-04-01

Two strains identified as Nocardia caishijiensis (SORS 64b) and Pseudonocardia carboxydivorans (AGLS 2) were isolated as endophytes from Sonchus oleraceus and Ageratum conyzoides respectively. The analysis of their extracts revealed them to be strongly bioactive. The N. caishijiensis extract gave an LC50 of 570 μg/ml(-1) in the brine shrimp cytotoxicity assay and an EC50 of 0.552 μg/ml(-1) in the DPPH antioxidant assay. Antimicrobial activity was observed against Methicillin resistant Staphlococcus aureus (MRSA) and Escherichia coli ATCC 25922 (14 mm), Klebsiella pneumoniae ATCC 706003 (13 mm), S. aureus ATCC 25923 (11 mm) and Candida tropicalis (20 mm). For the extract of P. carboxydivorans the EC50 was 0.670 μg/ml(-1) and it was observed to be more bioactive against Bacillus subtilis DSM 10 ATCC 6051 (21 mm), C. tropicalis (20 mm), S. aureus ATCC 25923 (17 mm), MRSA (17 mm), E. coli K12 (W1130) (16 mm) and Chlorella vulgaris (10 mm). The genotoxicity testing revealed a 20 mm zone of inhibition against the polA mutant strain E. coli K-12 AB 3027 suggesting damage to the DNA and polA genes. The TLC and bioautography screening revealed a diversity of active bands of medium polar and nonpolar compounds. Metabolite analysis by HPLC-DAD via UV/vis spectral screening suggested the possibility of stenothricin and bagremycin A in the mycelium extract of N. caishijiensis respectively. In the broth and mycelium extract of P. carboxydivorans borrelidin was suggested along with α-pyrone. The HPLC-MS revealed bioactive long chained amide derivatives such as 7-Octadecenamide, 9, 12 octadecandienamide. This study reports the rare actinomycetes N. caishijiensis and P. carboxydivorans as endophytes and evaluates their bioactive metabolites. Copyright © 2016 Elsevier GmbH. All rights reserved.

Antibacterial activity of peritoneal exudate in patients treated with 2 g cefotiam for surgical anti-microbial prophylaxis.

PubMed

Miglioli, P A; Schoeffel, U; Gabroska, E; Allerberger, F

1998-01-01

The objective of this study was to investigate the presence of antibacterial activity in peritoneal exudate (PE) of patients treated with cefotiam (CFT). CFT (2 g) was administered as a 'single-shot' antimicrobial prophylaxis to 6 patients at the beginning of colorectal resection. Samples of PE were collected from each patient on days 1, 2 and 3 after surgery. CFT was detectable in the samples of day 1 for 5 of the 6 patients. The influence of PE on antibacterial activity of the antimicrobial drug was evaluated carrying out the MICs of CFT against Escherichia coli K-12, E. coli (ATCC 10798), Klebsiella pneumoniae (ATCC 1003), Proteus rettgeri (Sanelli) and Staphylococcus aureus (ATCC 29213) with and without the addition of PE. The presence of PE enhanced the antimicrobial activity of CFT against gram-negative strains, but not against S. aureus (ATCC 29213). These results suggest the presence of substances in PE that possess endogenous antibacterial activity. Thus, antimicrobial activity in PE cannot be predicted by evaluating pathogen sensitivity in vitro only.

Acetone-butanol-ethanol production from substandard and surplus dates by Egyptian native Clostridium strains.

PubMed

Abd-Alla, Mohamed Hemida; Zohri, Abdel-Naser Ahmed; El-Enany, Abdel-Wahab Elsadek; Ali, Shimaa Mohamed

2015-04-01

One hundred and seven mesophilic isolates of Clostridium were isolated from agricultural soils cultivated with different plants in Assuit Governorate, Egypt. Eighty isolates (out of 107) showed the ability to produce ABE (Acetone, butanol and ethanol) on T6 medium ranging from 0.036 to 31.89 g/L. The highest numbers of ABE producing isolates were obtained from soil samples of potato contributing 27 isolates, followed by 18 isolates from wheat and 10 isolates from onion. On the other hand, there were three native isolates that produced ABE more than those produced by the reference isolate Clostridium acetobutylicum ATCC 824 (11.543 g/L). The three isolates were identified based on phenotypic and gene encoding 16S rRNA as Clostridium beijerinckii ASU10 (KF372577), Clostridium chauvoei ASU55 (KF372580) and Clostridium roseum ASU58 (KF372581). The highest ABE level from substandard and surplus dates was produced by C. beijerinckii ASU10 (24.07 g/L) comprising butanol 67.15% (16.16 g/L), acetone 30.73% (7.4 g/L) and ethanol 2.12% (0.51 g/L), while C. roseum ASU58 and C. chauvoei ASU55 produced ABE contributing 20.20 and 13.79 g/L, respectively. ABE production by C. acetobutylicum ATCC 824 was 15.01 g/L. This study proved that the native strains C. beijerinckii ASU10 and C. roseum ASU58 have high competitive efficacy on ABE production from economical substrate as substandard and surplus date fruits. Additionally, using this substrate without any nutritional components is considered to be a commercial substrate for desired ABE production. Copyright © 2014 Elsevier Ltd. All rights reserved.

The constituents of essential oil: antimicrobial and antioxidant activity of Micromeria congesta Boiss. & Hausskn. ex Boiss. from East Anatolia.

PubMed

Herken, Emine Nur; Celik, Ali; Aslan, Mustafa; Aydınlık, Nilüfer

2012-09-01

The chemical composition, antimicrobial activity, total phenol content, total antioxidant activity, and total oxidant status of the essential oil from Micromeria congesta Boiss. & Hausskn. ex Boiss. were investigated. Steam distillation was used to obtain the essential oil, and the chemical analyses were performed by gas chromatography-mass spectrometry. The antimicrobial activity was tested by an agar disc diffusion method against the tested microorganisms: Bacillus subtilis NRRL B-744, Bacillus cereus NRRL B-3711, Staphylococcus aureus ATCC 12598, S. aureus ATCC 25923, S. aureus ATCC 25933, Escherichia coli 0157H7, E. coli ATCC25922, Micrococcus luteus NRLL B-4375, Enterococcus faecalis ATCC 19433, Proteus vulgaris RSKK 96026, and Yersinia enterecolitica RSKK 1501. The major compounds found in volatiles of M. congesta were piperitone oxide, linalool oxide, veratrole, pulegone, dihydro carvone, naphthalene, iso-menthone, para-menthone, and cyclohexanone. Compared to that of reference antibiotics, the antibacterial activity of the essential oil is considered as significant. Results showed that M. congesta has the potential for being used in food and medicine depending on its antioxidant and antibacterial activity.

Isolation and Purification of Complex II from Proteus Mirabilis Strain ATCC 29245

PubMed Central

Shabbiri, Khadija; Ahmad, Waqar; Syed, Quratulain; Adnan, Ahmad

2010-01-01

A respiratory complex was isolated from plasma membrane of pathogenic Proteus mirabilis strain ATCC 29245. It was identified as complex II consisting of succinate:quinone oxidoreductase (EC 1.3.5.1) containing single heme b. The complex II was purified by ion-exchange chromatography and gel filtration. The molecular weight of purified complex was 116.5 kDa and it was composed of three subunits with molecular weights of 19 kDa, 29 kDa and 68.5 kDa. The complex II contained 9.5 nmoles of cytochrome b per mg protein. Heme staining indicated that the 19 kDa subunit was cytochrome b. Its reduced form showed absorptions peaks at 557.0, 524.8 and 424.4 nm. The α-band was shifted from 557.0 nm to 556.8 nm in pyridine ferrohemochrome spectrum. The succinate: quinone oxidoreductase activity was found to be high in this microorganism. PMID:24031557

High quality permanent draft genome sequence of Phaseolibacter flectens ATCC 12775 T, a plant pathogen of French bean pods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aizenberg-Gershtein, Yana; Izhaki, Ido; Lapidus, Alla

We report that the Phaseolibacter flectens strain ATCC 12775 T (Halpern et al., Int J Syst Evol Microbiol 63:268–273, 2013) is a Gram-negative, rod shaped, motile, aerobic, chemoorganotroph bacterium. Ph. flectens is as a plant-pathogenic bacterium on pods of French bean and was first identified by Johnson (1956) as Pseudomonas flectens. After its phylogenetic position was reexamined, Pseudomonas flectens was transferred to the family Enterobacteriaceae as Phaseolibacter flectens gen. nov., comb. nov. Here we describe the features of this organism, together with the draft genome sequence and annotation. The DNA GC content is 44.34 mol%. The chromosome length is 2,748,442more » bp. It encodes 2,437 proteins and 89 RNA genes. Ph. flectens genome is part of the Genomic Encyclopedia of Type Strains, Phase I: the one thousand microbial genomes study.« less

High quality permanent draft genome sequence of Phaseolibacter flectens ATCC 12775 T, a plant pathogen of French bean pods

DOE PAGES

Aizenberg-Gershtein, Yana; Izhaki, Ido; Lapidus, Alla; ...

2016-01-13

We report that the Phaseolibacter flectens strain ATCC 12775 T (Halpern et al., Int J Syst Evol Microbiol 63:268–273, 2013) is a Gram-negative, rod shaped, motile, aerobic, chemoorganotroph bacterium. Ph. flectens is as a plant-pathogenic bacterium on pods of French bean and was first identified by Johnson (1956) as Pseudomonas flectens. After its phylogenetic position was reexamined, Pseudomonas flectens was transferred to the family Enterobacteriaceae as Phaseolibacter flectens gen. nov., comb. nov. Here we describe the features of this organism, together with the draft genome sequence and annotation. The DNA GC content is 44.34 mol%. The chromosome length is 2,748,442more » bp. It encodes 2,437 proteins and 89 RNA genes. Ph. flectens genome is part of the Genomic Encyclopedia of Type Strains, Phase I: the one thousand microbial genomes study.« less

A role for the diazotrophic cyanobacterium, Cyanothece sp. strain ATCC 51142, in nitrogen cycling for CELSS applications.

PubMed

Schneegurt, M A; Sherman, L A

1996-01-01

Simple calculations show that fixed nitrogen regeneration in a CELSS may not be as efficient as stowage and resupply of fixed nitrogen compounds. However, fixed nitrogen regeneration may be important for the sustainability and safety of a deployed CELSS. Cyanothece sp. strain ATCC 51142, a unicellular, aerobic, diazotrophic cyanobacterium, with high growth rates and a robust metabolism, is a reasonable candidate organism for a biological, fixed nitrogen regeneration system. In addition, Cyanothece sp. cultures may be used to balance gas exchange ratio imparities between plants and humans. The regeneration of fixed nitrogen compounds by cyanobacterial cultures was examined in the context of a broad computer model/simulation (called CELSS-3D). When cyanothece sp. cultures were used to balance gas exchange imparities, the biomass harvested could supply as much as half of the total fixed nitrogen needed for plant biomass production.

Bacteriophages as Biological Control Agents of Enteric Bacteria Contaminating Edible Oysters.

PubMed

Le, Tuan Son; Southgate, Paul C; O'Connor, Wayne; Poole, Sue; Kurtbӧke, D Ipek

2018-05-01

Bacterial contamination on seafood resulting from unhygienic food-handling practices causes foodborne diseases and significant revenue losses. Moreover, control measures are complicated by a high prevalence of antibiotic-resistant bacteria. Alternative measures such as the phage therapy, therefore, is considered as an environmental and consumer-friendly biological control strategy for controlling such bacterial contamination. In this study, we determined the effectiveness of a bacteriophage cocktail in controlling E. coli strains [JM 109, ATCC 13706 and the, extended spectrum beta-lactamase resistant strain (ATCC BAA 196)] and S. enterica subsp. enterica (ATCC 13311) as single and combined contaminants of the edible oysters. Five different E. coli-specific phages (belonging to the Siphoviridae family) and a Salmonella phage (belonging to the Tectiviridae family) were successfully isolated from sewage water samples taken from a local sewage treatment plan in the Sunshine Coast region of Australia. Phage treatments applied to the pathogens when they were presented on the oysters as either single or combined hosts, resulted in significant decrease of the number of these bacteria on edible oysters. Results obtained indicated that bacteriophages could have beneficial applications in oyster-processing plants in controlling pathogenic bacterial infestations. This study thus contributes towards ongoing international efforts into the effective use of bacteriophages for biological control purposes.

Microgravity alters the physiological characteristics of Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895 under different nutrient conditions.

PubMed

Kim, H W; Matin, A; Rhee, M S

2014-04-01

The aim of this study is to provide understanding of microgravity effects on important food-borne bacteria, Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895, cultured in nutrient-rich or minimal medium. Physiological characteristics, such as growth (measured by optical density and plating), cell morphology, and pH, were monitored under low-shear modeled microgravity (LSMMG; space conditions) and normal gravity (NG; Earth conditions). In nutrient-rich medium, all strains except ATCC 35150 showed significantly higher optical density after 6 h of culture under LSMMG conditions than under NG conditions (P < 0.05). LSMMG-cultured cells were approximately 1.8 times larger than NG-cultured cells at 24 h; therefore, it was assumed that the increase in optical density was due to the size of individual cells rather than an increase in the cell population. The higher pH of the NG cultures relative to that of the LSMMG cultures suggests that nitrogen metabolism was slower in the latter. After 24 h of culturing in minimal media, LSMMG-cultured cells had an optical density 1.3 times higher than that of NG-cultured cells; thus, the higher optical density in the LSMMG cultures may be due to an increase in both cell size and number. Since bacteria actively grew under LSMMG conditions in minimal medium despite the lower pH, it is of some concern that LSMMG-cultured E. coli O157:H7 may be able to adapt well to acidic environments. These changes may be caused by changes in nutrient metabolism under LSMMG conditions, although this needs to be demonstrated in future studies.

Growth of probiotic bacteria and bifidobacteria in a soy yogurt formulation.

PubMed

Farnworth, E R; Mainville, I; Desjardins, M-P; Gardner, N; Fliss, I; Champagne, C

2007-05-01

Soy beverage and cows' milk yogurts were produced with Steptococcus thermophilus (ATCC 4356) and Lactobacillus delbrueckii subsp. bulgaricus (IM 025). The drop in pH during fermentation was faster in the soy beverage than in cows' milk, but the final pH values were similar. Yogurts were prepared with a yogurt starter in conjunction with either the probiotic bacteria Lactobacillus johnsonii NCC533 (La-1), Lactobacillus rhamnosus ATCC 53103 (GG) or human derived bifidobacteria. The presence of the probiotic bacteria did not affect the growth of the yogurt strains. Approximately 2 log increases in both L. rhamnosus GG and L. johnsonii La-1 were observed when each was added with the yogurt strains in both cows' milk and the soy beverage. Two of the five bifidobacteria strains grew well in the cows' milk and soy beverage during fermentation with the yogurt bacteria. High pressure liquid chromatography (HPLC) analyses showed that the probiotic bacteria and the bifidobacteria were using different sugars to support their growth, depending on whether the bacteria were growing in cows' milk or soy beverage.

Susceptibility of Staphylococcus aureus strains toward combinations of oxacillin-2,4-dihydroxychalcone.

PubMed

Talia, J M; Alvarez, M A; Debattista, N B; Pappano, N B

2009-11-01

In order to determine the existence of synergism of the bacteriostatic action of flavonoids against G(+) bacteria between a clinically interesting conventional antibiotic and a flavonoid, combinations of oxacillin (OXC) and 2,4-dihydroxychalcone (DCH) as enhancer were assayed against methicillin-sensitive Staphylococcus aureus ATCC 29 213 and methicillin-resistant S. aureus ATCC 43 300. Using a kinetic-turbidimetric method, growth kinetics was monitored in a broth containing variable amounts of OXC alone and combinations of variable OXC-constant DCH. The minimum inhibitory concentrations (MIC) of OXC alone and in combination with DCH were evaluated. For the 29 213 strain, OXC MIC was 25 microg/mL, while combinations of 2-8 microg/mL OXC with 10 microg/mL of DCH totally inhibited growth and showed synergism. The resistance of the 43 300 strain in the presence of OXC was verified; OXC-DCH combinations decreased bacterial growth by 35 %. DCH augments the action of OXC against methicillin-susceptible S. aureus and therefore constitutes a good bacteriostatic agent for methicillin-resistant S. aureus.

The genome of the insecticidal Chromobacterium subtsugae PRAA4-1 and its comparison with that of Chromobacterium violaceum ATCC 12472.

PubMed

Blackburn, Michael B; Sparks, Michael E; Gundersen-Rindal, Dawn E

2016-12-01

The genome of Chromobacterium subtsugae strain PRAA4-1, a betaproteobacterium producing insecticidal compounds, was sequenced and compared with the genome of C. violaceum ATCC 12472. The genome of C. subtsugae displayed a reduction in genes devoted to capsular and extracellular polysaccharide, possessed no genes encoding nitrate reductases, and exhibited many more phage-related sequences than were observed for C. violaceum. The genomes of both species possess a number of gene clusters predicted to encode biosynthetic complexes for secondary metabolites; these clusters suggest they produce overlapping, but distinct assortments of metabolites.

Synthesis and antituberculosis activity of new fatty acid amides.

PubMed

D'Oca, Caroline Da Ros Montes; Coelho, Tatiane; Marinho, Tamara Germani; Hack, Carolina Rosa Lopes; Duarte, Rodrigo da Costa; da Silva, Pedro Almeida; D'Oca, Marcelo Gonçalves Montes

2010-09-01

This work reports the synthesis of new fatty acid amides from C16:0, 18:0, 18:1, 18:1 (OH), and 18:2 fatty acids families with cyclic and acyclic amines and demonstrate for the first time the activity of these compounds as antituberculosis agents against Mycobacterium tuberculosis H(37)Rv, M. tuberculosis rifampicin resistance (ATCC 35338), and M. tuberculosis isoniazid resistance (ATCC 35822). The fatty acid amides derivate from ricinoleic acid were the most potent one among a series of tested compounds, with a MIC 6.25 microg/mL for resistance strains. Copyright 2010 Elsevier Ltd. All rights reserved.

Occurrence of toxicity among protease, amylase, and color mutants of a nontoxic soy sauce koji mold

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalayanamitr, A.; Bhumiratana, A.; Flegel, T.W.

A soy sauce koji mold, Aspergillus flavus var. columnaris Raper and Fennel (ATCC 44310), was treated with UV irradiation to obtain mutant strains possessing high protease activities, high amylase activities, and light-colored conidia. Selected mutant strains were tested for toxicity, and some were found acutely toxic to weanling rats, although all were negative for aflatoxin production.

A disruption of ctpA encoding carboxy-terminal protease attenuates Burkholderia mallei and induces partial protection in CD1 mice.

PubMed

Bandara, Aloka B; DeShazer, David; Inzana, Thomas J; Sriranganathan, Nammalwar; Schurig, Gerhardt G; Boyle, Stephen M

2008-09-01

Burkholderia mallei is the etiologic agent of glanders in solipeds (horses, mules and donkeys), and incidentally in carnivores and humans. Little is known about the molecular mechanisms of B. mallei pathogenesis. The putative carboxy-terminal processing protease (CtpA) of B. mallei is a member of a novel family of endoproteases involved in the maturation of proteins destined for the cell envelope. All species and isolates of Burkholderia carry a highly conserved copy of ctpA. We studied the involvement of CtpA on growth, cell morphology, persistence, and pathogenicity of B. mallei. A sucrose-resistant strain of B. mallei was constructed by deleting a major portion of the sacB gene of the wild type strain ATCC 23344 by gene replacement, and designated as strain 23344DeltasacB. A portion of the ctpA gene (encoding CtpA) of strain 23344DeltasacB was deleted by gene replacement to generate strain 23344DeltasacBDeltactpA. In contrast to the wild type ATCC 23344 or the sacB mutant 23344DeltasacB, the ctpA mutant 23344DeltasacBDeltactpA displayed altered cell morphologies with partially or fully disintegrated cell envelopes. Furthermore, relative to the wild type, the ctpA mutant displayed slower growth in vitro and less ability to survive in J774.2 murine macrophages. The expression of mRNA of adtA, the gene downstream of ctpA was similar among the three strains suggesting that disruption of ctpA did not induce any polar effects. As with the wild type or the sacB mutant, the ctpA mutant exhibited a dose-dependent lethality when inoculated intraperitoneally into CD1 mice. The CD1 mice inoculated with a non-lethal dose of the ctpA mutant produced specific serum immunoglobulins IgG1 and IgG2a and were partially protected against challenge with wild type B. mallei ATCC 23344. These findings suggest that CtpA regulates in vitro growth, cell morphology and intracellular survival of B. mallei, and a ctpA mutant protects CD1 mice against glanders.

Antibacterial activity of selected standard strains of lactic acid bacteria producing bacteriocins--pilot study.

PubMed

Bodaszewska-Lubas, Malgorzata; Brzychczy-Wloch, Monika; Gosiewski, Tomasz; Heczko, Piotr B

2012-10-25

In this paper, an attempt was made to evaluate the antibacterial potential of standard strains of lactic acid bacteria (LAB) producing bacteriocins of various classes, thus demonstrating various mechanisms of cell membrane damages against the Streptococcus agalactiae strains (Group B Streptococcus, GBS), depending on surface polysaccharides and surface alpha-like protein genes. Antimicrobial property of the strains of L. plantarum C 11, L. sakei DSMZ 6333, and L. lactis ATCC 11454 producing bacteriocins: JK and EF plantaricins, sakacin and nisin, respectively, against the GBS strains was evaluated. The chosen to the study GBS strains were represented by serotypes Ia, Ib, II, III, V and they had bca, epsilon, rib, alp2 or alp3 alpha-like protein genes. The experiment was conducted by means of suspension culture and the bacteria count was determined using the serial dilution method. A great ability of L. plantarum C 11 strain was proven to inhibit the GBS growth. The strain of L. sakei DSMZ 6333 did not demonstrate any ability to inhibit the growth of GBS, whereas L. lactis ATCC 11454 inhibited the growth of S. agalactiae indicator strains to a minor extent. Statistically significant differences were demonstrated between the GBS strains representing various serotypes against the antimicrobial activity of model LAB strains. The least sensitive to the activity of bacteriocins were the strains representing serotypes Ib and III, whereas the strains representing serotype II were the most sensitive. The sensitivity of the GBS strains to the antimicrobial activity of LAB was not dependent on alpha-like protein genes. Among the LAB standard strains producing bacteriocins, the strongest antimicrobial property was observed in the strain of L. plantarum C 11. Because of the generally known and verified strong antagonistic property of the strains of L. plantarum species against indicator bacteria, it is necessary to further pursue the research presented in this paper.

In Vitro Resistance Selection in Shigella flexneri by Azithromycin, Ceftriaxone, Ciprofloxacin, Levofloxacin, and Moxifloxacin

PubMed Central

Harris, Kayla A.

2017-01-01

ABSTRACT Shigella flexneri continues to be a major cause of diarrhea-associated illness, and increasing resistance to first-line antimicrobials complicates the treatment of infections caused by this pathogen. We investigated the pharmacodynamics of current antimicrobial treatments for shigellosis to determine the likelihood of resistance promotion with continued global antimicrobial use. The mutant prevention concentration (MPC) and mutant selection window (MSW) were determined for azithromycin, ceftriaxone, ciprofloxacin, levofloxacin, and moxifloxacin against a wild-type strain of S. flexneri (ATCC 12022) and an isogenic gyrA mutant (m-12022). Time-kill assays were performed to determine antimicrobial killing. Concentrations of approved doses of ciprofloxacin, levofloxacin, and moxifloxacin are predicted to surpass the MPC for a majority of the dosage interval against ATCC 12022. However, against m-12022, concentrations of all fluoroquinolones are predicted to fall below the MPC and remain in the MSW for a majority of the dosage interval. Concentrations of ceftriaxone fall within the MSW for the majority of the dosage interval for both strains. All agents other than azithromycin displayed bactericidal activity in time-kill assays. Results of pharmacodynamic analyses suggest that all tested fluoroquinolones would achieve a favorable area under the concentration-time curve (AUC)/MPC ratio for ATCC 12022 and would restrict selective enrichment of mutants but that mutant selection in m-12022 would be likely if ciprofloxacin were used. Based on pharmacodynamic analyses, azithromycin and ceftriaxone are predicted to promote mutant selection in both strains. Confirmation of these findings and examination of novel treatment regimens using in vivo studies are warranted. PMID:28483960

Construction of upp deletion mutant strains of Lactobacillus casei and Lactococcus lactis based on counterselective system using temperature-sensitive plasmid.

PubMed

Song, Li; Cui, Hongyu; Tang, Lijie; Qiao, Xinyuan; Liu, Min; Jiang, Yanping; Cui, Wen; Li, Yijing

2014-07-01

Integration plasmids are often used in constructing chromosomal mutations, as it enables the alternation of genes at any location by integration or replacement. Food-grade integration vectors can integrate into the host genome without introducing any selectable markers or residual bases, and the recombination often happens in non-coding region. In this study we used the temperature-sensitive pWV01 replicon to construct 2 chloramphenicol-resistant integration plasmids (pGBHC32-upp) containing the uracil phosphoribosyl transferase (upp) gene as a counterselective marker for Lactobacillus casei (L. casei) ATCC393 and Lactococcus lactis (L. lactis) MG1363. We then ligated the designed homologous arms to the pGBHC32-upp plasmids to allow their integration to the bacterial chromosome, and selected upp deletion mutants of L. casei ATCC393 and L. lactis MG1363 in the presence of 5-fluorouracil (5-FU). Analysis of genetic stability, growth curve, carbon utilization and scanning electronic microscopy showed that, except for 5-FU resistance, there were no significant differences between the wild type and mutant lactic acid bacteria. The integration system and the upp deletion strains could be used in the insertion or deletion of genes at any location of the chromosome of both L. casei ATCC 393 and L. lactis MG1363, and the homologous recombination would not introduce any selectable markers or residual bases. These mutant strains can be further investigated for heterologous protein expression and construction of a live mucosal vaccine carrier. Copyright © 2014 Elsevier B.V. All rights reserved.

Glycerol metabolism of Lactobacillus rhamnosus ATCC 7469: cloning and expression of two glycerol kinase genes.

PubMed

Alvarez, María de Fátima; Medina, Roxana; Pasteris, Sergio E; Strasser de Saad, Ana M; Sesma, Fernando

2004-01-01

Lactobacillus rhamnosus ATCC 7469 was able to grow in glycerol as the sole source of energy in aerobic conditions, producing lactate, acetate, and diacetyl. A biphasic growth was observed in the presence of glucose. In this condition, glycerol consumption began after glucose was exhausted from the culture medium. Glycerol kinase activity was detected in L. rhamnosus ATCC 7469, a characteristic of microorganisms which catabolize glycerol in aerobic conditions. Genetic analysis revealed that this strain possesses two glycerol kinase genes: gykA and glpK, that encode for two different glycerol kinases GykA and GlpK, respectively. The glpK geneis associated in an operon with alpha-glycerophosphate oxidase (glpO) and glycerol facilitator (glpF) genes. Transcriptional analysis revealed that only glpK is expressed when L. rhamnosus was grown on glycerol. Copyright 2004 S. Karger AG, Basel

Biochemical and antimicrobial activity of phloretin and its glycosilated derivatives present in apple and kumquat.

PubMed

Barreca, Davide; Bellocco, Ersilia; Laganà, Giuseppina; Ginestra, Giovanna; Bisignano, Carlo

2014-10-01

Phloretin and its glycosylated derivatives (phlorizin and phloretin 3',5'-di-C-glucoside) are dihydrochalcones that have many interesting biological properties. The results obtained showed that the dihydrochalcones are able to inhibit growth of Gram positive bacteria, in particular Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 13932 and methicillin-resistant S. aureus clinical strains. Moreover, phloretin is active also against the Gram negative bacteria Salmonella typhimurium ATCC 13311. The determination of the enzymatic activity of key metabolic enzymes allowed us to shed some light on the biochemical mechanism of aglycon cell growth inhibition, showing as it remarkably influences the energetic metabolism of S. aureus. In addition, structure/activity determinations highlighted that the presence of a glycosyl moiety bound to the chalcone structure dramatically decreases the antimicrobial activity of phloretin. Copyright © 2014 Elsevier Ltd. All rights reserved.

Differentiation of Shewanella putrefaciens and Shewanella alga on the basis of whole-cell protein profiles, ribotyping, phenotypic characterization, and 16S rRNA gene sequence analysis.

PubMed Central

Vogel, B F; Jørgensen, K; Christensen, H; Olsen, J E; Gram, L

1997-01-01

Seventy-six presumed Shewanella putrefaciens isolates from fish, oil drillings, and clinical specimens, the type strain of Shewanella putrefaciens (ATCC 8071), the type strain of Shewanella alga (IAM 14159), and the type strain of Shewanella hanedai (ATCC 33224) were compared by several typing methods. Numerical analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell protein and ribotyping patterns showed that the strains were separated into two distinct clusters with 56% +/- 10% and 40% +/- 14% similarity for whole-cell protein profiling and ribotyping, respectively. One cluster consisted of 26 isolates with 52 to 55 mol% G + C and included 15 human isolates, mostly clinical specimens, 8 isolates from marine waters, and the type strain of S. alga. This homogeneous cluster of mesophilic, halotolerant strains was by all analyses identical to the recently defined species S. alga (U. Simidu et al., Int. J. Syst. Bacteriol, 40:331-336, 1990). Fifty-two typically psychrotolerant strains formed the other, more heterogeneous major cluster, with 43 to 47 mol% G + C. The type strain of S. putrefaciens was included in this group. The two groups were confirmed by 16S rRNA gene sequence analysis. It is concluded that the isolates must be considered two different species, S. alga and S. putrefaciens, and that most mesophilic isolates formerly identified as S. putrefaciens belong to S. alga. The ecological role and potential pathogenicity of S. alga can be evaluated only if the organism is correctly identified. PMID:9172338

Pharmacodynamics of a New Streptogramin, XRP 2868, in Murine Thigh and Lung Infection Models

PubMed Central

Andes, D.; Craig, W. A.

2006-01-01

XRP 2868 is a new streptogramin antibiotic with broad-spectrum activity against gram-positive cocci. We used the neutropenic murine thigh and lung infection models to characterize the time course of antimicrobial activity of XRP 2868 and determine which pharmacokinetic/pharmacodynamic (PK/PD) parameter and magnitude best correlated with efficacy. Serum levels following four two- to fourfold-escalating single-dose levels of XRP 2868 were measured by liquid chromatography mass spectrometry assay. In vivo postantibiotic effects (PAEs) were determined after doses of 2.5, 10, and 40 mg/kg. Mice had 106.8 to 108.4 CFU/thigh of strains of Streptococcus pneumoniae ATCC 10813 or Staphylococcus aureus ATCC 29213 at the start of therapy when treated for 24 h with 2.5 to 640 mg/kg/day of XRP 2868 fractionated for 3-, 6-, 12-, and 24-h dosing regimens. Nonlinear regression analysis was used to determine which PK/PD parameter best correlated with CFU/thigh at 24 h. Pharmacokinetic studies exhibited peak dose values of 0.03 to 0.07, area under the concentration-time curve (AUC) dose values of 0.02 to 0.07, and half-lives of 0.35 to 1.27 h. XRP 2868 produced in vivo PAEs of 0.5 to 3.4 h with S. pneumoniae strain ATCC 10813 and −1.5 to 10.7 h with S. aureus strain ATCC 29213. The 24-h AUC/MIC was the PK/PD parameter that best correlated with efficacy. In subsequent studies, we used the neutropenic murine thigh infection model to determine if the magnitude of the AUC/MIC needed for the efficacy of XRP 2868 varied among pathogens (including resistant strains). Mice had 106.1 to 107.8 CFU/thigh of four isolates of S. aureus (three methicillin-susceptible and one methicillin-resistant strain) and nine isolates of S. pneumoniae (one penicillin-susceptible, four penicillin-intermediate, and four penicillin-resistant strains) when treated for 24 h with 0.16 to 640 mg/kg of XRP 2868 every 6 h. A sigmoid dose-response model was used to estimate the doses (mg/kg/24 h) required to achieve a net bacteriostatic affect over 24 h. MICs ranged from 0.06 to 0.25 μg/ml. The 24-h AUC/MICs for each static dose (20.7 to 252 mg/kg/day) varied from 3 to 70. Mean 24-h AUC/MICs ± standard deviations (SDs) for S. pneumoniae and S. aureus isolates were 14 ± 10 and 31 ± 16, respectively. Beta-lactam and macrolide resistance did not alter the magnitude of AUC/MIC required for efficacy. PMID:16377693

Pharmacodynamics of a new streptogramin, XRP 2868, in murine thigh and lung infection models.

PubMed

Andes, D; Craig, W A

2006-01-01

XRP 2868 is a new streptogramin antibiotic with broad-spectrum activity against gram-positive cocci. We used the neutropenic murine thigh and lung infection models to characterize the time course of antimicrobial activity of XRP 2868 and determine which pharmacokinetic/pharmacodynamic (PK/PD) parameter and magnitude best correlated with efficacy. Serum levels following four two- to fourfold-escalating single-dose levels of XRP 2868 were measured by liquid chromatography mass spectrometry assay. In vivo postantibiotic effects (PAEs) were determined after doses of 2.5, 10, and 40 mg/kg. Mice had 10(6.8) to 10(8.4) CFU/thigh of strains of Streptococcus pneumoniae ATCC 10813 or Staphylococcus aureus ATCC 29213 at the start of therapy when treated for 24 h with 2.5 to 640 mg/kg/day of XRP 2868 fractionated for 3-, 6-, 12-, and 24-h dosing regimens. Nonlinear regression analysis was used to determine which PK/PD parameter best correlated with CFU/thigh at 24 h. Pharmacokinetic studies exhibited peak dose values of 0.03 to 0.07, area under the concentration-time curve (AUC) dose values of 0.02 to 0.07, and half-lives of 0.35 to 1.27 h. XRP 2868 produced in vivo PAEs of 0.5 to 3.4 h with S. pneumoniae strain ATCC 10813 and -1.5 to 10.7 h with S. aureus strain ATCC 29213. The 24-h AUC/MIC was the PK/PD parameter that best correlated with efficacy. In subsequent studies, we used the neutropenic murine thigh infection model to determine if the magnitude of the AUC/MIC needed for the efficacy of XRP 2868 varied among pathogens (including resistant strains). Mice had 10(6.1) to 10(7.8) CFU/thigh of four isolates of S. aureus (three methicillin-susceptible and one methicillin-resistant strain) and nine isolates of S. pneumoniae (one penicillin-susceptible, four penicillin-intermediate, and four penicillin-resistant strains) when treated for 24 h with 0.16 to 640 mg/kg of XRP 2868 every 6 h. A sigmoid dose-response model was used to estimate the doses (mg/kg/24 h) required to achieve a net bacteriostatic affect over 24 h. MICs ranged from 0.06 to 0.25 microg/ml. The 24-h AUC/MICs for each static dose (20.7 to 252 mg/kg/day) varied from 3 to 70. Mean 24-h AUC/MICs +/- standard deviations (SDs) for S. pneumoniae and S. aureus isolates were 14 +/- 10 and 31 +/- 16, respectively. Beta-lactam and macrolide resistance did not alter the magnitude of AUC/MIC required for efficacy.

Live and heat-killed Lactobacillus spp. interfere with Streptococcus mutans and Streptococcus oralis during biofilm development on titanium surface.

PubMed

Ciandrini, E; Campana, R; Baffone, W

2017-06-01

This research investigates the ability of live and heat-killed (HK) Lactic Acid Bacteria (LAB) to interfere with Streptococcus mutans ATCC 25175 and Streptococcus oralis ATCC 9811 during biofilm formation. Eight Lactobacillus spp. and two oral colonizers, pathogenic Streptococcus mutans and resident Streptococcus oralis, were characterized for their aggregation abilities, cell surface properties and biofilm formation ability on titanium surface. Then, the interference activity of selected live and HK Lactobacillus spp. during S. mutans and S. oralis biofilm development were performed. The cell-free culture supernatants (CFCS) anti-biofilm activity was also determined. LAB possess good abilities of auto-aggregation (from 14.19 to 28.97%) and of co-aggregation with S. oralis. The cell-surfaces characteristics were most pronounced in S. mutans and S. oralis, while the highest affinities to xylene and chloroform were observed in Lactobacillus rhamnosus ATCC 53103 (56.37%) and Lactobacillus paracasei B21060 (43.83%). S. mutans and S. oralis developed a biofilm on titanium surface, while LAB showed a limited or no ability to create biofilm. Live and HK L. rhamnosus ATCC 53103 and L. paracasei B21060 inhibited streptococci biofilm formation by competition and displacement mechanisms with no substantial differences. The CFCSs of both LAB strains, particularly the undiluted one of L. paracasei B21060, decreased S. mutans and S. oralis biofilm formation. This study evidenced the association of LAB aggregation abilities and cell-surface properties with the LAB-mediated inhibition of S. mutans and S. oralis biofilm formation. Lactobacilli showed different mechanisms of action and peculiar strain-specific characteristics, maintained also in the heat-killed LAB. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inhibition of Listeria monocytogenes in Hot Dogs by Surface Application of Freeze-Dried Bacteriocin-Containing Powders from Lactic Acid Bacteria.

PubMed

Ünlü, Gülhan; Nielsen, Barbara; Ionita, Claudia

2016-06-01

Six lactic acid bacteria (LAB) strains, Lactococcus lactis BFE 920, L. lactis subsp. lactis ATCC 11454, L. lactis subsp. cremoris ATCC 14365, Lactobacillus curvatus L442, Lact. curvatus LTH 1174, and Lact. bavaricus MN, were grown in cheddar cheese whey supplemented with complex nutrient sources. Cell-free culture supernatants were freeze-dried, and the resulting bacteriocin-containing powders were applied on the surface of hot dogs that were inoculated (~4 log cfu/hot dog) with a five-strain Listeria monocytogenes cocktail. Hot dogs were vacuum-sealed and stored at 4 °C for 4 weeks. L. monocytogenes was enumerated, using both tryptic soy agar (TSA) and oxford listeria agar (OXA), on day 0 and at 1, 2, 3, and 4 weeks of the refrigerated storage. In hot dogs containing only the L. monocytogenes inoculum, L. monocytogenes counts increased from 4 up to 7 log cfu/hot dog. All samples containing freeze-dried bacteriocin-containing powders exhibited significantly lowered (P < 0.05) L. monocytogenes populations on the surface of hot dogs throughout the 4-week study except for bavaricin MN powder. Bacterial counts on hot dogs packed without any powder were statistically equal on day 0 when enumerated on OXA. Freeze-dried bacteriocin-containing powders from Lact. curvatus L442 and L. lactis subsp. cremoris ATCC 14365 decreased L. monocytogenes populations on the surface of hot dogs by greater than 2 log cfu/hot dog throughout the 4-week study. For the powdered bacteriocin preparations from L. lactis BFE 920, L. lactis subsp. lactis ATCC 11454, and Lact. curvatus LTH 1174, L. monocytogenes populations were determined to be approximately 3-log cfu/hot dog after 4 weeks of storage.

Antimicrobial Activity of Chitosan Films With Essential Oils Against Listeria monocytogenes on Cabbage.

PubMed

Jovanovic, Gordana D; Klaus, Anita S; P Niksic, Miomir

2016-09-01

The highest incidence of listeriosis, due to consumption of ready-to-eat foods and fresh, shredded, minimally processed vegetables, occurs among pregnant women and the elderly. In order to reduce the prevalence of listeriosis among consumers, better protective measures are recommended. Chitosan films, with or without added essential oils, represent a modern, safe method of preserving the quality of such vegetables and significantly reducing the incidence of Listeria monocytogenes in these foods. The present study was conducted to evaluate the antimicrobial properties of composite chitosan-gelatin films with and without essential oils against two strains of L. monocytogenes , ATCC 19115 and ATCC 19112, in fresh shredded cabbage. Shredded cabbage was inoculated with L. monocytogenes and packed between two layers of the chitosan composite film, then placed in Petri dishes. The prepared samples were stored at 4°C then analyzed for total viable count on PALCAM agar while incubated at 37°C, every 24 hours for 7 days. Average L. monocytogenes content ranged from 4.2 - 5.4 log CFU/g, reaching values of 7.2 - 8.6 log CFU/g in samples of untreated cabbage. A complete reduction of L. monocytogenes ATCC 19115 on cabbage was achieved after 120 hours in the presence of 0.5% chitosan film, whereas reduction of L. monocytogenes ATCC 19112 was achieved after 144 hours. In the presence of 1% chitosan film, the bacteria withered more quickly and complete reduction of both species of L. monocytogenes was achieved after 96 hours. All tested formulations of chitosan films exhibited strong antimicrobial activity on the growth of both strains of L. monocytogenes on cabbage. The best effect was achieved with a 1% chitosan concentration. The addition of essential oils increased the antimicrobial activity of all tested films.

Unraveling and engineering the production of 23,24-bisnorcholenic steroids in sterol metabolism

PubMed Central

Xu, Li-Qin; Liu, Yong-Jun; Yao, Kang; Liu, Hao-Hao; Tao, Xin-Yi; Wang, Feng-Qing; Wei, Dong-Zhi

2016-01-01

The catabolism of sterols in mycobacteria is highly important due to its close relevance in the pathogenesis of pathogenic strains and the biotechnological applications of nonpathogenic strains for steroid synthesis. However, some key metabolic steps remain unknown. In this study, the hsd4A gene from Mycobacterium neoaurum ATCC 25795 was investigated. The encoded protein, Hsd4A, was characterized as a dual-function enzyme, with both 17β-hydroxysteroid dehydrogenase and β-hydroxyacyl-CoA dehydrogenase activities in vitro. Using a kshAs-null strain of M. neoaurum ATCC 25795 (NwIB-XII) as a model, Hsd4A was further confirmed to exert dual-function in sterol catabolism in vivo. The deletion of hsd4A in NwIB-XII resulted in the production of 23,24-bisnorcholenic steroids (HBCs), indicating that hsd4A plays a key role in sterol side-chain degradation. Therefore, two competing pathways, the AD and HBC pathways, were proposed for the side-chain degradation. The proposed HBC pathway has great value in illustrating the production mechanism of HBCs in sterol catabolism and in developing HBCs producing strains for industrial application via metabolic engineering. Through the combined modification of hsd4A and other genes, three HBCs producing strains were constructed that resulted in promising productivities of 0.127, 0.109 and 0.074 g/l/h, respectively. PMID:26898409

Unraveling and engineering the production of 23,24-bisnorcholenic steroids in sterol metabolism.

PubMed

Xu, Li-Qin; Liu, Yong-Jun; Yao, Kang; Liu, Hao-Hao; Tao, Xin-Yi; Wang, Feng-Qing; Wei, Dong-Zhi

2016-02-22

The catabolism of sterols in mycobacteria is highly important due to its close relevance in the pathogenesis of pathogenic strains and the biotechnological applications of nonpathogenic strains for steroid synthesis. However, some key metabolic steps remain unknown. In this study, the hsd4A gene from Mycobacterium neoaurum ATCC 25795 was investigated. The encoded protein, Hsd4A, was characterized as a dual-function enzyme, with both 17β-hydroxysteroid dehydrogenase and β-hydroxyacyl-CoA dehydrogenase activities in vitro. Using a kshAs-null strain of M. neoaurum ATCC 25795 (NwIB-XII) as a model, Hsd4A was further confirmed to exert dual-function in sterol catabolism in vivo. The deletion of hsd4A in NwIB-XII resulted in the production of 23,24-bisnorcholenic steroids (HBCs), indicating that hsd4A plays a key role in sterol side-chain degradation. Therefore, two competing pathways, the AD and HBC pathways, were proposed for the side-chain degradation. The proposed HBC pathway has great value in illustrating the production mechanism of HBCs in sterol catabolism and in developing HBCs producing strains for industrial application via metabolic engineering. Through the combined modification of hsd4A and other genes, three HBCs producing strains were constructed that resulted in promising productivities of 0.127, 0.109 and 0.074 g/l/h, respectively.

Role of Candida albicans polymorphism in interactions with oral epithelial cells.

PubMed

Villar, C C; Kashleva, H; Dongari-Bagtzoglou, A

2004-08-01

Candida albicans is a polymorphic organism which undergoes morphologic transition between yeast, pseudohyphal and hyphal forms. The ability of C. albicans to change from yeast to filamentous types is a major virulence determinant of this organism. However, the exact role of hyphal transformation in establishing oral mucosal infection is still poorly understood. In this study we used mutants with defects in filamentation, as well as oral strains, which differ in their capacity to form true hyphae, to examine the role of hyphal transformation in the interactions of C. albicans with oral epithelial cells in vitro. These interactions included the ability of these strains to adhere to and injure epithelial cells, as well as their ability to trigger a proinflammatory cytokine response. We found that strains SC5314 and ATCC28366 formed true hyphae on epithelial cells, whereas strain ATCC32077 and the tup1/tup1 mutant formed only pseudohyphae. Double mutant efg1/efg1cph1/cph1 grew exclusively as blastospores. We also found that yeast and pseudohyphal strains showed reduced adherence capacity to oral keratinocytes and caused minimal cell damage. Moreover, we showed that both yeast and pseudohyphal forms have a strongly attenuated proinflammatory phenotype, since they failed to induce significant interleukin (IL)-1alpha and IL-8 responses by oral epithelial cells. Germination of C. albicans into true hyphae is particularly important in the interactions with oral epithelial cells in vitro.

In vitro expression of Streptococcus pneumoniae ply gene in human monocytes and pneumocytes.

PubMed

Hu, Da-Kang; Liu, Yang; Li, Xiang-Yang; Qu, Ying

2015-05-07

Streptococcus pneumoniae is one major cause of pneumonia in human and contains various virulence factors that contribute to pathogenesis of pneumococcal disease. This study investigated the role of pneumolysin, Ply, in facilitating S. pneumoniae invasion into the host blood stream. S. pneumoniae strains were isolated from clinical blood and sputum samples and confirmed by PCR. Expression of ply gene was assessed by infecting human monocytes and pneumocytes. A total of 23 strains of S. pneumoniae isolated from blood (n = 11) and sputum (n = 12) along with S. pneumoniae ATCC49619 were used to infect human monocyte (THP-1) and Type II pneumocyte (A549) cell lines. All clinical strains of S. pneumoniae showed higher expression of ply mRNA than the American Type Culture Collection (ATCC) strain. Among the clinical strains, blood isolates showed higher expression of ply genes than sputum isolates, i.e., 2(1.5)- to 2(1.6)-folds in THP-1 and 2(0.4)- to 2(4.9)-folds in A549 cell lines. The data from the current study demonstrated that ply gene of blood- and sputum-derived S. pneumoniae is differentially expressed in two different cell lines. Under survival pressure, ply is highly expressed in these two cell lines for blood-derived S. pneumoniae, indicating that ply gene may facilitate S. pneumoniae invasion into the host blood system.

Antibacterial and antifungal activities from Siamese crocodile blood.

PubMed

Leelawongtawon, Ratree; Siruntawineti, Jindawan; Chaeychomsri, Win; Sattaponpan, Chisanucha

2010-12-01

To evaluate the in vitro antimicrobial activity of the Siamese crocodile blood against bacteria and fungi. Thirty Siamese crocodile blood samples including freeze dried whole blood (FDWB), fresh serum (FS), and freeze dried serum (FDS) were evaluated for antimicrobial susceptibility and MIC values against ATCC-registered strains of nine bacterial species and two fungal species and one fungus isolated from a clinical specimen, by using the standard broth microdilution method and a modified resazurin microtiter plate assay. The result showed that FS (80 mg/ml) and FDS (100 mg/ml) inhibited Gram negative bacteria including Enterobacter aerogenes ATCC 13048, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 27736, Salmonella typhimurium ATCC 13311 and Pseudomonas aeruginosa ATCC 27853 with the susceptibility rate at 23.30%, 10.00%, 40.00%, 70.00%, and 86.67%, respectively for FS, and 30.00%, 10.00%, 43.33%, 76.67% and 90.00%, respectively for FDS. The MIC and MBC were in the range of 12.50-100.00 mg/ml and 25.00-100.00 mg/m1 respectively. FS and FDS also inhibited Cryptococcus neoformans 250309 and Aspergillus niger with the susceptibility rate at 90.00% and 80.00%, respectively for FS and 100.00% and 83.33%, respectively for FDS. The MIC was in the range of 25.00-100.00 mg/ml. However, FS and FDS did not inhibit Gram positive bacteria and did not kill fungi. FDWB (100 mg/ml) could neither inhibit bacteria nor fungi. FS and FDS from Siamese crocodile exhibited potential antibacterial and antifungal activities.

Spectrophotometric evaluation of selenium binding by Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 yeast.

PubMed

Kieliszek, Marek; Błażejak, Stanisław; Płaczek, Maciej

2016-05-01

In this study, the ability of selenium binding the biomas of Saccharomyces cerevisiae ATCC MYA-2200 and Candida utilis ATCC 9950 was investigated. Sodium selenite(IV) salts were added to the experimental media at concentrations of 10, 20, 40, and 60 mg Se(4+) L(-1). In the tested concentration range, one concentration reported a significant reduction in the biomass yield of both yeast strains. Intense growth was observed for C. utilis yeast, which reached the highest biomass yield of 15 gd.w.L(-1) after 24h cultivation in the presence of 10mg Se(4+) L(-1). Based on the use of spectrophotometric method for the determination of selenium content by using Variamine Blue as a chromogenic agent, efficient accumulation of this element in the biomass of the investigated yeast was observed. The highest amount of selenium, that is, 5.64 mg Se(4+)gd.w.(-1), was bound from the environment by S. cerevisiae ATCC MYA-2200 cultured in the presence of 60 mg Se(4+) L(-1) medium 72h Slightly less amount, 5.47 mg Se(4+) gd.w.(-1), was absorbed by C. utilis ATCC 9950 during similar cultural conditions. Based on the results of the biomass yield and the use of selenium from the medium, it can be observed that yeasts of the genus Candida are more efficient in binding this element, and this property finds practical application in the production of selenium-enriched yeast. Copyright © 2016 Elsevier GmbH. All rights reserved.

Green synthesis, biological and spectroscopic study on the interaction of multi-component Mannich bases of imidazo[2,1-b]benzothiazoles with human serum albumin.

PubMed

Maddili, Swetha K; Yandrati, Leela Prasad; Siddam, Shakuntala; Kannekanti, Vijaya Kumar; Gandham, Himabindu

2017-11-01

A series of Mannich bases of imidazo[2, l-b]benzothiazoles were prepared through one-pot multi-component reaction in the presence of water as an eco-friendly solvent. All the synthesized compounds were confirmed from IR, 1 HNMR, 13 CNMR, and Mass spectroscopy. Evaluation of in vitro anti-inflammatory and anti-microbial activities of all the synthesized derivatives was further accomplished. These results clearly displayed that compound 6d exhibited outstanding anti-inflammatory activity with a percentage inhibition of 70.23% by membrane stabilization method whereas 67.54% at 100μgmL -1 by the albumin denaturation method, which is comparable to the standard Diclofenac. Further screening against five fungal species (C. albicans ATCC 76615, C. mycoderma, C. utilis, A. flavus, and B. yeast) along with four gram positive (Methicillin-resistant S. aureus N315 (MRSA), Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 21216, and Micrococcus luteus ATCC 4698), and six Gram-negative bacterial strains (Escherichia coli DH52, Escherichia coli JM109, Salmonella dysenteriae, Pseudomonas aeruginosa ATCC 27853, Bacillus proteus ATCC13315 and Bacillus typhi) was carried out. These findings manifested that compound 7c displayed excellent antifungal efficacy while compound 7b revealed significant anti-microbial activity. In addition binding behaviour of compound 7b was investigated by binding study between calf thymus DNA and compound 7b by UV-Vis absorption spectroscopy and further research about HSA interactions was carried out. Copyright © 2017 Elsevier B.V. All rights reserved.

Aquimarina litoralis sp. nov., isolated from a coastal seawater.

PubMed

Oh, You-Sung; Kahng, Hyung-Yeel; Lee, Young Sun; Yoon, Byoung-Jun; Lim, Sang-Bin; Jung, Jae Sung; Oh, Duck-Chul; Lee, Dong-Heon

2010-08-01

A strictly aerobic, red-pigmented, non-motile, catalase- and oxidase-positive, Gram-staining-negative bacterium, designated strain CNURIC011(T), was isolated from seawater off the coast of Jeju Island in Korea. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain CNURIC011(T) belongs to the genus Aquimarina in the family Flavobacteriaceae. 16S rRNA gene sequence analysis revealed that the close relatives of the novel strain are Aquimarina latercula ATCC 23177(T), Aquimarina marcrocephali JAMB N27(T), Aquimarina intermedia KMM 6258(T), Aquimarina muelleri KMM 6020(T), and Aquimarina brevivitae SMK-19(T), with sequence similarities of 97.6, 96.6, 96.0, 95.6, and 94.2%, respectively. DNA-DNA hybridization revealed that the level of relatedness between strain CNURIC011(T) and Aquimarina latercula ATCC 23177(T) (=KCTC 2912(T)) was 4.9%. The DNA G+C content was 35.8 mol% and the major respiratory quinone was MK-6. The major fatty acids were iso-C(15:0) (14.9%), C(15:0) (13.9%), iso-C(17:0) 3-OH (12.6%), iso-C(15:1) G (7.3%), and iso-C(17:1) omega9c (7.2%). On the basis of phenotypic, phylogenetic, and genotypic data, strain CNURIC011(T) represents a novel species within the genus Aquimarina, for which the name Aquimarina litoralis sp. nov. is proposed. The type strain is CNURIC011(T) (=KCTC 22614(T) =JCM 15974(T)).

The genome sequence of E. coli W (ATCC 9637): comparative genome analysis and an improved genome-scale reconstruction of E. coli

PubMed Central

2011-01-01

Background Escherichia coli is a model prokaryote, an important pathogen, and a key organism for industrial biotechnology. E. coli W (ATCC 9637), one of four strains designated as safe for laboratory purposes, has not been sequenced. E. coli W is a fast-growing strain and is the only safe strain that can utilize sucrose as a carbon source. Lifecycle analysis has demonstrated that sucrose from sugarcane is a preferred carbon source for industrial bioprocesses. Results We have sequenced and annotated the genome of E. coli W. The chromosome is 4,900,968 bp and encodes 4,764 ORFs. Two plasmids, pRK1 (102,536 bp) and pRK2 (5,360 bp), are also present. W has unique features relative to other sequenced laboratory strains (K-12, B and Crooks): it has a larger genome and belongs to phylogroup B1 rather than A. W also grows on a much broader range of carbon sources than does K-12. A genome-scale reconstruction was developed and validated in order to interrogate metabolic properties. Conclusions The genome of W is more similar to commensal and pathogenic B1 strains than phylogroup A strains, and therefore has greater utility for comparative analyses with these strains. W should therefore be the strain of choice, or 'type strain' for group B1 comparative analyses. The genome annotation and tools created here are expected to allow further utilization and development of E. coli W as an industrial organism for sucrose-based bioprocesses. Refinements in our E. coli metabolic reconstruction allow it to more accurately define E. coli metabolism relative to previous models. PMID:21208457

Vibrio japonicus sp. nov., a novel member of the Nereis clade in the genus Vibrio isolated from the coast of Japan

PubMed Central

2017-01-01

A novel Vibrio strain, JCM 31412T, was isolated from seawater collected from the Inland Sea (Setonaikai), Japan, and characterized as a Gram-negative, oxidase-positive, catalase-negative, facultatively anaerobic, motile, ovoid-shaped bacterium with one polar flagellum. Based on 16S rDNA gene identity, strain JCM 31412T showed a close relationship with type strains of Vibrio brasiliensis (LMG 20546T, 98.2% identity), V. harveyi (NBRC 15634T, 98.2%), V. caribbeanicus (ATCC BAA-2122T, 97.8%) and V. proteolyticus (NBRC 13287T, 97.8%). The G+C content of strain JCM 31412T DNA was 46.8%. Multi-locus sequence analysis (MLSA) of eight loci (ftsZ, gapA, gyrB, mreB, pyrH, recA, rpoA and topA; 5535bp) further clustered strain JCM 31412T in the Nereis clade, genus Vibrio. Phenotypically, strain JCM 31412T differed from the closest related Vibrio species in its utilization of melibiose and raffinose, and its lack of casein and gelatin hydrolysis. It was further differentiated based on its fatty acid composition, specifically properties of C12:03OH and summed features, which were significantly different from those of V. brasiliensis, V. nigripulchritudo and V. caribbeanicus type strains. Overall, the results of DNA-DNA hybridization, and physiological and biochemical analysis differentiated strain JCM 31412T from other described species of the genus Vibrio. Based on these polyphasic taxonomic findings, it was therefore concluded that JCM 31412T was a novel Vibrio species, for which the name Vibrio japonicus sp. nov. was proposed, with JCM 31412T (= LMG 29636T = ATCC TSD-62T) as the type strain. PMID:28231272

Complete genome sequence of Corynebacterium glutamicum CP, a Chinese l-leucine producing strain.

PubMed

Gui, Yongli; Ma, Yuechao; Xu, Qingyang; Zhang, Chenglin; Xie, Xixian; Chen, Ning

2016-02-20

Here, we report the complete genome sequence of Corynebacterium glutamicum CP, an industrial l-leucine producing strain in China. The whole genome consists of a circular chromosome and a plasmid. The comparative genomics analysis shows that there are many mutations in the key enzyme coding genes relevant to l-leucine biosynthesis compared to C. glutamicum ATCC 13032. Copyright © 2016 Elsevier B.V. All rights reserved.

Recombinant Zymomonas mobilis with improved xylose utilization

DOEpatents

Zhang, Min

2003-05-20

A strain derived from Zymomonas mobilis ATCC31821 or its derivative capable of producing ethanol upon fermentation of a carbohydrate medium containing xylose to provide enhanced xylose utilization and enhanced ethanol process yield, the strain or its derivative comprising exogenous genes encoding xylose isornerase, xylulokinase, transaldolase and transketolase, the genes are fused to at least one promotor recognized by Zymomonas which regulates the expression of at least one of the genes.

Thermal resistance of Saccharomyces yeast ascospores in beers.

PubMed

Milani, Elham A; Gardner, Richard C; Silva, Filipa V M

2015-08-03

The industrial production of beer ends with a process of thermal pasteurization. Saccharomyces cerevisiae and Saccharomyces pastorianus are yeasts used to produce top and bottom fermenting beers, respectively. In this research, first the sporulation rate of 12 Saccharomyces strains was studied. Then, the thermal resistance of ascospores of three S. cerevisiae strains (DSMZ 1848, DSMZ 70487, Ethanol Red(®)) and one strain of S. pastorianus (ATCC 9080) was determined in 4% (v/v) ethanol lager beer. D60 °C-values of 11.2, 7.5, 4.6, and 6.0 min and z-values of 11.7, 14.3, 12.4, and 12.7 °C were determined for DSMZ 1848, DSMZ 70487, ATCC 9080, and Ethanol Red(®), respectively. Lastly, experiments with 0 and 7% (v/v) beers were carried out to investigate the effect of ethanol content on the thermal resistance of S. cerevisiae (DSMZ 1848). D55 °C-values of 34.2 and 15.3 min were obtained for 0 and 7% beers, respectively, indicating lower thermal resistance in the more alcoholic beer. These results demonstrate similar spore thermal resistance for different Saccharomyces strains and will assist in the design of appropriate thermal pasteurization conditions for preserving beers with different alcohol contents. Copyright © 2015 Elsevier B.V. All rights reserved.

Sensitivity to disinfection of bacterial indicator organisms for monitoring the Salmonella Enteritidis status of layer farms after cleaning and disinfection.

PubMed

Dewaele, I; Ducatelle, R; Herman, L; Heyndrickx, M; De Reu, K

2011-06-01

The present study evaluated Escherichia coli, Enterococcus faecalis, and Enterococcus hirae as potential indicator organisms for the possible Salmonella Enteritidis (SE) presence in layer farms after cleaning and disinfection by comparing their susceptibility to disinfection. A quantitative suspension disinfection test according to European Standard EN1656 was performed using disinfection products CID20 and Virocid (both from CID Lines, Ieper, Belgium). In a preliminary test, the sensitivity to both disinfection products was compared between ATCC strains of SE, E. coli, En. faecalis, and En. hirae. The sensitivity of SE to disinfection was most comparable to that of E. coli. A second disinfection test compared the elimination of E. coli to SE ATCC strains as well as field strains. Results showed no significant effect regarding the strain (P > 0.05 for CID20 and Virocid), meaning that no difference was detected in sensitivity toward disinfection. When comparing the sensitivity in general at species level for all concentrations of disinfectant used, no significant difference was found between E. coli and SE in sensitivity to Virocid (P > 0.05). In conclusion, because of its similar response to disinfection in a suspension disinfection test, E. coli could be used as an indicator for possible Salmonella presence after cleaning and disinfection.

Whole-genome sequence of Erysipelothrix larvae LV19(T) (=KCTC 33523(T)), a useful strain for arsenic detoxification, from the larval gut of the rhinoceros beetle, Trypoxylus dichotomus.

PubMed

Lim, Sooyeon; Rhee, Moon-Soo; Chang, Dong-Ho; Kim, Byoung-Chan

2016-04-10

Erysipelothrix larvae LV19(T) was preliminary isolated from the larval gut of a rhinoceros beetle, Trypoxylus dichotomus in Korea. Here, we present the whole genome sequence of E. larvae LV19(T) strain, which consisted of 2,511,486 base pairs with a GC content of 37.4% and one plasmid. Unlike other Erysipelothrix strains (SY 1027, Fujisawa and ATCC 19414), the arsenic-resistance genes were identified in LV19(T) strain. Copyright © 2016 Elsevier B.V. All rights reserved.

Biochemical characterization of a recombinant Lactobacillus acidophilus strain expressing exogenous FomA protein.

PubMed

Ma, Li; Li, Fei; Zhang, Xiangyu; Feng, Xiping

2018-04-30

In previous research, to combine the immunogenicity of Fusobacterium nucleatum (F. nucleatum) and the probiotic properties of Lactobacillus acidophilus (L. acidophilus), we constructed a FomA-expressing L. acidophilus strain and assessed its immunogenicity. Our findings indicated that oral administration of the recombinant L. acidophilus strain reduced the risk of periodontal infection by Porphyromonas gingivalis (P. gingivalis) and F. nucleatum. However, because the exogenous FomA is an heterologous protein for the original bacterium, in this study, we assessed whether the biochemical characteristics of the recombinant L. acidophilus strain change due to the expression of the exogenous FomA protein. To test the biochemical characteristics of a recombinant L. acidophilus strain expressing exogenous FomA and assess its antibiotic sensitivity. We assessed the colony morphology, growth, acid production, and carbohydrate fermentation abilities of the recombinant L. acidophilus strain. In addition, we tested the adhesive ability and antimicrobial activity of the recombinant and assessed its antibiotic sensitivity through a drug susceptibility test. The experimental results showed that the colony and microscopic morphology of the recombinant L. acidophilus strain was consistent with the original strain, and the recombinant strain grew well when cultured under aerobic or anaerobic conditions, exhibiting a growth rate that was identical to that of the standard strain. Similarly, the supernatants of the recombinant L. acidophilus can inhibit the growth of E. coli and P. gingivalis at different concentrations, and the recombinant strain displayed essentially the same drug sensitivity profile as the original L. acidophilus. However, to our surprise, the recombinant strains exhibited a greater adhesion ability than the reference strain. Our study demonstrated that, in addition to an increased adhesion ability, the recombinant L. acidophilus strain maintained the basic characteristics of the standard strain ATCC 4356, including antibiotic sensitivity. Thus, the recombinant strains have great potential to be utilized as a safe and effective periodontitis vaccine in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

In vitro-in vivo sequence studies as a method of selecting the most efficacious alcohol-based solution for hygienic hand disinfection.

PubMed

Herruzo, R; Vizcaino, M J; Herruzo, I

2010-05-01

The use of alcohol-based hand rubs serves to reduce hospital-acquired infections. Many products of this type are now on offer and it is essential to know how to rank their efficacy. A sequence of tests is proposed here to compare any given new alcohol-based solution against the reference solution (60% 2-isopropyl-alcohol) with 30 s of contact time: (i) in vitro (with pig skin as carrier) testing of >30 species of microorganism; (ii) in vitro assessment of residual efficacy (after 30 min of drying); (iii) in vivo study of transient microbiota (modification of the EN 1500 standard procedure) using four ATCC strains; (iv) in vivo study of resident hand microbiota. After performing the in vitro evaluation of seven alcohol-based hand rubs, the two most efficacious (chlorhexidine-quac-alcohol and mecetronium- alcohol) were chosen and studied, comparatively with the reference solution (60% isopropyl alcohol), in vitro (for chemical sustainability on the skin) and in vivo (against transient and resident microbiota). Chlorhexidine-quac-alcohol proved to be significantly superior to mecetronium-alcohol or the reference solution in all tests, except against resident microbiota for which the improvement was not statistically significant.

Cloacibacterium normanense gen. nov., sp. nov., a novel bacterium in the family Flavobacteriaceae isolated from municipal wastewater.

PubMed

Allen, Toby D; Lawson, Paul A; Collins, Matthew D; Falsen, Enevold; Tanner, Ralph S

2006-06-01

Phenotypic and phylogenetic studies were performed on three isolates of an unknown Gram-negative, facultatively anaerobic, non-motile, yellow-pigmented, rod-shaped organism isolated from raw sewage. 16S rRNA gene sequence analysis indicated that these strains were members of the Bergeyella-Chryseobacterium-Riemerella branch of the family Flavobacteriaceae. The unknown bacterium was readily distinguished from reference strains by 16S rRNA gene sequencing and biochemical tests. The organism contained menaquinone MK-6 as the predominant respiratory quinone and had a DNA G+C content of 31 mol%. A most probable number-PCR approach was developed to detect, and estimate the numbers of, this organism. Untreated wastewater from one plant yielded an estimated count of 1.4 x 10(5) cells ml(-1), and untreated wastewater from a second plant yielded an estimated count of 1.4 x 10(4) cells ml(-1). Signal was not detected from treated effluent or from human stool specimens. On the basis of the results of the study presented, it is proposed that the unknown bacterium be classified in a novel genus Cloacibacterium, as Cloacibacterium normanense gen. nov., sp. nov., which is also the type species. The type strain of Cloacibacterium normanense is strain NRS1(T) (=CCUG 46293(T) = CIP 108613(T) = ATCC BAA-825(T) = DSM 15886(T)).

Biosynthetic Genes for the Tetrodecamycin Antibiotics

PubMed Central

Gverzdys, Tomas

2016-01-01

ABSTRACT We recently described 13-deoxytetrodecamycin, a new member of the tetrodecamycin family of antibiotics. A defining feature of these molecules is the presence of a five-membered lactone called a tetronate ring. By sequencing the genome of a producer strain, Streptomyces sp. strain WAC04657, and searching for a gene previously implicated in tetronate ring formation, we identified the biosynthetic genes responsible for producing 13-deoxytetrodecamycin (the ted genes). Using the ted cluster in WAC04657 as a reference, we found related clusters in three other organisms: Streptomyces atroolivaceus ATCC 19725, Streptomyces globisporus NRRL B-2293, and Streptomyces sp. strain LaPpAH-202. Comparing the four clusters allowed us to identify the cluster boundaries. Genetic manipulation of the cluster confirmed the involvement of the ted genes in 13-deoxytetrodecamycin biosynthesis and revealed several additional molecules produced through the ted biosynthetic pathway, including tetrodecamycin, dihydrotetrodecamycin, and another, W5.9, a novel molecule. Comparison of the bioactivities of these four molecules suggests that they may act through the covalent modification of their target(s). IMPORTANCE The tetrodecamycins are a distinct subgroup of the tetronate family of secondary metabolites. Little is known about their biosynthesis or mechanisms of action, making them an attractive subject for investigation. In this paper we present the biosynthetic gene cluster for 13-deoxytetrodecamycin in Streptomyces sp. strain WAC04657. We identify related clusters in several other organisms and show that they produce related molecules. PMID:27137499

Interlaboratory Study of Quality Control Isolates for a Broth Microdilution Method (Modified CLSI M38-A) for Testing Susceptibilities of Dermatophytes to Antifungals▿

PubMed Central

Ghannoum, M. A.; Arthington-Skaggs, B.; Chaturvedi, V.; Espinel-Ingroff, A.; Pfaller, M. A.; Rennie, R.; Rinaldi, M. G.; Walsh, T. J.

2006-01-01

The Clinical and Laboratory Standards Institute (CLSI; formerly National Committee for Clinical Laboratory Standards, or NCCLS) M38-A standard for the susceptibility testing of filamentous fungi does not specifically address the testing of dermatophytes. In 2003, a multicenter study investigated the reproducibility of the microdilution method developed at the Center for Medical Mycology, Cleveland, Ohio, for testing the susceptibility of dermatophytes. Data from that study supported the introduction of this method for testing dermatophytes in the future version of the CLSI M38-A standard. In order for the method to be accepted by CLSI, appropriate quality control isolates needed to be identified. To that end, an interlaboratory study, involving the original six laboratories plus two additional sites, was conducted to evaluate potential candidates for quality control isolates. These candidate strains included five Trichophyton rubrum strains known to have elevated MICs to terbinafine and five Trichophyton mentagrophytes strains. Antifungal agents tested included ciclopirox, fluconazole, griseofulvin, itraconazole, posaconazole, terbinafine, and voriconazole. Based on the data generated, two quality control isolates, one T. rubrum isolate and one T. mentagrophytes isolate, were identified and submitted to the American Type Culture Collection (ATCC) for inclusion as reference strains. Ranges encompassing 95.2 to 97.9% of all data points for all seven drugs were established. PMID:17050812

A bioactivity guided study on the antibacterial activity of Hertia cheirifolia L. extracts.

PubMed

Majouli, Kaouther; Hamdi, Assia; Msaada, Kamel; Kenani, Abderraouf

2017-05-01

This study was carried out with the objective to investigate the antibacterial activity of Hertia cheirifolia L. extracts against Gram-positive and Gram-negative strains including Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Bacillus licheniformis, Esherichia coli (ATCC 8739), Pseudomonas aeruginosa (ATCC 9027), Salmonella enterica (CIP 8039) and Salmonella typhimirium. The results of this antibacterial screening showed that the ethyl acetate (EtOAc) extracts had the best activity against the tested microorganisms. A bioassay-oriented fractionation approach for the more active extract (roots ethyl acetate extract) led to the obtaining five sub-fractions. Furthermore, these sub-fractions were also tested for antimicrobial activity and the best results were obtained for the roots EtOAc sub-fraction (C) with MICs values between 0.039 and 0.156 mg/mL. Reversed-phase high performance liquid chromatography (RP-HPLC) analysis indicated that the major phenolic components of active (EtOAc) extracts and sub-fraction (C) are fisetin hydrate (82.06%), trans cinnamic acid (63.66%), gallic acid (38.97%) and myricetin (20.92%). These results may help to improve these natural antibacterial substances that could serve as selective agents for bacterial diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enterococcus caccae sp. nov., isolated from human stools.

PubMed

Carvalho, Maria da Glória S; Shewmaker, P Lynn; Steigerwalt, Arnold G; Morey, Roger E; Sampson, A J; Joyce, Kevin; Barrett, Timothy J; Teixeira, Lucia M; Facklam, Richard R

2006-07-01

The National Antimicrobial Resistance Monitoring System Laboratory at the Centers for Disease Control and Prevention (CDC) isolated two enterococcus-like strains that were referred to the CDC Streptococcus Laboratory for further identification. The isolates were recovered from human stool samples collected on different occasions from the same individual in Portland (OR, USA) in July 2000. Conventional physiological tests distinguished these strains from all known species of enterococci. Analyses of whole-cell-protein electrophoretic profiles showed the same unique profile for the two isolates, being most similar those of Enterococcus moraviensis and Enterococcus haemoperoxidus albeit not close enough to allow conclusive inclusion in any enterococcal species. Both isolates gave positive results in tests using the AccuProbe Enterococcus genetic probe, and Lancefield extracts reacted with CDC group D antiserum. Comparative 16S rRNA gene sequencing studies also revealed that these strains were closely related to the species E. moraviensis (99.6 % identity). The results of DNA-DNA relatedness experiments confirmed that these strains represented a single novel taxon. The highest level of DNA-DNA relatedness found between the novel taxon and any of the currently recognized species of Enterococcus was 32 %, for both E. moraviensis and E. haemoperoxidus. On the basis of this evidence, it is proposed that these stool isolates constitute a novel species, for which the name Enterococcus caccae sp. nov. is proposed. The type strain is 2215-02(T) (=SS-1777(T)=ATCC BAA-1240(T)=CCUG 51564(T)).

Composition and potency characterization of Mycobacterium avium subsp. paratuberculosis purified protein derivatives

USDA-ARS?s Scientific Manuscript database

Mycobacterium avium subsp. paratuberculosis (MAP) purified protein derivatives (PPDs) are immunologic reagents prepared from cultured filtrates of the type strain ATCC 19698. Traditional production consists of floating culture incubation at 37oC, organism inactivation by autoclaving, coarse filtrat...

Koserella trabulsii, a new genus and species of Enterobacteriaceae formerly known as Enteric Group 45.

PubMed Central

Hickman-Brenner, F W; Huntley-Carter, G P; Fanning, G R; Brenner, D J; Farmer, J J

1985-01-01

The name Koserella trabulsii is proposed for a group of Enterobacteriaceae formerly called Enteric Group 45. This group consists of 12 strains that were originally identified as atypical Hafnia alvei. K. trabulsii strains were negative for indole production, Voges-Proskauer, H2S production, urea hydrolysis, phenylalanine deaminase, and acid production from glycerol, lactose, sucrose, and D-sorbitol; they were positive for methyl red, citrate (Simmons), lysine and ornithine decarboxylases, arginine dihydrolase (negative in 1 to 2 days and positive in 3 to 7 days), and acid production from cellobiose and melibiose; and they were resistant to the Hafnia-specific bacteriophage of Guinée and Valkenburg. They were tested for DNA relatedness by the hydroxyapatite method with 32PO4-labeled DNA from the designated type strain (CDC 3349-72, ATCC 35313). The 12 strains were 87 to 99% related in 60 degrees C reactions. Relatedness of K. trabulsii to 71 DNA hybridization reference strains of representative species of Enterobacteriaceae was 4 to 37%. It was 15 to 16% related to H. alvei. All strains were susceptible to nalidixic acid, sulfadiazine, gentamicin, kanamycin, and chloramphenicol, and 83% were susceptible to nalidixic acid, sulfadiazine, gentamicin, kanamycin, and chloramphenicol, and 83% were susceptible to tetracycline. Most of the strains were resistant or intermediate to penicillin, ampicillin, carbenicillin, colistin, and cephalothin. Five of the strains were isolated from wounds, three were from the respiratory tract, and one each was from a stool, knee fluid, water, and an unknown source. The clinical significance of this organism is not known; therefore, future studies should focus on its isolation and its relationship to human disease. PMID:3968202

Screening of lactic acid bacteria from vacuum packaged beef for antimicrobial activity

PubMed Central

Oliveira, Roseane B. P.; de L. Oliveira, Afonso; Glória, M. Beatriz A.

2008-01-01

The objective of this study was to isolate lactic acid bacteria (LAB) from vacuum packaged beef and to investigate their antagonist activity. LAB mean counts of 5.19 log cfu/cm2 were obtained from five samples of vacuum packaged beef. Two hundred isolates were selected and screened for the inhibitory effect on five ATCC reference Lactobacillus strains. Thirty six isolates showed activity in the agar spot test against at least two of the indicator strains. However, only six cell free supernatants (CFS) from these isolates exhibited activity against the indicator strains using the well-diffusion test and conditions that eliminated the effects of organic acids and hydrogen peroxide. L. acidophilus was the most sensitive indicator tested, whereas L. plantarum and L. fermentum were the most resistant ones. Identification by MIDI system indicated that these LAB isolates were Lactococcus lactis subsp. cremoris, Pediococcus acidilactici, Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus casei GC subgroup A. The antagonistic factors produced by most of these LAB against L. acidophilus were resistant to heat treatment (100°C for 10 min) and stable over a wide pH range (4.0 to 9.0). These data suggest that these isolates could be used as promising hurdles aiming increased safety and extended shelf life of meat products. PMID:24031232

[Effect of Pseudomonas aeruginosa exometabolites on planktonic and biofilm cultures of Escherichia coli].

PubMed

Kuznetsova, M V; Karpunina, T I; Maslennikova, I L; Nesterova, L Iu; Demakov, V A

2012-01-01

Study the effect of P. aeruginosa exometabolites on planktonic and biofilm cultures of bioluminescent E. coli strain. E. coli K12 TG1 (pF1 lux+ Ap(r)) recombinant bioluminescent strain, P. aeruginosa ATCC 27853 reference strain and 2 nosocomial isolates were used. Pyocyanin and pyoverdin content in supernatant of P. aeruginosa over-night cultures was evaluated according to E. Deziel et al. (2001). Planktonic and biofilm cultures of E. coli were obtained in 96-well plates (LB, statically, 37 degrees C), optical density of plankton, film biomass (OD600, OD580) and bioluminescence in plankton and biofilm were evaluated in microplate reader Infiniti M200 (Tecan, Austria). P. aeruginosa exometabolites increased the duration of lag-phase in E. coli, and short term exposition inhibited luminescence of planktonic cells. These effects are determined by bactericidal action ofpyocyanin and pyoverdin. Supernatants ofover-night cultures of P. aeruginosa inhibit formation of biofilm and disrupt the formed biofilm of E. coli. Effect of pyocyanin and pyoverdin on these processes is not established, other factors may have higher significance. Bioluminescence of E. coli K12 TGI that reflects the energetic status of the cell allows to evaluate and prognose the character of coexistence of P. aeruginosa in combined with E. coli planktonic and biofilm culture.

Mortalities of Eastern and Pacific oyster Larvae caused by the pathogens Vibrio coralliilyticus and Vibrio tubiashii.

PubMed

Richards, Gary P; Watson, Michael A; Needleman, David S; Church, Karlee M; Häse, Claudia C

2015-01-01

Vibrio tubiashii is reported to be a bacterial pathogen of larval Eastern oysters (Crassostrea virginica) and Pacific oysters (Crassostrea gigas) and has been associated with major hatchery crashes, causing shortages in seed oysters for commercial shellfish producers. Another bacterium, Vibrio coralliilyticus, a well-known coral pathogen, has recently been shown to elicit mortality in fish and shellfish. Several strains of V. coralliilyticus, such as ATCC 19105 and Pacific isolates RE22 and RE98, were misidentified as V. tubiashii until recently. We compared the mortalities caused by two V. tubiashii and four V. coralliilyticus strains in Eastern and Pacific oyster larvae. The 50% lethal dose (LD50) of V. coralliilyticus in Eastern oysters (defined here as the dose required to kill 50% of the population in 6 days) ranged from 1.1 × 10(4) to 3.0 × 10(4) CFU/ml seawater; strains RE98 and RE22 were the most virulent. This study shows that V. coralliilyticus causes mortality in Eastern oyster larvae. Results for Pacific oysters were similar, with LD50s between 1.2 × 10(4) and 4.0 × 10(4) CFU/ml. Vibrio tubiashii ATCC 19106 and ATCC 19109 were highly infectious toward Eastern oyster larvae but were essentially nonpathogenic toward healthy Pacific oyster larvae at dosages of ≥1.1 × 10(4) CFU/ml. These data, coupled with the fact that several isolates originally thought to be V. tubiashii are actually V. coralliilyticus, suggest that V. coralliilyticus has been a more significant pathogen for larval bivalve shellfish than V. tubiashii, particularly on the U.S. West Coast, contributing to substantial hatchery-associated morbidity and mortality in recent years. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Proteome Analyses of Strains ATCC 51142 and PCC 7822 of the Diazotrophic Cyanobacterium Cyanothece sp under Culture Conditions Resulting in Enhanced H-2 Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aryal, Uma K.; Callister, Stephen J.; Mishra, Sujata

2013-02-01

Cultures of the cyanobacterial genus Cyanothece have been shown to produce high levels of biohydrogen. These strains are diazotrophic and undergo pronounced diurnal cycles when grown under N2-fixing conditions in light-dark cycles. We seek to better understand the way in which proteins respond to these diurnal changes and we performed quantitative proteome analysis of Cyanothece ATCC 51142 and PCC 7822 grown under 8 different nutritional conditions. Nitrogenase expression was limited to N2-fixing conditions, and in the absence of glycerol, nitrogenase gene expression was linked to the dark period. However, glycerol induced expression of nitrogenase during part of the light period,more » together with cytochrome c oxidase (Cox), glycogen phosphorylase (Glp), and glycolytic and pentose-phosphate pathway (PPP) enzymes. This indicated that nitrogenase expression in the light was facilitated via higher respiration and glycogen breakdown. Key enzymes of the Calvin cycle were inhibited in Cyanothece ATCC 51142 in the presence of glycerol under H2 producing conditions, suggesting a competition between these sources of carbon. However, in Cyanothece PCC 7822, the Calvin cycle still played a role in cofactor recycling during H2 production. Our data comprise the first comprehensive profiling of proteome changes in Cyanothece PCC 7822, and allows an in-depth comparative analysis of major physiological and biochemical processes that influence H2-production in both the strains. Our results revealed many previously uncharacterized proteins that may play a role in nitrogenase activity and in other metabolic pathways and may provide suitable targets for genetic manipulation that would lead to improvement of large scale H2 production.« less

Dinitrogenase-Driven Photobiological Hydrogen Production Combats Oxidative Stress in Cyanothece sp. Strain ATCC 51142

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sadler, Natalie C.; Bernstein, Hans C.; Melnicki, Matthew R.

ABSTRACT Photobiologically synthesized hydrogen (H 2) gas is carbon neutral to produce and clean to combust, making it an ideal biofuel.Cyanothecesp. strain ATCC 51142 is a cyanobacterium capable of performing simultaneous oxygenic photosynthesis and H 2production, a highly perplexing phenomenon because H 2evolving enzymes are O 2sensitive. We employed a system-levelin vivochemoproteomic profiling approach to explore the cellular dynamics of protein thiol redox and how thiol redox mediates the function of the dinitrogenase NifHDK, an enzyme complex capable of aerobic hydrogenase activity. We found that NifHDK responds to intracellular redox conditions and may act as an emergency electron valve tomore » prevent harmful reactive oxygen species formation in concert with other cell strategies for maintaining redox homeostasis. These results provide new insight into cellular redox dynamics useful for advancing photolytic bioenergy technology and reveal a new understanding for the biological function of NifHDK. IMPORTANCEHere, we demonstrate that high levels of hydrogen synthesis can be induced as a protection mechanism against oxidative stress via the dinitrogenase enzyme complex inCyanothecesp. strain ATCC 51142. This is a previously unknown feature of cyanobacterial dinitrogenase, and we anticipate that it may represent a strategy to exploit cyanobacteria for efficient and scalable hydrogen production. We utilized a chemoproteomic approach to capture thein situdynamics of reductant partitioning within the cell, revealing proteins and reactive thiols that may be involved in redox sensing and signaling. Additionally, this method is widely applicable across biological systems to achieve a greater understanding of how cells navigate their environment and how redox chemistry can be utilized to alter metabolism and achieve homeostasis.« less

Acid tolerance and acid shock response of Escherichia coli O157:H7 and non-O157:H7 isolates provide cross protection to sodium lactate and sodium chloride.

PubMed

Garren, D M; Harrison, M A; Russell, S M

1998-02-01

The survival of Escherichia coli O157:H7 and non-O157:H7 due to an enhanced acid tolerance response (ATR), and enhanced acid shock response (ASR), or the stationary phase protective system when exposed to lactic acid and the resulting cross protection against increased concentration of sodium chloride and sodium lactate was studied. Escherichia coli O157:H7 isolates (1932 and 009) and a non-O157:H7 strain (ATCC 23716) were grown to stationary phase at 32 degrees C and O157:H7 to one of two treatments in an attempt to either acid shock or acid adapt the survivors. Acid shocked cells were exposed to lactic acid at pH 4.0. Acid-adapted cells were first exposed to a pH of 5.5 and then an acid challenge of pH 4.0. Sodium lactate (10%, 20%, or 30%) or sodium chloride (5%, 10%, or 15%) were added to a minimal glucose medium after the acidification treatment. When acid shocked and acid adapted isolate 932 and strain ATCC 23716 tolerated the elevated levels of sodium lactate, and the strain ATCC 23716 tolerated the elevated levels of sodium chloride. Acid adaption allowed isolate 932 to tolerate higher levels of sodium chloride; however, the acid shocking did not provide the same protection. Neither of the acid treatment provided increased tolerance to sodium chloride for isolate E009. Evidence of cross protection against acid and sodium chloride or acid and sodium lactate in E. coli O157:H7 could point to a need for further evaluation of whether these combinations of preservation means are sufficient to control this pathogen.

Altered Competitive Fitness, Antimicrobial Susceptibility, and Cellular Morphology in a Triclosan-Induced Small-Colony Variant of Staphylococcus aureus

PubMed Central

Forbes, Sarah; Latimer, Joe; Bazaid, Abdulrahman

2015-01-01

Staphylococcus aureus can produce small-colony variants (SCVs) that express various phenotypes. While their significance is unclear, SCV propagation may be influenced by relative fitness, antimicrobial susceptibility, and the underlying mechanism. We have investigated triclosan-induced generation of SCVs in six S. aureus strains, including methicillin-resistant S. aureus (MRSA). Parent strains (P0) were repeatedly passaged on concentration gradients of triclosan using a solid-state exposure system to generate P10. P10 was subsequently passaged without triclosan to generate X10. Susceptibility to triclosan and 7 antibiotics was assessed at all stages. For S. aureus ATCC 6538, SCVs were further characterized by determining microbicide susceptibility and competitive fitness. Cellular morphology was examined using electron microscopy, and protein expression was evaluated through proteomics. Triclosan susceptibility in all SCVs (which could be generated from 4/6 strains) was markedly decreased, while antibiotic susceptibility was significantly increased in the majority of cases. An SCV of S. aureus ATCC 6538 exhibited significantly increased susceptibility to all tested microbicides. Cross-wall formation was impaired in this bacterium, while expression of FabI, a target of triclosan, and IsaA, a lytic transglycosylase involved in cell division, was increased. The P10 SCV was 49% less fit than P0. In summary, triclosan exposure of S. aureus produced SCVs in 4/6 test bacteria, with decreased triclosan susceptibility but with generally increased antibiotic susceptibility. An SCV derived from S. aureus ATCC 6538 showed reduced competitive fitness, potentially due to impaired cell division. In this SCV, increased FabI expression could account for reduced triclosan susceptibility, while IsaA may be upregulated in response to cell division defects. PMID:26033734

Phyllobacterium salinisoli sp. nov., isolated from a Lotus lancerottensis root nodule in saline soil from Lanzarote.

PubMed

León-Barrios, Milagros; Ramírez-Bahena, Martha Helena; Igual, José M; Peix, Álvaro; Velázquez, Encarna

2018-04-01

A Gram-negative rod, designated strain LLAN61 T , was isolated from a root nodule of Lotus lancerottensis growing in a saline soil sample from Lanzarote (Canary Islands). The strain grew optimally at 0.5 % (w/v) NaCl and tolerated up to 3.5 %. The 16S rRNA gene sequence analysis showed that strain LLAN61 T belonged to genus Phyllobacterium and that Phyllobacteriumleguminum ORS 1419 T and Phyllobacteriummyrsinacearum IAM 13584 T are the closest related species with 97.93 and 97.86% similarity values, respectively. In the atpD phylogeny, P. leguminum ORS 1419 T and P. myrsinacearum ATCC 43591 T , sharing similarities of 87.6 and 85.8% respectively, were also the closest species to strain LLAN61 T . DNA-DNA hybridization showed an average value of 21 % between strain LLAN61 T and P. leguminum LMG 22833 T , and 6 % with P. myrsinacearum ATCC 43590 T . The predominant fatty acids were C19 : 0 cyclo ω8c and C18 : 1ω6c/C18 : 1ω7c (summed feature 8). The DNA G+C content was 58.0 mol%. Strain LLAN61 T differed from its closest relatives in some culture conditions and in assimilation of several carbon sources. Based upon the results of phylogeny, DNA-DNA hybridization, phenotypic tests and fatty acid analysis, this strain should be classified as a novel species of Phyllobacterium for which the name Phyllobacterium salinisoli sp. nov. is proposed (type strain LLAN61 T =LMG 30173 T = CECT 9417 T ).

Coaggregation between probiotic bacteria and caries-associated strains: an in vitro study.

PubMed

Twetman, Lisa; Larsen, Ulla; Fiehn, Nils-Erik; Stecksén-Blicks, Christina; Twetman, Svante

2009-01-01

To evaluate the in vitro abilities of probiotic bacteria derived from consumer products to coaggregate with caries-associated mutans streptococci. Six lactobacillus strains (L. acidophilus (CCUG 5917), L. plantarum 299v, L. rhamnosus GG and LB21, L. paracasei F19, L. reuteri PTA5289) were cultivated under anaerobic conditions at 37°C in Man Rogosa Sharpe (MSB) broth for 24 h. Four strains of human streptococci (S. mutans Ingbritt, S. mutans (ATCC 25175), S. mutans GS-5, S. sobrinus (ATCC 33478) were similarly grown in Brain Heart Infusion (BHI) broth. A gastrointestinal pathogen (Escherichia coli) was aerobically cultivated on BHI broth as a positive control. After incubation, the bacteria were aerobically harvested, washed, and suspended in 10 mmol/l phosphate-buffered saline (pH 7.2). The probiotic strains were characterized with the API 50 CH system to confirm their identity. Coaggregation was determined by spectrophotometry in mixtures and bacterial suspensions alone after 1, 2, 4, and 24 h and expressed as the aggregation ratio (%). All probiotic strains showed coaggregation abilities with the oral pathogens and the results were strain specific and dependent on time. S. mutans GS-5 exhibited a significantly higher ability to coaggregate with all the probiotic strains than the other mutans streptococci and E. coli. The differences among the probiotic strains were modest with L. acidophilus being the most prone and L. rhamnosus LB21 the least prone to coaggregate with the oral streptococci. The results demonstrated different abilities of lactobacilli-derived probiotic bacteria to coaggregate with selected oral streptococci. Aggregation assays may be a useful complement for screening of probiotic candidates with possible anti-caries properties.

Emendation of Propionibacterium acnes subsp. acnes (Deiko et al. 2015) and proposal of Propionibacterium acnes type II as Propionibacterium acnes subsp. defendens subsp. nov.

PubMed

McDowell, Andrew; Barnard, Emma; Liu, Jared; Li, Huiying; Patrick, Sheila

2016-12-01

Recently, it has been proposed that strains of Propionibacterium acnes from the type III genetic division should be classified as P. acnessubsp. elongatum subsp. nov., with strains from the type I and II divisions collectively classified as P. acnessubsp. acnes subsp. nov. Under such a taxonomic re-appraisal, we believe that types I and II should also have their own separate rank of subspecies. In support of this, we describe a polyphasic taxonomic study based on the analysis of publicly available multilocus and whole-genome sequence datasets, alongside a systematic review of previously published phylogenetic, genomic, phenotypic and clinical data. Strains of types I and II form highly distinct clades on the basis of multilocus sequence analysis (MLSA) and whole-genome phylogenetic reconstructions. In silico or digital DNA-DNA similarity values also fall within the 70-80 % boundary recommended for bacterial subspecies. Furthermore, we see important differences in genome content, including the presence of an active CRISPR/Cas system in type II strains, but not type I, and evidence for increasing linkage equilibrium within the separate divisions. Key biochemical differences include positive test results for β-haemolytic, neuraminidase and sorbitol fermentation activities with type I strains, but not type II. We now propose that type I strains should be classified as P. acnessubsp. acnes subsp. nov., and type II as P. acnessubsp. defendens subsp. nov. The type strain of P. acnessubsp. acnes subsp. nov. is NCTC 737T (=ATCC 6919T=JCM 6425T=DSM 1897T=CCUG 1794T), while the type strain of P. acnessubsp. defendens subsp. nov. is ATCC 11828 (=JCM 6473=CCUG 6369).

Identification by Subtractive Hybridization of a Novel Insertion Sequence Specific for Virulent Strains of Porphyromonas gingivalis

PubMed Central

Sawada, Koichi; Kokeguchi, Susumu; Hongyo, Hiroshi; Sawada, Satoko; Miyamoto, Manabu; Maeda, Hiroshi; Nishimura, Fusanori; Takashiba, Shogo; Murayama, Yoji

1999-01-01

Subtractive hybridization was employed to isolate specific genes from virulent Porphyromonas gingivalis strains that are possibly related to abscess formation. The genomic DNA from the virulent strain P. gingivalis W83 was subtracted with DNA from the avirulent strain ATCC 33277. Three clones unique to strain W83 were isolated and sequenced. The cloned DNA fragments were 885, 369, and 132 bp and had slight homology with only Bacillus stearothermophilus IS5377, which is a putative transposase. The regions flanking the cloned DNA fragments were isolated and sequenced, and the gene structure around the clones was revealed. These three clones were located side-by-side in a gene reported as an outer membrane protein. The three clones interrupt the open reading frame of the outer membrane protein gene. This inserted DNA, consisting of three isolated clones, was designated IS1598, which was 1,396 bp (i.e., a 1,158-bp open reading frame) in length and was flanked by 16-bp terminal inverted repeats and a 9-bp duplicated target sequence. IS1598 was detected in P. gingivalis W83, W50, and FDC 381 by Southern hybridization. All three P. gingivalis strains have been shown to possess abscess-forming ability in animal models. However, IS1598 was not detected in avirulent strains of P. gingivalis, including ATCC 33277. The IS1598 may interrupt the synthesis of the outer membrane protein, resulting in changes in the structure of the bacterial outer membrane. The IS1598 isolated in this study is a novel insertion element which might be a specific marker for virulent P. gingivalis strains. PMID:10531208

Development of an accumulation assay and evaluation of the effects of efflux pump inhibitors on the retention of chlorhexidine digluconate in Pseudomonas aeruginosa and Staphylococcus aureus.

PubMed

Mombeshora, Molly; Mukanganyama, Stanley

2017-07-26

Chlorhexidine digluconate (CHG) is used as a disinfectant. The emergence of pathogens resistant to the biocide raises health concern. Information on specific efflux mechanisms utilised by bacteria to confer reduced susceptibility to the biocide, may be used to develop ways of preventing the efflux of the biocide from nosocomial pathogens resulting in higher disinfection activity. The aim of the study was to evaluate the role of ATP-binding cassette transporters on the transport of CHG in bacteria. Clinical strains of Pseudomonas aeruginosa, Staphylococcus aureus and their respective laboratory strains ATCC 27853 and ATCC 9144 were used for susceptibility tests. The minimum inhibitory concentration (MIC) of CHG with or without an efflux pump inhibitor [reserpine or carbonyl cyanide m-chlorophenylhydrazone (CCCP)] was determined using the broth microdilution method. A spectrophotometric method to quantify the amount of chlorhexidine in a sample was developed, validated and used to quantify CHG within P. aeruginosa and S. aureus cells. In the presence of reserpine, the MIC of CHG against the clinical strains of P. aeruginosa and S. aureus decreased from 6.3 to 3.2 µg/ml but showed no change against both ATCC isolates. The MIC of CHG in the presence of CCCP for both strains of P. aeruginosa remained unchanged but showed a reduction for both isolates of S. aureus. The suitability of the spectrophotometric method developed for quantifying the amount of CHG accumulated in microbial cells was validated and used successfully to quantify CHG accumulated within bacterial cells. The spectrophotometric determination of CHG within microbial cells may be used to quantify CHG in microbial cells. Only the clinical strain of P. aeruginosa showed significant efflux of CHG suggesting the participation of efflux transporters in the pumping out of CHG from this isolate. The use of efflux pump inhibitors together with the biocide may be explored to preventing the efflux of the biocide from P. aeruginosa resulting in order to increase disinfection activity.

Oxygen-Inducible Conversion of Lactate to Acetate in Heterofermentative Lactobacillus brevis ATCC 367.

PubMed

Guo, Tingting; Zhang, Li; Xin, Yongping; Xu, ZhenShang; He, Huiying; Kong, Jian

2017-11-01

Lactobacillus brevis is an obligatory heterofermentative lactic acid bacterium that produces high levels of acetate, which improve the aerobic stability of silages against deterioration caused by yeasts and molds. However, the mechanism involved in acetate accumulation has yet to be elucidated. Here, experimental evidence indicated that aerobiosis resulted in the conversion of lactate to acetate after glucose exhaustion in L. brevis ATCC 367 (GenBank accession number NC_008497). To elucidate the conversion pathway, in silico analysis showed that lactate was first converted to pyruvate by the reverse catalytic reaction of lactate dehydrogenase (LDH); subsequently, pyruvate conversion to acetate might be mediated by pyruvate dehydrogenase (PDH) or pyruvate oxidase (POX). Transcriptional analysis indicated that the pdh and pox genes of L. brevis ATCC 367 were upregulated 37.92- and 18.32-fold, respectively, by oxygen and glucose exhaustion, corresponding to 5.32- and 2.35-fold increases in the respective enzyme activities. Compared with the wild-type strain, the transcription and enzymatic activity of PDH remained stable in the Δ pox mutant, while those of POX increased significantly in the Δ pdh mutant. More lactate but less acetate was produced in the Δ pdh mutant than in the wild-type and Δ pox mutant strains, and more H 2 O 2 (a product of the POX pathway) was produced in the Δ pdh mutant. We speculated that the high levels of aerobic acetate accumulation in L. brevis ATCC 367 originated mainly from the reuse of lactate to produce pyruvate, which was further converted to acetate by the predominant and secondary functions of PDH and POX, respectively. IMPORTANCE PDH and POX are two possible key enzymes involved in aerobic acetate accumulation in lactic acid bacteria (LAB). It is currently thought that POX plays the major role in aerobic growth in homofermentative LAB and some heterofermentative LAB, while the impact of PDH remains unclear. In this study, we reported that both PDH and POX worked in the aerobic conversion of lactate to acetate in L. brevis ATCC 367, in dominant and secondary roles, respectively. Our findings will further develop the theory of aerobic metabolism by LAB. Copyright © 2017 American Society for Microbiology.

Evaluating the formulae for integrated lethality in ethylene oxide sterilization using six different endospore forming strains of bacteria, and comparisons of integrated lethality for ethylene oxide and steam systems.

PubMed

Mosley, Gregg A; Gillis, John R; Krushefski, Garrett

2005-01-01

Bacterial endospores from six different species of bacteria were exposed to a spectrum of ethylene oxide (EtO) sterilizing conditions. Temperature was varied from 40 to 60 degrees C and the ethylene oxide concentration was varied from 300 to 750 mg/L. Relative humidity was maintained at 60+/-10% RH. The fraction negative procedure was used to determine the D value for each of the test conditions. Bacterial species tested included Bacillus atrophaeus ATCC # 9372, Bacillus smithii ATCC # 51232, Bacillus subtilis "5230" ATCC # 35021, Bacillus subtilis, DSM # 4181, Bacillus pumilus ATCC # 27142, and Geobacillus stearothermophilus ATCC # 7953. All spore preparations were inoculated on filter paper strips packaged in blue, sterilizable glassine pouches. G. stearothermophilus was the least resistant organism tested. The most resistant organisms tested were B. atrophaeus and B. subtilis "5230". The B. subtilis "5230" strain was slightly more resistant than B. atrophaeus at conditions of 54C and EtO concentrations of 400, 600, and 750 mg/L, as well as at 60C/750mg/L EtO. The other species were between these extremes. This empirical data allowed the application of the recently published formula for converting D values from one set of conditions to another and evaluations of accuracy. The measured D values also allowed the determination of Z values based on temperature variations. These formulae, when applied to process temperatures independent of gas concentration, result in a Z value of approximately 32 degrees C that appears to be similar for all species tested. These data support the application of the previously published formulae 1-6 and allow the same approach to integrated lethality for ethylene oxide processes as is commonly applied to steam sterilization. A review of steam sterilization and related principles was conducted for comparison of integrated lethality for these two methods of sterilization. Errors associated with D values, Z values, extrapolation, and integrated lethality for both methods of sterilization are discussed.

Macroalgae Extracts From Antarctica Have Antimicrobial and Anticancer Potential

PubMed Central

Martins, Rosiane M.; Nedel, Fernanda; Guimarães, Victoria B. S.; da Silva, Adriana F.; Colepicolo, Pio; de Pereira, Claudio M. P.; Lund, Rafael G.

2018-01-01

Background: Macroalgae are sources of bioactive compounds due to the large number of secondary metabolites they synthesize. The Antarctica region is characterized by extreme weather conditions and abundant aggregations of macroalgae. However, current knowledge on their biodiversity and their potential for bio-prospecting is still fledging. This study evaluates the antimicrobial and cytotoxic activity of different extracts of four macroalgae (Cystosphaera jacquinotii, Iridaea cordata, Himantothallus grandifolius, and Pyropia endiviifolia) from the Antarctic region against cancer and non-cancer cell lines. Methods: The antimicrobial activity of macroalgae was evaluated by the broth microdilution method. Extracts were assessed against Staphylococcus aureus ATCC 19095, Enterococcus faecalis ATCC 4083, Escherichia coli ATCC29214, Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 62342, and the clinical isolates from the human oral cavity, namely, C. albicans (3), C. parapsilosis, C. glabrata, C. lipolytica, and C. famata. Cytotoxicity against human epidermoid carcinoma (A-431) and mouse embryonic fibroblast (NIH/3T3) cell lines was evaluated with MTT colorimetric assay. Results: An ethyl acetate extract of H. grandifolius showed noticeable antifungal activity against all fungal strains tested, including fluconazole-resistant samples. Cytotoxicity investigation with a cancer cell line revealed that the ethyl acetate extract of I. cordata was highly cytotoxic against A-431 cancer cell line, increasing the inhibitory ratio to 91.1 and 95.6% after 24 and 48 h exposure, respectively, for a concentration of 500 μg mL−1. Most of the algal extracts tested showed little or no cytotoxicity against fibroblasts. Conclusion: Data suggest that macroalgae extracts from Antarctica may represent a source of therapeutic agents. HIGHLIGHTS Different macroalgae samples from Antarctica were collected and the lyophilized biomass of each macroalgae was extracted sequentially with different solventsThe antimicrobial and anticancer potential of macroalgae extracts were evaluatedEthyl acetate extract of H. grandifolius showed noticeable antifungal activity against all the fungal strains tested, including fluconazole-resistant samplesEthyl acetate extract of I. cordata was highly cytotoxic against the A-431 cancer cell lineMost of the algal extracts tested showed little or no cytotoxicity against normal cell lines PMID:29568291

Oxygen-Inducible Conversion of Lactate to Acetate in Heterofermentative Lactobacillus brevis ATCC 367

PubMed Central

Guo, Tingting; Zhang, Li; Xin, Yongping; Xu, ZhenShang; He, Huiying

2017-01-01

ABSTRACT Lactobacillus brevis is an obligatory heterofermentative lactic acid bacterium that produces high levels of acetate, which improve the aerobic stability of silages against deterioration caused by yeasts and molds. However, the mechanism involved in acetate accumulation has yet to be elucidated. Here, experimental evidence indicated that aerobiosis resulted in the conversion of lactate to acetate after glucose exhaustion in L. brevis ATCC 367 (GenBank accession number NC_008497). To elucidate the conversion pathway, in silico analysis showed that lactate was first converted to pyruvate by the reverse catalytic reaction of lactate dehydrogenase (LDH); subsequently, pyruvate conversion to acetate might be mediated by pyruvate dehydrogenase (PDH) or pyruvate oxidase (POX). Transcriptional analysis indicated that the pdh and pox genes of L. brevis ATCC 367 were upregulated 37.92- and 18.32-fold, respectively, by oxygen and glucose exhaustion, corresponding to 5.32- and 2.35-fold increases in the respective enzyme activities. Compared with the wild-type strain, the transcription and enzymatic activity of PDH remained stable in the Δpox mutant, while those of POX increased significantly in the Δpdh mutant. More lactate but less acetate was produced in the Δpdh mutant than in the wild-type and Δpox mutant strains, and more H2O2 (a product of the POX pathway) was produced in the Δpdh mutant. We speculated that the high levels of aerobic acetate accumulation in L. brevis ATCC 367 originated mainly from the reuse of lactate to produce pyruvate, which was further converted to acetate by the predominant and secondary functions of PDH and POX, respectively. IMPORTANCE PDH and POX are two possible key enzymes involved in aerobic acetate accumulation in lactic acid bacteria (LAB). It is currently thought that POX plays the major role in aerobic growth in homofermentative LAB and some heterofermentative LAB, while the impact of PDH remains unclear. In this study, we reported that both PDH and POX worked in the aerobic conversion of lactate to acetate in L. brevis ATCC 367, in dominant and secondary roles, respectively. Our findings will further develop the theory of aerobic metabolism by LAB. PMID:28842545

Genome Sequences for Multiple Clavibacter Strains from Different Subspecies

PubMed Central

Yuan, Xiaoli (Kat)

2017-01-01

ABSTRACT The Gram-positive genus Clavibacter harbors economically important plant pathogens infecting a variety of agricultural crops, such as potato, tomato, corn, barley, etc. Here, we report five new genome sequences, those of strains CFIA-Cs3N, CFIA-CsR14, LMG 3663T, LMG 7333T, and ATCC 33566T, from different subspecies of Clavibacter michiganensis. All these genomic data will be used for reclassification and niche-adapted feature comparisons. PMID:28935724

Candida tropicalis biofilm inhibition by ZnO nanoparticles and EDTA.

PubMed

Jothiprakasam, Vinoth; Sambantham, Murugan; Chinnathambi, Stalin; Vijayaboopathi, Singaravel

2017-01-01

Biofilm of Candida tropicalis denote as a complex cellular congregation with major implication in pathogenesis. This lifestyle of fungus as a biofilm can inhibit immune system and antifungal therapy in treatment of infectious disease especially medical device associated chronic disease. In this study effects of Zinc Oxide (ZnO) nanoparticles and EDTA were evaluated on C. tropicalis biofilm by using different techniques. ZnO nanoparticles were synthesized from Egg albumin. To assay the formation of biofilm of yeast cells like Fluconazole-susceptible C. tropicalis (ATCC 13,803) and fluconazole-resistant standard strains of C. tropicalis (ATCC 750) were grown in 24 well plates and antifungal effect of ZnO and EDTA were evaluated on C. tropicalis biofilm using ATP bioluminescence and tetrasodium salt (XTT) reduction assays. Synthesized ZnO NPs and EDTA had effective antifungal properties at the concentration of 5.2, 8.6μg/ml for Fluconazole susceptible strain and 5.42, 10.8μg/ml Fluconazole resistant strains of C. tropicalis biofilms compared to fluconazole drug. In present study we conclude, ZnO considered as a new agent in field of prevention C. tropicalis biofilms especially biofilms formed surface of medical device. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multiplex-touchdown PCR assay for the detection and genotyping of Helicobacter pylori from artificially contaminated sheep milk.

PubMed

Quaglia, N C; Normanno, G; Dambrosio, A; Celano, G V; Parisi, A; Firinu, A; Buonavoglia, C

2005-10-01

Helicobacter pylori (Hp) is an organism commonly present worldwide in the human population, sometimes causing serious illnesses such as duodenal and gastric ulcers, adenocarcinoma of the stomach, and low-grade B-cell mucosa-associated lymphoid tissue lymphoma of the stomach. This article describes a multiplex-touchdown PCR method for the identification and genotyping (vacA-s1/m1, sl/m2, and s2/m2-and cagA genes) of Hp directly from sheep milk artificially contaminated with Hp strains from human gastric biopsies and with Hp ATCC 43504. The strains from humans carried sl/m2 cagA+ and s2/m2 cagA allelic combinations, while the ATCC strains carried an sl/ml cagA+ allelic combination. The technique showed a sensitivity of 15 CFU/ml for species identification and of 1,500 CFU/ml for the detection of genes encoding for VacA and CagA. It has proven to be specific and rapid, and the authors suggest that it be used as a rapid screening method to ensure that sheep milk is uncontaminated with this organism.

Genome Sequences of 12 Cluster AN Arthrobacter Phages

PubMed Central

Lee-Soety, Julia Y.; Bhatt, Shantanu; Adair, Tamarah L.; Bonilla, J. Alfred; Klyczek, Karen K.; Harrison, Melinda; Garlena, Rebecca A.; Bowman, Charles A.; Russell, Daniel A.; Jacobs-Sera, Deborah

2017-01-01

ABSTRACT Twelve siphoviral phages isolated using Arthrobacter sp. strain ATCC 21022 were sequenced. The phages all have relatively small genomes, ranging from 15,319 to 15,556 bp. All 12 phages are closely related to previously described cluster AN Arthrobacter phages. PMID:29122859

Spectrum of bacteriocin activity of Lactobacillus plantarum BS and fingerprinting by RAPD-PCR.

PubMed

Elegado, Francisco B; Guerra, Marie Antonette Ruth V; Macayan, Rommel A; Mendoza, Helen A; Lirazan, Marcelina B

2004-08-15

The spectrum of antimicrobial activity of Lactobacillus plantarum BS against representative bacterial species was established through deferred assay and 'spot-on-lawn' assay using actively growing cells and partially purified bacteriocin extract, respectively. Only lactobacilli, pediococci, enterococci, bacilli and Listeria were inhibited from the test microorganisms. Slight bacteriocinogenic activity through 'spot-on-lawn' assay was detected against Staphylococcus aureus and Escherichia coli O157:H7. Random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) analysis was used to compare the fingerprint of L. plantarum BS with other strains of L. plantarum. Using the 16S rRNA-based primer, P32, the bacteriocinogenic isolate exhibited identical RAPD-PCR fingerprints to L. plantarum ATCC 14917. Dendrograms derived from the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) were constructed to show the similarity relationships among the investigated strains based on RAPD-PCR analysis. Bands differentiating L. plantarum BS from L. plantarum ATCC 14917 were also identified by varying the annealing temperature.

Molecular discrimination of lactobacilli used as starter and probiotic cultures by amplified ribosomal DNA restriction analysis.

PubMed

Roy, D; Sirois, S; Vincent, D

2001-04-01

Lactic acid bacteria such as Lactobacillus helveticus, L. delbrueckii subsp. delbrueckii, L. delbrueckii subsp. lactis, L. delbrueckii subsp. bulgaricus, L. acidophilus, and L. casei related taxa which are widely used as starter or probiotic cultures can be identified by amplified ribosomal DNA restriction analysis (ARDRA). The genetic discrimination of the related species belonging to these groups was first obtained by PCR amplifications by using group-specific or species-specific 16S rDNA primers. The numerical analysis of the ARDRA patterns obtained by using CfoI, HinfI, Tru9I, and ScrFI was an efficient typing tool for identification of species of the L. acidophilus and L. casei complex. ARDRA by using CfoI was a reliable method for differentiation of L. delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis. Finally, strains ATCC 393 and ATCC 15820 exhibited unique ARDRA patterns with CfoI and Tru9I restriction enzymes as compared with the other strains of L. casei, L. paracasei, and L. rhamnosus.

Identification and Characterization of Two Novel Clostridial Bacteriocins, Circularin A and Closticin 574

PubMed Central

Kemperman, Robèr; Kuipers, Anneke; Karsens, Harma; Nauta, Arjen; Kuipers, Oscar; Kok, Jan

2003-01-01

Two novel antibacterial peptides of clostridial species were purified, N-terminally sequenced, and characterized. Moreover, their structural genes were identified. Closticin 574 is an 82-amino-acid bacteriocin produced by Clostridium tyrobutyricum ADRIAT 932. The supernatant of the producing strain showed a high level of activity against the indicator strain C. tyrobutyricum. The protein is synthesized as a preproprotein that is possibly secreted via the general secretion pathway, after which it is hydrolyzed at an Asp-Pro site. Circularin A is produced by Clostridium beijerinckii ATCC 25752 as a prepeptide of 72 amino acids. Cleavage of the prepeptide between the third leucine and fourth valine residues followed by a head-to-tail ligation between the N and C termini creates a circular antimicrobial peptide of 69 amino acids. The unusually small circularin A leader peptide of three amino acids is cleaved off in this process. The supernatant of C. beijerinckii ATCC 25752 showed a broad antibacterial activity range. PMID:12620847

Enzymatic dehalogenation of pentachlorophenol by extracts from Arthrobacter sp. strain ATCC 33790.

PubMed Central

Schenk, T; Müller, R; Mörsberger, F; Otto, M K; Lingens, F

1989-01-01

Arthrobacter sp. strain ATCC 33790 was grown with pentachlorophenol (PCP) as the sole source of carbon and energy. Crude extracts, which were prepared by disruption of the bacteria with a French pressure cell, showed no dehalogenating activity with PCP as the substrate. After sucrose density ultracentrifugation of the crude extract at 145,000 x g, various layers were found in the gradient. One yellow layer showed enzymatic conversion of PCP. One chloride ion was released per molecule of PCP. The product of the enzymatic conversion was tetrachlorohydroquinone. NADPH and oxygen were essential for this reaction. EDTA stimulated the enzymatic activity by 67%. The optimum pH for the enzyme activity was 7.5, and the temperature optimum was 25 degrees C. Enzymatic activity was also detected with 2,4,5-trichlorophenol, 2,3,4-trichlorophenol, 2,4,6-trichlorophenol, and 2,3,4,5-tetrachlorophenol as substrates, whereas 3,4,5-trichlorophenol, 2,4-dichlorophenol, 3,4-dichlorophenol, and 4-chlorophenol did not serve as substrates. PMID:2793827

Factors affecting the photoproduction of ammonia from dinitrogen and water by the cyanobacterium Anabaena sp. strain ATCC 33047.

PubMed

Ramos, J L; Guerrero, M G; Losada, M

1987-04-01

Synthesis of ammonia from dinitrogen and water by suspensions of Anabaena sp. Strain ATCC 33047 treated with the glutamine synthetase inhibitor L-methionine-D,L-sulfoximine is strictly dependent on light. Under otherwise optimal conditions, the yield of ammonia production is influenced by irradiance, as well as by the density, depth, and turbulence of the cell suspension. The interaction among these factors seems to determine the actual amount of light available to each single cell or filament in the suspension for the photoproduction process. Under convenient illumination, the limiting factor in the synthesis of ammonia seems to be the cellular nitrogenase activity level, but under limiting light conditions the limiting factor could, however, be the assimilatory power required for nitrogen fixation. Photosynthetic ammonia production from atmospheric nitrogen and water can operate with an efficiency of ca. 10% of its theoretical maximum, representing a remarkable process for the conversion of light energy into chemical energy.

A screening for antimicrobial activities of Caribbean herbal remedies

PubMed Central

2013-01-01

Background The TRAMIL program aims to understand, validate and expand health practices based on the use of medicinal plants in the Caribbean, which is a “biodiversity hotspot” due to high species endemism, intense development pressure and habitat loss. The antibacterial activity was examined for thirteen plant species from several genera that were identified as a result of TRAMIL ethnopharmacological surveys or were reported in ethnobotanical accounts from Puerto Rico. The aim of this study was to validate the traditional use of these plant species for the treatment of bacterial infections, such as conjunctivitis, fever, otitis media and furuncles. Methods An agar disc diffusion assay was used to examine five bacterial strains that are associated with the reported infections, including Staphylococcus saprophyticus (ATCC 15305), S. aureus (ATCC 6341), Escherichia coli (ATCC 4157), Haemophilus influenzae (ATCC 8142), Pseudomonas aeruginosa (ATCC 7700) and Proteus vulgaris (ATCC 6896), as well as the fungus Candida albicans (ATCC 752). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined for each of the extracts that showed inhibitory activity. Results The decoctions of Pityrogramma calomelanos, Tapeinochilus ananassae, and Syzygium jambos, as well as the juice of Gossypium barbadense, showed > 20% growth inhibition against several bacteria relative to the positive control, which was the antibiotic Streptomycin. Extracts with the best antimicrobial activities were S. jambos that showed MIC = 31 μg/mL and MBC = 1.0 mg/mL against P. vulgaris and T. ananassae that showed MIC = 15 μg/mL against S. aureus. Conclusion This report confirms the traditional use of P. calomelanos for the treatment of kidney infections that are associated with stones, as well as the antimicrobial and bactericidal effects of T. ananassae against P. vulgaris and S. saprophyticus and the effects of S. jambos against S. aureus and S. saprophyticus. PMID:23731467

Synthesis, Molecular Docking, and Antimycotic Evaluation of Some 3-Acyl Imidazo[1,2-a]pyrimidines.

PubMed

Gómez-García, Omar; Andrade-Pavón, Dulce; Campos-Aldrete, Elena; Ballinas-Indilí, Ricardo; Méndez-Tenorio, Alfonso; Villa-Tanaca, Lourdes; Álvarez-Toledano, Cecilio

2018-03-07

A series of 3-benzoyl imidazo[1,2- a ]pyrimidines, obtained from N -heteroarylformamidines in good yields, was tested in silico and in vitro for binding and inhibition of seven Candida species ( Candida albicans (ATCC 10231), Candida dubliniensis (CD36), Candida glabrata (CBS138), Candida guilliermondii (ATCC 6260), Candida kefyr , Candida krusei (ATCC 6358) and Candida tropicalis (MYA-3404)). To predict binding mode and energy, each compound was docked in the active site of the lanosterol 14α-demethylase enzyme (CYP51), essential for fungal growth of Candida species. Antimycotic activity was evaluated as the 50% minimum inhibitory concentration (MIC50) for the test compounds and two reference drugs, ketoconazole and fluconazole. All test compounds had a better binding energy (range: -6.11 to -9.43 kcal/mol) than that found for the reference drugs (range: 48.93 to -6.16 kcal/mol). In general, the test compounds showed greater inhibitory activity of yeast growth than the reference drugs. Compounds 4j and 4f were the most active, indicating an important role in biological activity for the benzene ring with electron-withdrawing substituents. These compounds show the best MIC50 against C. guilliermondii and C. glabrata, respectively. The current findings suggest that the 3-benzoyl imidazo[1,2- a ]pyrimidine derivatives, herein synthesized by an accessible methodology, are potential antifungal drugs.

A Candida guilliermondii lysine hyperproducer capable of elevated citric acid production.

PubMed

West, Thomas P

2016-05-01

A mutant of the yeast Candida guilliermondii ATCC 9058 exhibiting elevated citric acid production was isolated based upon its ability to overproduce lysine. This method involved the use of a solid medium containing a combination of lysine analogues to identify a mutant that produced a several-fold higher lysine level compared to its parent strain using glucose or glycerol as a carbon source. The mutant strain was also capable of producing more than a fivefold higher citric acid level on glycerol as a carbon source compared to its parent strain. It was concluded that the screening of yeast lysine hyperproducer strains could provide a rapid approach to isolate yeast citric acid hyperproducer strains.

Geobacter bemidjiensis sp. nov. and Geobacter psychrophilus sp. nov., two novel Fe(III)-reducing subsurface isolates

USGS Publications Warehouse

Nevin, Kelly P.; Holmes, Dawn E.; Woodard, Trevor L.; Hinlein, Erich S.; Ostendorf, David W.; Lovely, Derek R.

2005-01-01

Fe(III)-reducing isolates were recovered from two aquifers in which Fe(III) reduction is known to be important. Strain BemT was enriched from subsurface sediments collected in Bemidji, MN, USA, near a site where Fe(III) reduction is important in aromatic hydrocarbon degradation. Strains P11, P35T and P39 were isolated from the groundwater of an aquifer in Plymouth, MA, USA, in which Fe(III) reduction is important because of long-term inputs of acetate as a highway de-icing agent to the subsurface. All four isolates were Gram-negative, slightly curved rods that grew best in freshwater media. Strains P11, P35T and P39 exhibited motility via means of monotrichous flagella. Analysis of the 16S rRNA and nifD genes indicated that all four strains are δ-proteobacteria and members of the Geobacter cluster of the Geobacteraceae. Differences in phenotypic and phylogenetic characteristics indicated that the four isolates represent two novel species within the genus Geobacter. All of the isolates coupled the oxidation of acetate to the reduction of Fe(III) [iron(III) citrate, amorphous iron(III) oxide, iron(III) pyrophosphate and iron(III) nitrilotriacetate]. All four strains utilized ethanol, lactate, malate, pyruvate and succinate as electron donors and malate and fumarate as electron acceptors. Strain BemT grew fastest at 30 °C, whereas strains P11, P35T and P39 grew equally well at 17, 22 and 30 °C. In addition, strains P11, P35T and P39 were capable of growth at 4 °C. The names Geobacter bemidjiensis sp. nov. (type strain BemT=ATCC BAA-1014T=DSM 16622T=JCM 12645T) and Geobacter psychrophilus sp. nov. (strains P11, P35T and P39; type strain P35T=ATCC BAA-1013T=DSM 16674T=JCM 12644T) are proposed.

Porphyromonas gingivalis displays a competitive advantage over Aggregatibacter actinomycetemcomitans in co-cultured biofilm.

PubMed

Takasaki, K; Fujise, O; Miura, M; Hamachi, T; Maeda, K

2013-06-01

Biofilm formation occurs through the events of cooperative growth and competitive survival among multiple species. Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans are important periodontal pathogens. The aim of this study was to demonstrate competitive or cooperative interactions between these two species in co-cultured biofilm. P. gingivalis strains and gingipain mutants were cultured with or without A. actinomycetemcomitans. Biofilms formed on glass surfaces were analyzed by crystal violet staining and colony counting. Preformed A. actinomycetemcomitans biofilms were treated with P. gingivalis culture supernatants. Growth and proteolytic activities of gingipains were also determined. Monocultured P. gingivalis strains exhibited a range of biofilm-formation abilities and proteolytic activities. The ATCC33277 strain, noted for its high biofilm-formation ability and proteolytic activity, was found to be dominant in biofilm co-cultured with A. actinomycetemcomitans. In a time-resolved assay, A. actinomycetemcomitans was primarily the dominant colonizer on a glass surface and subsequently detached in the presence of increasing numbers of ATCC33277. Detachment of preformed A. actinomycetemcomitans biofilm was observed by incubation with culture supernatants from highly proteolytic strains. These results suggest that P. gingivalis possesses a competitive advantage over A. actinomycetemcomitans. As the required biofilm-formation abilities and proteolytic activities vary among P. gingivalis strains, the diversity of the competitive advantage is likely to affect disease recurrence during periodontal maintenance. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Methylene blue internalization and photodynamic action against clinical and ATCC Pseudomonas aeruginosa and Staphyloccocus aureus strains.

PubMed

Pereira, André Henrique Correia; Pinto, Juliana Guerra; Freitas, Mirian Aparecida Alves; Fontana, Letícia Corrêa; Pacheco Soares, Cristina; Ferreira-Strixino, Juliana

2018-06-01

Bacterial infections have been a major challenge to health. Increasing resistance to antimicrobial agents, according to World Health Organization, could be the major cause of death until 2050. Photodynamic therapy emerges as an alternative in microbial inactivation, due to its selectivity and to decreasing or dismissing antibiotic use. This study aimed at evaluating, in vitro, the internalization of the Methylene Blue and its photodynamic activity against a clinical and ATCC strain of Pseudomonas aeruginosa and Staphyloccocus aureus. Thus, the strains were incubated with MB in concentrations of 100, 300 e 500 μg/ml and then irradiated with a LED (±660 nm) at fluence of 10 and 25 J/cm 2 . The MB internalization was evaluated using a confocal microscope (Zeiss LSM 700), to capture the MB and the DAPI (for DNA staining). It was possible to observe that the MB was internalized by the bacterial cells, in all concentrations tested. The CFU/ml count demonstrated significant reduction (p ≤ 0,01) at the average 5.0 logs comparing with control group for the two species in all the tested concentrations. In conclusion, the strains tested were capable of internalizing the MB. PDT with MB was able to decrease the growth of the tested strains in vitro, being a promising alternative to the future treatment of infections caused by these species. Copyright © 2018 Elsevier B.V. All rights reserved.

Mycobacterium minnesotense sp. nov., a photochromogenic bacterium isolated from sphagnum peat bogs.

PubMed

Hannigan, Geoffrey D; Krivogorsky, Bogdana; Fordice, Daniel; Welch, Jacqueline B; Dahl, John L

2013-01-01

Several intermediate-growing, photochromogenic bacteria were isolated from sphagnum peat bogs in northern Minnesota, USA. Acid-fast staining and 16S rRNA gene sequence analysis placed these environmental isolates in the genus Mycobacterium, and colony morphologies and PCR restriction analysis patterns of the isolates were similar. Partial sequences of hsp65 and dnaJ1 from these isolates showed that Mycobacterium arupense ATCC BAA-1242(T) was the closest mycobacterial relative, and common biochemical characteristics and antibiotic susceptibilities existed between the isolates and M. arupense ATCC BAA-1242(T). However, compared to nonchromogenic M. arupense ATCC BAA-1242(T), the environmental isolates were photochromogenic, had a different mycolic acid profile and had reduced cell-surface hydrophobicity in liquid culture. The data reported here support the conclusion that the isolates are representatives of a novel mycobacterial species, for which the name Mycobacterium minnesotense sp. nov. is proposed. The type strain is DL49(T) (=DSM 45633(T) = JCM 17932(T) = NCCB 100399(T)).

Dentifrice Containing Extract of Rosmarinus officinalis Linn.: An Antimicrobial Evaluation.

PubMed

Valones, Marcela Agne Alves; Higino, Jane Sheila; Souza, Paulo Roberto Eleutério; Crovella, Sérgio; Caldas, Arnaldo de França; Carvalho, Alessandra de Albuquerque Tavares

2016-01-01

This study aimed to evaluate the antimicrobial activity of a dentifrice containing an alcoholic extract of rosemary on oral bacteria, compared to a commercially available herbal dentifrice. Standard strains of Streptococcus mutans (ATCC 25175), Streptococcus oralis (ATCC 9811) and Lactobacillus rhamnosus (ATCC 7469) were used, as well as different toothpastes based on rosemary (TR), on propolis (TH), triclosan (positive control) (TPC) and non-fluoridated dentifrice (negative control) (TNC). Bacteria were seeded in Petri dishes and paper discs soaked with dilutions of dentifrice placed on the plates. The inhibition halos were analyzed. It was observed that TR did not show statistical difference in relation to the TH to inhibit S. mutans and S. oralis, while TH was more active against L. rhamnosus. The toothpaste containing rosemary extract had the ability to inhibit the growth of S. mutans, S. oralis and L. rhamnosus, revealing an antimicrobial activity similar to commercially available toothpastes for inhibition of S. mutans and S. oralis.

Structural elucidation of a novel phosphoglycolipid isolated from six species of Halomonas.

PubMed

Giordano, Assunta; Vella, Filomena M; Romano, Ida; Gambacorta, Agata

2007-08-01

The structure of a new phosphoglycolipid from the halophilic Gram-negative bacteria Halomonas elongata ATCC 33173(T), Halomonas eurihalina ATCC 49336(T), Halomonas almeriensis CECT 7050(T), strain Sharm (AM238662), Halomonas halophila DSM 4770(T), and Halomonas salina ATCC 49509(T) was elucidated by NMR and mass spectroscopy studies. In all of the species examined, the polar lipid composition consisted of 1,2-diacylglycero-3-phosphorylethanolamine, 1,2-diacylglycero-3-phosphoryl-glycerol, bisphosphatidyl glycerol, and the new phosphoglycolipid PGL1. The structure of PGL1 was established to be (2-(alpha-D-glucopyranosyloxy)-3-hydroxy-propyl)-phosphatidyl diacylglycerol. C16:0;C18:1 and C16:0;C19:cyclopropane are the most abundant acyl chains linked to the phosphatidylglycerol moiety of each isolated PGL1. All of the species presenting the lipid PGL1 belong to Halomonas rRNA group 1, suggesting that the new phosphoglycolipid could be a chemotaxonomic marker of this phylogenetic group.