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

Dilli, S.; Garnett, J.L.

In a study of the mechanism of radiation-induced reactions with cellulose, the radiation chemistry of a number of simple crystalline sugars and polysaccharides was investigated. All solid sugars were irradiated in both air and vacuum to total doses of 10/sup 7/ and 10/sup 8/ rad in a Co/sup 60/ source at 1.25 megarad/hr. Examination of the gaseous products showed that irradiated cellobiose yields a relatively high hydrogen content, while amylose and amylopectin (amorphous) at doses of 10/sup 8/ rads show the presence of no water vapor. The same gases were also reported to result from the irradiation of crystalline glucose.more » In the solid state, the majority of the saccharides showed marked color changes following irradiation. The se colors, which were unchanged after 2 yr, varied from bright yellow with amylose, amylopectin, and glucose to dark brown with sucrose. Melibiose, lyxose, and fucose showed no change. Aqueous solutions of the irradiated materials were distinctly acid (pH 3-5). Paper chromatographic examination of the aqueous carbohydrate solutions showed no differences for the carbohydrates irradiated in air or vacuum. In marked contrast to the monosaccharides, the radiation stability of disaccharides was relatively poor. Each of the disaccharides tested yielded a large number of degradation products of which the component monosaccharides predominated. With the irradiated polysaccharides (amylose, amylopectin, and cellulose) characteristic chromatographic behavior in all solvents was a trail of reducing material often running to the end of the sheet. In the chromatography of all three compounds, only a faint spot corresponding to glucose was observed. Data are tabulated for the gas yields (H/sub 2/, CH/sub 4/, H/sub 2/O, CO, CO/sub 2/) and Rf values of the products from the irradiation of amylose, amylopectin, cellulose, trehalose, cellobiose, maltose, sucrose, lactose, and melibiose. (BBB)« less

Benzoylated ethyl 1-thioglycosides: direct preparation from per-O-benzoylated sugars

PubMed Central

Sail, Deepak; Kováč, Pavol

2012-01-01

D-Glucose, lactose, maltose, and melibiose were benzoylated with Bz2O–Et3N reagent to give fully benzoylated β products. Under the same conditions, D-mannose produced a mixture where the β-benzoate predominated. Treatment of the foregoing compounds with EtSH at slightly elevated temperature (50– 60 °C) in the presence of BF3·Et2O as a promoter gave the corresponding ethyl 1-thio glycosides in high yields. The α-products predominated in all cases in the anomeric mixtures formed. Individual products of all reactions were isolated by chromatography, they were obtained in analytically pure state, and were fully characterized by 1H and 13C NMR data and physical constants. PMID:22739243

Benzoylated ethyl 1-thioglycosides: direct preparation from per-O-benzoylated sugars.

PubMed

Sail, Deepak; Kováč, Pavol

2012-08-01

D-Glucose, lactose, maltose, and melibiose were benzoylated with Bz(2)O-Et(3)N reagent to give fully benzoylated β products. Under the same conditions, D-mannose produced a mixture where the β-benzoate predominated. Treatment of the foregoing compounds with EtSH at slightly elevated temperature (50-60°C) in the presence of BF(3)·Et(2)O as a promoter gave the corresponding ethyl 1-thio glycosides in high yields. The α-products predominated in all cases in the anomeric mixtures formed. Individual products of all reactions were isolated by chromatography, they were obtained in analytically pure state, and were fully characterized by (1)H and (13)C NMR data and physical constants. Published by Elsevier Ltd.

Isolation of Clostridium absonum and its cultural and biochemical properties.

PubMed

Hayase, M; Mitsui, N; Tamai, K; Nakamura, S; Nishida, S

1974-01-01

A new procedure for isolation of Clostridium absonum was devised. Sixtyseven strains of C. absonum were isolated from 135 soil samples, but no strain of C. absonum could be found from human fecal samples. The lecithinase, hemolysin, and lethal toxin in the culture filtrates of this species exhibited low avidity for C. perfringens type A antitoxin. The three activities were inseparable by the present method of purification. A reinvestigation of biochemical properties revealed that incomplete suppression of lecithinase reaction by C. perfringens type A antitoxin and no fermentation of raffinose, melibiose, and starch are useful criteria to differentiate C. absonum from C. perfringens, and that positive, although weak, gelatin liquefaction and fermentation of trehalose are useful to differentiate it from C. paraperfringens.

Characterization of Eubacterium coprostanoligenes sp. nov., a cholesterol-reducing anaerobe.

PubMed

Freier, T A; Beitz, D C; Li, L; Hartman, P A

1994-01-01

A small, anaerobic, gram-positive coccobacillus that reduces cholesterol to coprostanol was isolated from a hog sewage lagoon. This isolate, strain HLT (T = type strain) does not require cholesterol for growth, but it requires lecithin and has phospholipase activity. Much acid is produced by the fermentation of amygdalin, lactose, and salicin. Arabinose, cellobiose, fructose, glucose, mannose, and melibiose are fermented weakly. Acetic, formic, and succinic acids are produced, as is hydrogen. The isolate does not reduce nitrate, produce indole, or hydrolyze starch and gelatin. Esculin is hydrolyzed. The properties of strain HLT are most similar to those of members of the genus Eubacterium. Because strain HL (= ATCC 51222) has unique morphological and physiological properties, we propose that it should be the type strain of a new species in the genus Eubacterium, Eubacterium coprostanoligenes.

Developing biochemical and molecular markers for cyanobacterial inoculants.

PubMed

Prasanna, R; Madhan, K; Singh, R N; Chauhan, A K; Nain, L

2010-09-01

Markers for evaluating the establishment of cyanobacteria based on their sensitivity or resistance to antibiotics, saccharide utilization patterns and PCR generated fingerprints were developed. Four selected strains (isolates from rhizosphere soils of diverse agro-ecosystems) have shown potential as diazotrophs and exhibited plant growth promoting abilities. Different responses were obtained on screening against 40 antibiotics, which aided in developing selectable antibiotic markers for each strain. Biochemical profiles generated using standardized chromogenic identification system (including saccharide utilization tests) revealed that 53 % of the saccharides tested were not utilized by any strain, while some strains exhibited unique ability for utilization of saccharides such as melibiose, cellobiose, maltose and glucosamine. PCR based amplification profiles developed using a number of primers based on repeat sequences revealed the utility of 3 primers in providing unique fingerprints for the strains.

Survey of Some Actinomycetales for α-Galactosidase Activity1

PubMed Central

Lyons, A. J.; Pridham, T. G.; Hesseltine, C. W.

1969-01-01

The enzyme α-galactosidase offers potential to (i) eliminate possibly the flatus-inducing factor(s) in edible beans, (ii) eliminate raffinose during beet-sugar processing, and (iii) determine raffinose analytically. Accordingly, 20 genera of the order Actinomycetales Buchanan 1917 were tested for evidence of α-galactosidase activity. Test filtrates were prepared with a medium containing D-galactose and soybean meal. Enzyme activity was demonstrated through cellulose thin-layer chromatography. Of 123 strains tested, 28 produced extracellular α-galactosidase. Almost all were streptomycetes. Members of the genera Actinoplanes Couch 1950, Micromonospora ϕOrskov 1923, and Promicromonospora Krasil'nikov et al. 1961 also exhibited α-galactosidase activity. Additional tests led to the selection of five strains whose filtrates degraded melibiose, raffinose, and stachyose but not lactose and sucrose. Tests also were made with several soybean preparations. PMID:5392462

Design and application of a lactulose biosensor.

PubMed

Wu, Jieyuan; Jiang, Peixia; Chen, Wei; Xiong, Dandan; Huang, Linglan; Jia, Junying; Chen, Yuanyuan; Jin, Jian-Ming; Tang, Shuang-Yan

2017-04-07

In this study the repressor of Escherichia coli lac operon, LacI, has been engineered for altered effector specificity. A LacI saturation mutagenesis library was subjected to Fluorescence Activated Cell Sorting (FACS) dual screening. Mutant LacI-L5 was selected and it is specifically induced by lactulose but not by other disaccharides tested (lactose, epilactose, maltose, sucrose, cellobiose and melibiose). LacI-L5 has been successfully used to construct a whole-cell lactulose biosensor which was then applied in directed evolution of cellobiose 2-epimerase (C2E) for elevated lactulose production. The mutant C2E enzyme with ~32-fold enhanced expression level was selected, demonstrating the high efficiency of the lactulose biosensor. LacI-L5 can also be used as a novel regulatory tool. This work explores the potential of engineering LacI for customized molecular biosensors which can be applied in practice.

Glycosidases induced in Aspergillus tamarii. Mycelial alpha-D-galactosidases.

PubMed Central

Civas, A; Eberhard, R; Le Dizet, P; Petek, F

1984-01-01

Two alpha-D-galactosidases (alpha-D-galactoside galactohydrolase, EC 3.2.1.22) produced by Aspergillus tamarii were purified from the mycelial extract by a procedure including chromatography on hydroxyapatite, DEAE-cellulose and ECTEOLA-cellulose. Each of these enzymes showed a single protein band corresponding to the alpha-D-galactosidase activity when examined by polyacrylamide-gel electrophoresis. They catalysed the hydrolysis of o-nitrophenyl alpha-D-galactoside, melibiose, raffinose and stachyose, but did not attack the galactomannans. Their Mr values were respectively 265000 +/- 5000 and 254000 +/- 5000 by the method of Hedrick & Smith [(1968) Arch. Biochem. Biophys. 126, 155-164]. Polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate in each case showed a single protein band, with Mr 88000 and 77500 respectively. The purified enzymes contained carbohydrate, consisting of N-acetylglucosamine, mannose, glucose and galactose in the estimated molar proportions of 1:9:5:8 in alpha-galactosidase I. Images Fig. 1. PMID:6331398

MsmK, an ATPase, Contributes to Utilization of Multiple Carbohydrates and Host Colonization of Streptococcus suis.

PubMed

Tan, Mei-Fang; Gao, Ting; Liu, Wan-Quan; Zhang, Chun-Yan; Yang, Xi; Zhu, Jia-Wen; Teng, Mu-Ye; Li, Lu; Zhou, Rui

2015-01-01

Acquisition and metabolism of carbohydrates are essential for host colonization and pathogenesis of bacterial pathogens. Different bacteria can uptake different lines of carbohydrates via ABC transporters, in which ATPase subunits energize the transport though ATP hydrolysis. Some ABC transporters possess their own ATPases, while some share a common ATPase. Here we identified MsmK, an ATPase from Streptococcus suis, an emerging zoonotic bacterium causing dead infections in pigs and humans. Genetic and biochemistry studies revealed that the MsmK was responsible for the utilization of raffinose, melibiose, maltotetraose, glycogen and maltotriose. In infected mice, the msmK-deletion mutant showed significant defects of survival and colonization when compared with its parental and complementary strains. Taken together, MsmK is an ATPase that contributes to multiple carbohydrates utilization and host colonization of S. suis. This study gives new insight into our understanding of the carbohydrates utilization and its relationship to the pathogenesis of this zoonotic pathogen.

MsmK, an ATPase, Contributes to Utilization of Multiple Carbohydrates and Host Colonization of Streptococcus suis

PubMed Central

Tan, Mei-Fang; Gao, Ting; Liu, Wan-Quan; Zhang, Chun-Yan; Yang, Xi; Zhu, Jia-Wen; Teng, Mu-Ye; Li, Lu; Zhou, Rui

2015-01-01

Acquisition and metabolism of carbohydrates are essential for host colonization and pathogenesis of bacterial pathogens. Different bacteria can uptake different lines of carbohydrates via ABC transporters, in which ATPase subunits energize the transport though ATP hydrolysis. Some ABC transporters possess their own ATPases, while some share a common ATPase. Here we identified MsmK, an ATPase from Streptococcus suis, an emerging zoonotic bacterium causing dead infections in pigs and humans. Genetic and biochemistry studies revealed that the MsmK was responsible for the utilization of raffinose, melibiose, maltotetraose, glycogen and maltotriose. In infected mice, the msmK-deletion mutant showed significant defects of survival and colonization when compared with its parental and complementary strains. Taken together, MsmK is an ATPase that contributes to multiple carbohydrates utilization and host colonization of S. suis. This study gives new insight into our understanding of the carbohydrates utilization and its relationship to the pathogenesis of this zoonotic pathogen. PMID:26222651

[Comparison of efficacy of tests for differentiation of typical and atypical strains of Yersinia pestis and Yersinia pseudotuberculosis].

PubMed

Arsen'eva, T E; Lebedeva, S A; Trukhachev, A L; Vasil'eva, E A; Ivanova, V S; Bozhko, N V

2010-01-01

To characterize species specificity of officially recommended tests for differentiation of Yersiniapestis and Yersinia pseudotuberculosis and propose additional tests allowing for more accurate identification. Natural, laboratory and typical strains oftwo Yersinia species were studied using microbiological, molecular and biochemical methods. For PCR species-specific primers complementary to certain fragments of chromosomal DNA of each species as well as to several plasmid genes of Y. pestis were used. It was shown that such attributes of Y. pestis as form of colonies, fermentation ofrhamnose, melibiose and urea, susceptibility to diagnostic phages, nutritional requirements could be lost in pestis bacterial species or detected in pseudotuberculosis species. Such attribute as mobility as well as positive result of CoA-reaction on fraction V antigen are more reliable. Guaranteed differentiation of typical and changed according to differential tests strains is provided only by PCR-analysis with primers vlml2for/ISrev216 and JS respectively, which are homologous to certain chromosome fragments of one of two Yersinia species.

A Member of Complementary Medicinal Food: Anatolian Royal Jellies, Their Chemical Compositions, and Antioxidant Properties.

PubMed

Kolayli, Sevgi; Sahin, Huseyin; Can, Zehra; Yildiz, Oktay; Malkoc, Meltem; Asadov, Alsever

2016-10-01

This study investigated various chemical and antioxidant properties of Anatolian royal jelly samples. Moisture, pH, total protein, 10-hydroxy-2-decenoic acid (10-HDA) and sugars were analyzed from 18 samples. Total phenolic contents, ferric reducing antioxidant capacity and 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activity were measured as antioxidant determinants. 10-HDA contents and total protein content of fresh weight ranged between 1.0% and 3.9%, and 11.4% and 15.8%, respectively. The main sugars detected were glucose and fructose. Maltose, trehalose, and melibiose were detected at less than 1.0% in all samples. Lactose, a milk sugar, was detected in only 3 samples, at values between 0.8% and 1.4%. Total henolic content ranged from 91.0 to 301.0 mg gallic acid equivalents/kg fresh weight. Antioxidant activity is due to both to the total phenolic content, proteins and fatty acids of royal jelly. Anatolian royal jelly samples were not different from other royal jelly samples from across the world. © The Author(s) 2015.

Mechanistic Study of Utilization of Water-Insoluble Saccharomyces cerevisiae Glucans by Bifidobacterium breve Strain JCM1192

PubMed Central

Keung, Hoi Yee; Li, Tsz Kai; Sham, Lok To; Cheung, Man Kit; Cheung, Peter Chi Keung

2017-01-01

ABSTRACT Bifidobacteria exert beneficial effects on hosts and are extensively used as probiotics. However, due to the genetic inaccessibility of these bacteria, little is known about their mechanisms of carbohydrate utilization and regulation. Bifidobacterium breve strain JCM1192 can grow on water-insoluble yeast (Saccharomyces cerevisiae) cell wall glucans (YCWG), which were recently considered as potential prebiotics. According to the results of 1H nuclear magnetic resonance (NMR) spectrometry, the YCWG were composed of highly branched (1→3,1→6)-β-glucans and (1→4,1→6)-α-glucans. Although the YCWG were composed of 78.3% β-glucans and 21.7% α-glucans, only α-glucans were consumed by the B. breve strain. The ABC transporter (malEFG1) and pullulanase (aapA) genes were transcriptionally upregulated in the metabolism of insoluble yeast glucans, suggesting their potential involvement in the process. A nonsense mutation identified in the gene encoding an ABC transporter ATP-binding protein (MalK) led to growth failure of an ethyl methanesulfonate-generated mutant with yeast glucans. Coculture of the wild-type strain and the mutant showed that this protein was responsible for the import of yeast glucans or their breakdown products, rather than the export of α-glucan-catabolizing enzymes. Further characterization of the carbohydrate utilization of the mutant and three of its revertants indicated that this mutation was pleiotropic: the mutant could not grow with maltose, glycogen, dextrin, raffinose, cellobiose, melibiose, or turanose. We propose that insoluble yeast α-glucans are hydrolyzed by extracellular pullulanase into maltose and/or maltooligosaccharides, which are then transported into the cell by the ABC transport system composed of MalEFG1 and MalK. The mechanism elucidated here will facilitate the development of B. breve and water-insoluble yeast glucans as novel synbiotics. IMPORTANCE In general, Bifidobacterium strains are genetically intractable. Coupling classic forward genetics with next-generation sequencing, here we identified an ABC transporter ATP-binding protein (MalK) responsible for the import of insoluble yeast glucan breakdown products by B. breve JCM1192. We demonstrated the pleiotropic effects of the ABC transporter ATP-binding protein in maltose/maltooligosaccharide, raffinose, cellobiose, melibiose, and turanose transport. With the addition of transcriptional analysis, we propose that insoluble yeast glucans are broken down by extracellular pullulanase into maltose and/or maltooligosaccharides, which are then transported into the cell by the ABC transport system composed of MalEFG1 and MalK. The mechanism elucidated here will facilitate the development of B. breve and water-insoluble yeast glucans as novel synbiotics. PMID:28115383

Mechanistic Study of Utilization of Water-Insoluble Saccharomyces cerevisiae Glucans by Bifidobacterium breve Strain JCM1192.

PubMed

Keung, Hoi Yee; Li, Tsz Kai; Sham, Lok To; Cheung, Man Kit; Cheung, Peter Chi Keung; Kwan, Hoi Shan

2017-04-01

Bifidobacteria exert beneficial effects on hosts and are extensively used as probiotics. However, due to the genetic inaccessibility of these bacteria, little is known about their mechanisms of carbohydrate utilization and regulation. Bifidobacterium breve strain JCM1192 can grow on water-insoluble yeast ( Saccharomyces cerevisiae ) cell wall glucans (YCWG), which were recently considered as potential prebiotics. According to the results of 1 H nuclear magnetic resonance (NMR) spectrometry, the YCWG were composed of highly branched (1→3,1→6)-β-glucans and (1→4,1→6)-α-glucans. Although the YCWG were composed of 78.3% β-glucans and 21.7% α-glucans, only α-glucans were consumed by the B. breve strain. The ABC transporter ( malEFG1 ) and pullulanase ( aapA ) genes were transcriptionally upregulated in the metabolism of insoluble yeast glucans, suggesting their potential involvement in the process. A nonsense mutation identified in the gene encoding an ABC transporter ATP-binding protein (MalK) led to growth failure of an ethyl methanesulfonate-generated mutant with yeast glucans. Coculture of the wild-type strain and the mutant showed that this protein was responsible for the import of yeast glucans or their breakdown products, rather than the export of α-glucan-catabolizing enzymes. Further characterization of the carbohydrate utilization of the mutant and three of its revertants indicated that this mutation was pleiotropic: the mutant could not grow with maltose, glycogen, dextrin, raffinose, cellobiose, melibiose, or turanose. We propose that insoluble yeast α-glucans are hydrolyzed by extracellular pullulanase into maltose and/or maltooligosaccharides, which are then transported into the cell by the ABC transport system composed of MalEFG1 and MalK. The mechanism elucidated here will facilitate the development of B. breve and water-insoluble yeast glucans as novel synbiotics. IMPORTANCE In general, Bifidobacterium strains are genetically intractable. Coupling classic forward genetics with next-generation sequencing, here we identified an ABC transporter ATP-binding protein (MalK) responsible for the import of insoluble yeast glucan breakdown products by B. breve JCM1192. We demonstrated the pleiotropic effects of the ABC transporter ATP-binding protein in maltose/maltooligosaccharide, raffinose, cellobiose, melibiose, and turanose transport. With the addition of transcriptional analysis, we propose that insoluble yeast glucans are broken down by extracellular pullulanase into maltose and/or maltooligosaccharides, which are then transported into the cell by the ABC transport system composed of MalEFG1 and MalK. The mechanism elucidated here will facilitate the development of B. breve and water-insoluble yeast glucans as novel synbiotics. Copyright © 2017 American Society for Microbiology.

Vibrio rotiferianus sp. nov., isolated from cultures of the rotifer Brachionus plicatilis.

PubMed

Gomez-Gil, B; Thompson, F L; Thompson, C C; Swings, J

2003-01-01

Five Gram-negative bacterial strains, oxidase-positive, motile by means of more than one polar flagella, facultative anaerobe, arginine dihydrolase-negative, lysine- and omithine decarboxylase-positive, sensitive to the vibriostatic agent O/129, were isolated from a flow-through rotifer culture system in Gent, Belgium, and previously characterized by fluorescent amplified fragment length polymorphism. Comparison of the 16S rDNA sequence of strain LMG 21460T indicated close relationships (approximately 99% similarity) to Vibrio campbellii, Vibrio harveyi, Vibrio alginolyticus and Vibrio parahaemolyticus. However, DNA hybridization experiments revealed similarity values below 70% with its closest species V. campbellii and V. harveyi. Additionally, the analysed strains differ from related Vibrio species by the utilization of melibiose and production of acid from L-arabinose and amygdalin. Among the strains analysed, differences were observed in some phenotypic characters, particularly susceptibility to ampicillin, polymyxin B and amikacin, and urease activity. The major fatty acids identified were 16:0, 18:1 omega7c, 14:0, 12:0 3-OH and 18:0. Vibrio rotiferianus sp. nov. is proposed, with type strain LMG 21460T (=CAIM 577T); it has a DNA G+C content of 44.5 +/- 0.01 mol%.

A Fungal α-Galactosidase from Tricholoma matsutake with Broad Substrate Specificity and Good Hydrolytic Activity on Raffinose Family Oligosaccharides.

PubMed

Geng, Xueran; Tian, Guoting; Zhao, Yongchang; Zhao, Liyan; Wang, Hexiang; Ng, Tzi Bun

2015-07-24

An acidic α-galactosidase designated as TMG was purified from the fruiting bodies The purification protocol entailed ion exchange chromatography on Q-Sepharose and of Tricholoma matsutake with 136-fold purification and a specific activity of 909 units/mg. Mono-Q and fast protein liquid chromatography on Superdex 75. TMG is a monomeric protein exhibiting a molecular mass of 47 kDa in SDS-PAGE and gel filtration. The purified enzyme was identified by LC-MS/MS and three inner amino acid sequences were obtained. The optimum pH and temperature for TMG with pNPGal as substrate were pH 4.5 and 55 °C, respectively. The α-galactosidase activity was strongly inhibited by K+, Ca2+, Cd2+, Hg2+, Ag+ and Zn2+ ions. The enzyme activity was inhibited by the chemical modification agent N-bromosuccinimide (NBS), indicating the importance of tryptophan residue(s) at or near the active site. Besides hydrolyzing pNPGal, TMG also efficaciously catalyzed the degradation of natural substrates such as stachyose, raffinose, and melibiose. Thus TMG can be exploited commercially for improving the nutritional value of soy milk by degradation of indigestible oligosaccharides.

Transfer of the potato plant isolates of Pectobacterium wasabiae to Pectobacterium parmentieri sp. nov.

PubMed

Khayi, Slimane; Cigna, Jérémy; Chong, Teik Min; Quêtu-Laurent, Angélique; Chan, Kok-Gan; Hélias, Valérie; Faure, Denis

2016-12-01

Pectobacterium wasabiae was originally isolated from Japanese horseradish (Eutrema wasabi), but recently some Pectobacterium isolates collected from potato plants and tubers displaying blackleg and soft rot symptoms were also assigned to P. wasabiae. Here, combining genomic and phenotypical data, we re-evaluated their taxonomic position. PacBio and Illumina technologies were used to complete the genome sequences of P. wasabiae CFBP 3304T and RNS 08-42-1A. Multi-locus sequence analysis showed that the P. wasabiae strains RNS 08-42-1A, SCC3193, CFIA1002 and WPP163, which were collected from potato plant environment, constituted a separate clade from the original Japanese horseradish P. wasabiae. The taxonomic position of these strains was also supported by calculation of the in-silico DNA-DNA hybridization, genome average nucleotide indentity, alignment fraction and average nucleotide indentity values. In addition, they were phenotypically distinguished from P. wasabiae strains by producing acids from (+)-raffinose, α-d(+)-α-lactose, d(+)-galactose and (+)-melibiose but not from methyl α-d-glycopyranoside, (+)-maltose or malonic acid. The name Pectobacterium parmentieri sp. nov. is proposed for this taxon; the type strain is RNS 08-42-1AT (=CFBP 8475T=LMG 29774T).

Reclassification of Lactobacillus kimchii and Lactobacillus bobalius as later subjective synonyms of Lactobacillus paralimentarius.

PubMed

Pang, Huili; Kitahara, Maki; Tan, Zhongfang; Wang, Yanping; Qin, Guangyong; Ohkuma, Moriya; Cai, Yimin

2012-10-01

Characterization and identification of strain CW 1 ( = JCM 17161) isolated from corn silage were performed. Strain CW 1 was a Gram-positive, catalase-negative and homofermentative rod that produced the DL-form of lactic acid. This strain exhibited more than 99.6% 16S rRNA gene sequence similarity and greater than 82% DNA-DNA reassociation with type strains of Lactobacillus kimchii, L. bobalius and L. paralimentarius. To clarify the taxonomic positions of these type strains, phenotypic characterization, 16S rRNA gene sequencing, ribotyping and DNA-DNA relatedness were examined. The three type strains displayed different L-arabinose, lactose, melibiose, melezitose, raffinose and N-acetyl-β-glucosaminidase fermentation patterns. Phylogenetic analysis showed that L. paralimentarius is a closer neighbour of L. kimchii and L. bobalius, sharing 99.5-99.9% 16S rRNA gene sequence similarity, which was confirmed by the high DNA-DNA relatedness (≥82%) between L. paralimentarius JCM 10415(T), L. bobalius JCM 16180(T) and L. kimchii JCM 10707(T). Therefore, it is proposed that L. kimchii and L. bobalius should be reclassified as later synonyms of L. paralimentarius.

Thermus arciformis sp. nov., a thermophilic species from a geothermal area.

PubMed

Zhang, Xin-Qi; Ying, Yi; Ye, Ying; Xu, Xue-Wei; Zhu, Xu-Fen; Wu, Min

2010-04-01

Two aerobic, Gram-negative, non-motile, non-sporulating, yellow-pigmented bacteria, strains TH92(T) and TH91, were isolated from a hot spring located in Laibin, Guangxi, in the south-eastern geothermal area of China. The isolates grew at 40-77 degrees C (optimally at 70 degrees C) and at pH 6.0-9.5 (optimally at pH 7.5-8.0). Phylogenetic analysis of 16S rRNA gene sequences and levels of DNA-DNA relatedness together indicated that the new isolates represented a novel species of the genus Thermus with closest affinity to Thermus aquaticus, Thermus igniterrae and Thermus thermophilus. Compared with their closest relatives, strains TH92( T) and TH91 were able to assimilate a wider range of carbohydrates, amino acids and organic acids as sole carbon sources for growth, such as lactose and melibiose. The new isolates had lower combined levels of C(16 : 0 ) and iso-C(16 : 0) compared with their closest relatives. On the basis of polyphasic taxonomic characterization, strains TH92(T) and TH91 are considered to represent a single novel species of the genus Thermus, for which the name Thermus arciformis sp. nov. is proposed. The type strain is TH92(T) (=CGMCC 1.6992(T) =JCM 15153(T)).

Melanin production by Rhizobium meliloti GR4 is linked to nonsymbiotic plasmid pRmeGR4b: cloning, sequencing, and expression of the tyrosinase gene mepA.

PubMed Central

Mercado-Blanco, J; García, F; Fernández-López, M; Olivares, J

1993-01-01

Melanin production by Rhizobium meliloti GR4 is linked to nonsymbiotic plasmid pRmeGR4b (140 MDa). Transfer of this plasmid to GR4-cured derivatives or to Agrobacterium tumefaciens enables these bacteria to produce melanin. Sequence analysis of a 3.5-kb PstI fragment of plasmid pRmeGR4b has revealed the presence of a open reading frame 1,481-bp that codes for a protein whose sequence shows strong homology to two conserved regions involved in copper binding in tyrosinases and hemocyanins. In vitro-coupled transcription-translation experiments showed that this open reading frame codes for a 55-kDa polypeptide. Melanin production in GR4 is not under the control of the RpoN-NifA regulatory system, unlike that in R. leguminosarum bv. phaseoli 8002. The GR4 tyrosinase gene could be expressed in Escherichia coli under the control of the lacZ promoter. For avoiding confusion with mel genes (for melibiose), a change of the name of the previously reported mel genes of R. leguminosarum bv. phaseoli and other organisms to mep genes (for melanin production) is proposed. Images PMID:8366027

Population structure of the Yersinia pseudotuberculosis complex according to multilocus sequence typing

PubMed Central

Laukkanen-Ninios, Riikka; Didelot, Xavier; Jolley, Keith A.; Morelli, Giovanna; Sangal, Vartul; Kristo, Paula; Imori, Priscilla F. M.; Fukushima, Hiroshi; Siitonen, Anja; Tseneva, Galina; Voskressenskaya, Ekaterina; Falcao, Juliana P.; Korkeala, Hannu; Maiden, Martin C. J.; Mazzoni, Camila; Carniel, Elisabeth; Skurnik, Mikael; Achtman, Mark

2014-01-01

Summary Multilocus sequence analysis of 417 strains of Yersinia pseudotuberculosis revealed that it is a complex of four populations, three of which have been previously assigned species status [Y. pseudotuberculosis sensu stricto (s.s.), Yersinia pestis and Yersinia similis] and a fourth population, which we refer to as the Korean group, which may be in the process of speciation. We detected clear signs of recombination within Y. pseudotuberculosis s.s. as well as imports from Y. similis and the Korean group. The sources of genetic diversification within Y. pseudotuberculosis s.s. were approximately equally divided between recombination and mutation, whereas recombination has not yet been demonstrated in Y. pestis, which is also much more genetically monomorphic than is Y. pseudotuberculosis s.s. Most Y. pseudotuberculosis s.s. belong to a diffuse group of sequence types lacking clear population structure, although this species contains a melibiose-negative clade that is present globally in domesticated animals. Yersinia similis corresponds to the previously identified Y. pseudotuberculosis genetic type G4, which is probably not pathogenic because it lacks the virulence factors that are typical for Y. pseudotuberculosis s.s. In contrast, Y. pseudotuberculosis s.s., the Korean group and Y. pestis can all cause disease in humans. PMID:21951486

Purification and biochemical characterization of a D-galactose binding lectin from Japanese sea hare (Aplysia kurodai) eggs.

PubMed

Kawsar, S M A; Matsumoto, R; Fujii, Y; Yasumitsu, H; Dogasaki, C; Hosono, M; Nitta, K; Hamako, J; Matsui, T; Kojima, N; Ozeki, Y

2009-07-01

A lectin was purified from Japanese sea hare Aplysia kurodai by lactosyl-agarose affinity chromatography. The molecular mass of the lectin was determined to be 56 and 32 kDa by SDS-PAGE under non-reducing and reducing conditions, respectively. It was found to agglutinate trypsinized and glutaraldehyde-fixed rabbit and human erythrocytes in the absence of divalent cations. The lectin exhibited stable thermo-tolerance as it retained hemagglutinating activity for 1 h even at 80 degrees C and showed stability at pH 10. By contrast, it was very sensitive at pH less than 5 and in the presence of the sulfhydryl-group preserving reagent, beta-mercaptoethanol. The hemagglutinating activity by the lectin was specifically inhibited by D-galactose, galacturonic acid, methyl-alpha- and methyl-beta-D-galactopyranoside, lactose, melibiose, and asialofetuin. The association rate constant (k(ass)) and dissociation rate constant (k(diss)) were determined for the lectin to be 4.3 x 10(5) M(-1) x sec(-1) and 2.2 x 10(-3) sec(-1), respectively, using a surface plasmon resonance biosensor. The lectin moderately inhibited cell proliferation in the P388 cell line dose dependently. Interestingly, lectin-treated cells did not show a fragmented DNA ladder as is caused by apoptosis, suggesting that the cell proliferation inhibition was caused by another unknown mechanism.

Lactobacillus arizonensis sp. nov., isolated from jojoba meal.

PubMed

Swezey, J L; Nakamura, L K; Abbott, T P; Peterson, R E

2000-09-01

Five strains of simmondsin-degrading, lactic-acid-producing bacteria were isolated from fermented jojoba meal. These isolates were facultatively anaerobic, gram-positive, non-motile, non-spore-forming, homofermentative, rod-shaped organisms. They grew singly and in short chains, produced lactic acid but no gas from glucose, and did not exhibit catalase activity. Growth occurred at 15 and 45 degrees C. All strains fermented cellobiose, D-fructose, D-galactose, D-glucose, lactose, maltose, D-mannitol, D-mannose, melibiose, D-ribose, salicin, D-sorbitol, sucrose and trehalose. Some strains fermented L-(-)-arabinose and L-rhamnose. D-Xylose was not fermented and starch was not hydrolysed. The mean G+C content of the DNA was 48 mol%. Phylogenetic analyses of 16S rDNA established that the isolates were members of the genus Lactobacillus. DNA reassociation of 45% or less was obtained between the new isolates and the reference strains of species with G+C contents of about 48 mol%. The isolates were differentiated from other homofermentative Lactobacillus spp. on the basis of 16S rDNA sequence divergence, DNA relatedness, stereoisomerism of the lactic acid produced, growth temperature and carbohydrate fermentation. The data support the conclusion that these organisms represent strains of a new species, for which the name Lactobacillus arizonensis is proposed. The type strain of L. arizonensis is NRRL B-14768T (= DSM 13273T).

The specificity of induction of alpha-galactosidase from Saccharomyces carlsbergensis.

PubMed

Flórez, I G; Lazo, P S; Ochoa, A G; Gascón, S

1981-04-17

A number of sugars and derivatives have been tested for their ability to induce the synthesis of alpha-galactosidase from Saccharomyces carlsbergensis. Besides galactose and the substrates of the enzyme melibiose, raffinose and stachyose, D-galacturonic acid, L-arabinose, D-tagatose, methyl-alpha-D-galactoside, lactose and isopropyl-beta-D-thiogalactoside were able to act as inducers. Of these, methyl-alpha-D-galactoside, lactose, isopropyl-beta-D-thiogalactoside and L-arabinose have been shown to be gratuitous inducers with which kinetic studies of induction have been carried out. Lactose was the most efficient inducer, giving a maximal differential rate of synthesis of the enzyme of 110 mU/10(7) cells at a concentration of 180 mM, followed by L-arabinose (60 mU/10(7) cells at 40 mM), isopropyl-beta-D-thiogalactoside (43 mU/10(7) cells at 60 mM) and methyl-alpha-D-galactoside (25 mU/10(7) cells at 150 mM). The concentration of inducer required to obtain half-maximal induction was similar for lactose, L-arabinose and isopropyl-beta-D-thiogalactoside and about 5-fold higher for methyl-alpha-D-galactoside. The property of the compounds to act as inducers was compared to their ability to interact with the enzyme and the results discussed in terms of the molecular structures which are recognized by the enzyme and by the induction machinery.

Use of yeast spores for microencapsulation of enzymes.

PubMed

Shi, Libing; Li, Zijie; Tachikawa, Hiroyuki; Gao, Xiao-Dong; Nakanishi, Hideki

2014-08-01

Here, we report a novel method to produce microencapsulated enzymes using Saccharomyces cerevisiae spores. In sporulating cells, soluble secreted proteins are transported to the spore wall. Previous work has shown that the spore wall is capable of retaining soluble proteins because its outer layers work as a diffusion barrier. Accordingly, a red fluorescent protein (RFP) fusion of the α-galactosidase, Mel1, expressed in spores was observed in the spore wall even after spores were subjected to a high-salt wash in the presence of detergent. In vegetative cells, however, the cell wall cannot retain the RFP fusion. Although the spore wall prevents diffusion of proteins, it is likely that smaller molecules, such as sugars, pass through it. In fact, spores can contain much higher α-galactosidase activity to digest melibiose than vegetative cells. When present in the spore wall, the enzyme acquires resistance to environmental stresses including enzymatic digestion and high temperatures. The outer layers of the spore wall are required to retain enzymes but also decrease accessibility of the substrates. However, mutants with mild spore wall defects can retain and stabilize the enzyme while still permitting access to the substrate. In addition to Mel1, we also show that spores can retain the invertase. Interestingly the encapsulated invertase has significantly lower activity toward raffinose than toward sucrose.This suggests that substrate selectivity could be altered by the encapsulation.

NMR Quantification of Carbohydrates in Complex Mixtures. A Challenge on Honey.

PubMed

Schievano, Elisabetta; Tonoli, Marco; Rastrelli, Federico

2017-12-19

The knowledge of carbohydrate composition is greatly important to determine the properties of natural matrices such as foodstuff and food ingredients. However, because of the structural similarity and the multiple isomeric forms of carbohydrates in solution, their analysis is often a complex task. Here we propose an NMR analytical procedure based on highly selective chemical shift filters followed by TOCSY, which allows us to acquire specific background-free signals for each sugar. The method was tested on raw honey samples dissolved in water with no other pretreatment. In total, 22 sugars typically found in honey were quantified: 4 monosaccharides (glucose, fructose, mannose, rhamnose), 11 disaccharides (sucrose, trehalose, turanose, maltose, maltulose, palatinose, melibiose and melezitose, isomaltose, gentiobiose nigerose, and kojibiose), and 7 trisaccharides (raffinose, isomaltotriose, erlose, melezitose, maltotriose, panose, and 1-kestose). Satisfactory results in terms of limit of quantification (0.03-0.4 g/100g honey), precision (% RSD: 0.99-4.03), trueness (bias % 0.4-4.2), and recovery (97-104%) were obtained. An accurate control of the instrumental temperature and of the sample pH endows an optimal chemical shift reproducibility, making the procedure amenable to automation and suitable to routine analysis. While validated on honey, which is one of the most complex natural matrices in terms of saccharides composition, this innovative approach can be easily transferred to other natural matrices.

Characterization of the plant growth promoting bacterium, Enterobacter cloacae MSR1, isolated from roots of non-nodulating Medicago sativa

PubMed Central

Khalifa, Ashraf Y.Z.; Alsyeeh, Abdel-Moneium; Almalki, Mohammed A.; Saleh, Farag A.

2015-01-01

The aim of the present study was to characterize the endophytic bacterial strain designated MSR1 that was isolated from inside the non-nodulating roots of Medicago sativa after surface-sterilization. MSR1 was identified as Enterobacter cloacae using both 16S rDNA gene sequence analysis and API20E biochemical identification system (Biomerieux, France). Furthermore, this bacterium was characterized using API50CH kit (Biomerieux, France) and tested for antibacterial activities against some food borne pathogens. The results showed that E. cloacae consumed certain carbohydrates such as glycerol, d-xylose, d-maltose and esculin melibiose as a sole carbon source and certain amino acids such as arginine, tryptophan ornithine as nitrogen source. Furthermore, MSR1 possessed multiple plant-growth promoting characteristics; phosphate solubility, production of phytohormones acetoin and bioactive compounds. Inoculation of Pisum sativum with MSR1 significantly improved the growth parameters (the length and dry weight) of this economically important grain legume compared to the non-treated plants. To our knowledge, this is the first report addressing E. cloacae which exist in roots of alfalfa growing in Al-Ahsaa region. The results confirmed that E. cloacae exhibited traits for plant growth promoting and could be developed as an eco-friendly biofertilizer for P. sativum and probably for other important plant species in future. PMID:26858542

Lectin from embryos and oocytes of Xenopus laevis. Purification and properties.

PubMed

Roberson, M M; Barondes, S H

1982-07-10

Soluble extracts of Xenopus laevis blastula stage embryos, oocytes, and adult liver contain lectin activities detected by agglutination of trypsinized, glutaraldehyde-fixed rabbit erythrocytes. Lectin from the embryos and oocytes was purified by affinity chromatography on a column derivatized with melibiose. Trace contaminants were removed either by preparative isoelectric focusing or by gel filtration. Based on its behavior on Sepharose 6B the purified oocyte lectin has an apparent molecular weight of approximately 480,000. On sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions there were two major bands with molecular weight ranges of about 43,000 and 45,000, with diffuse trails. Since the purified lectin contains about 20% saccharides by weight and since both bands are glycosylated, diffuseness might be due to variable glycosylation. Heterogeneity was indicated by isoelectric focusing in polyacrylamide gels, which showed four protein bands with isoelectric points ranging from 4.4 to 4.9. Lectins from both embryos and oocytes comprised about 1 to 2% of the total soluble protein and could not be distinguished by sodium dodecyl sulfate polyacrylamide gel electrophoresis. However, the specific hemagglutination activity of the purified oocyte lectin was, on the average, 7-fold higher. Levels in crude extracts of liver were 3 orders of magnitude lower than those from oocytes. The hemagglutination activities of the lectins from embryos, oocytes, and adult liver required Ca2+ and were blocked by similar concentrations of both alpha- and beta-galactosides.

Carbon Source Requirements for Exopolysaccharide Production by Lactobacillus casei CG11 and Partial Structure Analysis of the Polymer

PubMed Central

Cerning, J.; Renard, C. M. G. C.; Thibault, J. F.; Bouillanne, C.; Landon, M.; Desmazeaud, M.; Topisirovic, L.

1994-01-01

Exopolysaccharide production by Lactobacillus casei CG11 was studied in basal minimum medium containing various carbon sources (galactose, glucose, lactose, sucrose, maltose, melibiose) at concentrations of 2, 5, 10, and 20 g/liter. L. casei CG11 produced exopolysaccharides in basal minimum medium containing each of the sugars tested; lactose and galactose were the poorest carbon sources, and glucose was by far the most efficient carbon source. Sugar concentrations had a marked effect on polymer yield. Plasmid-cured Muc- derivatives grew better in the presence of glucose and attained slightly higher populations than the wild-type strain. The values obtained with lactose were considerably lower for both growth and exopolysaccharide yield. The level of specific polymer production per cell obtained with glucose was distinctively lower for Muc- derivatives than for the Muc+ strain. The polymer produced by L. casei CG11 in the presence of glucose was different from that formed in the presence of lactose. The polysaccharide produced by L. casei CG11 in basal minimum medium containing 20 g of glucose per liter had an intrinsic viscosity of 1.13 dl/g. It was rich in glucose (76%), which was present mostly as 2- or 3-linked residues along with some 2,3 doubly substituted glucose units, and in rhamnose (21%), which was present as 2-linked or terminal rhamnose; traces of mannose and galactose were also present. PMID:16349427

Photobacterium jeanii sp. nov., isolated from corals and zoanthids.

PubMed

Chimetto, Luciane A; Cleenwerck, Ilse; Thompson, Cristiane C; Brocchi, Marcelo; Willems, Anne; De Vos, Paul; Thompson, Fabiano L

2010-12-01

Four novel isolates (R-40508(T), R-40507, R-40903 and R-21419) were obtained from different cnidarian species (Phyllogorgia dilatata, Merulina ampliata and Palythoa caribaeorum) from different places in Brazil and Australia. The novel isolates formed a tight phylogenetic group based on 16S rRNA, recA, topA, ftsZ, mreB and rpoA gene sequences. Their closest phylogenetic neighbours were the type strains of Photobacterium leiognathi, P. rosenbergii and P. halotolerans, sharing 97.1-97.5 % 16S rRNA gene sequence similarity. DNA-DNA hybridization between a representative strain (R-40508(T)) and the type strains of these Photobacterium species revealed less than 20 % relatedness, showing that the new isolates belong to a novel species. Several phenotypic features allow the differentiation of the novel species from its closest phylogenetic neighbours. It has gelatinase and lipase activity and can utilize melibiose, but it cannot grow on 6 % NaCl. In addition, the novel species has the fatty acid iso-C(16 : 0), but lacks the fatty acids C(17 : 0), C(17 : 0) cyclo, iso-C(17 : 0), C(17 : 1)ω8c and iso-C(17 : 1)ω9c. The name Photobacterium jeanii sp. nov. is proposed for this species, with the type strain R-40508(T) (=LMG 25436(T) =CAIM 1817(T)). The G+C content of the type strain is 45.5mol%.

Erwinia gerundensis sp. nov., a cosmopolitan epiphyte originally isolated from pome fruit trees.

PubMed

Rezzonico, Fabio; Smits, Theo H M; Born, Yannick; Blom, Jochen; Frey, Jürg E; Goesmann, Alexander; Cleenwerck, Ilse; de Vos, Paul; Bonaterra, Anna; Duffy, Brion; Montesinos, Emilio

2016-03-01

A survey to obtain potential antagonists of pome fruit tree diseases yielded two yellow epiphytic bacterial isolates morphologically similar to Pantoea agglomerans , but showing no biocontrol activity. Whole-cell MALDI-TOF mass spectrometry and analysis of 16S rRNA gene and gyrB sequences suggested the possibility of a novel species with a phylogenetic position in either the genus Pantoea or the genus Erwinia . Multi-locus sequence analysis (MLSA) placed the two strains in the genus Erwinia and supported their classification as a novel species. The strains showed general phenotypic characteristics typical of this genus and results of DNA-DNA hybridizations confirmed that they represent a single novel species. Both strains showed a DNA G+C content, as determined by HPLC, of 54.5 mol% and could be discriminated from phylogenetically related species of the genus Erwinia by their ability to utilize potassium gluconate, potassium 2-ketogluconate, maltose, melibiose and raffinose. Whole-genome sequencing of strain EM595 T revealed the presence of a chromosomal carotenoid biosynthesis gene cluster similar to those found in species of the genera Cronobacter and Pantoea that explains the pigmentation of the strain, which is atypical for the genus Erwinia . Additional strains belonging to the same species were recovered from different plant hosts in three different continents, revealing the cosmopolitan nature of this epiphyte. The name Erwinia gerundensis sp. nov. is proposed, with EM595 T ( = LMG 28990 T  = CCOS 903 T ) as the designated type strain.

Lachancea quebecensis sp. nov., a yeast species consistently isolated from tree bark in the Canadian province of Québec.

PubMed

Freel, Kelle C; Charron, Guillaume; Leducq, Jean-Baptiste; Landry, Christian R; Schacherer, Joseph

2015-10-01

A thorough sampling of maple, oak, birch, and apple tree bark in North America yielded a set of isolates that represent a yeast species not yet formally described. The strains obtained were all isolated from the Canadian province of Québec. These four isolates have identical electrophoretic karyotypes, distinct from other species of the genus Lachancea, and are most closely related to the formally recognized species Lachancea thermotolerans according to the D1/D2 domain of the LSU rDNA gene and 5.8S–ITS region. Previous studies revealed the existence of a population of strains closely related to L. thermotolerans, with unique D1/D2 sequences and the ability to grow on melibiose, which is also true for these isolates. The sequences obtained here (for the D1/D2, and 5.8S–ITS region) are identical among the four strains, and in a phylogenetic analysis of the D1/D2 region, the strains form a distinct clade with the previously described population closely related to L. thermotolerans, composed of isolates from Japan, as well as from the provinces of Ontario and Québec in Canada. On the basis of select physiological and phylogenetic characteristics, a novel ascosporogenous yeast species, Lachancea quebecensis sp. nov., is proposed. The type strain LL11_022T ( = CBS 14138T = CLIB 1763T = UCDFST 15-106T) was isolated from maple tree bark in the Station Duchesnay, QC region of Québec, Canada. The MycoBank number is MB811749.

Lactobacillus herbarum sp. nov., a species related to Lactobacillus plantarum.

PubMed

Mao, Yuejian; Chen, Meng; Horvath, Philippe

2015-12-01

Strain TCF032-E4 was isolated from a traditional Chinese fermented radish. It shares >99% 16S rRNA sequence identity with L. plantarum, L. pentosus and L. paraplantarum. This strain can ferment ribose, galactose, glucose, fructose, mannose, mannitol, N-acetylglucosamine, amygdalin, arbutin, salicin, cellobiose, maltose, lactose, melibiose, trehalose and gentiobiose. It cannot ferment sucrose, which can be used by L. pentosus, L. paraplantarum, L. fabifermentans, L. xiangfangensis and L. mudanjiangensis, as well as most of the L. plantarum strains (88.7%). TCF032-E4 cannot grow at temperature above 32 °C. This strain shares 78.2-83.6% pheS (phenylalanyl-tRNA synthetase alpha subunit) and 89.5-94.9% rpoA (RNA polymerase alpha subunit) sequence identity with L. plantarum, L. pentosus, L. paraplantarum, L. fabifermentans, L. xiangfangensis and L. mudanjiangensis. These results indicate that TCF032-E4 represents a distinct species. This hypothesis was further confirmed by whole-genome sequencing and comparison with available genomes of related species. The draft genome size of TCF032-E4 is approximately 2.9 Mb, with a DNA G+C content of 43.5 mol%. The average nucleotide identity (ANI) between TCF032-E4 and related species ranges from 79.0 to 81.1%, the highest ANI value being observed with L. plantarum subsp. plantarum ATCC 14917T. A novel species, Lactobacillus herbarum sp. nov., is proposed with TCF032-E4T ( = CCTCC AB2015090T = DSM 100358T) as the type strain.

Lectin activity in mycelial extracts of Fusarium species.

PubMed

Bhari, Ranjeeta; Kaur, Bhawanpreet; Singh, Ram S

2016-01-01

Lectins are non-immunogenic carbohydrate-recognizing proteins that bind to glycoproteins, glycolipids, or polysaccharides with high affinity and exhibit remarkable ability to agglutinate erythrocytes and other cells. In the present study, ten Fusarium species previously not explored for lectins were screened for the presence of lectin activity. Mycelial extracts of F. fujikuroi, F. beomiformii, F. begoniae, F. nisikadoi, F. anthophilum, F. incarnatum, and F. tabacinum manifested agglutination of rabbit erythrocytes. Neuraminidase treatment of rabbit erythrocytes increased lectin titers of F. nisikadoi and F. tabacinum extracts, whereas the protease treatment resulted in a significant decline in agglutination by most of the lectins. Results of hapten inhibition studies demonstrated unique carbohydrate specificity of Fusarium lectins toward O-acetyl sialic acids. Activity of the majority of Fusarium lectins exhibited binding affinity to d-ribose, l-fucose, d-glucose, l-arabinose, d-mannitol, d-galactosamine hydrochloride, d-galacturonic acid, N-acetyl-d-galactosamine, N-acetyl-neuraminic acid, 2-deoxy-d-ribose, fetuin, asialofetuin, and bovine submaxillary mucin. Melibiose and N-glycolyl neuraminic acid did not inhibit the activity of any of the Fusarium lectins. Mycelial extracts of F. begoniae, F. nisikadoi, F. anthophilum, and F. incarnatum interacted with most of the carbohydrates tested. F. fujikuroi and F. anthophilum extracts displayed strong interaction with starch. The expression of lectin activity as a function of culture age was investigated. Most species displayed lectin activity on the 7th day of cultivation, and it varied with progressing of culture age. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Serratia glossinae sp. nov., isolated from the midgut of the tsetse fly Glossina palpalis gambiensis.

PubMed

Geiger, A; Fardeau, M-L; Falsen, E; Ollivier, B; Cuny, G

2010-06-01

We report the isolation of a novel bacterium, strain C1(T), from the midgut of the tsetse fly Glossina palpalis gambiensis, one of the vector insects responsible for transmission of the trypanosomes that cause sleeping sickness in sub-Saharan African countries. Strain C1(T) is a motile, facultatively anaerobic, rod-like bacterium (0.8-1.0 microm in diameter; 2-6 microm long) that grows as single cells or in chains. Optimum growth occurred at 25-35 degrees C, at pH 6.7-8.4 and in medium containing 5-20 g NaCl l(-1). The bacterium hydrolysed urea and used L-lysine, L-ornithine, citrate, pyruvate, D-glucose, D-mannitol, inositol, D-sorbitol, melibiose, amygdalin, L-arabinose, arbutin, aesculin, D-fructose, D-galactose, glycerol, maltose, D-mannose, raffinose, trehalose and d-xylose; it produced acetoin, reduced nitrate to nitrite and was positive for beta-galactosidase and catalase. The DNA G+C content was 53.6 mol%. It was related phylogenetically to members of the genus Serratia, family Enterobacteriaceae, the type strain of Serratia fonticola being its closest relative (99 % similarity between 16S rRNA gene sequences). However, DNA-DNA relatedness between strain C1(T) and S. fonticola DSM 4576(T) was only 37.15 %. Therefore, on the basis of morphological, nutritional, physiological and fatty acid analysis and genetic criteria, strain C1(T) is proposed to be assigned to a novel Serratia species, Serratia glossinae sp. nov. (type strain C1(T) =DSM 22080(T) =CCUG 57457(T)).

Adult Parasitoids of Honeydew-Producing Insects Prefer Honeydew Sugars to Cover their Energetic Needs.

PubMed

Lenaerts, Marijke; Abid, Lamis; Paulussen, Caroline; Goelen, Tim; Wäckers, Felix; Jacquemyn, Hans; Lievens, Bart

2016-10-01

To meet their carbohydrate requirements, adult parasitoids exploit a broad range of sugar resources, including floral and extrafloral nectar and honeydew. Although honeydew might be the predominant sugar source, especially in agricultural systems, it often is nutritionally inferior to sugar sources like nectar. Given its broad availability, it may be expected that sugar-feeding insects have evolved specialized adaptations to deal with this typically inferior sugar source. This would apply especially to organisms that have a close association with honeydew producers. Here, we hypothesized that parasitoids of honeydew-producing insects should show a pronounced response to sugars, such as fructose, sucrose, melezitose, and trehalose, and to a lesser extent glucose. To test this hypothesis, we investigated sugar consumption, feeding behavior and survival of the aphid parasitoid Aphidius ervi on several sugars (equiweight solutions). Our results show that A. ervi adults consumed typical honeydew sugars (sucrose, fructose, trehalose, and melezitose) the most, while consuming considerably less glucose or melibiose. Rhamnose, which does not occur in aphid honeydew, was not, or was only marginally, consumed. When different sugars were provided at the same time, A. ervi adults preferred sucrose or fructose over glucose or melezitose. Furthermore, pre-exposure to sucrose or fructose significantly reduced subsequent intake of glucose, suggesting an acquired distaste for glucose after being previously exposed to highly preferred sugars such as sucrose and fructose. Altogether, this study shows that A. ervi adults prefer sugars (fructose, melezitose, trehalose, and sucrose) that are overrepresented in aphid honeydew and show a lower preference to one (glucose) that is underrepresented in honeydew.

Characterization of Atypical Isolates of Yersinia intermedia and Definition of Two New Biotypes▿ †

PubMed Central

Martin, Liliane; Leclercq, Alexandre; Savin, Cyril; Carniel, Elisabeth

2009-01-01

The species Yersinia intermedia is a member of the genus Yersinia which belongs to the Enterobacteriaceae family. This species is divided into eight biotypes, according to Brenner's biotyping scheme. This scheme relies on five tests (utilization of Simmons citrate and acid production from d-melibiose, d-raffinose, α-methyl-d-glucoside [αMG], and l-rhamnose). The collection of the French Yersinia Reference Laboratory (Institut Pasteur, Paris, France) contained 44 strains that were originally identified as Y. intermedia but whose characteristics did not fit into the biotyping scheme. These 44 strains were separated into two biochemical groups: variant 1 (positive for acid production from l-rhamnose and αMG and positive for Simmons citrate utlization) and variant 2 (positive for acid production from l-rhamnose and αMG). These atypical strains could correspond to new biotypes of Y. intermedia, to Y. frederiksenii strains having the atypical property of fermenting αMG, or to new Yersinia species. These strains did not exhibit growth or phenotypic properties different from those of Y. intermedia and Y. frederiksenii and did not harbor any of the virulence traits usually found in pathogenic species. DNA-DNA hybridizations performed between one strain each of variants 1 and 2 and the Y. intermedia and Y. frederiksenii type strains demonstrated that these variants do belong to the Y. intermedia species. We thus propose that Brenner's biotyping scheme be updated by adding two new biotypes: 9 (for variant 1) and 10 (for variant 2) to the species Y. intermedia. PMID:19494062

Differential metabolic responses of perennial grass Cynodon transvaalensis×Cynodon dactylon (C₄) and Poa Pratensis (C₃) to heat stress.

PubMed

Du, Hongmei; Wang, Zhaolong; Yu, Wenjuan; Liu, Yimin; Huang, Bingru

2011-03-01

Differential metabolic responses to heat stress may be associated with variations in heat tolerance between cool-season (C₃) and warm-season (C₄) perennial grass species. The main objective of this study was to identify metabolites associated with differential heat tolerance between C₄ bermudagrass and C₃ Kentucky bluegrass by performing metabolite profile analysis using gas chromatography-mass spectrometry. Plants of Kentucky bluegrass (Poa Pratensis'Midnight') and hybrid bermudagrass (Cynodon transvaalensis x Cynodon dactylon'Tifdwarf') were grown under optimum temperature conditions (20/15 °C for Kentucky bluegrass and 30/25 °C for bermudagrass) or heat stress (35/30 °C for Kentucky bluegrass and 45/40 °C for bermudagrass). Physiological responses to heat stress were evaluated by visual rating of grass quality, measuring photochemical efficiency (variable fluorescence to maximal fluorescence) and electrolyte leakage. All of these parameters indicated that bermudagrass exhibited better heat tolerance than Kentucky bluegrass. The metabolite analysis of leaf polar extracts revealed 36 heat-responsive metabolites identified in both grass species, mainly consisting of organic acids, amino acids, sugars and sugar alcohols. Most metabolites showed higher accumulation in bermudagrass compared with Kentucky bluegrass, especially following long-term (18 days) heat stress. The differentially accumulated metabolites included seven sugars (sucrose, fructose, galactose, floridoside, melibiose, maltose and xylose), a sugar alcohol (inositol), six organic acids (malic acid, citric acid, threonic acid, galacturonic acid, isocitric acid and methyl malonic acid) and nine amino acids (Asn, Ala, Val, Thr, γ-aminobutyric acid, IIe, Gly, Lys and Met). The differential accumulation of those metabolites could be associated with the differential heat tolerance between C₃ Kentucky bluegrass and C₄ bermudagrass. Copyright © Physiologia Plantarum 2010.

Effect of different monosaccharides and disaccharides on boar sperm quality after cryopreservation.

PubMed

Gómez-Fernández, José; Gómez-Izquierdo, Emilio; Tomás, Cristina; Mocé, Eva; de Mercado, Eduardo

2012-07-01

The aim of the present study was to evaluate the cryoprotectant effect of different non-permeating sugars for boar sperm. Pooled semen from three boars was used for the experiments. In the first experiment, the sperm quality of boar sperm cryopreserved with an egg-yolk based extender supplemented with different monosaccharides (glucose, galactose or fructose) was compared to a control cryopreserved in lactose-egg yolk extender. In the second experiment, the effect of five disaccharides (lactose, sucrose, lactulose, trehalose or melibiose) on boar sperm cryosurvival was studied. Several sperm quality parameters were assessed by flow cytometry in samples incubated for 30 and 150 min at 37°C after thawing: percentages of sperm with intact plasma membrane (SIPM), sperm presenting high plasma membrane fluidity (HPMF), sperm with intracellular reactive oxygen substances production (IROSP) and apoptotic sperm (AS). In addition, the percentages of total motile (TMS) and progressively motile sperm (PMS) were assessed at the same incubation times with a computer-assisted sperm analysis system. Freezing extenders supplemented with each of the monosaccharide presented smaller cryoprotective effect than the control extender supplemented with lactose (P<0.05). However, from the three monosaccharides tested, glucose provided the best sperm quality after freezing-thawing. With respect to the disaccharides studied, samples frozen with the extender supplemented with lactulose exhibited in general the lowest sperm quality, except for the percentage of capacitated sperm, which was highest (P<0.05) in the samples cryopreserved with the trehalose extender. Our results suggest that disaccharides have higher cryoprotective effect than monosaccharides, although the monosaccharide composition of the disaccharides is also important, since the best results were obtained with those disaccharides presenting glucose in their composition. Copyright © 2012 Elsevier B.V. All rights reserved.

Comparative study of invertases of Streptococcus mutans.

PubMed

Tanzer, J M; Brown, A T; McInerney, M F; Woodiel, F N

1977-04-01

Sucrase activity was studied in 13 strains of Streptococcus mutans representing the five Bratthall serotypes. Sucrose-adapted cells have sucrase activity in the 37,000 x g-soluble fraction of all strains. The enzyme was identified as invertase (beta-d-fructofuranoside fructohydrolase; EC 3.2.1.26) because it hydrolyzed the beta-fructofuranoside trisaccharide raffinose, giving fructose and melibiose as its products, and because it hydrolyzed the beta-fructofuranoside dissacharide sucrose, giving equimolar glucose and fructose as its products. Invertases of c and e strains exhibit two activity peaks by molecular exclusion chromatography with molecular weights of 45,000 to 50,000 and about 180,000; those of serotypes a, b, and d strains exhibit only a single component of 45,000 to 50,000 molecular weight. The electrophoretic mobility of invertases is different between the serotypes and the same within them. Inorganic orthophosphate (P(i)) has a weak positive effect on the V(max) of invertases of serotypes c and e cells but a strong positive effect on the invertases of serotype b cells; P(i) has a strong positive effect on the apparent K(m) of the invertases of serotype d cells, but has no effect on the V(max); P(i) has a strong positive effect on both the apparent K(m) and V(max) of the invertases of serotype a cells. Thus, the invertases were different between all of the serotypes but similar within the serotypes. These findings support the taxonomic schemes of Coykendall and of Bratthall. It was additionally noted that 37,000 x g-soluble fractions of only serotypes b and c but not serotypes a, d, and e cells have melibiase activity, and it could be deduced that serotype d cells lack an intact raffinose permease system.

Reduction of soybean oligosaccharides and properties of alpha-D-galactosidase from Lactobacillus curvatus R08 and Leuconostoc mesenteroides [corrected] JK55.

PubMed

Yoon, Mi Young; Hwang, Han-Joon

2008-09-01

This study was undertaken to investigate the potential for reducing non-digestive oligosaccharides (NDO) in soy foods, as well as the influence of exogenous conditions on intracellular alpha-galactosidase (alpha-Gal) producing lactic acid bacteria. Two strains, Lactobacillus curvatus R08 and Leuconostoc mesenteroides [corrected]JK55, showed the highest levels of raffinose degrading activity at over 40 U mL(-1), and presented maximum activities during the stationary phase in a medium where raffinose was the only carbon source. Raffinose was the most effective inducer, followed by melibiose, and galactose; the enzymes were partially inhibited by fructose and sucrose. On the other hand, limited activity was observed in glucose. The strains displayed optimum activity levels at neutral pH and a 35-37 degrees C temperature range. The alpha-Gal activities of L. curvatus R08 and Leu. mesenteroides [corrected] JK55 were maintained at pH 6.5-10.0. The activity of the alpha-Gal enzyme was stable in a relatively broad range of temperatures from 0 to 40 degrees C for 3h. In soymilk, Leu. mesenteroides [corrected] JK55 and L. curvatus R08 completely hydrolyzed the NDO after 18-24h of fermentation. The abilities of L. curvatus R08 and Leu. mesenteroides [corrected] JK55 to degrade raffinose sugars and, particularly, to produce organic acids from sugar, could contribute to reductions in the anti-nutritional properties of soy, and to the accumulation of compounds with beneficial properties during food processing. Furthermore, this study provides the optimum conditions to induce alpha-Gal from these strains.

The new species Enterobacter oryziphilus sp. nov. and Enterobacter oryzendophyticus sp. nov. are key inhabitants of the endosphere of rice

PubMed Central

2013-01-01

Background Six independent Gram-negative, facultatively anaerobic, non-spore-forming, nitrogen-fixing rod-shaped isolates were obtained from the root endosphere of rice grown at the International Rice Research Institute (IRRI) and investigated in a polyphasic taxonomic study. Results The strains produced fatty acid patterns typical for members of the family Enterobacteriaceae. Comparative sequence analyses of the 16S rRNA as well as rpoB genes allocated the strains to two well-defined groups within the genus Enterobacter, family Enterobacteriaceae. The analyses indicated Enterobacter radicincitans, Enterobacter arachidis and Enterobacter oryzae to be the closest related species. An RpoB (translated) protein comparison supported the placement in the genus Enterobacter and the relatedness of our isolates to the aforementioned species. Genomic DNA:DNA hybridization analyses and biochemical analyses provided further evidence that the novel strains belong to two new species within the genus Enterobacter. The two species can be differentiated from each other and from existing enteric species by acid production from L-rhamnose and D-melibiose, decarboxylation of ornithine and utilization of D-alanine, D-raffinose L-proline and L-aspartic acid, among other characteristics. Members of both species revealed capacities to colonise rice roots, including plant-growth-promoting capabilities such as an active supply of fixed nitrogen to the plant and solubilisation of inorganic phosphorus, next to traits allowing adaptation to the plant. Conclusions Two novel proposed enterobacterial species, denominated Enterobacter oryziphilus sp. nov. (type strain REICA_142T=LMG 26429T=NCCB 100393T) and Enterobacter oryzendophyticus sp. nov. (type strain REICA_082T=LMG 26432T =NCCB 100390T) were isolated from rice roots. Both species are capable of promoting rice growth by supplying nitrogen and phosphorus. PMID:23865888

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

Sugar fermentation in probiotic bacteria--an in vitro study.

PubMed

Hedberg, M; Hasslöf, P; Sjöström, I; Twetman, S; Stecksén-Blicks, C

2008-12-01

Food supplemented with probiotic bacteria is a rapidly growing sector of the market. The aim of the present study was to evaluate and compare the acid production of selected probiotic strains available in commercial products. Six Lactobacillus strains (Lactobacillus plantarum 299v and 931; Lactobacillus rhamnosus GG and LB21; Lactobacillus paracasei subsp. paracasei F19, and Lactobacillus reuteri PTA 5289) were cultivated at 37 degrees C in an anaerobic atmosphere on Man, Rogosa, Shape (MRS) agar for 48 h or MRS broth for 16 h. After centrifugation, the cells were washed and resuspended in sterile phosphate-buffered saline and immediately subjected to a fermentation assay with 12 different carbohydrates (nine sugars and three sugar alcohols) in microtiter plates with a pH indicator. The plates were examined for color changes after 24, 48, and 72 h of incubation under aerobic and anaerobic conditions. Three scores were used: negative (pH > 6.8); weak (pH 5.2-6.8), and positive (pH < 5.2). The strains were characterized with the API 50 CH system to confirm their identity. L. plantarum fermented all the sugars except for melibiose, raffinose, and xylitol. Both L. rhamnosus strains were generally less active although L. rhamnosus GG was slightly more active than strain LB21 in the 5% CO(2) setting. The latter strain exhibited negative reactions for sucrose, maltose, arabinose, and sorbitol under anaerobic conditions. The assays with L. paracasei and L. reuteri had negative or weak reactions for all tested sugars under both aerobic and anaerobic conditions. The metabolic capacity to form acid from dietary sugars differed significantly between the various probiotic strains.

Plasmids with a Chromosome-Like Role in Rhizobia ▿ †

PubMed Central

Landeta, Cristina; Dávalos, Araceli; Cevallos, Miguel Ángel; Geiger, Otto; Brom, Susana; Romero, David

2011-01-01

Replicon architecture in bacteria is commonly comprised of one indispensable chromosome and several dispensable plasmids. This view has been enriched by the discovery of additional chromosomes, identified mainly by localization of rRNA and/or tRNA genes, and also by experimental demonstration of their requirement for cell growth. The genome of Rhizobium etli CFN42 is constituted by one chromosome and six large plasmids, ranging in size from 184 to 642 kb. Five of the six plasmids are dispensable for cell viability, but plasmid p42e is unusually stable. One possibility to explain this stability would be that genes on p42e carry out essential functions, thus making it a candidate for a secondary chromosome. To ascertain this, we made an in-depth functional analysis of p42e, employing bioinformatic tools, insertional mutagenesis, and programmed deletions. Nearly 11% of the genes in p42e participate in primary metabolism, involving biosynthetic functions (cobalamin, cardiolipin, cytochrome o, NAD, and thiamine), degradation (asparagine and melibiose), and septum formation (minCDE). Synteny analysis and incompatibility studies revealed highly stable replicons equivalent to p42e in content and gene order in other Rhizobium species. A systematic deletion analysis of p42e allowed the identification of two genes (RHE_PE00001 and RHE_PE00024), encoding, respectively, a hypothetical protein with a probable winged helix-turn-helix motif and a probable two-component sensor histidine kinase/response regulator hybrid protein, which are essential for growth in rich medium. These data support the proposal that p42e and its homologous replicons (pA, pRL11, pRLG202, and pR132502) merit the status of secondary chromosomes. PMID:21217003

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

Pestoides F, an atypical Yersinia pestis strain from the former Soviet Union.

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

Garcia, Emilio; Worsham, Patricia; Bearden, S.

2007-01-01

Unlike the classical Yersinia pestis strains, members of an atypical group of Y. pestis from Central Asia, denominated Y. pestis subspecies caucasica (also known as one of several pestoides types), are distinguished by a number of characteristics including their ability to ferment rhamnose and melibiose, their lack of the small plasmid encoding the plasminogen activator (pla) and pesticin, and their exceptionally large variants of the virulence plasmid pMT (encoding murine toxin and capsular antigen). We have obtained the entire genome sequence of Y. pestis Pestoides F, an isolate from the former Soviet Union that has enabled us to carryout amore » comprehensive genome-wide comparison of this organism's genomic content against the six published sequences of Y. pestis and their Y. pseudotuberculosis ancestor. Based on classical glycerol fermentation (+ve) and nitrate reduction (+ve) Y. pestis Pestoides F is an isolate that belongs to the biovar antiqua. This strain is unusual in other characteristics such as the fact that it carries a non-consensus V antigen (lcrV) sequence, and that unlike other Pla(-) strains, Pestoides F retains virulence by the parenteral and aerosol routes. The chromosome of Pestoides F is 4,517,345 bp in size comprising some 3,936 predicted coding sequences, while its pCD and pMT plasmids are 71,507 bp and 137,010 bp in size respectively. Comparison of chromosome-associated genes in Pestoides F with those in the other sequenced Y. pestis strains reveals differences ranging from strain-specific rearrangements, insertions, deletions, single nucleotide polymorphisms, and a unique distribution of insertion sequences. There is a single approximately 7 kb unique region in the chromosome not found in any of the completed Y. pestis strains sequenced to date, but which is present in the Y. pseudotuberculosis ancestor. Taken together, these findings are consistent with Pestoides F being derived from the most ancient lineage of Y. pestis yet sequenced.« less

Pestoides F, and Atypical Yersinia pestis Strain from the Former Soviet Union

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

Garcia, E; Worsham, P; Bearden, S

2007-01-05

Unlike the classical Yersinia pestis strains, members of an atypical group of Y. pestis from Central Asia, denominated Y. pestis subspecies caucasica (also known as one of several pestoides types), are distinguished by a number of characteristics including their ability to ferment rhamnose and melibiose, their lacking the small plasmid encoding the plasminogen activator (pla) and pesticin, and their exceptionally large variants of the virulence plasmid pMT (encoding murine toxin and capsular antigen). We have obtained the entire genome sequence of Y. pestis Pestoides F, an isolate from the former Soviet Union that has enabled us to carryout a comprehensivemore » genome-wide comparison of this organism's genomic content against the six published sequences of Y. pestis and their Y. pseudotuberculosis ancestor. Based on classical glycerol fermentation (+ve) and nitrate reduction (+ve) Y. pestis Pestoides F is an isolate that belongs to the biovar antiqua. This strain is unusual in other characteristics such as the fact that it carries a non-consensus V antigen (lcrV) sequence, and that unlike other Pla{sup -} strains, Pestoides F retains virulence by the parenteral and aerosol routes. The chromosome of Pestoides F is 4,517,345 bp in size comprising some 3,936 predicted coding sequences, while its pCD and pMT plasmids are 71,507 bp and 137,010 bp in size respectively. Comparison of chromosome-associated genes in Pestoides F with those in the other sequenced Y. pestis strains, reveals a series of differences ranging from strain-specific rearrangements, insertions, deletions, single nucleotide polymorphisms, and a unique distribution of insertion sequences. There is a single {approx}7 kb unique region in the chromosome not found in any of the completed Y. pestis strains sequenced to date, but which is present in the Y. pseudotuberculosis ancestor. Taken together, these findings are consistent with Pestoides F being derived from the most ancient lineage of Y. pestis yet sequenced.« less

Hydration index--a better parameter for explaining small molecule hydration in inhibition of ice recrystallization.

PubMed

Tam, Roger Y; Ferreira, Sandra S; Czechura, Pawel; Chaytor, Jennifer L; Ben, Robert N

2008-12-24

Several simple mono- and disaccharides have been assessed for their ability to inhibit ice recrystallization. Two carbohydrates were found to be effective recrystallization inhibitors. D-galactose (1) was the best monosaccharide and D-melibiose (5) was the most active disaccharide. The ability of each carbohydrate to inhibit ice growth was correlated to its respective hydration number reported in the literature. A hydration number reflects the number of tightly bound water molecules to the carbohydrate and is a function of carbohydrate stereochemistry. It was discovered that using the absolute hydration number of a carbohydrate does not allow one to accurately predict its ability to inhibit ice recrystallization. Consequently, we have defined a hydration index in which the hydration number is divided by the molar volume of the carbohydrate. This new parameter not only takes into account the number of water molecules tightly bound to a carbohydrate but also the size or volume of a particular solute and ultimately the concentration of hydrated water molecules. The hydration index of both mono- and disaccharides correlates well with experimentally measured RI activity. C-Linked derivatives of the monosaccharides appear to have RI activity comparable to that of their O-linked saccharides but a more thorough investigation is required. The relationship between carbohydrate concentration and RI activity was shown to be noncolligative and a 0.022 M solution of D-galactose (1) and C-linked galactose derivative (10) inhibited recrystallization as well as a 3% DMSO solution. The carbohydrates examined in this study did not possess any thermal hysteresis activity (selective depression of freezing point relative to melting point) or dynamic ice shaping. As such, we propose that they are inhibiting recrystallization at the interface between bulk water and the quasi liquid layer (a semiordered interface between ice and bulk water) by disrupting the preordering of water.

Anaerobium acetethylicum gen. nov., sp. nov., a strictly anaerobic, gluconate-fermenting bacterium isolated from a methanogenic bioreactor.

PubMed

Patil, Yogita; Junghare, Madan; Pester, Michael; Müller, Nicolai; Schink, Bernhard

2015-10-01

A novel strictly anaerobic, mesophilic bacterium was enriched and isolated with gluconate as sole substrate from a methanogenic sludge collected from a biogas reactor. Cells of strain GluBS11T stained Gram-positive and were non-motile, straight rods, measuring 3.0-4.5 × 0.8-1.2 μm. The temperature range for growth was 15-37 °C, with optimal growth at 30 °C, the pH range was 6.5-8.5, with optimal growth at pH 7, and the generation time under optimal conditions was 60 min. API Rapid 32A reactions were positive for α-galactosidase, α-glucosidase and β-glucosidase and negative for catalase and oxidase. A broad variety of substrates was utilized, including gluconate, glucose, fructose, maltose, sucrose, lactose, galactose, melezitose, melibiose, mannitol, erythritol, glycerol and aesculin. Products of gluconate fermentation were ethanol, acetate, formate, H2 and CO2. Neither sulfate nor nitrate served as an electron acceptor. Predominant cellular fatty acids (>10 %) were C14 : 0, C16 : 0, C16 : 1ω7c/iso-C15 : 0 2-OH and C18 : 1ω7c. The DNA G+C content of strain GluBS11T was 44.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequence data revealed that strain GluBS11T is a member of subcluster XIVa within the order Clostridiales. The closest cultured relatives are Clostridium herbivorans (93.1 % similarity to the type strain), Clostridium populeti (93.3 %), Eubacterium uniforme (92.4 %) and Clostridium polysaccharolyticum (91.5 %). Based on this 16S rRNA gene sequence divergence (>6.5 %) as well as on chemotaxonomic and phenotypic differences from these taxa, strain GluBS11T is considered to represent a novel genus and species, for which the name Anaerobium acetethylicum gen. nov., sp. nov. is proposed. The type strain of Anaerobium acetethylicum is GluBS11T ( = LMG 28619T = KCTC 15450T = DSM 29698T).

A Novel Colletotrichum graminicola Raffinose Oxidase in the AA5 Family

PubMed Central

Mollerup, Filip; Parikka, Kirsti; Koutaniemi, Sanna; Boer, Harry; Juvonen, Minna; Master, Emma; Tenkanen, Maija; Kruus, Kristiina

2017-01-01

ABSTRACT We describe here the identification and characterization of a copper radical oxidase from auxiliary activities family 5 (AA5_2) that was distinguished by showing preferential activity toward raffinose. Despite the biotechnological potential of carbohydrate oxidases from family AA5, very few members have been characterized. The gene encoding raffinose oxidase from Colletotrichum graminicola (CgRaOx; EC 1.1.3.−) was identified utilizing a bioinformatics approach based on the known modular structure of a characterized AA5_2 galactose oxidase. CgRaOx was expressed in Pichia pastoris, and the purified enzyme displayed the highest activity on the trisaccharide raffinose, whereas the activity on the disaccharide melibiose was three times lower and more than ten times lower activity was detected on d-galactose at a 300 mM substrate concentration. Thus, the substrate preference of CgRaOx was distinguished clearly from the substrate preferences of the known galactose oxidases. The site of oxidation for raffinose was studied by 1H nuclear magnetic resonance and mass spectrometry, and we confirmed that the hydroxyl group at the C-6 position was oxidized to an aldehyde and that in addition uronic acid was produced as a side product. A new electrospray ionization mass spectrometry method for the identification of C-6 oxidized products was developed, and the formation mechanism of the uronic acid was studied. CgRaOx presented a novel activity pattern in the AA5 family. IMPORTANCE Currently, there are only a few characterized members of the CAZy AA5 protein family. These enzymes are interesting from an application point of view because of their ability to utilize the cheap and abundant oxidant O2 without the requirement of complex cofactors such as FAD or NAD(P). Here, we present the identification and characterization of a novel AA5 member from Colletotrichum graminicola. As discussed in the present study, the bioinformatics approach using the modular structure of galactose oxidase was successful in finding a C-6 hydroxyl carbohydrate oxidase having substrate preference for the trisaccharide raffinose. By the discovery of this activity, the diversity of the CAZy AA5 family is increasing. PMID:28778886

Improving Cotton Embryo Culture by Simulating In Ovulo Nutrient and Hormone Levels

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

Rodney Fuller; Vincent Liddiard; J. Hess

Plant ovules provide zygotes with a physicochemical environment that supports embryo differentiation, growth, and maturation. The exact nature of this embryogenesis-enabling environment is not well characterized, as evidenced by failed attempts to induce normal embryony from zygotes or proembryos (precotyledonary) on defined media. To identify factors required for cotton (Gossypium hirsutum L.) zygotic embryony in vitro, we previously performed chemical and dissolved oxygen tension analyses of cotton ovule fluids and tissues at multiple stages of embryony in situ. Based on these analyses, we report herein the development of procedures that normalize embryo differentiation, growth, maturation, and germination in vitro, startingmore » with proembryos. Our medium differed from Murashige and Skoog (MS) medium as follows (percentage of MS): N (30%, mostly from ten amino acids), P (815%), K (237%), Mg (85%), Ca (267%), S (506%), Fe (88%), and myoinositol (883%). Levels of other MS nutrients and vitamins, except sucrose, were kept at MS levels. Additionally, we included 100 mg L-1 casein hydrolysate plus the following (mmol L-1): d-glucose (1.8), fructose (4.7), sucrose (62.0), arabinose (7.1), melibiose (3.5), malic acid (11.6), and citric acid (3.8). Mannitol was added to achieve a medium osmotic potential of -1.10 MPa, and an atmospheric O2 tension of 3.3 mol m-3 at the surface of embryos was maintained during culture. When cultured on medium containing 8.0 µmol L-1 indole-3-acetic acid, 80-90% of proembryos (as small as 100 cells) of cultivars HS-26 and B-27 increased four- to eightfold in surface area during the first 18 d in culture and germinated thereafter to produce viable plants. Increases in surface area of proembryos cultured on a modified MS medium previously used for somatic embryogenesis were from 0.2- to 0.6-fold. The described embryo culture medium should be useful for studying nutritional and molecular aspects of early embryony and possibly for plant zygote transformation protocols.« less

Metabolite Profiling of adh1 Mutant Response to Cold Stress in Arabidopsis

PubMed Central

Song, Yuan; Liu, Lijun; Wei, Yunzhu; Li, Gaopeng; Yue, Xiule; An, Lizhe

2017-01-01

As a result of global warming, vegetation suffers from repeated freeze-thaw cycles caused by more frequent short-term low temperatures induced by hail, snow, or night frost. Therefore, short-term freezing stress of plants should be investigated particularly in light of the current climatic conditions. Alcohol dehydrogenase (ADH) plays a central role in the metabolism of alcohols and aldehydes and it is a key enzyme in anaerobic fermentation. ADH1 responds to plant growth and environmental stress; however, the function of ADH1 in the response to short-term freezing stress remains unknown. Using real-time quantitative fluorescence PCR, the expression level of ADH1 was analyzed at low temperature (4°C). The lethal temperature was calculated based on the electrolyte leakage tests for both ADH1 deletion mutants (adh1) and wild type (WT) plants. To further investigate the relationship between ADH1 and cold tolerance in plants, low-Mr polar metabolite analyses of Arabidopsis adh1 and WT were performed at cold temperatures using gas chromatography-mass spectrometry. This investigation focused on freezing treatments (cold acclimation group: −6°C for 2 h with prior 4°C for 7 d, cold shock group: −6°C for 2 h without cold acclimation) and recovery (23°C for 24 h) with respect to seedling growth at optimum temperature. The experimental results revealed a significant increase in ADH1 expression during low temperature treatment (4°C) and at a higher lethal temperature in adh1 compared to that in the WT. Retention time indices and specific mass fragments were used to monitor 263 variables and annotate 78 identified metabolites. From these analyses, differences in the degree of metabolite accumulation between adh1 and WT were detected, including soluble sugars (e.g., sucrose) and amino acids (e.g., asparagine). In addition, the correlation-based network analysis highlighted some metabolites, e.g., melibiose, fumaric acid, succinic acid, glycolic acid, and xylose, which enhanced connectedness in adh1 network under cold chock. When considered collectively, the results showed that adh1 possessed a metabolic response to freezing stress and ADH1 played an important role in the cold stress response of a plant. These results expands our understanding of the short-term freeze response of ADH1 in plants. PMID:28123394

Anoxybacter fermentans gen. nov., sp. nov., a piezophilic, thermophilic, anaerobic, fermentative bacterium isolated from a deep-sea hydrothermal vent.

PubMed

Zeng, Xiang; Zhang, Zhao; Li, Xi; Zhang, Xiaobo; Cao, Junwei; Jebbar, Mohamed; Alain, Karine; Shao, Zongze

2015-02-01

A novel piezophilic, thermophilic, anaerobic, fermentative bacterial strain, designated strain DY22613(T), was isolated from a deep-sea hydrothermal sulfide deposit at the East Pacific Rise (GPS position: 102.6° W 3.1° S). Cells of strain DY22613(T) were long, motile rods (10 to 20 µm in length and 0.5 µm in width) with peritrichous flagella and were Gram-stain-negative. Growth was recorded at 44-72 °C (optimum 60-62 °C) and at hydrostatic pressures of 0.1-55 MPa (optimum 20 MPa). The pH range for growth was from pH 5.0 to 9.0 with an optimum at pH 7.0. Growth was observed in the presence of 1 to 8 % (w/v) sea salts and 0.65 to 5.2 % (w/v) NaCl, with optimum salt concentrations at 3.5 % for sea salts and at 2.3 % for NaCl. Under optimal growth conditions, the shortest generation time observed was 27 min (60 °C, 20 MPa). Strain DY22613(T) was heterotrophic, able to utilize complex organic compounds, amino acids, sugars and organic acids including peptone, tryptone, beef extract, yeast extract, alanine, glutamine, methionine, phenylalanine, serine, threonine, fructose, fucose, galactose, gentiobiose, glucose, mannose, melibiose, palatinose, rhamnose, turanose, pyruvate, lactic acid, methyl ester, erythritol, galacturonic acid and glucosaminic acid. Strain DY22613(T) was able to reduce Fe(III) compounds, including Fe(III) oxyhydroxide (pH 7.0), amorphous iron(III) oxide (pH 9.0), goethite (α-FeOOH, pH 12.0), Fe(III) citrate and elementary sulfur. Products of fermentation were butyrate, acetate and hydrogen. Main cellular fatty acids were iso-C15 : 0, iso-C14 : 0 3-OH and C14 : 0. The genomic DNA G+C content of strain DY22613(T) was 36.7 mol%. Based on 16S rRNA gene sequence analysis, the strain forms a novel lineage within the class Clostridia and clusters with the order Haloanaerobiales (86.92 % 16S rRNA gene sequence similarity). The phylogenetic data suggest that the lineage represents at least a novel genus and species, for which the name Anoxybacter fermentans gen. nov., sp. nov. is proposed. The type strain is DY22613(T) ( = JCM 19466(T) = DSM 28033(T) = MCCC 1A06456(T)). © 2015 IUMS.

Vibrio communis sp. nov., isolated from the marine animals Mussismilia hispida, Phyllogorgia dilatata, Palythoa caribaeorum, Palythoa variabilis and Litopenaeus vannamei.

PubMed

Chimetto, Luciane A; Cleenwerck, Ilse; Alves, Nelson; Silva, Bruno Sergio; Brocchi, Marcelo; Willems, Anne; De Vos, Paul; Thompson, Fabiano L

2011-02-01

Eight Vibrio isolates originating from the marine corals Mussismilia hispida and Phyllogorgia dilatata and the zoanthids Palythoa caribaeorum and Palythoa variabilis in Brazil and the Pacific white shrimp (Litopenaeus vannamei) in Ecuador were studied by means of a polyphasic approach. The novel isolates formed a tight monophyletic group in the genus Vibrio and were closely related to species of the Vibrio harveyi group, to which they showed more than 99 % 16S rRNA gene sequence similarity. Analysis based on concatenated sequences of the following seven genes, 16S rRNA, gyrB, recA, rpoA, topA, pyrH and mreB (5633 bp in length), showed clear separation between the isolates and species of the V. harveyi group. Amplified fragment length polymorphism (AFLP) analysis, performed previously, revealed that a representative isolate of this group, LMG 20370, was clearly separate from known Vibrio species (it belonged to the so-called AFLP cluster A31). DNA-DNA hybridization (DDH) experiments with representative isolates and type strains of the V. harveyi species group revealed high DDH between the novel isolates (more than 74 %) and less than 70 % DDH towards type strains of related Vibrio species, proving the novel species status of the isolates. Phenotypically, the novel species belongs to the arginine dihydrolase (A)-negative, lysine decarboxylase (L)-positive and ornithine decarboxylase (O)-positive (A-/L+/O+) cluster reported previously. Most species of the V. harveyi group (i.e. Vibrio rotiferianus, V. harveyi, V. parahaemolyticus and V. alginolyticus) also belong to this A-/L+/O+ cluster. However, several phenotypic features can be used for the identification of the novel species. In contrast to its closest phylogenetic neighbours, the novel species exhibits esterase (C4) and N-acetyl-β-glucosaminidase activities, but it does not produce acetoin, does not use citrate, α-ketoglutaric acid or propionic acid and does not ferment melibiose. The novel species can also be differentiated on the basis of the presence of the fatty acids C(17 : 0,) C(17 : 1)ω8c, iso-C(17 : 0) and iso-C(13 : 0) and the absence of the fatty acid C(18 : 0). The name Vibrio communis sp. nov. is proposed for this taxon. Strain R-40496(T) (=LMG 25430(T) =CAIM 1816(T)) is the type strain.

A novel β-fructofuranosidase in Coleoptera: Characterization of a β-fructofuranosidase from the sugarcane weevil, Sphenophorus levis.

PubMed

Pedezzi, Rafael; Fonseca, Fernando P P; Santos Júnior, Célio Dias; Kishi, Luciano T; Terra, Walter R; Henrique-Silva, Flávio

2014-12-01

β-fructofuranosidases or invertases (EC 3.2.1.26) catalyze the hydrolysis of sucrose into fructose and glucose. β-fructofuranosidases have been widely described in microorganisms, but were not known in the animal kingdom until very recently. There are studies reporting lepidopteran β-fructofuranosidases, but no β-fructofuranosidase gene sequence or encoding transcript has previously been identified in beetles. Considering the scarcity of functional studies on insect β-fructofuranosidases and their apparent non-occurrence among coleopterans, the aim of the present study was to investigate the occurrence and characterize a β-fructofuranosidase transcript identified in a cDNA library from the sugarcane weevil, Sphenophorus levis (Curculionidae). To validate that the β-fructofuranosidase sequence (herein denominated Sl-β-fruct) is indeed encoded by the S. levis genome, PCRs were performed using genomic DNA extracted from the larval fat body as well as DNA from the midgut with microbial content. Amplification of Sl-β-fruct gene using larval fat body DNA indicated its presence in the insect's genomic DNA. The Sl-β-fruct gene was cloned in Pichia pastoris to produce the recombinant enzyme (rSl-β-fruct). Molecular weight of the recombinant protein was about 64 kDa, indicating possible glycosylation, since the theoretical weight was 54.8 kDa. The substrate specificity test revealed that rSl-β-fruct hydrolyzes sucrose and raffinose, but not melibiose or maltose, thereby confirming invertase activity. The pH curve revealed greatest activity at pH 5.0, demonstrating rSl-β-fruct to be an acidic β-fructofuranosidase. Quantitative PCR (qRT-PCR) analyses indicated that the production of mRNA only occurs in the midgut and reaches the greatest expression level in 30-day-old larvae, which is the expected pattern for digestive enzymes. Chromatography of glycosidases from S. levis midguts showed two enzymes acting as β-fructofuranosidase, indicating the presence of a Sl-β-fruct isoform or a β-fructofuranosidase from insect intestinal microbiota. Moreover, it was found that α-glucosidases do not act on sucrose hydrolysis. Phylogenetic analyses indicated this enzyme to be similar to enzymes found in other coleopteran and lepidopteran β-fructofuranosidases, but also closely similar to bacterial enzymes, suggesting potential horizontal gene transfer. Despite this, the enzyme seems to be restricted to different groups of bacteria, which suggests distinct origin events. The present study expands the concept of the occurrence of β-fructofuranosidase in insects. Despite the few descriptions of this gene in the animal kingdom, it is possible to state that β-fructofuranosidase is crucial to the establishment of some insects throughout their evolutionary history, especially members of the Lepidoptera and Coleoptera clades. Copyright © 2014 Elsevier Ltd. All rights reserved.

Trabulsiella guamensis, a new genus and species of the family Enterobacteriaceae that resembles Salmonella subgroups 4 and 5.

PubMed

McWhorter, A C; Haddock, R L; Nocon, F A; Steigerwalt, A G; Brenner, D J; Aleksić, S; Bockemühl, J; Farmer, J J

1991-07-01

In 1985 the vernacular name Enteric Group 90 was coined for a small group of strains that had been referred to our laboratory as probable strains of Salmonella but did not agglutinate in Salmonella typing antisera. By DNA-DNA hybridization (hydroxyapatite method, 32P), seven strains of Enteric Group 90 were found to be closely related (98 to 100% at 60 degrees C and 94 to 100% at 75 degrees C) to the first strain received (0370-85). The relatedness of Enteric Group 90 to 62 strains of other species of the family Enterobacteriaceae was only 6 to 41%, with the highest values obtained with strains of Salmonella, Kluyvera, Shigella, Klebsiella, Enterobacter, and Citrobacter. We propose a new genus, Trabulsiella, with a single new species, Trabulsiella guamensis, for the highly related group of eight strains formerly known as Enteric Group 90. The type strain is designated ATCC 49490 (CDC 0370-85). T. guamensis strains grew well at 36 degrees C and had positive reactions in the following tests: methyl red, citrate utilization (Simmons) (38% positive at day 1, 88% positive at 2 days), H2S production, lysine decarboxylase, arginine dihydrolase (50% positive at 2 days, 100% positive at 7 days), ornithine decarboxylase, motility, growth in KCN medium, mucate fermentation, acetate utilization, nitrate reduction to nitrite, weak tyrosine hydrolysis (88% positive at 2 days, 100% positive at 7 days), and ONPG (o-nitrophenyl-beta-D-galactopyranoside) test. The strains fermented D-glucose with gas production and fermented L-arabinose, cellobiose, D-galactose, D-galacturonate, maltose, D-mannitol, D-mannose, L-rhamnose, D-sorbitol, trehalose, and D-xylose. T. guamensis strains had negative reactions in the following tests: indole production (13% positive), Voges-Proskauer, urea hydrolysis, phenylalanine deaminase, malonate utilization, lipase (corn oil), DNase, oxidase, pigment production, and acid production from adonitol, D-arabitol, dulcitol, erythritol, myo-inositol, melibiose, alpha-methyl-D-glucoside, raffinose, and sucrose. There were delayed positive reactions for gelatin liquefaction (22 degrees C), which was positive at 12 to 23 days, esculin hydrolysis (13% positive at day 1, 50% positive at 7 days), lactose fermentation (13% positive at 3 to 7 days, 100% positive at 8 to 10 days), glycerol fermentation (88% positive at 7 days), and salicin fermentation (13% positive at day 1, 88% positive at 7 days). All strains were susceptible by the disk diffusion method to colistin, nalidixic acid, gentamicin, streptomycin, kanamycin, chloramphenicol, and trimethoprim-sulfamethoxazole, and most strains were susceptible to sulfadiazine (75% susceptible), tetracycline (88%), and carbenicillin (75%). The strains were resistant to penicillin, cephalothin, and ampicillin. The strains were isolated from vacuum cleaner dust (five strains), soil (one strain), and human feces (two strains). Although T. guamensis can occur in human diarrheal stools, there is no evidence that it actually causes diarrhea. Its main interest to clinical microbiologists may be its possible misidentification as a strain Salmonella.