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Sample records for actinomycete strain designated

  1. Isolation and in vitro selection of actinomycetes strains as potential probiotics for aquaculture

    PubMed Central

    Bernal, Milagro García; Campa-Córdova, Ángel Isidro; Saucedo, Pedro Enrique; González, Marlen Casanova; Marrero, Ricardo Medina; Mazón-Suástegui, José Manuel

    2015-01-01

    Aim: This study was designed to describe a series of in vitro tests that may aid the discovery of probiotic strains from actinomycetes. Materials and Methods: Actinomycetes were isolated from marine sediments using four different isolation media, followed by antimicrobial activity and toxicity assessment by the agar diffusion method and the hemolysis of human blood cells, respectively. Extracellular enzymatic production was monitored by the hydrolysis of proteins, lipids and carbohydrates. Tolerance to different pH values and salt concentrations was also determined, followed by hydrophobicity analysis and genetic identification of the most promising strains. Results: Five out of 31 isolated strains showed antimicrobial activity against three Vibrio species. Three non-hemolytic strains (N7, RL8 and V4) among these active isolates yielded positive results in hydrophobicity tests and exhibited good growth at salt concentrations ranging from 0% to 10%, except strain RL8, which required a salt concentration >0.6%. Although these strains did not grow at pH<3, they showed different enzymatic activities. Phylogenetic analysis revealed that strains N7 and V4 have more than 99% identity with several Streptomyces species, whereas the closest matches to strain RL8 are Streptomyces panacagri and Streptomyces flocculus, with 98% and 98.2% similarity, respectively. Conclusion: Three actinomycetes strains showing probiotic-like properties were discovered using several in vitro tests that can be easily implemented in different institutions around the world. PMID:27047067

  2. Biology of Frankia strains, actinomycete symbionts of actinorhizal plants.

    PubMed Central

    Benson, D R; Silvester, W B

    1993-01-01

    Frankia strains are N2-fixing actinomycetes whose isolation and cultivation were first reported in 1978. They induce N2-fixing root nodules on diverse nonleguminous (actinorhizal) plants that are important in ecological successions and in land reclamation and remediation. The genus Frankia encompasses a diverse group of soil actinomycetes that have in common the formation of multilocular sporangia, filamentous growth, and nitrogenase-containing vesicles enveloped in multilaminated lipid envelopes. The relatively constant morphology of vesicles in culture is modified by plant interactions in symbiosis to give a diverse array of vesicles shapes. Recent studies of the genetics and molecular genetics of these organisms have begun to provide new insights into higher-plant-bacterium interactions that lead to productive N2-fixing symbioses. Sufficient information about the relationship of Frankia strains to other bacteria, and to each other, is now available to warrant the creation of some species based on phenotypic and genetic criteria. Images PMID:8336669

  3. Enhanced polyaromatic hydrocarbon degradation by adapted cultures of actinomycete strains.

    PubMed

    Bourguignon, Natalia; Isaac, Paula; Alvarez, Héctor; Amoroso, María J; Ferrero, Marcela A

    2014-12-01

    Fifteen actinomycete strains were evaluated for their potential use in removal of polycyclic aromatic hydrocarbons (PAH). Their capability to degrade of naphthalene, phenanthrene, and pyrene was tested in minimal medium (MM) and MM with glucose as another substrate. Degradation of naphthalene in MM was observed in all isolates at different rates, reaching maximum values near to 76% in some strains of Streptomyces, Rhodococcus sp. 016 and Amycolatopsis tucumanensis DSM 45259. Maximum values of degradation of phenanthrene in MM occurred in cultures of A. tucumanensis DSM 45259 (36.2%) and Streptomyces sp. A12 (20%), while the degradation of pyrene in MM was poor and only significant with Streptomyces sp. A12 (4.3%). Because of the poor performance when growing on phenanthrene and pyrene alone, Rhodococcus sp. 20, Rhodococcus sp. 016, A. tucumanensis DSM 45259, Streptomyces sp. A2, and Streptomyces sp. A12 were challenged to an adaptation schedule of successive cultures on a fresh solid medium supplemented with PAHs, decreasing concentration of glucose in each step. As a result, an enhanced degradation of PAHs by adapted strains was observed in the presence of glucose as co-substrate, without degradation of phenanthrene and pyrene in MM while an increase to up to 50% of degradation was seen with these strains in glucose amended media. An internal fragment of the catA gene, which codes for catechol 1,2-dioxygenase, was amplified from both Rhodococcus strains, showing the potential for degradation of aromatic compounds via salycilate. These results allow us to propose the usefulness of these actinomycete strains for PAH bioremediation in the environment. PMID:25205070

  4. Genome Sequence of Streptomyces viridosporus Strain T7A ATCC 39115, a Lignin-Degrading Actinomycete

    SciTech Connect

    Davis, Jennifer R.; Goodwin, Lynne A.; Teshima, Hazuki; Detter, J. Chris; Tapia, Roxanne; Han, Cliff; Huntemann, Marcel; Wei, Chia-Lin; Han, James; Chen, Amy; Kyrpides, Nikos C; Mavromatis, K; Szeto, Ernest; Markowitz, Victor; Ivanova, N; Mikhailova, Natalia; Ovchinnikova, Galina; Pagani, Ioanna; Pati, Amrita; Woyke, Tanja; Pitluck, Sam; Peters, Lin; Nolan, Matt; Land, Miriam L; Sello, Jason K.

    2013-01-01

    We announce the availability of the genome sequence of Streptomyces viridosporus strain T7A ATCC 39115, a plant biomass- degrading actinomycete. This bacterium is of special interest because of its capacity to degrade lignin, an underutilized compo- nent of plants in the context of bioenergy. It has a full complement of genes for plant biomass catabolism.

  5. Inhibition of Vibrio biofilm formation by a marine actinomycete strain A66.

    PubMed

    You, JianLan; Xue, XiaoLi; Cao, LiXiang; Lu, Xin; Wang, Jian; Zhang, LiXin; Zhou, ShiNing

    2007-10-01

    China remains by far the largest aquaculture producer in the world. However, biofilms formed by pathogenic Vibrio strains pose serious problems to marine aquaculture. To provide a strategy for biofilm prevention, control, and eradication, extracts from 88 marine actinomycetes were screened. Thirty-five inhibited the biofilm formation of Vibrio harveyi, Vibrio vulnificus, and Vibrio anguillarum at a concentration of 2.5% (v/v). Thirty-three of the actinomycete extracts dispersed the mature biofilm. Six extracts inhibited the quorum-sensing system of V. harveyi by attenuating the signal molecules N-acylated homoserine lactones' activity. Strain A66, which was identified as Streptomyces albus, both attenuated the biofilms and inhibited their quorum-sensing system. It is suggested that strain A66 is a promising candidate to be used in future marine aquaculture. PMID:17624525

  6. Chromium(VI) resistance and removal by actinomycete strains isolated from sediments.

    PubMed

    Polti, Marta A; Amoroso, María J; Abate, Carlos M

    2007-03-01

    Forty-one isolated actinomycetes were used to study qualitative and semi-quantitative screening of chromium(VI) resistance. Chromate-removing activity was estimated using the Cr(VI) specific colorimetric reagent 1,5-diphenylcarbazide. Twenty percent of the isolates from El Cadillal (EC) and 14% of isolates from a copper filter plant (CFP) were able to grow at 13 mM of Cr(VI). All isolates from sugar cane (SCP) could grow up to Cr(VI) concentration of 17 mM. EC, CFP and SCP strains were able to remove 24%, 30% and more than 40% of Cr(VI), respectively. The highest and lowest Cr(VI) specific removal values were 75.5 mg g(-1) cell by M3 (CFP), and 1.5 mg g(-1) cell by C35 (EC) strains. Eleven Cr(VI) resistant strains were characterized and identified as species of the genera Streptomyces (10) and Amycolatopsis (1). Differences on actinomycete community composition between contaminated and non-contaminated soil were found. This study showed the potential capacity of actinomycetes as tools for Cr(VI) bioremediation. PMID:17182076

  7. Inhibition of Aspergillus parasiticus and cancer cells by marine actinomycete strains

    NASA Astrophysics Data System (ADS)

    Li, Ping; Yan, Peisheng

    2014-12-01

    Ten actinomycete strains isolated from the Yellow Sea off China's coasts were identified as belonging to two genera by 16S rDNA phylogenetic analysis: Streptomyces and Nocardiopsis. Six Streptomyces strains (MA10, 2SHXF01-3, MA35, MA05-2, MA05-2-1 and MA08-1) and one Nocardiopsis strain (MA03) were predicted to have the potential to produce aromatic polyketides based on the analysis of the KSα (ketoacyl-synthase) gene in the type II PKS (polyketides synthase) gene cluster. Four strains (MA03, MA01, MA10 and MA05-2) exhibited significant inhibitory effects on mycelia growth (inhibition rate >50%) and subsequent aflatoxin production (inhibition rate >75%) of the mutant aflatoxigenic Aspergillus parasiticus NFRI-95. The ethyl acetate extracts of the broth of these four strains displayed significant inhibitory effects on mycelia growth, and the IC50 values were calculated (MA03: 0.275 mg mL-1, MA01: 0.106 mg mL-1, MA10: 1.345 mg mL-1 and MA05-2: 1.362 mg mL-1). Five strains (2SHXF01-3, MA03, MA05-2, MA01 and MA08-1) were selected based on their high cytotoxic activities. The ethyl acetate extract of the Nocardiopsis strain MA03 was particularly noted for its high antitumor activity against human carcinomas of the cervix (HeLa), lung (A549), kidney (Caki-1) and liver (HepG2) (IC50: 2.890, 1.981, 3.032 and 2.603 μg mL-1, respectively). The extract also remarkably inhibited colony formation of HeLa cells at an extremely low concentration (0.5 μg mL-1). This study highlights that marine-derived actinomycetes are a huge resource of compounds for the biological control of aflatoxin contamination and the development of novel drugs for human carcinomas.

  8. Chemical Composition of Cell-Wall Preparations from Strains of Various Form-Genera of Aerobic Actinomycetes

    PubMed Central

    Becker, B.; Lechevalier, M. P.; Lechevalier, H. A.

    1965-01-01

    Cell-wall preparations were made from more than 140 strains of aerobic actinomycetes representing most of the form-genera that have been proposed. All cell-wall preparations contained as major constituents glucosamine, muramic acid, alanine, and glutamic acid. In addition, cell-wall preparations from various types of streptomycetes and strains of Microëllobosporia contained glycine and ll-α,ε-diaminopimelic acid; those from strains of most Actinoplanaceae and micromonosporae contained glycine and meso-α-ε-diaminopimelic acid; those from strains of Thermoactinomyces, Microbispora, Dermatophilus, and nocardiae of the madurae-pelletieri group contained meso-α,ε-diaminopimelic acid; and those from strains of Thermomonospora, Micropolyspora, and most nocardiae contained meso-α,ε-diaminopimelic acid, arabinose, and galactose. All the strains used were also studied morphologically. Images Fig. 1 PMID:14325886

  9. Spontaneous and induced mutations to rifampicin, streptomycin and spectinomycin resistances in actinomycetes: mutagenic mechanisms and applications for strain improvement.

    PubMed

    Baltz, Richard H

    2014-09-01

    Chemical mutagenesis continues to be an important foundational methodology for the generation of highly productive actinomycete strains for the commercial production of antibiotics and other secondary metabolites. In the past, the determination of frequencies of chemically induced resistance to rifampicin (RifR), spectinomycin (SpcR) and streptomycin (StrR) have served as surrogate markers to monitor the efficiencies and robustness of mutagenic protocols. Recent studies indicate that high level RifR, SpcR and StrR phenotypes map to specific regions of the rpoB, rpsE and rpsL genes, respectively, in actinomycetes. Moreover, mutagenesis to RifR can occur spontaneously at many different sites in rpoB, and all six types of base-pair substitutions, as well as in-frame deletions and insertions, have been observed. The RifR/rpoB system provides a robust method to rank mutagenic protocols, to evaluate mutagen specificity and to study spontaneous mutagenesis mechanisms involved in the maintenance of high G+C content in Streptomyces species and other actinomycetes. PMID:25118108

  10. Complete Genome Sequence of Micromonospora Strain L5, a Potential Plant-Growth-Regulating Actinomycete, Originally Isolated from Casuarina equisetifolia Root Nodules

    SciTech Connect

    Hirsch, A. M.; Alvarado, J.; Bruce, D.; Chertkov, O.; De Hoff, P. L.; Detter, J. C.; Fujishige, N. A.; Goodwin, L. A.; Han, J.; Han, S.; Ivanova, N.; Land, M. L.; Lum, M. R.; Milani-Nejad, N.; Nolan, M.; Pati, A.; Pitluck, S.; Tran, S. S.; Woyke, T.; Valdes, M.

    2013-08-29

    Micromonospora species live in diverse environments and exhibit a broad range of functions including antibiotic production, biocontrol, and ability to degrade complex polysaccharides. To learn more about these versatile actinomycetes, we sequenced the genome of strain L5, originally isolated from root nodules of an actinorhizal plant growing in Mexico.

  11. Complete Genome Sequence of Micromonospora Strain L5, a Potential Plant-Growth-Regulating Actinomycete, Originally Isolated from Casuarina equisetifolia Root Nodules

    PubMed Central

    Alvarado, Johana; Bruce, David; Chertkov, Olga; De Hoff, Peter L.; Detter, John C.; Fujishige, Nancy A.; Goodwin, Lynne A.; Han, James; Han, Shunsheng; Ivanova, Natalia; Land, Miriam L.; Lum, Michelle R.; Milani-Nejad, Nima; Nolan, Matt; Pati, Amrita; Pitluck, Sam; Tran, Stephen S.; Woyke, Tanja; Valdés, Maria

    2013-01-01

    Micromonospora species live in diverse environments and exhibit a broad range of functions, including antibiotic production, biocontrol, and degradation of complex polysaccharides. To learn more about these versatile actinomycetes, we sequenced the genome of strain L5, originally isolated from root nodules of an actinorhizal plant growing in Mexico. PMID:24072863

  12. Genome Sequence of Amycolatopsis sp Strain ATCC 39116, a Plant Biomass-Degrading Actinomycete

    SciTech Connect

    Davis, Jennifer R.; Goodwin, Lynne A.; Woyke, Tanja; Teshima, Hazuki; Bruce, David; Detter, J. Chris; Tapia, Roxanne; Han, Shunsheng; Han, James; Pitluck, Sam; Nolan, Matt; Mikhailova, Natalia; Land, Miriam L; Sello, Jason K.

    2012-01-01

    We announce the availability of a high-quality draft of the genome sequence of Amycolatopsis sp. strain 39116, one of few bacterial species that are known to consume the lignin component of plant biomass. This genome sequence will further ongoing efforts to use microorganisms for the conversion of plant biomass into fuels and high-value chemicals.

  13. Genome sequence of Amycolatopsis sp. strain ATCC 39116, a plant biomass-degrading actinomycete.

    PubMed

    Davis, Jennifer R; Goodwin, Lynne A; Woyke, Tanja; Teshima, Hazuki; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, Shunsheng; Han, James; Pitluck, Sam; Nolan, Matt; Mikhailova, Natalia; Land, Miriam L; Sello, Jason K

    2012-05-01

    We announce the availability of a high-quality draft of the genome sequence of Amycolatopsis sp. strain 39116, one of few bacterial species that are known to consume the lignin component of plant biomass. This genome sequence will further ongoing efforts to use microorganisms for the conversion of plant biomass into fuels and high-value chemicals. PMID:22493203

  14. Genome Sequence of the Ethene- and Vinyl Chloride-Oxidizing Actinomycete Nocardioides sp Strain JS614

    SciTech Connect

    Coleman, Nicholas V; Wilson, Neil L; Barry, Kerrie; Bruce, David; Copeland, A; Dalin, Eileen; Detter, J. Chris; Glavina Del Rio, Tijana; Goodwin, Lynne A.; Hammon, Nancy; Han, Shunsheng; Hauser, Loren John; Israni, Sanjay; Kim, Edwin; Kyrpides, Nikos C; Land, Miriam L; Lapidus, Alla L.; Larimer, Frank W; Lucas, Susan; Pitluck, Sam; Richardson, Paul; Schmutz, Jeremy; Tapia, Roxanne; Thompson, Sue; Tice, Hope; Spain, Jim C; Gossett, James G; Mattes, Timothy E

    2011-01-01

    Nocardioides sp. strain JS614 grows on ethene and vinyl chloride (VC) as sole carbon and energy sources and is of interest for bioremediation and biocatalysis. Sequencing of the complete genome of JS614 provides insight into the genetic basis of alkene oxidation, supports ongoing research into the physiology and biochemistry of growth on ethene and VC, and provides biomarkers to facilitate detection of VC/ethene oxidizers in the environment. This is the first genome sequence from the genus Nocardioides and the first genome of a VC/ethene-oxidizing bacterium.

  15. Diversity, bioactivities, and metabolic potentials of endophytic actinomycetes isolated from traditional medicinal plants in Sichuan, China.

    PubMed

    Qiu, Peng; Feng, Zhi-Xiang; Tian, Jie-Wei; Lei, Zu-Chao; Wang, Lei; Zeng, Zhi-Gang; Chu, Yi-Wen; Tian, Yong-Qiang

    2015-12-01

    The present study was designed to determine the taxonomic diversity and metabolic activity of the actinomycetes community, including 13 traditional medicinal plants collected in Sichuan province, China, using multiple approaches such as morphological and molecular identification methods, bioactivity assays, and PCR screening for genes involved in antibiotics biosynthesis. 119 endophytic actinomycetes were recovered; 80 representative strains were chosen for 16S rRNA gene partial sequence analyses, with 66 of them being affiliated to genus Streptomyces and the remaining 14 strains being rare actinomycetes. Antimicrobial tests showed that 12 (15%) of the 80 endophytic actinomycetes displayed inhibitory effects against at least one indicator pathogens, which were all assigned to the genus Streptomyces. In addition, 87.5% and 58.8% of the isolates showed anticancer and anti-diabetic activities, respectively. Meanwhile, the anticancer activities of the isolates negatively correlated with their anti-diabetic activities. Based on the results of PCR screening, five genes, PKS-I, PKS-II, NRPS, ANSA, and oxyB, were detected in 55.0%, 58.8%, 90.0%, 18.8% and 8.8% of the 80 actinomycetes, respectively. In conclusion, the PCR screening method employed in the present study was conducive for screening and selection of potential actinomycetes and predicting potential secondary metabolites, which could overcome the limitations of traditional activity screening models. PMID:26721714

  16. Isolation of cellulolytic actinomycetes from marine sediments

    SciTech Connect

    Veiga, M.; Esparis, A.; Fabregas, J.

    1983-07-01

    The cellulolytic activity of 36 actinomycetes strains isolated from marine sediments was investigated by the cellulose-azure method. Approximately 50% of the isolates exhibited various degrees of cellulolytic activity. 13 references.

  17. Sequence-Based Identification of Aerobic Actinomycetes

    PubMed Central

    Patel, Jean Baldus; Wallace, Richard J.; Brown-Elliott, Barbara A.; Taylor, Tony; Imperatrice, Carol; Leonard, Deborah G. B.; Wilson, Rebecca W.; Mann, Linda; Jost, Kenneth C.; Nachamkin, Irving

    2004-01-01

    We investigated the utility of 500-bp 16S rRNA gene sequencing for identifying clinically significant species of aerobic actinomycetes. A total of 28 reference strains and 71 clinical isolates that included members of the genera Streptomyces, Gordonia, and Tsukamurella and 10 taxa of Nocardia were studied. Methods of nonsequencing analyses included growth and biochemical analysis, PCR-restriction enzyme analysis of the 439-bp Telenti fragment of the 65 hsp gene, susceptibility testing, and, for selected isolates, high-performance liquid chromatography. Many of the isolates were included in prior taxonomic studies. Sequencing of Nocardia species revealed that members of the group were generally most closely related to the American Type Culture Collection (ATCC) type strains. However, the sequences of Nocardia transvalensis, N. otitidiscaviarum, and N. nova isolates were highly variable; and it is likely that each of these species contains multiple species. We propose that these three species be designated complexes until they are more taxonomically defined. The sequences of several taxa did not match any recognized species. Among other aerobic actinomycetes, each group most closely resembled the associated reference strain, but with some divergence. The study demonstrates the ability of partial 16S rRNA gene sequencing to identify members of the aerobic actinomycetes, but the study also shows that a high degree of sequence divergence exists within many species and that many taxa within the Nocardia spp. are unnamed at present. A major unresolved issue is the type strain of N. asteroides, as the present one (ATCC 19247), chosen before the availability of molecular analysis, does not represent any of the common taxa associated with clinical nocardiosis. PMID:15184431

  18. Distribution of β-Lactamases in Actinomycetes

    PubMed Central

    Ogawara, Hiroshi; Kawamura, Nao; Kudo, Takuji; Suzuki, Ken-Ichiro; Nakase, Takashi

    1999-01-01

    The distribution of β-lactamase activities in a collection of actinomycete strains was surveyed. Six of 127 strains were found to produce β-lactamase. This low frequency was in contrast to the case with Streptomyces species. The producing strains were not related phylogenetically. MICs of benzylpenicillin did not correlate with β-lactamase production. PMID:10582901

  19. Effectiveness and toxicity of a novel isolated actinomycete strain Streptomyces sp. JS01 on a harmful alga Phaeocystis globosa.

    PubMed

    Zhang, Huajun; Zhang, Su; Peng, Yun; Li, Yi; Cai, Guanjing; Chen, Zhangran; Zheng, Wei; Tian, Yun; Xu, Hong; Zheng, Tianling

    2015-06-01

    An aquatic actinomycete capable of eliminating the brown tide causing marine alga Phaeocystis globosa was isolated from the surface sea water and the isolate named JS01 was characterized as Streptomyces on the basis of its 16S rRNA gene sequence. The supernatant of JS01 could lyse algal cells, implying that JS01 produced a latent alga-lytic compound. Considering this algicidal activity and the response of the algal cells, Chlorophyll a fluorescence decreased significantly in P. globosa in response to the JS01 supernatant when analyzed with flow cytometry. The algal cells experienced cell shrinkage and plasmolysis before disintegration after 72 h of treatment. The released algicide(s) were heat-tolerant, except above 121 °C, and fluctuation in pH variations; even so, algicidal activity was also over 60 %. The maximum toxicity of JS01 was on the seventh day of culture, and the relative luminosity was 0.49 at that time when detected by luminous bacteria Vibrio fischeri. These results indicated that the Streptomyces sp. JS01 could function as a potential controller of Phaeocystis globosa blooms. PMID:25638354

  20. Complete genome sequence of Streptomyces sp. strain CFMR 7, a natural rubber degrading actinomycete isolated from Penang, Malaysia.

    PubMed

    Nanthini, Jayaram; Chia, Kim-Hou; Thottathil, Gincy P; Taylor, Todd D; Kondo, Shinji; Najimudin, Nazalan; Baybayan, Primo; Singh, Siddharth; Sudesh, Kumar

    2015-11-20

    Streptomyces sp. strain CFMR 7, which naturally degrades rubber, was isolated from a rubber plantation. Whole genome sequencing and assembly resulted in 2 contigs with total genome size of 8.248 Mb. Two latex clearing protein (lcp) genes which are responsible for rubber degrading activities were identified. PMID:26376470

  1. High-molecular-mass multicatalytic proteinase complexes produced by the nitrogen-fixing actinomycete Frankia strain BR.

    PubMed Central

    Benoist, P; Müller, A; Diem, H G; Schwencke, J

    1992-01-01

    A major-high-molecular mass proteinase and seven latent minor proteinases were found in cell extracts and in concentrates of culture medium from Frankia sp. strain BR after nondenaturing electrophoresis in mixed gelatin-polyacrylamide gels. All of these complexes showed multicatalytic properties. Their molecular masses and their sedimentation coefficients varied from 1,300 kDa (28S) to 270 kDa (12S). The electroeluted 1,300-kDa proteinase complex dissociated into 11 low-molecular-mass proteinases (40 to 19 kDa) after sodium dodecyl sulfate activation at 30 degrees C and electrophoresis under denaturing conditions. All of these electroeluted proteinases hydrolyzed N-carbobenzoxy-Pro-Ala-Gly-Pro-4-methoxy-beta- naphthylamide, D-Val-Leu-Arg-4-methoxy-beta-naphthylamide, and Boc-Val-Pro-Arg-4-methyl-7-coumarylamide, whereas Suc-Leu-Leu-Val-Tyr-4-methyl-7-coumarylamide was cleaved only by the six lower-molecular-mass proteinases (27.5 to 19 kDa). Examination by electron microscopy of uranyl acetate-stained, electroeluted 1,300- and 650-kDa intracellular and extracellular proteinase complexes showed ring-shaped and cylindrical particles (10 to 11 nm in diameter, 15 to 16 nm long) similar to those of eukaryotic prosomes and proteasomes. Polyclonal antibodies raised against rat skeletal muscle proteasomes cross-reacted with all of the high-molecular-mass proteinase complexes and, after denaturation of the electroeluted 1,300-kDa band, with polypeptides of 35 to 38, 65, and 90 kDa. Electrophoresis of the activated cell extracts under denaturing conditions revealed 11 to 17 gelatinases from 40 to 19 kDa, including the 11 proteinases of the 1,300-kDa proteinase complex. The inhibition pattern of these proteinases is complex. Thiol-reactive compounds and 1-10-phenanthroline strongly inhibited all of the proteinases, but inhibitors against serine-type proteinases were also effective for most of them. Images PMID:1537794

  2. Genetic Screening Strategy for Rapid Access to Polyether Ionophore Producers and Products in Actinomycetes ▿ †

    PubMed Central

    Wang, Hao; Liu, Ning; Xi, Lijun; Rong, Xiaoying; Ruan, Jisheng; Huang, Ying

    2011-01-01

    Polyether ionophores are a unique class of polyketides with broad-spectrum activity and outstanding potency for the control of drug-resistant bacteria and parasites, and they are produced exclusively by actinomycetes. A special epoxidase gene encoding a critical tailoring enzyme involved in the biosynthesis of these compounds has been found in all five of the complete gene clusters of polyether ionophores published so far. To detect potential producer strains of these antibiotics, a pair of degenerate primers was designed according to the conserved regions of the five known polyether epoxidases. A total of 44 putative polyether epoxidase gene-positive strains were obtained by the PCR-based screening of 1,068 actinomycetes isolated from eight different habitats and 236 reference strains encompassing eight major families of Actinomycetales. The isolates spanned a wide taxonomic diversity based on 16S rRNA gene analysis, and actinomycetes isolated from acidic soils seemed to be a promising source of polyether ionophores. Four genera were detected to contain putative polyether epoxidases, including Micromonospora, which has not previously been reported to produce polyether ionophores. The designed primers also detected putative epoxidase genes from diverse known producer strains that produce polyether ionophores unrelated to the five published gene clusters. Moreover, phylogenetic and chemical analyses showed a strong correlation between the sequence of polyether epoxidases and the structure of encoded polyethers. Thirteen positive isolates were proven to be polyether ionophore producers as expected, and two new analogues were found. These results demonstrate the feasibility of using this epoxidase gene screening strategy to aid the rapid identification of known products and the discovery of unknown polyethers in actinomycetes. PMID:21421776

  3. Nocardia pigrifrangens sp. nov., a novel actinomycete isolated from a contaminated agar plate.

    PubMed

    Wang, Liming; Zhang, Yamei; Huang, Ying; Maldonado, Luis A; Liu, Zhiheng; Goodfellow, Michael

    2004-09-01

    A polyphasic study was undertaken to establish the taxonomic position of an actinomycete strain isolated from a contaminated agar plate. The strain, designated 7031T, had morphological and chemotaxonomic properties typical of the genus Nocardia. An almost-complete 16S rRNA gene sequence determined for the strain was aligned with available sequences for nocardiae, and phylogenetic trees were inferred using three tree-generating algorithms. Strain 7031T clustered with the type strains of Nocardia carnea and Nocardia flavorosea, showing low 16S rRNA gene sequence similarities to these species (97.2 and 97.5 %, respectively). The strain was also distinguished from the closest species by a range of phenotypic properties. It is proposed that the strain be recognized as a novel species of Nocardia, Nocardia pigrifrangens sp. nov., the type strain of which is 7031T (= AS 4.1808T = JCM 11884T). PMID:15388728

  4. Screening Actinomycetes for Extracellular Peroxidase Activity

    PubMed Central

    Mercer, D. K.; Iqbal, M.; Miller, P.; McCarthy, A. J.

    1996-01-01

    A diverse collection of actinomycete strains were screened for production of extracellular peroxidase activity by adapting a chemiluminescence analysis system developed for horseradish peroxidase-based enzyme-linked immunosorbent assay. Extracellular peroxidase activity was found to be common but quantitatively variable, and this rapid and sensitive screening system permitted identification of a small group of high-producing strains. A range of spectrophotometric assays were compared for the measurement of peroxidase activity in concentrated culture supernatants of two selected thermophilic streptomycetes. Of these, the peroxide-dependent oxidation of 2,4-dichlorophenol was identified as the most robust and reproducible assay for quantitative studies. PMID:16535344

  5. Antimicrobial potential of Actinomycetes species isolated from marine environment

    PubMed Central

    Valli, S; Suvathi, Sugasini S; Aysha, OS; Nirmala, P; Vinoth, Kumar P; Reena, A

    2012-01-01

    Objective To evaluate the antimicrobial activity of Actinomycetes species isolated from marine environment. Methods Twenty one strains of Actinomycetes were isolated from samples of Royapuram, Muttukadu, Mahabalipuram sea shores and Adyar estuary. Preliminary screening was done using cross-streak method against two gram-positive and eight gram-negative bacteria. The most potent strains C11 and C12 were selected from which antibacterial substances were extracted. The antibacterial activities of the extracts were performed using Kirby-Bauer disc diffusion method. Molecular identification of those isolates was done. Results All those twenty one isolates were active against at least one of the test organisms. Morphological characters were recorded. C11 showed activity against Staphylococcus species (13.0±0.5 mm), Vibrio harveyi (11.0±0.2 mm), Pseudomonas species (12.0±0.3 mm). C12 showed activity against Staphylococcus species (16.0±0.4 mm), Bacillus subtilis (11.0±0.2 mm), Vibrio harveyi (9.0±0.1 mm), Pseudomonas species (10.0±0.2 mm). 16S rRNA pattern strongly suggested that C11 and C12 strains were Streptomyces species. Conclusions The results of the present investigation reveal that the marine Actinomycetes from coastal environment are the potent source of novel antibiotics. Isolation, characterization and study of Actinomycetes can be useful in discovery of novel species of Actinomycetes. PMID:23569952

  6. [Isolation and antimicrobial activities of actinomycetes from vermicompost].

    PubMed

    Wang, Xue-jun; Yan, Shuang-lin; Min, Chang-li; Yang, Yan

    2015-02-01

    In this paper, actinomycetes were isolated from vermicompost by tablet coating method. Antimicrobial activities of actinomycetes were measured by the agar block method. Strains with high activity were identified based on morphology and biochemical characteristics, as well as 16S rDNA gene sequence analysis. The results showed that 26 strains of actinomycetes were isolated, 16 of them had antimicrobial activities to the test strains which accounts for 61.54% of all strains. Among the 16 strains, the strain QYF12 and QYF22 had higher antimicrobial activity to Micrococcus luteus, with a formed inhibition zone of 27 mm and 31 mm, respectively. While the strain QYF26 had higher antimicrobial activity to Bacillus subtilis, and the inhibition zone diameter was 21 mm. Based on the identification of strains with high activity, the strain QYF12 was identified as Streptomyces chartreusis, the strain QYF22 was S. ossamyceticus and the strain QYF26 was S. gancidicus. This study provided a theoretical basis for further separate antibacterial product used for biological control. PMID:26137678

  7. Moderately haloalkaliphilic actinomycetes in salt-affected soils

    NASA Astrophysics Data System (ADS)

    Zvyagintsev, D. G.; Zenova, G. M.; Oborotov, G. V.

    2009-12-01

    It was found that the population density of actinomycetes in solonchaks and saline desert soils varied from hundreds to tens of thousands of colony-forming units (CFUs) per 1 g of soil depending on soil type and was by 1-3 orders of magnitude lower than the number of mycelial bacteria in main soil types. Actinomycetes grow actively in saline soils, and the length of their mycelium reaches 140 m per 1 g of soil. Domination of moderately halophilic, alkaliphilic, and haloalkaliphilic actinomycetes, which grow well under 5% NaCl and pH 8-9, is a specific feature of actinomycetal complexes in saline soils. Representatives of Streptomyces and Micromonospora genera were found among the haloalkaliphilic actinomycetes. Micromonospores demonstrated lower (than streptomycetes) adaptability to high salt concentrations. Investigation of the phylogenetic position of isolated dominant haloalkaliphilic strains of streptomycetes performed on the basis of sequencing of the gene 16S rRNA enabled identifying these strains as Streptomyces pluricolorescens and S. prunicolor.

  8. Evolution of cyclizing 5-aminolevulinate synthases in the biosynthesis of actinomycete secondary metabolites: outcomes for genetic screening techniques

    PubMed Central

    Petříčková, Kateřina; Chroňáková, Alica; Zelenka, Tomáš; Chrudimský, Tomáš; Pospíšil, Stanislav; Petříček, Miroslav; Krištůfek, Václav

    2015-01-01

    A combined approach, comprising PCR screening and genome mining, was used to unravel the diversity and phylogeny of genes encoding 5-aminolevulinic acid synthases (ALASs, hemA gene products) in streptomycetes-related strains. In actinomycetes, these genes were believed to be directly connected with the production of secondary metabolites carrying the C5N unit, 2-amino-3-hydroxycyclopent-2-enone, with biological activities making them attractive for future use in medicine and agriculture. Unlike “classical” primary metabolism ALAS, the C5N unit-forming cyclizing ALAS (cALAS) catalyses intramolecular cyclization of nascent 5-aminolevulinate. Specific amino acid sequence changes can be traced by comparison of “classical” ALASs against cALASs. PCR screening revealed 226 hemA gene-carrying strains from 1,500 tested, with 87% putatively encoding cALAS. Phylogenetic analysis of the hemA homologs revealed strain clustering according to putative type of metabolic product, which could be used to select producers of specific C5N compound classes. Supporting information was acquired through analysis of actinomycete genomic sequence data available in GenBank and further genetic or metabolic characterization of selected strains. Comparison of 16S rRNA taxonomic identification and BOX-PCR profiles provided evidence for numerous horizontal gene transfers of biosynthetic genes or gene clusters within actinomycete populations and even from non-actinomycete organisms. Our results underline the importance of environmental and evolutionary data in the design of efficient techniques for identification of novel producers. PMID:26300877

  9. Design parameters for borehole strain instrumentation

    NASA Astrophysics Data System (ADS)

    Gladwin, Michael T.; Hart, Rhodes

    1985-01-01

    The response of a borehole strain meter to hydrostatic and shear deformations in an isotropic medium is calculated to facilitate optimum instrument design and produce instrument response factors for parameters typically encountered in installed instruments. Results for an empty borehole are first compared with results for an instrument in intimate contact with the surrounding rock. The effects of the grout used to install the instrument are then examined. Where possible, analytic forms for the response factors are given. Results for typical installations are then presented in graphical form for optimizing instrument design in an environment of known elastic parameters. Alternatively, the results may be applied in the measurement of unknown strain signals, to correct for instrument response or to provide in-situ estimates of the elastic properties of the environment by examination of observed strain response to known strain signals.

  10. Antibiotics production by an actinomycete isolated from the termite gut.

    PubMed

    Matsui, Toru; Tanaka, Junichi; Namihira, Tomoyuki; Shinzato, Naoya

    2012-12-01

    As well as the search for new antibiotics, a new resource or strains for the known antibiotics is also important. Microbial symbionts in the gut of termites could be regarded as one of the feasible resource for such purpose. In this study, antibiotic-producing actinomycetes were screened from symbionts of the termite gut. 16SrRNA sequence analysis for the 10 isolates revealed that they belong to actinomycetes such as Streptomyces sp., Kitasatospora sp., and Mycobacterium sp. A culture broth from one of the isolate, namely strain CA1, belonging to the genera Streptomyces exhibited antagonistic activity against actinomycetes (Micrococcus spp.), gram-positive bacteria (Bacillus spp.), and yeast (Candida spp.). The structures of 2 compounds isolated from the culture broth of the strain CA1 were identified as those of actinomycin X2 and its analog, D. This study is the first to report that some symbionts of the termite gut are antibiotic-producing actinomycetes, and suggest that the termite gut is a feasible resource for bioprospecting. PMID:22359219

  11. Actinomycetes inhibit filamentous fungi from the cuticle of Acromyrmex leafcutter ants.

    PubMed

    Dângelo, Rômulo Augusto Cotta; de Souza, Danival José; Mendes, Thais Demarchi; Couceiro, Joel da Cruz; Lucia, Terezinha Maria Castro Della

    2016-03-01

    Actinomycetes bacteria associated with leafcutter ants produce secondary metabolites with antimicrobial properties against Escovopsis, a fungus specialized in attacking the gardens of fungus-growing ants, which denies the ants their food source. Because previous studies have used fungi isolated from fungus gardens but not from ant integument, the aims of the present study were to isolate actinomycetes associated with the cuticle of the Acromyrmex spp. and to quantify their inhibition abilities against the filamentous fungal species carried by these ants. The results demonstrated that actinomycetes had varied strain-dependent effects on several filamentous fungal species in addition to antagonistic activity against Escovopsis. The strain isolated from Acromyrmex balzani was identified as a Streptomyces species, whereas the remaining isolates were identified as different strains belonging to the genus Pseudonocardia. These findings corroborate the hypothesis that actinomycetes do not act specifically against Escovopsis mycoparasites and may have the ability to inhibit other species of pathogenic fungi. PMID:26805489

  12. Isolation and identification of actinomycetes from a compost-amended soil with potential as biocontrol agents.

    PubMed

    Cuesta, Gonzalo; García-de-la-Fuente, Rosana; Abad, Manuel; Fornes, Fernando

    2012-03-01

    The search for new biocontrol strategies to inhibit the growth of phytopathogenic microorganisms has become widely widespread due to environmental concerns. Among actinomycetes, Streptomyces species have been extensively studied since they have been recognized as important sources of antibiotics. Actinomycete strains were isolated from a calcareous soil, 2 two-phase olive mill waste ('alperujo') composts, and the compost-amended soil by using selective media, and they were then co-cultured with 5 phytopathogenic fungi and 1 bacterium to perform an in vitro antagonism assay. Forty-nine actinomycete strains were isolated, 12 of them showing a great antagonistic activity towards the phytopathogenic microorganisms tested. Isolated strains were identified by 16S rDNA sequence analysis and phenotypic procedures. Eleven isolates concerned the genus Streptomyces and 1 actinomycete with chitinolytic activity belonged to the genus Lechevalieria. PMID:21190787

  13. Whole-Genome Shotgun Sequencing of Rhodococcus erythropolis Strain P27, a Highly Radiation-Resistant Actinomycete from Antarctica

    PubMed Central

    Gouvêa Taketani, Rodrigo; Domingues Zucchi, Tiago; Soares de Melo, Itamar

    2013-01-01

    Here, we report the draft genome sequence of radiation-resistant Rhodococcus erythropolis strain P27, isolated from leaves of Deschampsia antarctica Desv. (Poaceae) in the Admiralty Bay area, Antarctica. PMID:24072865

  14. Streptomyces lopnurensis sp. nov., an actinomycete isolated from soil.

    PubMed

    Zheng, Bei; Han, Xiao-Xue; Xia, Zhan-Feng; Wan, Chuan-Xing; Zhang, Li-Li

    2014-12-01

    A novel actinomycete, designated strain TRM 49590(T), was isolated from a soil sample from Lop Nur in Xinjiang Province, China. Strain TRM 49590(T) was aerobic, Gram-staining-positive, with an optimum NaCl concentration for growth of 1.5 % (w/v) and an optimum temperature for growth of 28-37 °C. The aerial mycelium was sparse, cylindrical and smooth-surfaced with irregular branches on ISP medium 4. The whole-cell sugars of strain TRM 49590(T) were ribose and glucose. The diagnostic diamino acid contained ll-diaminopimelic acid. The predominant menaquinones were MK-9(H6) and MK-9(H8), with MK-9(H4) and MK-10(H6) present in smaller amounts. The major fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The G+C content of the genomic DNA was 62.2 mol%. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol and phosphatidylinositol mannoside. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain TRM 49590(T) belongs to the genus Streptomyces with a sequence similarity of 97.16 % with the most closely related species Streptomyces sodiiphilus. Based on these observations, strain TRM 49590(T) is proposed to represent a novel species of the genus Streptomyces for which the name Streptomyces lopnurensis sp. nov. is suggested. The type strain is TRM 49590(T) ( = CCTCC AA 2013018(T) = NRRL B59109(T)). PMID:25253072

  15. Natural Products from Mangrove Actinomycetes

    PubMed Central

    Xu, Dong-Bo; Ye, Wan-Wan; Han, Ying; Deng, Zi-Xin; Hong, Kui

    2014-01-01

    Mangroves are woody plants located in tropical and subtropical intertidal coastal regions. The mangrove ecosystem is becoming a hot spot for natural product discovery and bioactivity survey. Diverse mangrove actinomycetes as promising and productive sources are worth being explored and uncovered. At the time of writing, we report 73 novel compounds and 49 known compounds isolated from mangrove actinomycetes including alkaloids, benzene derivatives, cyclopentenone derivatives, dilactones, macrolides, 2-pyranones and sesquiterpenes. Attractive structures such as salinosporamides, xiamycins and novel indolocarbazoles are highlighted. Many exciting compounds have been proven as potential new antibiotics, antitumor and antiviral agents, anti-fibrotic agents and antioxidants. Furthermore, some of their biosynthetic pathways have also been revealed. This review is an attempt to consolidate and summarize the past and the latest studies on mangrove actinomycetes natural product discovery and to draw attention to their immense potential as novel and bioactive compounds for marine drugs discovery. PMID:24798926

  16. Streptomyces aidingensis sp. nov., an actinomycete isolated from lake sediment.

    PubMed

    Xia, Zhan-Feng; Ruan, Ji-Sheng; Huang, Ying; Zhang, Li-Li

    2013-09-01

    A novel actinomycete strain, designated TRM 46012(T), was isolated from sediment of Aiding Lake in Tulufan Basin (42° 64' N 89° 26' E), north-west China. The strain was aerobic and Gram-staining-positive with an optimum NaCl concentration for growth of 0-5% (w/v). The isolate had sparse aerial mycelium and produced bud-shaped spores at the end of the aerial mycelium on ISP medium 4. The isolate contained ll-diaminopimelic acid as the diagnostic diamino acid and ribose as the major whole-cell sugar. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannoside, one unidentified phospholipid and three unidentified glycolipids. The predominant menaquinones were MK-9(H₆), MK-9(H₈) and MK-9(H₄). The major fatty acids were iso-C(16:0), anteiso-C(17:0) and anteiso-C(15:0). The G+C content of the DNA was 74.4 mol%. Phylogenetic analysis showed that strain TRM 46012(T) had 16S rRNA gene sequence similarity of 95.7% with the most closely related species with a validly published name, Streptomyces cheonanensis, and it could be distinguished from all species in the genus Streptomyces by using the data from this polyphasic taxonomic study. On the basis of these data, strain TRM 46012(T) should be designated as a representative of a novel species of the genus Streptomyces, for which the name Streptomyces aidingensis sp. nov. is proposed. The type strain is TRM 46012(T) ( =CGMCC 4.5739(T) =NBRC 108211(T)). PMID:23456804

  17. [Study of natural mutiple drug resistance in actinomycetes of the genus Streptomyes].

    PubMed

    Puzynina, G G; Danilenko, V N; Lomovskaia, N D; Trenina, G A

    1977-10-01

    Natural strains of actinomycetes belonging to 3 systematic groups of the Streptomyces genera, i.e. blue, gray and globisporine were characterized for their resistance to antibiotics and sulfamids. The majority of the strains were shown to have stable inherited multiple resistence to a wide variety of antibiotics. Linkage analysis for resistance determinants in pairs showed random distribution of most of the determinants among the members of the blue and grey groups of the actinomycetes. Non-random distribution of the resistance determinants to Tc, Cm and Rm in TcCm, TcRm conbinations for the blue group actinomycetes and to Om, Rm, Fa, Lm, Em, Rm and Tc in OmRm, FaLm, EmPm, TcOm combinations among the members of the grey group of actinomycetes was found. PMID:921232

  18. Diversity of Aquatic Actinomycetes in Lakes of the Middle Plateau, Yunnan, China

    PubMed Central

    Jiang, C.; Xu, L.

    1996-01-01

    A total of 749 sediment and water samples were collected from 12 lakes of the Middle Plateau of Yunnan from 1983 to 1993. The diversity and biological characteristics of the aquatic actinomycetes in these lakes were studied. Sixteen genera of actinomycetes were isolated from these samples. Micromonospores assumed a notable dominance (from 39 to 89%) in the actinomycete populations of these lake sediments. Streptomycetes were the second most abundant organisms. The diversity and counts of actinomycetes varied with the season. Thermophilic actinomycetes have a wide distribution in these lakes, but their counts were smaller. The cell wall compositions of certain Micromonospora and Streptomyces strains from an alkaline lake revealed an unusual combination of glycine and isomers of diaminopimelic acid. It seems that aquatic actinomycetes play a significant role in the decomposition of organic substances, including some toxic compounds such as phenol, in these lakes. It also appears that aquatic actinomycetes are one of the important resources for screening useful enzymes and metabolites. PMID:16535213

  19. Design of minimally strained nucleic Acid nanotubes.

    PubMed

    Sherman, William B; Seeman, Nadrian C

    2006-06-15

    A practical theoretical framework is presented for designing and classifying minimally strained nucleic acid nanotubes. The structures are based on the double crossover motif where each double-helical domain is connected to each of its neighbors via two or more Holliday-junction-like reciprocal exchanges, such that each domain is parallel to the main tube axis. Modeling is based on a five-parameter characterization of the segmented double-helical structure. Once the constraint equations have been derived, the primary design problem for a minimally strained N-domain structure is reduced to solving three simultaneous equations in 2N+2 variables. Symmetry analysis and tube merging then allow for the design of a wide variety of tubes, which can be tailored to satisfy requirements such as specific inner and outer radii, or multiple lobed structures. The general form of the equations allows similar techniques to be applied to various nucleic acid helices: B-DNA, A-DNA, RNA, DNA-PNA, or others. Possible applications for such tubes include nanoscale scaffolding as well as custom-shaped enclosures for other nano-objects. PMID:16581842

  20. Entomopathogenic marine actinomycetes as potential and low-cost biocontrol agents against bloodsucking arthropods.

    PubMed

    Loganathan, Karthik; Kumar, Gaurav; Kirthi, Arivarasan Vishnu; Rao, Kokati Venkata Bhaskara; Rahuman, Abdul Abdul

    2013-11-01

    A novel approach to control strategies for integrated blood-feeding parasite management is in high demand, including the use of biological control agents. The present study aims to determine the efficacy of optimized crude extract of actinomycetes strain LK1 as biological control agent against the fourth-instar larvae of Anopheles stephensi and Culex tritaeniorhynchus (Diptera: Culicidae) and adults of Haemaphysalis bispinosa, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae), and Hippobosca maculata (Diptera: Hippoboscidae). Antiparasitic activity was optimized using the Plackett-Burman method, and the design was developed using the software Design-Expert version 8.0.7.1. The production of the optimized crude actinomycetes LK1 strain extract was performed using response surface methodology to optimize the process parameters of protease inhibitor activity of marine actinobacteria for the independent variables like pH, temperature, glucose, casein, and NaCl at two levels (-1 and +1). The potential actinomycetes strain was identified as Saccharomonas spp., and the metamodeling surface simulation procedure was followed. It was studied using a computer-generated experimental design, automatic control of simulation experiments, and sequential optimization of the metamodels fitted to a simulation response surface function. The central composite design (CCD) used for the analysis of treatment showed that a second-order polynomial regression model was in good agreement with the experimental results at R (2) = 0.9829 (p < 0.05). The optimized values of the variables for antioxidant production were pH 6.00, glucose 1.3%, casein 0.09%, temperature 31.23 °C, and NaCl 0.10%. The LK1 strain-optimized crude extract was purified using reversed-phase high-pressure liquid chromatography, and the isolated protease inhibitor showed antiparasitic activity. The antiparasitic activity of optimized crude extract of LK1 was tested against larvae of A. stephensi (LC₅₀ = 31.82 ppm

  1. [Distribution and characteristics of soil antagonistic actinomycetes on northern slope of Taibai Mountain, Qinling].

    PubMed

    Zhu, Wen-Jie; Xue, Quan-Hong; Cao, Yan-Ru; Xue, Lei; Shen, Guang-Hui; Lai, Hang-Xian

    2011-11-01

    Twelve representative soil samples were collected from different altitudes on the northern slope of Taibai Mountain to study the distribution and characteristics of soil antagonistic actinomyces by using agar block method. There existed a great deal of soil antagonistic actinomyces in the study area. Among the 141 actinomycete strains isolated, 116 strains (82.3%) showed antagonism toward 12 target bacteria or fungi. The antagonistic strains at altitudes 800-1845, 3488, 3655, and 3670 m occupied 73.7% -86.8%, 81.3%, 78.9% and 82.3% of the total, respectively. 42.1% of the strains at altitudes 1200-2300 m and > 3400 m showed strong and broad spectrum antagonistic activity, suggesting that there was a great potential for the isolation of actinomycete strains with strong anti-biotic capability at these altitudes. 24.1% of the antagonistic actinomycetes showed antagonism against Staphyloccocus aureu, and 2.4%, 6.9% and 11.2% of them showed activity toward Verticillium dahliae in cotton, Phytophthora sp. in strawberry and Neonectria radiciccla in ginseng, respectively. This study showed that the soil actinomycete antagonistic potentiality (SAAP) could be used as a quantitative indicator to evaluate the potential of antagonistic actinomycete resources in soil. PMID:22303680

  2. Actinomycetes from the South China Sea sponges: isolation, diversity, and potential for aromatic polyketides discovery

    PubMed Central

    Sun, Wei; Zhang, Fengli; He, Liming; Karthik, Loganathan; Li, Zhiyong

    2015-01-01

    Marine sponges often harbor dense and diverse microbial communities including actinobacteria. To date no comprehensive investigation has been performed on the culturable diversity of the actinomycetes associated with South China Sea sponges. Structurally novel aromatic polyketides were recently discovered from marine sponge-derived Streptomyces and Saccharopolyspora strains, suggesting that sponge-associated actinomycetes can serve as a new source of aromatic polyketides. In this study, a total of 77 actinomycete strains were isolated from 15 South China Sea sponge species. Phylogenetic characterization of the isolates based on 16S rRNA gene sequencing supported their assignment to 12 families and 20 genera, among which three rare genera (Marihabitans, Polymorphospora, and Streptomonospora) were isolated from marine sponges for the first time. Subsequently, β-ketoacyl synthase (KSα) gene was used as marker for evaluating the potential of the actinomycete strains to produce aromatic polyketides. As a result, KSα gene was detected in 35 isolates related to seven genera (Kocuria, Micromonospora, Nocardia, Nocardiopsis, Saccharopolyspora, Salinispora, and Streptomyces). Finally, 10 strains were selected for small-scale fermentation, and one angucycline compound was detected from the culture extract of Streptomyces anulatus strain S71. This study advanced our knowledge of the sponge-associated actinomycetes regarding their diversity and potential in producing aromatic polyketides. PMID:26483773

  3. Pseudonocardia antimicrobica sp. nov., a novel endophytic actinomycete associated with Artemisia annua L. (sweet wormwood).

    PubMed

    Zhao, Guo-Zhen; Li, Jie; Qin, Yu-Li; Miao, Cui-Ping; Wei, Da-Qiao; Zhang, Si; Xu, Li-Hua; Li, Wen-Jun

    2012-09-01

    A Gram-reaction-positive, non-motile, endophytic actinomycete, designated strain YIM 63235(T), was isolated from the surface-sterilized stems of Artemisia annua L., and characterized to determine its taxonomic position. The strain YIM 63235(T) formed well-differentiated aerial and substrate mycelia on media tested. The phylogenetic tree based on 16S rRNA gene sequences showed that the new isolate formed a distinct lineage within the genus Pseudonocardia, and the strain YIM 63235(T) was closely related to Pseudonocardia parietis 04-St-002(T) (99.1%). However, DNA-DNA relatedness demonstrated that strain YIM 63235(T) was distinct from the closest phylogenetic neighbor. The chemotaxonomic properties of strain YIM 63235(T) were consistent with those of the genus Pseudonocardia: the diagnostic diamino acid of the cell-wall peptidoglycan was meso-diaminopimelic acid and MK-8(H(4)) was the predominant menaquinone. The major fatty acids were iso-C(16:0) and iso-C(16:1) H. The DNA G+C content of strain YIM 63235(T) was 71.0 mol%. On the basis of the phenotypic and phylogenetic distinctiveness, the novel isolate was identified as representing a novel species of the genus Pseudonocardia, for which the name Pseudonocardia antimicrobica sp. nov. (type strain YIM 63235(T) =CCTCC AA 208080(T)=DSM 45303(T)) is proposed. PMID:22805759

  4. Design of a strain-gage probe

    NASA Technical Reports Server (NTRS)

    Kolba, V. M.; Vetter, D. L.

    1969-01-01

    Strain-gage spacer probe uses the deflection of a leaf spring to measure strain in a long, slender beam nondestructively. The selected gage is of the smallest practical size, as thin as possible and yet of a standard type.

  5. Isolation and characterization of actinomycete antagonists of a fungal root pathogen.

    PubMed

    Crawford, D L; Lynch, J M; Whipps, J M; Ousley, M A

    1993-11-01

    By use of selective media, 267 actinomycete strains were isolated from four rhizosphere-associated and four non-rhizosphere-associated British soils. Organic media with low nutrient concentrations were found to be best for isolating diverse actinomycetes while avoiding contamination and overgrowth of isolation media by eubacteria and fungi. While all isolates grew well at pHs 6.5 to 8.0, a few were unable to grow at pH 6.0 and a significant number failed to grow at pH 5.5. Eighty-two selected isolates were screened for in vitro antagonism towards Pythium ultimum by use of a Difco cornmeal agar assay procedure. Five isolates were very strong antagonists of the fungus, four were strong antagonists, and ten others were weakly antagonistic. The remaining isolates showed no antagonism by this assay. Additional studies showed that several of the P. ultimum antagonists also strongly inhibited growth of other root-pathogenic fungi. Twelve isolates showing antifungal activity in the in vitro assay were also tested for their effects on the germination and short-term growth of lettuce plants in glasshouse pot studies in the absence of pathogens. None of the actinomycetes prevented seed germination, although half of the isolates retarded seed germination and outgrowth of the plants by 1 to 3 days. During 18-day growth experiments, biomass yields of some actinomycete-inoculated plants were reduced in comparison with untreated control plants, although all plants appeared healthy and well rooted. None of the actinomycetes significantly enhanced plant growth over these short-term experiments. For some, but not all, actinomycetes, some correlations between delayed seed germination and reduced 18-day plant biomass yields were seen. For others, plant biomass yields were not reduced despite an actinomycete-associated delay in seed germination and plant outgrowth. Preliminary glasshouse experiments indicated that some of the actinomycetes protect germinating lettuce seeds against

  6. Isolation and Characterization of Actinomycete Antagonists of a Fungal Root Pathogen †

    PubMed Central

    Crawford, Don L.; Lynch, James M.; Whipps, John M.; Ousley, Margaret A.

    1993-01-01

    By use of selective media, 267 actinomycete strains were isolated from four rhizosphere-associated and four non-rhizosphere-associated British soils. Organic media with low nutrient concentrations were found to be best for isolating diverse actinomycetes while avoiding contamination and overgrowth of isolation media by eubacteria and fungi. While all isolates grew well at pHs 6.5 to 8.0, a few were unable to grow at pH 6.0 and a significant number failed to grow at pH 5.5. Eighty-two selected isolates were screened for in vitro antagonism towards Pythium ultimum by use of a Difco cornmeal agar assay procedure. Five isolates were very strong antagonists of the fungus, four were strong antagonists, and ten others were weakly antagonistic. The remaining isolates showed no antagonism by this assay. Additional studies showed that several of the P. ultimum antagonists also strongly inhibited growth of other root-pathogenic fungi. Twelve isolates showing antifungal activity in the in vitro assay were also tested for their effects on the germination and short-term growth of lettuce plants in glasshouse pot studies in the absence of pathogens. None of the actinomycetes prevented seed germination, although half of the isolates retarded seed germination and outgrowth of the plants by 1 to 3 days. During 18-day growth experiments, biomass yields of some actinomycete-inoculated plants were reduced in comparison with untreated control plants, although all plants appeared healthy and well rooted. None of the actinomycetes significantly enhanced plant growth over these short-term experiments. For some, but not all, actinomycetes, some correlations between delayed seed germination and reduced 18-day plant biomass yields were seen. For others, plant biomass yields were not reduced despite an actinomycete-associated delay in seed germination and plant outgrowth. Preliminary glasshouse experiments indicated that some of the actinomycetes protect germinating lettuce seeds against

  7. Molecular, chemical and biological screening of soil actinomycete isolates in seeking bioactive peptide metabolites

    PubMed Central

    Imanparast, Somaye; Mohammadipanah, Fatemeh

    2015-01-01

    Background and Objective: Due to the evolution of multidrug-resistant strains, screening of natural resources, especially actinomycetes, for new therapeutic agents discovery has become the interests of researchers. In this study, molecular, chemical and biological screening of soil actinomycetes was carried out in order to search for peptide-producing actinomycetes. Materials and Methods: 60 actinomycetes were isolated from soils of Iran. The isolates were subjected to molecular screening for detection NRPS (non-ribosomal peptide synthetases) gene. Phylogenic identification of NRPS containing isolates was performed. Chemical screening of the crude extracts was performed using chlorine o-dianisidine as peptide detector reagent and bioactivity of peptide producing strains was determined by antimicrobial bioassay. High pressure liquid chromatography- mass spectrometry (HPLC-MS) with UV-visible spectroscopy was performed for detection of the metabolite diversity in selected strain. Results: Amplified NRPS adenylation gene (700 bp) was detected among 30 strains. Phylogenic identification of these isolates showed presence of rare actinomycetes genera among the isolates and 10 out of 30 strains were subjected to chemical screening. Nocardia sp. UTMC 751 showed antimicrobial activity against bacterial and fungal test pathogens. HPLC-MS and UV-visible spectroscopy results from the crude extract showed that this strain has probably the ability to produce new metabolites. Conclusion: By application of a combined approach, including molecular, chemical and bioactivity analysis, a promising strain of Nocardia sp. UTMC 751 was obtained. This strain had significant activity against Staphylococcus aureus and Pseudomonas aeruginosa. Strain Nocardia sp. UTMC 751 produce five unknown and most probably new metabolites with molecular weights of 274.2, 390.3, 415.3, 598.4 and 772.5. This strain had showed 99% similarity to Nocardia ignorata DSM 44496 T. PMID:26644870

  8. Biosurfactant produced from Actinomycetes nocardiopsis A17: Characterization and its biological evaluation.

    PubMed

    Chakraborty, Samrat; Ghosh, Mandakini; Chakraborti, Srijita; Jana, Sougata; Sen, Kalyan Kumar; Kokare, Chandrakant; Zhang, Lixin

    2015-08-01

    This investigation aims to isolate an Actinomycetes strain producing a biosurfactant from the unexplored region of industrial and coal mine areas. Actinomycetes are selected for this study as their novel chemistry was not exhausted and they have tremendous potential to produce bioactive secondary metabolites. The biosurfactant was characterized and further needed to be utilized for pharmaceutical dosage form. Isolation, purification, screening, and characterization of the Actinomycetes A17 were done followed by its fermentation in optimized conditions. The cell-free supernatant was used for the extraction of the biosurfactant and precipitated by cold acetone. The dried precipitate was purified by TLC and the emulsification index, surface tension and CMC were determined. The isolated strain with preferred results was identified as Actinomycetes nocardiopsis A17 with high foam-forming properties. It gives lipase, amylase, gelatinase, and protease activity. The emulsification index was found to be 93±0.8 with surface tension 66.67 dyne/cm at the lowest concentration and cmc 0.6 μg/ml. These biosurfactants were characterized by Fourier transform infra red (FT-IR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS). Therefore, it can be concluded that the biosurfactant produced by Actinomycetes nocardiopsis sp. strain A17 was found to have satisfactory results with high surface activity and emulsion-forming ability. PMID:25989147

  9. Actinomadura gamaensis sp. nov., a novel actinomycete isolated from soil in Gama, Chad.

    PubMed

    Abagana, Adam Yacoub; Sun, Pengyu; Liu, Chongxi; Cao, Tingting; Zheng, Weiwei; Zhao, Shanshan; Xiang, Wensheng; Wang, Xiangjing

    2016-06-01

    A novel single spore-producing actinomycete, designated strain NEAU-Gz5(T), was isolated from a soil sample from Gama, Chad. A polyphasic taxonomic study was carried out to establish the status of this strain. The diamino acid present in the cell wall is meso-diaminopimelic acid. Glucose, mannose and madurose occur in whole cell hydrolysates. The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside and an unidentified glycolipid. The predominant menaquinones were identified as MK-9(H8) and MK-9(H6). The predominant cellular fatty acids were found to be C16:0, iso-C15:0, iso-C16:0 and C18:0 10-methyl. Phylogenetic analysis based on the 16S rRNA gene showed that strain NEAU-Gz5(T) belongs to the genus Actinomadura and is closely related to Actinomadura oligospora JCM 10648(T) (ATCC 43269(T); 98.3 % similarity). However, the low level of DNA-DNA relatedness and some different phenotypic characteristics allowed the strain to be distinguished from its close relatives. Therefore, it is concluded that strain NEAU-Gz5(T) represents a novel species of the genus of Actinomadura, for which the name Actinomadura gamaensis sp. nov. is proposed. The type strain is NEAU-Gz5(T) (= CGMCC 4.7301(T) = DSM 100815(T)). PMID:27010208

  10. Phycicoccus badiiscoriae sp. nov., a novel actinomycete isolated from scoria.

    PubMed

    Lee, Soon Dong

    2013-03-01

    An actinomycete strain, designated Sco-B23(T), was isolated from a brown-coloured layer of scoria collected near Darangshi Oreum (a small mountain) in Jeju, Republic of Korea. Cells of the organism were Gram-positive, non-endospore-forming, non-motile cocci and grew at 20-35 °C, at pH 5.1-11.1 and with 0-1 % (w/v) NaCl. Colonies were circular, translucent and moderate yellow in colour with entire margins. On the basis of 16S rRNA gene sequence analysis, the isolate belonged to the genus Phycicoccus and formed a monophyletic line between a Phycicoccus bigeumensis-Phycicoccus dokdonensis cluster and a Phycicoccus aerophilus-Phycicoccus ginsenosidimutans cluster. Levels of 16S rRNA gene sequence similarity between strain Sco-B23(T) and the type strains of Phycicoccus species were: P. bigeumensis (98.8 %), P. dokdonensis (98.7 %), P. aerophilus (97.7 %), P. ginsenosidimutans (97.7 %), P. cremeus (96.9 %) and P. jejuensis (96.5 %). Chemotaxonomic analyses showed that the isolate possessed meso-diaminopimelic acid as the diamino acid of the peptidoglycan, MK-8(H4) as the predominant menaquinone, a polar lipid profile including diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unknown phospholipid and two unknown lipids, predominant fatty acids represented by iso-C15 : 0, C17 : 1cis9, iso-C16 : 0 and iso-C14 : 0, and DNA G+C content of 69.7 mol%. DNA-DNA relatedness between strain Sco-B23(T) and the close relatives within the genus Phycicoccus was below 18.1 %. On the basis of phenotypic features and DNA-DNA hybridization data, strain Sco-B23(T) represents a novel species of the genus Phycicoccus, for which the name Phycicoccus badiiscoriae sp. nov. is proposed. The type strain is Sco-B23(T) ( = KCTC 19807(T)  = KACC 15111(T)  = NBRC 107918(T)). PMID:22685104

  11. Glycomyces fuscus sp. nov. and Glycomyces albus sp. nov., actinomycetes isolated from a hypersaline habitat.

    PubMed

    Han, Xiao-Xue; Luo, Xiao-Xia; Zhang, Li-Li

    2014-07-01

    Two actinomycete strains, designated TRM 49117(T) and TRM 49136(T), were isolated from a hypersaline habitat in Xinjiang Province, north-west China and were characterized taxonomically by using a polyphasic study. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain TRM 49117(T) had 93.93% similarity with the type strain Glycomyces halotolerans TRM 40137(T) (GenBank accession no. HQ651156) and TRM 49136(T) had 94.32% similarity with G. halotolerans TRM 40137(T). The 16S rRNA gene sequence similarity between the two new isolates was 93%. The isolates contained meso-diaminopimelic acid as the diagnostic diamino acid and anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0 as major cellular fatty acids. The predominant menaquinones of the isolates were MK-9(H4) and MK-9(H6). The whole-cell sugar patterns of these strains contained xylose and ribose, and strain TRM 49136(T) also contained arabinose. The polar lipid pattern of strain TRM 49117(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylcholine, phosphatidylinositol and three additional unknown phospholipids. The polar lipid pattern of strain TRM 49136(T) comprised phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, glycolipids and two phosphoglycolipids of unknown composition. Genotypic and phenotypic data confirmed that strains TRM 49117(T) and TRM 49136(T) represent two novel species, clearly different from related species of the genus Glycomyces, for which the names Glycomyces fuscus sp. nov. (type strain TRM 49117(T) = CCTCC AA 2013003(T) = NRRL B-59998(T) = KACC 17682(T)) and Glycomyces albus sp. nov. (type strain TRM 49136(T) = CCTCC AA 2013004(T) = NRRL B-24927(T) = KACC 17681(T)) are proposed. PMID:24776532

  12. Micromonospora polyrhachis sp. nov., an actinomycete isolated from edible Chinese black ant (Polyrhachis vicina Roger).

    PubMed

    Xiang, Wensheng; Yu, Chao; Liu, Chongxi; Zhao, Junwei; Yang, Lingyu; Xie, Binjiao; Li, Lei; Hong, Kui; Wang, Xiangjing

    2014-02-01

    A novel actinomycete, designated strain NEAU-ycm2(T), was isolated from edible Chinese black ants (Polyrhachis vicina Roger) and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of the genus Micromonospora. The 16S rRNA gene sequence of strain NEAU-ycm2(T) showed highest similarity to those of Micromonospora sonneratiae 274745(T) (99.12%), Micromonospora pattaloongensis TJ2-2(T) (98.85%), Micromonospora pisi GUI 15(T) (98.76%), Polymorphospora rubra TT 97-42(T) (98.42%) and Micromonospora eburnea LK2-10(T) (98.21%). Phylogenetic analysis based on the 16S rRNA gene and gyrB gene demonstrated that strain NEAU-ycm2(T) is a member of the genus Micromonospora and supported the close phylogenetic relationship to M. sonneratiae 274745(T), M. pattaloongensis JCM 12833(T) and M. pisi GUI 15(T). Furthermore, a combination of DNA-DNA hybridization and some physiological and biochemical properties indicated that the novel strain could be readily distinguished from its closest phylogenetic relatives. Therefore, it is proposed that NEAU-ycm2(T) represents a novel species of the genus of Micromonospora, for which the name Micromonospora polyrhachis sp. nov. is proposed. The type strain is NEAU-ycm2(T) ( = CGMCC 4.7100(T) = DSM 45886(T)). PMID:24108323

  13. Antibacterial Activity of Pseudonocardia sp. JB05, a Rare Salty Soil Actinomycete against Staphylococcus aureus

    PubMed Central

    Jafari, Nesa; Behroozi, Reza; Farajzadeh, Davoud; Farsi, Mohammad; Akbari-Noghabi, Kambiz

    2014-01-01

    Staphylococcus aureus is a Gram-positive bacterium that causes many harmful and life-threatening diseases. Some strains of this bacterium are resistant to available antibiotics. This study was designed to evaluate the ability of indigenous actinomycetes to produce antibacterial compounds against S. aureus and characterize the structure of the resultant antibacterial compounds. Therefore, a slightly modified agar well diffusion method was used to determine the antibacterial activity of actinomycete isolates against the test microorganisms. The bacterial extracts with antibacterial activity were fractionated by silica gel and G-25 sephadex column chromatography. Also, the active fractions were analyzed by thin layer chromatography. Finally, the partial structure of the resultant antibacterial compound was characterized by Fourier transform infrared spectroscopy. One of the isolates, which had a broad spectrum and high antibacterial activity, was designated as Pseudonocardia sp. JB05, based on the results of biochemical and 16S rDNA gene sequence analysis. Minimum inhibitory concentration for this bacterium was 40 AU mL−1 against S. aureus. The antibacterial activity of this bacterium was stable after autoclaving, 10% SDS, boiling, and proteinase K. Thin layer chromatography, using anthrone reagent, showed the presence of carbohydrates in the purified antibacterial compound. Finally, FT-IR spectrum of the active compound illustrated hydroxyl groups, hydrocarbon skeleton, and double bond of polygenic compounds in its structure. To the best of our knowledge, this is the first report describing the efficient antibacterial activity by a local strain of Pseudonocardia. The results presented in this work, although at the initial stage in bioactive product characterization, will possibly contribute toward the Pseudonocardia scale-up for the production and identification of the antibacterial compounds. PMID:25202705

  14. Isolation, taxonomy, and antagonistic properties of halophilic actinomycetes in Saharan soils of Algeria.

    PubMed

    Meklat, Atika; Sabaou, Nasserdine; Zitouni, Abdelghani; Mathieu, Florence; Lebrihi, Ahmed

    2011-09-01

    The diversity of a population of 52 halophilic actinomycetes was evaluated by a polyphasic approach, which showed the presence of members of the Actinopolyspora, Nocardiopsis, Saccharomonospora, Streptomonospora, and Saccharopolyspora genera. One strain was considered to be a new member of the last genus, and several other strains seemed to be new species. Furthermore, 50% of strains were active against a broad range of indicators and contained genes encoding polyketide synthetases and nonribosomal peptide synthetases. PMID:21764956

  15. Isolation, Taxonomy, and Antagonistic Properties of Halophilic Actinomycetes in Saharan Soils of Algeria ▿

    PubMed Central

    Meklat, Atika; Sabaou, Nasserdine; Zitouni, Abdelghani; Mathieu, Florence; Lebrihi, Ahmed

    2011-01-01

    The diversity of a population of 52 halophilic actinomycetes was evaluated by a polyphasic approach, which showed the presence of members of the Actinopolyspora, Nocardiopsis, Saccharomonospora, Streptomonospora, and Saccharopolyspora genera. One strain was considered to be a new member of the last genus, and several other strains seemed to be new species. Furthermore, 50% of strains were active against a broad range of indicators and contained genes encoding polyketide synthetases and nonribosomal peptide synthetases. PMID:21764956

  16. Streptomyces bryophytorum sp. nov., an endophytic actinomycete isolated from moss (Bryophyta).

    PubMed

    Li, Chuang; Jin, Pinjiao; Liu, Chongxi; Ma, Zhaoxu; Zhao, Junwei; Li, Jiansong; Wang, Xiangjing; Xiang, Wensheng

    2016-09-01

    A novel endophytic actinomycete, designated strain NEAU-HZ10(T) was isolated from moss and characterised using a polyphasic approach. The strain was found to have morphological and chemotaxonomic characteristics typical of the genus Streptomyces. Strain NEAU-HZ10(T) formed grayish aerial mycelia, which differentiated into straight to flexuous chains of cylindrical spores. The cell wall peptidoglycan was found to contain LL-diaminopimelic acid. Predominant menaquinones were identified as MK-9(H6) and MK-9(H8). The polar lipid profile was found to consist of phosphatidylethanolamine, phosphatidylinositol and two unidentified phospholipids. The major fatty acids were identified as iso-C16:0, anteiso-C15:0 and C16:0. 16S rRNA gene sequence similarity studies showed that strain NEAU-HZ10(T) belongs to the genus Streptomyces and exhibits high sequence similarity to Streptomyces cocklensis DSM 42063(T) (98.9 %). Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain NEAU-HZ10(T) clustered with S. cocklensis DSM 42063(T), Streptomyces yeochonensis CGMCC 4.1882(T) (98.7 %), Streptomyces paucisporeus CGMCC 4.2025(T) (98.4 %) and Streptomyces yanglinensis CGMCC 4.2023(T) (98.1 %). However, a combination of DNA-DNA hybridisation results and some phenotypic characteristics indicated that strain NEAU-HZ10(T) can be distinguished from its phylogenetically closely related strains. Therefore, it is proposed that strain NEAU-HZ10(T) represents a novel species of the genus Streptomyces for which the name Streptomyces bryophytorum sp. nov. is proposed. The type strain is NEAU-HZ10(T) (= CGMCC 4.7151(T) = DSM 42138(T)). PMID:27263023

  17. Streptomyces formicae sp. nov., a novel actinomycete isolated from the head of Camponotus japonicus Mayr.

    PubMed

    Bai, Lu; Liu, Chongxi; Guo, Lifeng; Piao, Chenyu; Li, Zhilei; Li, Jiansong; Jia, Feiyu; Wang, Xiangjing; Xiang, Wensheng

    2016-02-01

    During a screening for novel and biotechnologically useful actinobacteria in insects, a novel actinomycete with antifungal activity, designated strain 1H-GS9(T), was isolated from the head of a Camponotus japonicus Mayr ant, which were collected from Northeast Agricultural University (Harbin, Heilongjiang, China). Strain 1H-GS9(T) was characterised using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of members of the genus Streptomyces. 16S rRNA gene sequence similarity studies showed that strain 1H-GS9(T) belongs to the genus Streptomyces with high sequence similarities to Streptomyces scopuliridis DSM 41917(T) (98.8 %) and Streptomyces mauvecolor JCM 5002(T) (98.6 %). However, phylogenetic analysis based on the 16S rRNA gene sequence indicated that it forms a monophyletic clade with Streptomyces kurssanovii JCM 4388(T) (98.6 %), Streptomyces xantholiticus JCM 4282(T) (98.6 %) and Streptomyces peucetius JCM 9920(T) (98.5 %). Thus, a combination of DNA-DNA hybridization experiments and phenotypic tests were carried out between strain 1H-GS9(T) and the above-mentioned five strains, which further clarified their relatedness and demonstrated that strain 1H-GS9(T) could be distinguished from these strains. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces formicae sp. nov. is proposed. The type strain is 1H-GS9(T) (=CGMCC 4.7277(T) = DSM 100524(T)). PMID:26608172

  18. Streptomonospora algeriensis sp. nov., a halophilic actinomycete isolated from soil in Algeria.

    PubMed

    Meklat, Atika; Bouras, Noureddine; Riba, Amar; Zitouni, Abdelghani; Mathieu, Florence; Rohde, Manfred; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter; Sabaou, Nasserdine

    2014-08-01

    A halophilic actinomycete strain, designated H27(T), was isolated from a soil sample collected from a hypersaline habitat in Djelfa Province (North-Central Algeria), and then investigated using a polyphasic taxonomic approach. The strain was observed to produce poor aerial mycelium, which formed short chains of oval to cylindrical-shaped spores at maturity, and non fragmented substrate mycelium. The optimum NaCl concentration for growth was found to be 10-15 % (w/v) and the optimum growth temperature and pH were found to be 28-37 °C and 6-7, respectively. The diagnostic diamino acid in the cell-wall peptidoglycan was identified as meso-diaminopimelic acid. The predominant menaquinones of strain H27(T) were identified as MK-11 (H4) and MK-10 (H6). The major fatty acids were found to be iso-C16:0, anteiso-C17:0, 10 methyl C17:0 and 10 methyl C16:0. The diagnostic phospholipids detected were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and phosphatidylinositol. The chemotaxonomic properties of strain H27(T) are consistent with those shared by members of the genus Streptomonospora. 16S rRNA gene sequence analysis indicated that strain H27(T) is most closely related to Streptomonospora alba DSM 44588(T) (98.8 %) and Streptomonospora flavalba DSM 45155(T) (98.7 %) whereas the DNA-DNA relatedness values between strain H27(T) and the two type strains were 17.1 and 57.9 %, respectively. Based on the combined genotypic and phenotypic evidence, it is proposed that strain H27(T) should be classified as representative of a novel species, for which the name Streptomonospora algeriensis sp. nov. is proposed. The type strain is H27(T) (=DSM 45604(T) =CCUG 63369(T) =MTCC 11563(T)). PMID:24858572

  19. Draft Genome Sequence of Planomonospora sphaerica JCM9374, a Rare Actinomycete

    PubMed Central

    Dohra, Hideo; Suzuki, Tomohiro; Inoue, Yuto

    2016-01-01

    Planomonospora sphaerica is a rare actinomycete that is a potential antibiotic producer. Here, we report the draft genome sequence of P. sphaerica strain JCM9374. This is the first genome report of a bacterium belonging to the genus Planomonospora. The genome information of P. sphaerica will contribute to studies on the structure and function of antibiotics. PMID:27492001

  20. Draft Genome Sequence of Planomonospora sphaerica JCM9374, a Rare Actinomycete.

    PubMed

    Dohra, Hideo; Suzuki, Tomohiro; Inoue, Yuto; Kodani, Shinya

    2016-01-01

    Planomonospora sphaerica is a rare actinomycete that is a potential antibiotic producer. Here, we report the draft genome sequence of P. sphaerica strain JCM9374. This is the first genome report of a bacterium belonging to the genus Planomonospora The genome information of P. sphaerica will contribute to studies on the structure and function of antibiotics. PMID:27492001

  1. Combination of uniform design with artificial neural network coupling genetic algorithm: an effective way to obtain high yield of biomass and algicidal compound of a novel HABs control actinomycete

    PubMed Central

    2014-01-01

    Controlling harmful algae blooms (HABs) using microbial algicides is cheap, efficient and environmental-friendly. However, obtaining high yield of algicidal microbes to meet the need of field test is still a big challenge since qualitative and quantitative analysis of algicidal compounds is difficult. In this study, we developed a protocol to increase the yield of both biomass and algicidal compound present in a novel algicidal actinomycete Streptomyces alboflavus RPS, which kills Phaeocystis globosa. To overcome the problem in algicidal compound quantification, we chose algicidal ratio as the index and used artificial neural network to fit the data, which was appropriate for this nonlinear situation. In this protocol, we firstly determined five main influencing factors through single factor experiments and generated the multifactorial experimental groups with a U15(155) uniform-design-table. Then, we used the traditional quadratic polynomial stepwise regression model and an accurate, fully optimized BP-neural network to simulate the fermentation. Optimized with genetic algorithm and verified using experiments, we successfully increased the algicidal ratio of the fermentation broth by 16.90% and the dry mycelial weight by 69.27%. These results suggested that this newly developed approach is a viable and easy way to optimize the fermentation conditions for algicidal microorganisms. PMID:24886410

  2. Antitumor Compounds from Marine Actinomycetes

    PubMed Central

    Olano, Carlos; Méndez, Carmen; Salas, José A.

    2009-01-01

    Chemotherapy is one of the main treatments used to combat cancer. A great number of antitumor compounds are natural products or their derivatives, mainly produced by microorganisms. In particular, actinomycetes are the producers of a large number of natural products with different biological activities, including antitumor properties. These antitumor compounds belong to several structural classes such as anthracyclines, enediynes, indolocarbazoles, isoprenoides, macrolides, non-ribosomal peptides and others, and they exert antitumor activity by inducing apoptosis through DNA cleavage mediated by topoisomerase I or II inhibition, mitochondria permeabilization, inhibition of key enzymes involved in signal transduction like proteases, or cellular metabolism and in some cases by inhibiting tumor-induced angiogenesis. Marine organisms have attracted special attention in the last years for their ability to produce interesting pharmacological lead compounds. PMID:19597582

  3. Actinomycetes for Marine Drug Discovery Isolated from Mangrove Soils and Plants in China

    PubMed Central

    Hong, Kui; Gao, An-Hui; Xie, Qing-Yi; Gao, Hao; Zhuang, Ling; Lin, Hai-Peng; Yu, Hai-Ping; Li, Jia; Yao, Xin-Sheng; Goodfellow, Michael; Ruan, Ji-Sheng

    2009-01-01

    The mangrove ecosystem is a largely unexplored source for actinomycetes with the potential to produce biologically active secondary metabolites. Consequently, we set out to isolate, characterize and screen actinomycetes from soil and plant material collected from eight mangrove sites in China. Over 2,000 actinomycetes were isolated and of these approximately 20%, 5%, and 10% inhibited the growth of Human Colon Tumor 116 cells, Candida albicans and Staphylococcus aureus, respectively, while 3% inhibited protein tyrosine phosphatase 1B (PTP1B), a protein related to diabetes. In addition, nine isolates inhibited aurora kinase A, an anti-cancer related protein, and three inhibited caspase 3, a protein related to neurodegenerative diseases. Representative bioactive isolates were characterized using genotypic and phenotypic procedures and classified to thirteen genera, notably to the genera Micromonospora and Streptomyces. Actinomycetes showing cytotoxic activity were assigned to seven genera whereas only Micromonospora and Streptomyces strains showed anti-PTP1B activity. We conclude that actinomycetes isolated from mangrove habitats are a potentially rich source for the discovery of anti-infection and anti-tumor compounds, and of agents for treating neurodegenerative diseases and diabetes. PMID:19370169

  4. Actinorugispora endophytica gen. nov., sp. nov., an actinomycete isolated from Daucus carota.

    PubMed

    Liu, Min-Jiao; Zhu, Wen-Yong; Li, Jie; Zhao, Guo-Zhen; Xiong, Zhi; Park, Dong-Jin; Hozzein, Wael N; Kim, Chang-Jin; Li, Wen-Jun

    2015-08-01

    An actinomycete strain, designated YIM 690008T, was isolated from Daucus carota collected from South Korea and its taxonomic position was investigated by using a polyphasic approach. The strain grew well on most media tested and no diffusible pigment was produced. The aerial mycelium formed wrinkled single spores and short spore chains, some of which were branched. The whole-cell hydrolysates contained meso-diaminopimelic acid, glucose, mannose, ribose, galactose and rhamnose. The predominant menaquinones were MK-10(H4), MK-10(H6), MK-10(H8) and MK-10(H2). The polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannosides, some unknown phospholipids, glycolipids and polar lipids. The major fatty acids were i-C16 : 0, ai-C17 : 0 and C18 : 1ω9c. The DNA G+C content of the genomic DNA was 63.1 mol%. Phylogenetic analysis indicated that the isolate belongs to the family Nocardiopsaceae. However, based on phenotypic, chemotaxonomic and genotypic data, it was concluded that strain YIM 690008T represents a novel genus and novel species of the family Nocardiopsaceae, for which the name Actinorugispora endophytica gen. nov., sp. nov. (type strain YIM 690008T = DSM 46770T = JCM 30099T = KCTC 29480T) is proposed. PMID:25948617

  5. Designing recombinant Pseudomonas strains to enhance biodesulfurization.

    PubMed Central

    Gallardo, M E; Ferrández, A; De Lorenzo, V; García, J L; Díaz, E

    1997-01-01

    The dsz biodesulfurization cluster from Rhodococcus erythropolis IGTS8 has been engineered under the control of heterologous broad-host-range regulatory signals to alleviate the mechanism of sulfur repression, and it was stably inserted into the chromosomes of different Pseudomonas strains. The recombinant bacteria were able to desulfurize dibenzothiophene more efficiently than the native host. Furthermore, these new biocatalysts combine relevant industrial and environmental traits, such as production of biosurfactants, with the enhanced biodesulfurization phenotype. PMID:9371464

  6. Nonomuraea indica sp. nov., novel actinomycetes isolated from lime-stone open pit mine, India.

    PubMed

    Quadri, Syed Raziuddin; Tian, Xin-Peng; Zhang, Jing; Li, Jie; Nie, Guo-Xing; Tang, Shu-Kun; Al Ruwaili, Jamal; Agsar, Dayanand; Li, Wen-Jun; Dastager, Syed G

    2015-08-01

    A Gram-positive, aerobic, nonmotile actinomycete strain designated DRQ-2(T) was isolated from the soil sample collected from lime-stone open pit mine from the Gulbarga region, Karnataka province, India. Strain DRQ-2(T) was identified as a member of the genus Nonomuraea by a polyphasic approach. Strain DRQ-2(T) could be differentiated from other members of the genus Nonomuraea on the basis of physiology and 16S rRNA gene sequence analysis. The 16S rRNA gene sequence similarity of strain DRQ-2(T) showed highest sequence similarity to Nonomuraea muscovyensis DSM 45913(T) (99.1%), N. salmonea DSM 43678(T) (98.2%) and N. maheshkhaliensis JCM 13929(T) with 98.0%, respectively. Chemotaxonomic properties showing predominant menaquinones of MK-9 (H4), MK-9(H2) and MK-9(H6), major polar lipids comprised diphosphatidylglycerol, phosphatidylmono methyl ethanolamine (PME), phosphatidylethanolamine (PE), hydroxy-PME (OH-PME), hydroxy PE (OH-PEE), phosphatidylglycerol (PG), ninhydrin-positive phosphoglycolipid and unknown phospholipid, fatty acids with major amounts of i-C16:0, ai-C15:0 and ai-C17:0 supported allocation of the strain to the genus Nonomuraea. Results of DNA-DNA hybridization and physiological tests allowed genotypic and phenotypic differentiation of strain DRQ-2(T) from closely related species. The genomic DNA G+C content of the organism was 72.5 mol%. On the basis of phenotypic, chemotypic and molecular characteristics, strain DRQ-2(T) represents a novel species of the genus Nonomuraea, for which the name N. indica sp. nov. is proposed, with type strain DRQ-2(T) (=NCIM 5480(T)= CCTCC AA 209050(T)). PMID:25783226

  7. Saccharopolyspora ghardaiensis sp. nov., an extremely halophilic actinomycete isolated from Algerian Saharan soil.

    PubMed

    Meklat, Atika; Bouras, Noureddine; Zitouni, Abdelghani; Sabaou, Nasserdine; Mathieu, Florence; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter

    2014-04-01

    A novel halophilic actinomycete, strain designated H53(T), was isolated from a Saharan soil sample collected from Chaâbet Ntissa, Béni-isguen, Ghardaïa (South of Algeria) and was characterized taxonomically by means of polyphasic approach. Optimal growth was found to occur at 30-35 °C, pH 6-7 and in the presence of 15-25% (w/v) NaCl. The strain was observed to produce abundant aerial mycelium, which formed long chains of rod-shaped spores at maturity, and well developed and fragmented substrate mycelium. The cell wall was determined to contain meso-diaminopimelic acid; the diagnostic whole-cell sugars were arabinose and galactose. The predominant menaquinones were found to be MK-9(H₄) and MK-9(H₆). The predominant cellular fatty acids were determined to be iso- and anteiso-C17:0, iso-C15:0, and cis9 iso-C17:1. The diagnostic phospholipid detected was phosphatidylcholine. The morphological and chemotaxonomic characteristics of the strain were consistent with those of members of the genus Saccharopolyspora. Phylogenetic analyses on the basis of the 16S ribosomal RNA (rRNA) gene sequence showed that this strain formed a distinct phyletic line within the radiation of the genus Saccharopolyspora. The 16S rRNA sequence similarities between strain H53(T) and other members of the genus Saccharopolyspora ranged from 92.1 to 94.3%. The DNA G+C content of strain H53(T) was 72.6%. The genotypic and phenotypic data showed that the strain H53(T) represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora ghardaiensis sp. nov. is proposed, with the type strain H53(T) (=DSM 45606(T)=CCUG 63370(T)=CECT 8304(T)). PMID:24346634

  8. Actinocorallia lasiicapitis sp. nov., an actinomycete isolated from the head of an ant (Lasius fuliginosus L.).

    PubMed

    Liu, Chongxi; Li, Yao; Ye, Lan; Zhao, Junwei; Piao, Chenyu; Li, Zhilei; Li, Jiansong; Xiang, Wensheng; Wang, Xiangjing

    2016-06-01

    A novel actinomycete, designated strain 3H-GS17T, was isolated from the head of an ant (Lasius fuliginosus L.) and characterized using a polyphasic approach. 16S rRNA gene sequence similarity studies showed that strain 3H-GS17T belongs to the genus Actinocorallia with high sequence similarity to Actinocorallia glomerata JCM 9376T (98.13 %) and Actinocorallia longicatena JCM 9377T (97.64 %). The chemotaxonomic properties of strain 3H-GS17T were also consistent with those of members of the genus Actinocorallia. The cell wall contained meso-diaminopimelic acid and whole-cell sugars were ribose, mannose, glucose, galactose and madurose. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H8). The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The major fatty acids were C16 : 0 and C18 : 1ω7с. A combination of DNA-DNA hybridization experiments and phenotypic tests were carried out between strain 3H-GS17T and its closely related strains, which further clarified their relatedness and demonstrated that 3H-GS17T could be distinguished from these strains. Therefore, strain 3H-GS17T is concluded to represent a novel species of the genus Actinocorallia, for which the name Actinocorallia lasiicapitis sp. nov. is proposed. The type strain is 3H-GS17T (=DSM 100595T=CGMCC 4.7282T). PMID:26944933

  9. NASA LaRC Strain Gage Balance Design Concepts

    NASA Technical Reports Server (NTRS)

    Rhew, Ray D.

    1999-01-01

    The NASA Langley Research Center (LaRC) has been designing strain-gage balances for more than fifty years. These balances have been utilized in Langley's wind tunnels, which span over a wide variety of aerodynamic test regimes, as well as other ground based test facilities and in space flight applications. As a result, the designs encompass a large array of sizes, loads, and environmental effects. Currently Langley has more than 300 balances available for its researchers. This paper will focus on the design concepts for internal sting mounted strain-gage balances. However, these techniques can be applied to all force measurement design applications. Strain-gage balance concepts that have been developed over the years including material selection, sting, model interfaces, measuring, sections, fabrication, strain-gaging and calibration will be discussed.

  10. Streptomyces gilvifuscus sp. nov., an actinomycete that produces antibacterial compounds isolated from soil.

    PubMed

    Nguyen, uan Manh; Kim, Jaisoo

    2015-10-01

    This study describes a novel actinomycete, designated T113T, which was isolated from forest soil in Pyeongchang-gun, Republic of Korea, and is an aerobic, Gram-stain-positive actinobacterium that forms flexibilis chains of smooth, elliptical or short rod-shaped spores. The results of 16S rRNA sequence analysis indicated that strain T113T exhibited high levels of similarity to previously characterized species of the genus Streptomyces (98.19–98.89 %, respectively). However, the results of phylogenetic and DNA–DNA hybridization analyses confirmed that the organism represented a novel member of the genus Streptomyces. Furthermore, using chemotaxonomic and phenotypic analyses it was demonstrated that the strain exhibited characteristics similar to those of other members of the genus Streptomyces. The primary cellular fatty acids expressed by this strain included anteiso-C15 : 0, anteiso-C17 : 0, iso-C15 : 0 and iso-C16 : 0. While diphosphatidylglycerol and phosphatidylethanolamine were the predominant lipids expressed by strain T113T, moderate amounts of phosphatidylinositol and phosphatidylinositol mannoside were also detected. Whole-cell hydrolysates contained glucose and ribose, and the predominant menaquinone detected was MK-9 (H6); however, moderate amounts of MK-9 (H8) and trace amounts of MK-10 (H2) and MK-10 (H4) were also detected. We therefore propose that strain T113T be considered as representing a novel species of the genus Streptomyces and propose the name Streptomyces gilvifuscus sp. nov. for this species, with strain T113T ( = KEMB 9005-213T = KACC 18248T = NBRC 110904T) being the type strain. PMID:26297131

  11. ISOLATION AND DIVERSITY OF ACTINOMYCETES IN THE CHESAPEAKE BAY

    EPA Science Inventory

    Chesapeake Bay was investigated as a source of actinomycetes to creen for production of novel bioactive compounds. he presence of relatively large populations of actinoplanetes, chemotype IID actinomycetes in Chesapeake Bay sediment samples indicates that is an eminently suitable...

  12. Glycomyces tarimensis sp. nov., an actinomycete isolated from a saline-alkali habitat.

    PubMed

    Lv, Ling-Ling; Zhang, Yue-Feng; Zhang, Li-Li

    2015-05-01

    A novel actinomycete strain, designated TRM 45387(T), was isolated from a saline-alkali soil in Xinjiang Province (40° 22' N 79° 08' E), north-west China. The isolate was characterized using a polyphasic approach. 16S rRNA gene sequence analysis indicated that strain TRM 45387(T) belonged to the genus Glycomyces and was closely related to Glycomyces arizonensis DSM 44726(T) (96.59% 16S rRNA gene sequence similarity). The G+C content of the DNA was 71.26 mol%. The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid, and xylose, glucose, galactose, arabinose and ribose as the major whole-cell sugars. The diagnostic phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositolmannosides. The predominant menaquinone was MK-10(H6). The major fatty acids were iso-C16 : 0, anteiso-C17 : 0 and anteiso-C15 : 0. On the basis of the evidence from this polyphasic study, a novel species, Glycomyces tarimensis sp. nov., is proposed. The type strain of Glycomyces tarimensis is TRM 45387(T) ( =CCTCC AA 2014007(T) =JCM 30184(T)). PMID:25713037

  13. Saccharopolyspora halotolerans sp. nov., a halophilic actinomycete isolated from a hypersaline lake.

    PubMed

    Lv, Ling-Ling; Zhang, Yue-Feng; Xia, Zhan-Feng; Zhang, Jing-Jing; Zhang, Li-Li

    2014-10-01

    A novel actinomycete strain, designated TRM 45123(T), was isolated from a hypersaline habitat in Xinjiang Province (40° 20' N 90° 49' E), north-west China. The isolate was characterized using a polyphasic approach. 16S rRNA gene sequence analysis indicated that strain TRM 45123(T) belonged to the genus Saccharopolyspora and was closely related to Saccharopolyspora gloriosae (96.7% similarity). The G+C content of the DNA was 69.07 mol%. The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid, and arabinose and ribose as the major whole-cell sugars. The diagnostic phospholipids were phosphatidylethanolamine, phosphatidylcholine and phosphatidylglycerol. The predominant menaquinone was MK-9(H4). The major fatty acids were iso-C16 : 0, anteiso-C17:0, iso-C15:0 and anteiso-C15:0. On the basis of the evidence from this polyphasic study, a novel species, Saccharopolyspora halotolerans sp. nov., is proposed. The type strain of Saccharopolyspora halotolerans is TRM 45123(T) ( = CCTCC AA 2013006(T) = DSM 45990(T)). PMID:25061064

  14. Amycolatopsis salitolerans sp. nov., a filamentous actinomycete isolated from a hypersaline habitat.

    PubMed

    Guan, Tong-Wei; Xia, Zhan-Feng; Tang, Shu-Kun; Wu, Nan; Chen, Zheng-Jun; Huang, Ying; Ruan, Ji-Sheng; Li, Wen-Jun; Zhang, Li-Li

    2012-01-01

    A novel actinomycete strain, designated TRM F103(T), was isolated from a hypersaline habitat of the Tarim basin in Xinjiang province, north-west China. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the genus Amycolatopsis and was most closely related to Amycolatopsis halophila YIM 93223(T) (99.3% 16S rRNA gene sequence similarity). However, DNA-DNA relatedness between these two strains, based on triplicate experiments, was only 31.6%. The isolate contained meso-diaminopimelic acid and ribose, glucose and galactose as the major whole-cell sugars. The predominant menaquinone was MK-8(H(4)). The major fatty acids were iso-C(16:0) and C(16:0). The polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine and glucosamine-containing phospholipids. The G+C content of the genomic DNA was 66.4 mol%. The phenotypic data clearly distinguished the isolate from its closest relatives. The combined phylogenetic, chemotaxonomic and phenotypic data indicate that the isolate represents a novel species of the genus Amycolatopsis. The proposed name is Amycolatopsis salitolerans sp. nov., with TRM F103(T) (=JCM 15899(T)=CCTCC AB 208326(T)) as the type strain. PMID:21317279

  15. Biodiversity, Anti-Trypanosomal Activity Screening, and Metabolomic Profiling of Actinomycetes Isolated from Mediterranean Sponges

    PubMed Central

    Cheng, Cheng; MacIntyre, Lynsey; Abdelmohsen, Usama Ramadan; Horn, Hannes; Polymenakou, Paraskevi N.; Edrada-Ebel, RuAngelie; Hentschel, Ute

    2015-01-01

    Marine sponge–associated actinomycetes are considered as promising sources for the discovery of novel biologically active compounds. In the present study, a total of 64 actinomycetes were isolated from 12 different marine sponge species that had been collected offshore the islands of Milos and Crete, Greece, eastern Mediterranean. The isolates were affiliated to 23 genera representing 8 different suborders based on nearly full length 16S rRNA gene sequencing. Four putatively novel species belonging to genera Geodermatophilus, Microlunatus, Rhodococcus and Actinomycetospora were identified based on a 16S rRNA gene sequence similarity of < 98.5% to currently described strains. Eight actinomycete isolates showed bioactivities against Trypanosma brucei brucei TC221 with half maximal inhibitory concentration (IC50) values <20 μg/mL. Thirty four isolates from the Milos collection and 12 isolates from the Crete collection were subjected to metabolomic analysis using high resolution LC-MS and NMR for dereplication purposes. Two isolates belonging to the genera Streptomyces (SBT348) and Micromonospora (SBT687) were prioritized based on their distinct chemistry profiles as well as their anti-trypanosomal activities. These findings demonstrated the feasibility and efficacy of utilizing metabolomics tools to prioritize chemically unique strains from microorganism collections and further highlight sponges as rich source for novel and bioactive actinomycetes. PMID:26407167

  16. Biodiversity, Anti-Trypanosomal Activity Screening, and Metabolomic Profiling of Actinomycetes Isolated from Mediterranean Sponges.

    PubMed

    Cheng, Cheng; MacIntyre, Lynsey; Abdelmohsen, Usama Ramadan; Horn, Hannes; Polymenakou, Paraskevi N; Edrada-Ebel, RuAngelie; Hentschel, Ute

    2015-01-01

    Marine sponge-associated actinomycetes are considered as promising sources for the discovery of novel biologically active compounds. In the present study, a total of 64 actinomycetes were isolated from 12 different marine sponge species that had been collected offshore the islands of Milos and Crete, Greece, eastern Mediterranean. The isolates were affiliated to 23 genera representing 8 different suborders based on nearly full length 16S rRNA gene sequencing. Four putatively novel species belonging to genera Geodermatophilus, Microlunatus, Rhodococcus and Actinomycetospora were identified based on a 16S rRNA gene sequence similarity of < 98.5% to currently described strains. Eight actinomycete isolates showed bioactivities against Trypanosma brucei brucei TC221 with half maximal inhibitory concentration (IC50) values <20 μg/mL. Thirty four isolates from the Milos collection and 12 isolates from the Crete collection were subjected to metabolomic analysis using high resolution LC-MS and NMR for dereplication purposes. Two isolates belonging to the genera Streptomyces (SBT348) and Micromonospora (SBT687) were prioritized based on their distinct chemistry profiles as well as their anti-trypanosomal activities. These findings demonstrated the feasibility and efficacy of utilizing metabolomics tools to prioritize chemically unique strains from microorganism collections and further highlight sponges as rich source for novel and bioactive actinomycetes. PMID:26407167

  17. Biodiversity of Actinomycetes associated with Caribbean sponges and their potential for natural product discovery.

    PubMed

    Vicente, Jan; Stewart, Allison; Song, Bongkeun; Hill, Russell T; Wright, Jeffrey L

    2013-08-01

    Marine actinomycetes provide a rich source of structurally unique and bioactive secondary metabolites. Numerous genera of marine actinomycetes have been isolated from marine sediments as well as several sponge species. In this study, 16 different species of Caribbean sponges were collected from four different locations in the coastal waters off Puerto Rico in order to examine diversity and bioactive metabolite production of marine actinomycetes in Caribbean sponges. Sediments were also collected from each location, in order to compare actinomycete communities between these two types of samples. A total of 180 actinomycetes were isolated and identified based on 16S rRNA gene analysis. Phylogenetic analysis revealed the presence of at least 14 new phylotypes belonging to the genera Micromonospora, Verruscosispora, Streptomyces, Salinospora, Solwaraspora, Microbacterium and Cellulosimicrobium. Seventy-eight of the isolates (19 from sediments and 59 from sponges) shared 100 % sequence identity with Micromonospora sp. R1. Despite having identical 16S rRNA sequences, the bioactivity of extracts and subsequent fractions generated from the fermentation of both sponge- and sediment-derived isolates identical to Micromonospora sp. R1 varied greatly, with a marked increase in antibiotic metabolite production in those isolates derived from sponges. These results indicate that the chemical profiles of isolates with high 16S rRNA sequence homology to known strains can be diverse and dependent on the source of isolation. In addition, seven previously reported dihydroquinones produced by five different Streptomyces strains have been purified and characterized from one Streptomyces sp. strain isolated in this study from the Caribbean sponge Agelas sceptrum. PMID:23344968

  18. Production of Bioactive Compounds by Actinomycetes and Their Antioxidant Properties

    PubMed Central

    Janardhan, Avilala; Kumar, Arthala Praveen; Viswanath, Buddolla; Saigopal, D. V. R.; Narasimha, Golla

    2014-01-01

    An actinomycete was isolated from mangrove soil collected from Nellore region of Andhra Pradesh, India, and screened for its ability to produce bioactive compounds. The cultural, morphological, and biochemical characters and 16S rRNA sequencing suggest that the isolated strain is Nocardiopsis alba. The bioactive compounds produced by this strain were purified by column chromatography. The in vitro antioxidant capacity of the isolated compounds (fractions) was estimated and fraction F2 showed very near values to the standard ascorbic acid. The potential fraction obtained by column chromatography was subjected to HPLC for further purification, then this purified fraction F2 was examined by FTIR, NMR, and mass spectroscopy to elucidate its chemical structure. By spectral data, the structure of the isolated compound was predicted as “(Z)-1-((1-hydroxypenta-2,4-dien-1-yl)oxy)anthracene-9,10-dione.” PMID:24790761

  19. Antimicrobial Metabolites from a Marine-Derived Actinomycete in Vietnam's East Sea.

    PubMed

    Thi, Quyen Vu; Tran, Van Hieu; Maia, Huong Doan Thi; Le, Cong Vinh; Hong, Minh Le Thi; Murphy, Brian T; Chau, Van Minh; Pham, Van Cuong

    2016-01-01

    Two new compounds, a quinoline alkaloid (1) and a 1,4-dioxane derivative (2), were isolated from culture broth of the marine-derived actinomycete Micromonospora sp. (strain G019) by bioassay-guided fractionation. This actinomycete strain was isolated from sediment, collected at Cát Bà Peninsula, Vietnam. The taxonomic identification was achieved by analysis of 16S rRNA gene sequences. On the basis of morphological and phylogenetic evidence, strain G019 was assigned to the genus Micromonospora. The structures of 1 and 2 were established by spectroscopic data analysis, including one- and two-dimensional NMR, and MS. Compound 1 was found to have antibacterial activity against Escherichia coli (MIC: 48 µg/mL), Salmonella enterica (MIC: 96 µg/mL) and Enterococcus faecalis (MIC: 128 µg/mL), while compound 2 showed inhibitory activity against Enterococcusfaecalis (MIC: 32 µg/mL) and Candida albicans (MIC: 64 µg/mL). PMID:26996018

  20. Inhibition of norsolorinic acid accumulation to Aspergillus parasiticus by marine actinomycetes

    NASA Astrophysics Data System (ADS)

    Yan, Peisheng; Shi, Cuijuan; Shen, Jihong; Wang, Kai; Gao, Xiujun; Li, Ping

    2014-11-01

    Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and the production of norsolorinic acid using dual culture plate assay and agar diffusion methods. Among them, three strains showed strong antifungal activity and were subsequently identified as Streptomyces sp. by 16S rRNA gene sequencing analysis. The supernatant from the fermentation of the MA01 strain was extracted sequentially with chloroform and ethyl acetate, and the activities of the extracts were determined by tip culture assay. The assay results show that both extracts inhibited mycelium growth and toxin production, and the inhibitory activities of the extracts increased as their concentrations increased. The results of this study suggest that marine actinomycetes are biologically important for the control of mycotoxins, and that these bacteria could be used as novel biopesticides against mycotoxins.

  1. Streptomyces tyrosinilyticus sp. nov., a novel actinomycete isolated from river sediment.

    PubMed

    Zhao, Junwei; Guo, Lifeng; Liu, Chongxi; Bai, Lu; Han, Chuanyu; Li, Jiansong; Xiang, Wensheng; Wang, Xiangjing

    2015-09-01

    A novel actinomycete, designated strain NEAU-Jh3-20(T), was isolated from river sediment collected from South river in Jilin Province, north China and characterized using a polyphasic approach. Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain NEAU-Jh3-20(T) should be assigned to the genus Streptomyces and forms a distinct branch with its closest neighbour Streptomyces vitaminophilus DSM 41686(T)(97.09%). Moreover, key morphological and chemotaxonomic properties also confirmed the affiliation of strain NEAU-Jh3-20(T) to the genus Streptomyces. The cell wall contained ll-diaminopimelic acid and the whole-cell hydrolysates were glucose and ribose. The phospholipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides and an unidentified phospholipid. The predominant menaquinones were MK-9(H8) and MK-9(H6). The major fatty acids were C16 : 0, C18 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The DNA G+C content was 72.2 mol%. A combination of DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-Jh3-20(T) could be distinguished from its closest phylogenetic relative. Therefore, it is proposed that strain NEAU-Jh3-20(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces tyrosinilyticus sp. nov. is proposed. The type strain is NEAU-Jh3-20(T) ( = CGMCC 4.7201(T)= DSM 42170(T)). PMID:26297662

  2. Phytohabitans kaempferiae sp. nov., an endophytic actinomycete isolated from the leaf of Kaempferia larsenii.

    PubMed

    Niemhom, Nantawan; Chutrakul, Chanikul; Suriyachadkun, Chanwit; Thawai, Chitti

    2016-08-01

    A novel endophytic actinomycete, designated strain KK1-3T, which formed single spores and long chains of spores (more than 10 spores) was isolated from surface-sterilized Kaempferia larsenii leaf collected from Ubon Ratchathani province, Thailand. The isolate contained l-lysine, meso-diaminopimelic acid and hydroxyl diaminopimelic acid in the cell-wall peptidoglycan. The whole-cell sugars included glucose, mannose, rhamnose, ribose, galactose and xylose. The characteristic phospholipids were phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol and phosphoglycolipids. The predominant menaquinones were MK-10(H8), MK-10(H6) and MK-10(H4). The predominant cellular fatty acids were anteiso-C17 : 0 and iso-C16 : 0. The G+C content of the genomic DNA was 71 mol%. Phylogenetic analysis using 16S rRNA gene sequences revealed that strain KK1-3T should be classified as representing a member of the genus Phytohabitans. The similarity values of sequences between this strain and those of the closely related species, Phytohabitans houttuyneae K11-0057T (99.0 %), Phytohabitans suffuscus K07-0523T (98.9 %), Phytohabitans flavus K09-0627T (98.6 %) and Phytohabitans rumicisK11-0047T (98.1 %) were observed. The DNA-DNA hybridization result and some physiological and biochemical properties indicated that KK1-3T could be readily distinguished from its closest phylogenetic relatives. On the basis of these phenotypic and genotypic data, this strain represents a novel species, for which the name Phytohabitans kaempferiae sp. nov. is proposed. The type strain is strain KK1-3T (=BCC 66360T =NBRC 110005T). PMID:27126122

  3. Saccharopolyspora lacisalsi sp. nov., a novel halophilic actinomycete isolated from a salt lake in Xinjiang, China.

    PubMed

    Guan, Tong-Wei; Wu, Nan; Xia, Zhan-Feng; Ruan, Ji-Sheng; Zhang, Xiao-Ping; Huang, Ying; Zhang, Li-Li

    2011-05-01

    A novel actinomycete strain, designated TRM 40133(T), was isolated from a hypersaline habitat of Tarim basin in Xinjiang Province, north-west China. Its taxonomic status was determined using a polyphasic approach. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of the strain showed that it formed a well-seperated sub-branch within the radiation of the genus Saccharopolyspora. The highest levels of 16S rRNA gene sequence similarity was found between the strain TRM 40133(T) and Saccharopolyspora qijiaojingensis YIM 91168(T) (96.5%). The chemotaxonomic characteristics of the isolate are typical for the genus Saccharopolyspora. It contained meso-DAP as the diagnostic diamino acid. Whole cell hydrolysate contained arabinose, xylose, ribose and glucose. The diagnostic phospholipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol and two unknown phospholipids. The main menaquinone was MK-9(H(6)) and MK-9(H(4)). No mycolic acid was detected. The predominant cellular fatty acids were iso-C(16:0) and anteiso-C(17:0). The G+C content of the genomic DNA was 68.2 mol%. In addition, the strain TRM 40133(T) had a phenotypic profile that readily distinguished it from the recognized representatives of the genus Saccharopolyspora. The strain TRM 40133(T) therefore represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora lacisalsi sp. nov. is proposed. The type strain is TRM 40133(T) (=KCTC 19987(T) =CCTCC AA 2010012(T)). PMID:21461999

  4. Plantactinosporasoyae sp. nov., an endophytic actinomycete isolated from soybean root [Glycine max (L.) Merr].

    PubMed

    Guo, Xiaowei; Guan, Xuejiao; Liu, Chongxi; Jia, Feiyu; Li, Jiansong; Li, Jinmeng; Jin, Pinjiao; Li, Wenchao; Wang, Xiangjing; Xiang, Wensheng

    2016-07-01

    A novel actinomycete, designated strain NEAU-gxj3T, was isolated from soybean root [Glycine max (L.) Merr.] collected from Harbin, Heilongjiang Province, China, and characterized using a polyphasic approach. The 16S rRNA gene sequence of strain NEAU-gxj3T showed highest similarity to those of Micromonospora equina Y22T (98.2 %) and Plantactinospora endophytica YIM 68255T (98.0 %). Phylogenetic analysis based on the 16S rRNA gene and gyrB gene demonstrated that the isolate clustered with the members of the genus Plantactinospora. The chemotaxonomic properties of strain NEAU-gxj3Twere also consistent with those of members of the genus Plantactinospora. The cell wall contained meso-diaminopimelic acid and whole-cell sugars were xylose, glucose and galactose. The predominant menaquinones were MK-10(H6), MK-9(H8), MK-10(H2) and MK-10(H4). The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The major fatty acids were identified as anteiso-C17 : 0, iso-C16 : 0, iso-C15 : 0 and C15 : 0. A combination of DNA-DNA hybridization result and some phenotypic characteristics indicated that strain NEAU-gxj3Tcould be differentiated clearly from its closest phylogenetic relatives. Therefore, the strain is concluded to represent a novel species of the genus Plantactinospora, for which the name Plantactinospora soyae sp. nov. is proposed. The type strain is NEAU-gxj3T (=CGMCC 4.7221T=DSM 46832T). PMID:27089547

  5. Streptomyces canalis sp. nov., an actinomycete isolated from an alkali-removing canal.

    PubMed

    Xie, Yu-Xuan; Han, Xiao-Xue; Luo, Xiao-Xia; Xia, Zhan-Feng; Wan, Chuan-Xing; Zhang, Li-Li

    2016-08-01

    A novel actinomycete strain, designated TRM 46794-61T, was isolated from an alkali-removing canal in 14th Farms of Xinjiang Production and Construction Corps, north-west China. The isolate contained ll-diaminopimelic acid as the diagnostic diamino acid. The whole-cell sugar patterns of the isolate contained ribose, mannose and glucose. The polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannoside and two unidentified phospholipids. The predominant menaquinones were MK-9(H2), MK-9(H4), MK-9(H6) and MK-9(H8). The major fatty acids were iso-C16 : 0, anteiso-C17 : 0 and anteiso-C15 : 0. The G+C content of the DNA was 70.4 mol%. Phylogenetic analysis showed that strain TRM 46794-61T had a 16S rRNA gene sequence similarity of 97.6 % with the most closely related species with a validly published name, Streptomyces aidingensis TRM 46012T, and it could be distinguished from all species in the genus Streptomyces based on data from this polyphasic taxonomic study. However, DNA-DNA hybridization studies between strain TRM 46794-61T and S.aidingensis TRM 46012T showed only 45.4 % relatedness. On the basis of these data, strain TRM 46794-61T should be designated as a representative of a novel species of the genus Streptomyces, for which the name Streptomyces canalis sp. nov. is proposed. The type strain is TRM 46794-61T (=CCTCC AA 2015006T=KCTC 39568T). PMID:27217157

  6. Biosynthetic Potential of Phylogenetically Unique Endophytic Actinomycetes from Tropical Plants▿ †

    PubMed Central

    Janso, Jeffrey E.; Carter, Guy T.

    2010-01-01

    The culturable diversity of endophytic actinomycetes associated with tropical, native plants is essentially unexplored. In this study, 123 endophytic actinomycetes were isolated from tropical plants collected from several locations in Papua New Guinea and Mborokua Island, Solomon Islands. Isolates were found to be prevalent in roots but uncommon in leaves. Initially, isolates were dereplicated to the strain level by ribotyping. Subsequent characterization of 105 unique strains by 16S rRNA gene sequence analysis revealed that 17 different genera were represented, and rare genera, such as Sphaerisporangium and Planotetraspora, which have never been previously reported to be endophytic, were quite prevalent. Phylogenetic analyses grouped many of the strains into clades distinct from known genera within Thermomonosporaceae and Micromonosporaceae, indicating that they may be unique genera. Bioactivity testing and liquid chromatography-mass spectrometry (LC-MS) profiling of crude fermentation extracts were performed on 91 strains. About 60% of the extracts exhibited bioactivity or displayed LC-MS profiles with spectra indicative of secondary metabolites. The biosynthetic potential of 29 nonproductive strains was further investigated by the detection of putative polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) genes. Despite their lack of detectable secondary metabolite production in fermentation, most were positive for type I (66%) and type II (79%) PKS genes, and all were positive for NRPS genes. These results suggest that tropical plants from New Guinea and the adjacent archipelago are hosts to unique endophytic actinomycetes that possess significant biosynthetic potential. PMID:20472734

  7. High Sensitivity MEMS Strain Sensor: Design and Simulation

    PubMed Central

    Mohammed, Ahmed A. S.; Moussa, Walied A.; Lou, Edmond

    2008-01-01

    In this article, we report on the new design of a miniaturized strain microsensor. The proposed sensor utilizes the piezoresistive properties of doped single crystal silicon. Employing the Micro Electro Mechanical Systems (MEMS) technology, high sensor sensitivities and resolutions have been achieved. The current sensor design employs different levels of signal amplifications. These amplifications include geometric, material and electronic levels. The sensor and the electronic circuits can be integrated on a single chip, and packaged as a small functional unit. The sensor converts input strain to resistance change, which can be transformed to bridge imbalance voltage. An analog output that demonstrates high sensitivity (0.03mV/με), high absolute resolution (1με) and low power consumption (100μA) with a maximum range of ±4000με has been reported. These performance characteristics have been achieved with high signal stability over a wide temperature range (±50°C), which introduces the proposed MEMS strain sensor as a strong candidate for wireless strain sensing applications under harsh environmental conditions. Moreover, this sensor has been designed, verified and can be easily modified to measure other values such as force, torque…etc. In this work, the sensor design is achieved using Finite Element Method (FEM) with the application of the piezoresistivity theory. This design process and the microfabrication process flow to prototype the design have been presented.

  8. Transcriptomics-based strain optimization tool for designing secondary metabolite overproducing strains of Streptomyces coelicolor.

    PubMed

    Kim, Minsuk; Yi, Jeong Sang; Lakshmanan, Meiyappan; Lee, Dong-Yup; Kim, Byung-Gee

    2016-03-01

    In silico model-driven analysis using genome-scale model of metabolism (GEM) has been recognized as a promising method for microbial strain improvement. However, most of the current GEM-based strain design algorithms based on flux balance analysis (FBA) heavily rely on the steady-state and optimality assumptions without considering any regulatory information. Thus, their practical usage is quite limited, especially in its application to secondary metabolites overproduction. In this study, we developed a transcriptomics-based strain optimization tool (tSOT) in order to overcome such limitations by integrating transcriptomic data into GEM. Initially, we evaluated existing algorithms for integrating transcriptomic data into GEM using Streptomyces coelicolor dataset, and identified iMAT algorithm as the only and the best algorithm for characterizing the secondary metabolism of S. coelicolor. Subsequently, we developed tSOT platform where iMAT is adopted to predict the reaction states, and successfully demonstrated its applicability to secondary metabolites overproduction by designing actinorhodin (ACT), a polyketide antibiotic, overproducing strain of S. coelicolor. Mutants overexpressing tSOT targets such as ribulose 5-phosphate 3-epimerase and NADP-dependent malic enzyme showed 2 and 1.8-fold increase in ACT production, thereby validating the tSOT prediction. It is expected that tSOT can be used for solving other metabolic engineering problems which could not be addressed by current strain design algorithms, especially for the secondary metabolite overproductions. PMID:26369755

  9. Actinomycetes in the rhizosphere of semidesert soils of Mongolia

    NASA Astrophysics Data System (ADS)

    Norovsuren, Zh.; Zenova, G. M.; Mosina, L. V.

    2007-04-01

    The population density of actinomycetes in the desert-steppe soil, rhizosphere, and the above-ground parts of plants varies from tens to hundreds of thousands of colony-forming units (CFU) per gram of substrate. The actinomycetal complexes of the brown desert-steppe soil without plant roots are more diverse in their taxonomic composition than the actinomycetal complexes in the rhizosphere and the aboveground parts of plants. Additionally to representatives of the Streptomyces and Micromonospora genera, actinomycetes from the Nocardia, Saccharopolyspora, Thermomonospora, and Actinomadura genera were identified in the soil. The population density of actinomycetes in the rhizosphere and in the soil reached hundreds of thousand CFU/g; it considerably exceeded the population density of actinomycetes in the aboveground parts of plants. The maximum population density of actinomycetes was determined in the rhizosphere of Asparagus gobicus, Salsola pestifera, and Cleistogenes songorica.

  10. Streptomyces polyrhachii sp. nov., a novel actinomycete isolated from an edible Chinese black ant (Polyrhachis vicina Roger).

    PubMed

    Yu, Chao; Liu, Chongxi; Wang, Xiangjing; Zhao, Junwei; Yang, Lingyu; Gao, Ruixia; Zhang, Yuejing; Xiang, Wensheng

    2013-12-01

    A novel actinomycete, designated strain NEAU-ycm1(T), was isolated from an edible Chinese black ant (Polyrhachis vicina Roger) and characterized with a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of streptomycetes. Phylogenetic analysis based on the almost complete 16S rRNA gene sequence show that the novel isolate belongs to the genus Streptomyces and forms a separate subclade. The closest phylogenetic relatives were identified as the type strains of Streptomyces intermedius NBRC 13049(T) (97.74 %), Streptomyces aureoverticillatus NRRL B-3326(T) (97.69 %), Streptomyces rutgersensis NBRC 12819(T) (97.68 %), Streptomyces gougerotii NBRC 3198(T) (97.68 %) and Streptomyces diastaticus subsp. diastaticus NBRC 3714(T) (97.68 %). Similarities to other type strains of the genus Streptomyces were lower than 97.55 %. A comparison between strain NEAU-ycm1(T) and the closest related Streptomyces type strains revealed that it is different from them in morphological, physiological and biochemical characteristics. Therefore, it is proposed that NEAU-ycm1(T) (=CGMCC 4.7094(T) = DSM 42102(T)) represents a novel species of the genus of Streptomyces, for which the name Streptomyces polyrhachii sp. nov. is proposed. PMID:24002610

  11. Streptomyces bohaiensis sp. nov., a novel actinomycete isolated from Scomberomorus niphonius in the Bohai Sea.

    PubMed

    Pan, Hua-Qi; Cheng, Juan; Zhang, Dao-Feng; Yu, Su-Ya; Khieu, Thi-Nhan; Son, Chu Ky; Jiang, Zhao; Hu, Jiang-Chun; Li, Wen-Jun

    2015-04-01

    A novel actinomycete strain, designated 11A07(T), was isolated from young Scomberomorus niphonius in the Bohai Sea. Basic local alignment search tool analyses showed that this isolate had the highest 16S rRNA gene sequence similarity of 97.41% with Streptomyces rimosus subsp. paromomycinus DSM 41429(T). Phylogenetic tree revealed that strain 11A07(T) formed a distinct lineage clustered with Streptomyces panacagri Gsoil 519(T), Streptomyces sodiiphilus YIM 80305(T) and Streptomyces albus subsp. albus NRRL B-2365(T) having similarities of 97.30%, 97.10% and 96.83%, respectively. Multilocus sequence analysis further demonstrated that the new isolate was different from the selected representatives of Streptomyces as a separate phylogenetic line. Strain 11A07(T) produced straight or rectiflexibile spore chains with smooth surface, white aerial mycelia and brown diffusible pigments on international streptomyces project 2 medium. Maximum tolerated NaCl concentration for growth was 11.0%. Whole-cell sugars were mannose, ribose, glucose, galactose and xylose. The predominant menaquinones were MK-9(H2), MK-9(H4) and MK-9 (H6). The fatty-acid profile contained iso-C16:0, C18:0 10-methyl (tuberculostearic acid) and anteiso-C17:0 as the major compositions. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unknown phospholipid. The G+C content of the genomic DNA was 71.4 mol%. These morphological, phenotypic and chemotaxonomic properties showed that strain 11A07(T) could be readily distinguished from the most closely related members of the genus Streptomyces. Thus, based on the polyphasic taxonomic data, strain 11A07(T) (=JCM 19630(T)=CCTCC AA 2013020(T)=KCTC 29263(T)) represents a novel species within the genus Streptomyces, for which the name Streptomyces bohaiensis sp. nov. is proposed. PMID:25269462

  12. Phytoactinopolyspora alkaliphila sp. nov., an alkaliphilic actinomycete isolated from a saline-alkaline soil.

    PubMed

    Zhang, Yong-Guang; Lu, Xin-Hua; Ding, Yan-Bo; Zhou, Xing-Kui; Li, Li; Guo, Jian-Wei; Wang, Hong-Fei; Duan, Yan-Qing; Li, Wen-Jun

    2016-05-01

    An alkaliphilic, filamentous actinomycete, designated EGI 80629T, was isolated from a soil sample of Xinjiang, north-west China. Strain EGI 80629T grew at pH 6.0-11.0 (optimum pH 9.0-10.0) and in the presence of 0-13.0 % NaCl (optimum 3.0-5.0 %). The isolate formed fragmented substrate mycelia, and aerial hyphae with short spore chains with rod-like spores. Whole-cell hydrolysates of the isolate contained ll-diaminopimelic acid as the diagnostic diamino acid, and mannose and rhamnose as diagnostic sugars. The major fatty acids identified were iso-C15 : 0, iso-C16 : 0, anteiso-C15 : 0 and iso-C17 : 0. The predominant menaquinone was MK-9(H4), while the polar lipids were diphosphatidylglycerol, phosphatidylglycerol, two phosphatidylinositol mannosides, five unknown phospholipids, three unknown phosphoglycolipids, one unknown glycolipid, four unknown polar lipids and one unknown aminophospholipid. The G+C content of the genomic DNA was 67.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain EGI 80629T clustered with the genus Phytoactinopolyspora. The 16S rRNA gene sequence similarity between strain EGI 80629T and Phytoactinopolyspora endophytica EGI 60009T was 96.8 %. Based on morphological, chemotaxonomic and phylogenetic characteristics, strain EGI 80629T represents a novel species of the genus Phytoactinopolyspora, for which the name Phytoactinopolyspora alkaliphila sp. nov. is proposed. The type strain is EGI 80629T ( = CGMCC 4.7225T = KCTC 39701T). PMID:26920762

  13. Antimicrobial biosynthetic potential and genetic diversity of endophytic actinomycetes associated with medicinal plants.

    PubMed

    Gohain, Anwesha; Gogoi, Animesh; Debnath, Rajal; Yadav, Archana; Singh, Bhim P; Gupta, Vijai K; Sharma, Rajeev; Saikia, Ratul

    2015-10-01

    Endophytic actinomycetes are one of the primary groups that share symbiotic relationships with medicinal plants and are key reservoir of biologically active compounds. In this study, six selective medicinal plants were targeted for the first time for endophytic actinomycetes isolation from Gibbon Wild Life Sanctuary, Assam, India, during winter and summer and 76 isolates were obtained. The isolates were found to be prevalent in roots followed by stem and leaves. 16S rRNA gene sequence analysis revealed 16 genera, including rare genera, Verrucosispora, Isoptericola and Kytococcus, which have never been previously reported as endophytic. The genus Streptomyces (66%) was dominant in both seasons. Shannon's diversity index showed that Azadirachta indica (1.49), Rauwolfia serpentina (1.43) and Emblica officinalis (1.24) were relatively good habitat for endophytic actinomycetes. Antimicrobial strains showed prevalence of polyketide synthase (PKS) type-II (85%) followed by PKS type-I (14%) encoded in the genomes. Expression studies showed 12-fold upregulation of PKSII gene in seventh day of incubation for Streptomyces antibioticus (EAAG90). Our results emphasize that the actinomycetes assemblages within plant tissue exhibited biosynthetic systems encoding for important biologically active compounds. PMID:26347302

  14. Artificial Chromosomes to Explore and to Exploit Biosynthetic Capabilities of Actinomycetes

    PubMed Central

    Alduina, Rosa; Gallo, Giuseppe

    2012-01-01

    Actinomycetes are an important source of biologically active compounds, like antibiotics, antitumor agents, and immunosuppressors. Genome sequencing is revealing that this class of microorganisms has larger genomes relative to other bacteria and uses a considerable fraction of its coding capacity (5–10%) for the production of mostly cryptic secondary metabolites. To access actinomycetes biosynthetic capabilities or to improve the pharmacokinetic properties and production yields of these chemically complex compounds, genetic manipulation of the producer strains can be performed. Heterologous expression in amenable hosts can be useful to exploit and to explore the genetic potential of actinomycetes and not cultivable but interesting bacteria. Artificial chromosomes that can be stably integrated into the Streptomyces genome were constructed and demonstrated to be effective for transferring entire biosynthetic gene clusters from intractable actinomycetes into more suitable hosts. In this paper, the construction of several shuttle Escherichia coli-Streptomyces artificial chromosomes is discussed together with old and new strategies applied to improve heterologous production of secondary metabolites. PMID:22919271

  15. Red Soils Harbor Diverse Culturable Actinomycetes That Are Promising Sources of Novel Secondary Metabolites

    PubMed Central

    Guo, Xiaoxuan; Liu, Ning; Li, Xiaomin; Ding, Yun; Shang, Fei; Gao, Yongsheng; Ruan, Jisheng

    2015-01-01

    Red soils, which are widely distributed in tropical and subtropical regions of southern China, are characterized by low organic carbon, high content of iron oxides, and acidity and, hence, are likely to be ideal habitats for acidophilic actinomycetes. However, the diversity and biosynthetic potential of actinomycetes in such habitats are underexplored. Here, a total of 600 actinomycete strains were isolated from red soils collected in Jiangxi Province in southeast China. 16S rRNA gene sequence analysis revealed a high diversity of the isolates, which were distributed into 26 genera, 10 families, and 7 orders within the class Actinobacteria; these taxa contained at least 49 phylotypes that are likely to represent new species within 15 genera. The isolates showed good physiological potentials for biosynthesis and biocontrol. Chemical screening of 107 semirandomly selected isolates spanning 20 genera revealed the presence of at least 193 secondary metabolites from 52 isolates, of which 125 compounds from 39 isolates of 12 genera were putatively novel. Macrolides, polyethers, diketopiperazines, and siderophores accounted for most of the known compounds. The structures of six novel compounds were elucidated, two of which had a unique skeleton and represented characteristic secondary metabolites of a putative novel Streptomyces phylotype. These results demonstrate that red soils are rich reservoirs for diverse culturable actinomycetes, notably members of the families Streptomycetaceae, Pseudonocardiaceae, and Streptosporangiaceae, with the capacity to synthesize novel bioactive compounds. PMID:25724963

  16. Modeling and observer design for recombinant Escherichia coli strain.

    PubMed

    Nadri, M; Trezzani, I; Hammouri, H; Dhurjati, P; Longin, R; Lieto, J

    2006-03-01

    A mathematical model for recombinant bacteria which includes foreign protein production is developed. The experimental system consists of an Escherichia Coli strain and plasmid pIT34 containing genes for bioluminescence and production of a protein, beta-galactosidase. This recombinant strain is constructed to facilitate on-line estimation and control in a complex bioprocess. Several batch experiments are designed and performed to validate the developed model. The design of a model structure, the identification of the model parameters and the estimation problem are three parts of a joint design problem. A nonlinear observer is designed and an experimental evaluation is performed on a batch fermentation process to estimate the substrate consumption. PMID:16411071

  17. Actinomycetes: A Source of Lignocellulolytic Enzymes

    PubMed Central

    Saini, Anita; Aggarwal, Neeraj K.; Sharma, Anuja; Yadav, Anita

    2015-01-01

    Lignocellulose is the most abundant biomass on earth. Agricultural, forest, and agroindustrial activities generate tons of lignocellulosic wastes annually, which present readily procurable, economically affordable, and renewable feedstock for various lignocelluloses based applications. Lignocelluloses are the focus of present decade researchers globally, in an attempt to develop technologies based on natural biomass for reducing dependence on expensive and exhaustible substrates. Lignocellulolytic enzymes, that is, cellulases, hemicellulases, and lignolytic enzymes, play very important role in the processing of lignocelluloses which is prerequisite for their utilization in various processes. These enzymes are obtained from microorganisms distributed in both prokaryotic and eukaryotic domains including bacteria, fungi, and actinomycetes. Actinomycetes are an attractive microbial group for production of lignocellulose degrading enzymes. Various studies have evaluated the lignocellulose degrading ability of actinomycetes, which can be potentially implemented in the production of different value added products. This paper is an overview of the diversity of cellulolytic, hemicellulolytic, and lignolytic actinomycetes along with brief discussion of their hydrolytic enzyme systems involved in biomass modification. PMID:26793393

  18. Actinomycete infections in humans--a review.

    PubMed

    Schaal, K P; Lee, H J

    1992-06-15

    Diseases caused by pathogenic aerobic and facultatively anaerobic actinomycetes differ considerably with respect to their etiology, pathogenesis, clinical appearance and epidemiology. Facultatively anaerobic (fermentative) actinomycetes may not only be involved etiologically in the three classical forms of cervicofacial, thoracic and abdominal actinomycoses, but also in infections of the female genital organs, the eye, the tissue adjacent to dental implantation elements and tooth extraction wounds. The species distribution of the fermentative actinomycetes isolated from these conditions varied to a certain, but characteristic, extent, as did the concomitant actinomycotic flora. The sex ratio reported for human Actinomyces infections (male:female = 3:1) appeared to be restricted to actinomycotic abscesses and empyemas. The prevailing pathogenic, obligately aerobic actinomycete species in Germany was found to be Nocardia farcinica followed by Nocardia asteroides. The comparatively high incidence of N. farcinica infections was chiefly due to the occurrence of nosocomial postoperative wound infections by this pathogen observed in two German hospitals. Besides surgical treatment, immunosuppressive treatment appeared to be the most common factor predisposing for nocardiosis. Recent observations strongly suggested that the spectrum of human nocardial infections in Germany has been changing, as regards the overall incidence, the prevalence of N. farcinica, the sex ratio, the mean age of patients, as well as the role of N. farcinica as a possibly important nosocomial pathogen. PMID:1612438

  19. Diversity of actinomycetes isolated from Challenger Deep sediment (10,898 m) from the Mariana Trench.

    PubMed

    Pathom-Aree, Wasu; Stach, James E M; Ward, Alan C; Horikoshi, Koki; Bull, Alan T; Goodfellow, Michael

    2006-06-01

    Thirty-eight actinomycetes were isolated from sediment collected from the Mariana Trench (10,898 m) using marine agar and media selective for actinomycetes, notably raffinose-histidine agar. The isolates were assigned to the class Actinobacteria using primers specific for members of this taxon. The phylogenetic analysis based on 16S rRNA gene sequencing showed that the isolates belonged to the genera Dermacoccus, Kocuria, Micromonospora, Streptomyces, Tsukamurella and Williamsia. All of the isolates were screened for genes encoding nonribosomal peptide and polyketide synthetases. Nonribosomal peptide synthetase sequences were detected in more than half of the isolates and polyketide synthases type I (PKS-I) were identified in five out of 38 strains. The Streptomyces isolates produced several unusual secondary metabolites, including a PKS-I associated product. In initial testing for piezotolerance, the Dermacoccus strain MT1.1 grew at elevated hydrostatic pressures. PMID:16538400

  20. Isolation and characterization of novel marine-derived actinomycete taxa rich in bioactive metabolites.

    PubMed

    Magarvey, Nathan A; Keller, Jessica M; Bernan, Valerie; Dworkin, Martin; Sherman, David H

    2004-12-01

    A unique selective enrichment procedure has resulted in the isolation and identification of two new genera of marine-derived actinobacteria. Approximately 90% of the microorganisms cultured by using the presented method were from the prospective new genera, a result indicative of its high selectivity. In this study, 102 actinomycetes were isolated from subtidal marine sediments collected from the Bismarck Sea and the Solomon Sea off the coast of Papua New Guinea. A combination of physiological parameters, chemotaxonomic characteristics, distinguishing 16S rRNA gene sequences, and phylogenetic analysis based on 16S rRNA genes provided strong evidence for the two new genera (represented by strains of the PNG1 clade and strain UMM518) within the family Micromonosporaceae. Biological activity testing of fermentation products from the new marine-derived actinomycetes revealed that several had activities against multidrug-resistant gram-positive pathogens, malignant cells, and vaccinia virus replication. PMID:15574955

  1. Design and development of a MEMS capacitive bending strain sensor

    NASA Astrophysics Data System (ADS)

    Aebersold, J.; Walsh, K.; Crain, M.; Martin, M.; Voor, M.; Lin, J.-T.; Jackson, D.; Hnat, W.; Naber, J.

    2006-05-01

    The design, modeling, fabrication and testing of a MEMS-based capacitive bending strain sensor utilizing a comb drive is presented. This sensor is designed to be integrated with a telemetry system that will monitor changes in bending strain to assist with the diagnosis of spinal fusion. ABAQUS/CAE finite-element analysis (FEA) software was used to predict sensor actuation, capacitance output and avoid material failure. Highly doped boron silicon wafers with a low resistivity were fabricated into an interdigitated finger array employing deep reactive ion etching (DRIE) to create 150 µm sidewalls with 25 µm spacing between the adjacent fingers. The sensor was adhered to a steel beam and subjected to four-point bending to mechanically change the spacing between the interdigitated fingers as a function of strain. As expected, the capacitance output increased as an inverse function of the spacing between the interdigitated fingers. At the unstrained state, the capacitive output was 7.56 pF and increased inversely to 17.04 pF at 1571 µɛ of bending strain. The FEA and analytical models were comparable with the largest differential of 0.65 pF or 6.33% occurring at 1000 µɛ. Advantages of this design are a dice-free process without the use of expensive silicon-on-insulator (SOI) wafers.

  2. New Benzoxazine Secondary Metabolites from an Arctic Actinomycete

    PubMed Central

    Moon, Kyuho; Ahn, Chan-Hong; Shin, Yoonho; Won, Tae Hyung; Ko, Keebeom; Lee, Sang Kook; Oh, Ki-Bong; Shin, Jongheon; Nam, Seung-Il; Oh, Dong-Chan

    2014-01-01

    Two new secondary metabolites, arcticoside (1) and C-1027 chromophore-V (2), were isolated along with C-1027 chromophore-III and fijiolides A and B (3–5) from a culture of an Arctic marine actinomycete Streptomyces strain. The chemical structures of 1 and 2 were elucidated through NMR, mass, UV, and IR spectroscopy. The hexose moieties in 1 were determined to be d-glucose from a combination of acid hydrolysis, derivatization, and gas chromatographic analyses. Arcticoside (1) and C-1027 chromophore-V (2), which have a benzoxazine ring, inhibited Candida albicans isocitrate lyase. Chromophore-V (2) exhibited significant cytotoxicity against breast carcinoma MDA-MB231 cells and colorectal carcinoma cells (line HCT-116), with IC50 values of 0.9 and 2.7 μM, respectively. PMID:24796308

  3. Glucanolytic Actinomycetes Antagonistic to Phytophthora fragariae var. rubi, the Causal Agent of Raspberry Root Rot

    PubMed Central

    Valois, D.; Fayad, K.; Barasubiye, T.; Garon, M.; Dery, C.; Brzezinski, R.; Beaulieu, C.

    1996-01-01

    A collection of about 200 actinomycete strains was screened for the ability to grow on fragmented Phytophthora mycelium and to produce metabolites that inhibit Phytophthora growth. Thirteen strains were selected, and all produced (beta)-1,3-, (beta)-1,4-, and (beta)-1,6-glucanases. These enzymes could hydrolyze glucans from Phytophthora cell walls and cause lysis of Phytophthora cells. These enzymes also degraded other glucan substrates, such as cellulose, laminarin, pustulan, and yeast cell walls. Eleven strains significantly reduced the root rot index when inoculated on raspberry plantlets. PMID:16535313

  4. Study of the effects of urban organic residues on the distribution of culturable actinomycetes in a Tunisian agricultural soil.

    PubMed

    Mokni-Tlili, Sonia; Jaoua, Leila; Murano, Fumio; Jedidi, Naceur; Hassen, Abdennaceur

    2009-05-01

    The main objective of this investigation was to identify a collection of actinomycetes isolates and to study the influence of amendment [municipal solid waste compost (MSWC) and farmyard manure (FM)] on their distribution in agricultural soil. For this purpose, a phenotypic and molecular characterization of 226 isolates collected from soil (with and without amendment) and 55 isolates from MSWC and FM was developed. The phenotypic study showed that the majority of strains isolated belong to the genus Streptomyces. By using the 16S rDNA polymerase chain reaction-restriction fragment length polymorphism method (restriction digest using six enzymes AluI, HhaI, MspI, TaqI, RsaI and HaeIII), two clusters were found: Streptomyces, dominant genus and Amycolatopsis, followed by Nocardioides. This result agreed with phylogeny revealed by 16S rDNA sequencing. The number of these actinomycetes in soil increased with FM or MSWC application. The studied soil is a potential source for isolation of actinomycetes, especially Streptomyces, and the application of organic amendment to the soil appeared to have an impact on the diversity of actinomycetes. Amendment of the soil with MSWC and FM significantly increased the number of actinomycetes due to the contribution of bacteria originally contained in biowastes and/or by stimulation of the endogenous soil micro-organisms. PMID:19423577

  5. Aerobic and microaerophilic actinomycetes of typical agropeat and peat soils

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Gryadunova, A. A.; Pozdnyakov, A. I.; Zvyagintsev, D. G.

    2008-02-01

    A high number (from tens of thousands to millions of CFU/g of soil) of actinomycetes and a high diversity of genera were found in typical peat and agropeat soils. Agricultural use increases the number and diversity of the actinomycete complexes of the peat soils. In the peat soils, the actinomycete complex is represented by eight genera: Streptomyces, Micromonospora, Streptosporangium, Actinomadura, Microbispora, Saccharopolyspora, Saccharomonospora, and Microtetraspora. A considerable share of sporangial forms in the actinomycete complex of the peat soils not characteristic of the zonal soils was revealed. The number of actinomycetes that develop under aerobic conditions is smaller by 10-100 times than that of aerobic forms in the peat soils. Among the soil actinomycetes of the genera Streptomyces, Micromonospora, Streptosporangium, Actinomadura, Microbispora, and Microtetraspora, the microaerophilic forms were found; among the Saccharopolyspora and Saccharomonospora, no microaerophilic representatives were revealed.

  6. Phytoactinopolyspora endophytica gen. nov., sp. nov., a halotolerant filamentous actinomycete isolated from the roots of Glycyrrhiza uralensis F.

    PubMed

    Li, Li; Ma, Jin-Biao; Abdalla Mohamad, Osama; Li, Shan-Hui; Osman, Ghenijan; Li, Yan-Qiong; Guo, Jian-Wei; Hozzein, Wael N; Li, Wen-Jun

    2015-08-01

    A novel endophytic actinomycete, designated strain EGI 60009T, was isolated from the roots of Glycyrrhiza uralensis F. collected from Xinjiang Province, north-west China. The isolate was able to grow in the presence of 0-9% (w/v) NaCl. Strain EGI 60009T had particular morphological properties: the substrate mycelia fragmented into rod-like elements and aerial mycelia differentiated into short spore chains. ll-2, 6-Diaminopimelic acid was the cell-wall diamino acid and rhamnose, galactose and glucose were the cell-wall sugars. MK-9(H4) was the predominant menaquinone. The major fatty acids of strain EGI 60009T were iso-C15 : 0, anteiso-C15 : 0, anteiso-C17 : 0, iso-C17 : 0, iso-C17 : 1 and I/anteiso-C17 : 0 B. Mycolic acids were absent. The DNA G+C content of strain EGI 60009T was 70.4 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain EGI 60009T belongs to the family Jiangellaceae and formed a distinct clade in the phylogenetic tree. 16S rRNA gene sequence similarities between strain EGI 60009T and other members of the genera Jiangella and Haloactinopolyspora were 96.1-96.4 and 95.7-96.0%, respectively. Based on these results and supported by morphological, physiological and chemotaxonomic data and numerous phenotypic differences, a novel species of a new genus, Phytoactinopolyspora endophytica gen. nov., sp. nov., is proposed. The type strain of Phytoactinopolyspora endophytica is EGI 60009T ( = KCTC 29657T = CPCC204078T). PMID:25964514

  7. Nonomuraea syzygii sp. nov., an endophytic actinomycete isolated from the roots of a jambolan plum tree (Syzygium cumini L. Skeels).

    PubMed

    Rachniyom, Hathairat; Matsumoto, Atsuko; Indananda, Chantra; Duangmal, Kannika; Takahashi, Yoko; Thamchaipenet, Arinthip

    2015-04-01

    A novel endophytic actinomycete, designated strain GKU 164(T), was isolated from the roots of a jambolan plum tree (Syzygium cumini L. Skeels), collected at Khao Khitchakut National Park, Chantaburi province, Thailand. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain formed a distinct clade within the genus Nonomuraea , and was most closely related to Nonomuraea monospora PT708(T) (98.77% 16S rRNA gene sequence similarity) and Nonomuraea thailandensis KC-061(T) (98.73%). Strain GKU 164(T) formed a branched substrate and aerial hyphae that generated single spores with rough surfaces. The cell wall contained meso-diaminopimelic acid. The whole-cell sugars were madurose, galactose, mannose, ribose, rhamnose and glucose. The N-acyl type of muramic acid was acetyl. The predominant menaquinone was MK-9(H4) with minor amounts of MK-9(H6), MK-9(H2) and MK-9(H0). The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositolmannosides, phosphatidylmonomethylethanolamine, hydroxy-phosphatidylmonomethylethanolamine, an unidentified aminophosphoglycolipid and four unknown phospholipids. The major fatty acids were iso-C(16 : 0) and 10-methyl C(17 : 0). The genomic DNA G+C content was 70.4 mol%. Significant differences in the morphological, chemotaxonomical, and biochemical data together with DNA-DNA relatedness values between strain GKU 164(T) and type strains of closely related species, clearly demonstrated that strain GKU 164(T) represents a novel species of the genus Nonomuraea , for which the name Nonomuraea syzygii sp. nov. is proposed. The type strain is GKU 164(T) ( = BCC 70457(T) = NBRC 110400(T)). PMID:25634947

  8. Streptomyces iconiensis sp. nov. and Streptomyces smyrnaeus sp. nov., two halotolerant actinomycetes isolated from a salt lake and saltern.

    PubMed

    Tatar, Demet; Guven, Kiymet; Spröer, Cathrin; Klenk, Hans-Peter; Sahin, Nevzat

    2014-09-01

    The taxonomic positions of two novel actinomycetes, designated strains BNT558(T) and SM3501(T), were established by using a polyphasic approach. The organisms had chemical and morphological features that were consistent with their classification in the genus Streptomyces. The whole-cell hydrolysates of the two strains contained ll-diaminopimelic acid as the diagnostic diamino acid. The predominant menaquinones were MK-9(H6) and MK-9(H8) for strain BNT558(T) and MK-9(H8) and MK-9(H6) for strain SM3501(T). Major fatty acids of the strains were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The polar lipid profile of strain BNT558(T) contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, one unidentified glycolipid and one unidentified aminophospholipid, while that of strain SM3501(T) consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine, three unidentified atypical aminolipids, one unidentified aminolipid and two unidentified glycolipids. The G+C contents of the genomic DNA were 70.2 and 69.6 mol% for strains BNT558(T) and SM3501(T), respectively. 16S rRNA gene sequence data supported the classification of the isolates in the genus Streptomyces and showed that they formed two distinct branches within the genus. Based on almost-complete 16S rRNA gene sequences, strain BNT558(T) was related most closely to Streptomyces albiaxialis NRRL B-24327(T) and strain SM3501(T) was related most closely to Streptomyces cacaoi subsp. cacaoi NBRC 12748(T). DNA-DNA relatedness between each of the isolates and its closest phylogenetic neighbours showed that they belonged to distinct species. The two isolates were readily distinguished from one another and from the type strains of the other species classified in the genus Streptomyces based on a combination of phenotypic and genotypic properties. Based on the genotypic and phenotypic evidence, strains BNT558(T) and SM3501(T) belong to two

  9. Antimicrobial Activities of Some Actinomycetes Isolated from Different Rhizospheric Soils in Tunisia.

    PubMed

    Trabelsi, Ines; Oves, Daniel; Manteca, Angel; Genilloud, Olga; Altalhi, Abdullah; Nour, Mohamed

    2016-08-01

    Fifty four isolates of actinomycetes were collected from four different rhizospheric soils: 18 strains from palm tree bark and soil, 12 strains from an olive field soil, 9 strains from a coastal forest, and 15 strains from an agriculture soil situated in the Algerian-Tunisian border (Oum Tboul). Based on morphological and cultural characters, the isolates were classified as Streptomyces (42 strains), Micromonospora (4 strains), Pseudonocardia (1 strain), Actinomadura (1 strain), Nocardia (1 strain), and non-Streptomyces (5 strains). More than half of the isolates inhibited at least one tested pathogenic microorganisms in liquid culture. In addition, antimicrobial activities of some strains were tested on solid culture. Several bioactive compounds were identified by liquid chromatography joined with low-resolution mass spectroscopy (LC/MS) and analysed by MEDINA's database and by the dictionary of natural products Chapman & Hall. An interesting chlorinated compound with the molecular formula C20H37ClN2O4, produced by three different strains (SF1, SF2, and SF5), was subject of an attempted purification. However, it was demonstrated using confocal microscopy and LC/MS high resolution that this compound is produced only on solid culture. These three potential antimicrobial isolates showed high similarity with Streptomyces thinghirensis and Streptomyces lienomycini, in terms of morphological characteristics and 16S rRNA gene sequences (bootstrap 97 %). All these findings prove the high antimicrobial diversity of the studied soils. The potential of the selected and other relatively unexplored extreme environments constitute a source of interesting actinomycete strains producing several biologically active secondary metabolites. PMID:27139253

  10. Halophilic and halotolerant actinomycetes from a marine saltern of Goa, India producing anti-bacterial metabolites.

    PubMed

    Ballav, Shuvankar; Kerkar, Savita; Thomas, Sabu; Augustine, Nimmy

    2015-03-01

    Marine salterns are estuarine ecosystems in Goa, receiving inputs from riverine and marine waters. The Salinity fluctuates between 0 and 300 psu which makes it a conducive niche for salt tolerant and salt loving Actinomycetales. Halotolerant and halophilic Actinomycetales producing anti-bacterial metabolites were studied from crystallizer pond sediments of Ribandar saltern, Goa. Three media viz. Starch casein, R2A and Inorganic salt starch agar at four different salinities (35, 50, 75 and 100 psu) were used for isolation. R2A agar at 35 psu was the most preferred by hypersaline actinomycetes. The dominant group was halotolerant Streptomyces spp. others being rare actinomycetes viz. Nocardiopsis, Micromonospora and Kocuria spp. More than 50% of the isolates showed anti-bacterial activity against one or more of the fifteen human pathogens tested. Eight strains from 4 genera showed consistent anti-bacterial activity and studied in detail. Most halotolerant isolates grew from 0 to 75 psu, with optimum antibiotic production at 35 psu whereas halophiles grew at 20 to 100 psu with optimum antibiotic production at 35 psu. Four Streptomyces strains showed multiple inhibition against test organisms while four rare actinomycetes were specific in their inhibitory activity. This is the first report of a halophilic Kocuria sp., Nocardiopsis sp., and halotolerant Micromonospora sp. producing anti-bacterial compound(s) against Staphylococcus aureus, Staphylococcus citreus, and Vibrio cholerae, respectively. Sequential extraction with varying polarity of organic solvents showed that the extracts inhibited different test pathogens. These results suggest that halophilic and halotolerant actinomycetes from marine salterns are a potential source of anti-bacterial compounds. PMID:25449757

  11. Design-oriented aeroservoelastic optimization of strain-actuated aircraft

    NASA Astrophysics Data System (ADS)

    Jackson, Timothy W.

    An integrated design-oriented aeroservoelastic optimization capability for strain-actuated aircraft is presented. This capability is called SMART and it encompasses a suite of computer applications created for conceptual and preliminary design of aircraft augmented with "smart" actuation technologies. The SMART suite of applications includes: (1) a dedicated pre-processor for vehicle geometry, material, actuator, mechanism, and sensor layout; (2) a dedicated finite element automesher for conventional and strain-actuated flight vehicles; (3) integration of structural dynamics with a state of the art commercial unsteady aerodynamics code (ZAERO) via automated pre- and post-processors; (4) a database architecture for analyzing multiple designs and flight conditions; and (5) automated open- and closed-loop aeroservoelastic (ASE) model preparation. The analysis techniques used as the basis for SMART are suitable (within the range of application of linear theory) for modeling real flight vehicles with real large-scale structural, aerodynamic, and control systems. These techniques include: (6) dedicated linear finite element infrastructure for modeling conventional and strain-actuated (temperature and voltage induced) flight structures; (7) dedicated static and dynamic finite element solvers; (8) state space stability analysis for coupled aeroservoelastic systems; (9) computational tools for LQR controller design; and (10) analysis tools for the calculation of random response of linear systems to random inputs. SMART can compute: (11) static aeroelastic deformations and stresses in trimmed maneuvering elastic airplanes; (12) open-loop aeroelastic poles; (13) closed-loop (control by LQR) aeroservoelastic poles; (14) gust response (random gusts) of the open-loop and closed-loop aeroservoelastic system, and, also, when aerodynamic loads are not present; and (15) deformation and stresses of passive or actively-controlled structures subject to dynamic and static loads. To

  12. An actinomycete isolate from solitary wasp mud nest having strong antibacterial activity and kills the Candida cells due to the shrinkage and the cytosolic loss

    PubMed Central

    Kumar, Vijay; Naik, Bindu; Gusain, Omprakash; Bisht, Gajraj S.

    2014-01-01

    An actinomycetes strain designated as MN 2(6) was isolated from the solitary wasp mud nest. The isolate was identified using polyphasic taxonomy. It produced the extensive branched brown substrate and white aerial hyphae that changed into grayish black. The aerial mycelia produced the spiral spore chains with rugose spore surface. The growth was observed between temperature range of 27–37°C, pH 8–10 and below salt concentration of 6% (w/v). The comparative analysis of 16S rRNA gene sequence and phylogenetic relationship showed that strain MN 2(6) lies in clade with Streptomyces hygroscopicus subsp. hygroscopicus NRRL 2387T, Streptomyces sporocinereus NBRC 100766T and Streptomyces demainii NRRL B-1478T with which it shares a 16S rRNA gene sequence similarity of 99.3%. The strain MN 2(6) can be differentiated from type strains based on phenotypic characteristics. The strain MN 2(6) showed most promising activity against Gram-positive, Gram-negative bacteria, acid-fast bacilli and Candida species suggesting broad-spectrum characteristics of the active metabolite. Evaluation of anti-candidal activity of the metabolite of strain MN 2(6) by scanning electron microscopy (SEM) revealed changed external morphology of yeast. It kills the Candida cells due to the shrinkage and the cytosolic loss. However, further studies are required to elucidate the structure of the active metabolite produced by the isolate MN 2(6). PMID:25191320

  13. Lignin-solubilizing ability of actinomycetes isolated from termite (Termitidae) gut. [Streptomyces viridosporus

    SciTech Connect

    Pasti, M.B.; Crawford, D.L. ); Pometto, A.L., III ); Nuti, M.P. )

    1990-07-01

    The lignocellulose-degrading abilities of 11 novel actinomycete strains isolated from termite gut were determined and compared with that of the well-characterized actinomycete, Streptomyces viridosporus T7A. Lignocellulose bioconversion was followed by (i) monitoring the degradation of ({sup 14}C)lignin- and ({sup 14}C)cellulose-labeled phloem of Abies concolor to {sup 14}CO{sub 2} and {sup 14}C-labeled water-soluble products, (ii) determining lignocellulose, lignin, and carbohydrate losses resulting from growth on a lignocellulose substrate prepared from corn stalks (Zea mays), and (iii) quantifying production of a water-soluble lignin degradation intermediate (acid-precipitable polymeric lignin). Of the assays used, total lignocellulose weight loss was most useful in determining overall bioconversion ability but not in identifying the best lignin-solubilizing strains. A screening procedure based on {sup 14}CO{sub 2} evolution from ({sup 14}C-lignin)lignocellulose combined with measurement of acid-precipitable polymeric lignin yield was the most effective in identifying lignin-solubilizing strains. For the termite gut strains, the pH of the medium showed no increase after 3 weeks of growth on lignocellulose. This is markedly different from the pattern observed with S. viridosporus T7A, which raises the medium pH considerably. Production of extracellular peroxidases by the 11 strains and S. viridosporus T7A was followed for 5 days in liquid cultures. On the basis of an increase of specific peroxidase activity in the presence of lignocellulose in the medium, the actinomycetes could be placed into the same three groups.

  14. Micromonospora taraxaci sp. nov., a novel endophytic actinomycete isolated from dandelion root (Taraxacum mongolicum Hand.-Mazz.).

    PubMed

    Zhao, Junwei; Guo, Lifeng; He, Hairong; Liu, Chongxi; Zhang, Yuejing; Li, Chuang; Wang, Xiangjing; Xiang, Wensheng

    2014-10-01

    A novel actinomycete, designated strain NEAU-P5(T), was isolated from dandelion root (Taraxacum mongolicum Hand.-Mazz.). Strain NEAU-P5(T) showed closest 16S rRNA gene sequence similarity to Micromonospora chokoriensis 2-19/6(T) (99.5%), and phylogenetically clustered with Micromonospora violae NEAU-zh8(T) (99.3%), M. saelicesensis Lupac 09(T) (99.0%), M. lupini Lupac 14N(T) (98.8%), M. zeae NEAU-gq9(T) (98.4%), M. jinlongensis NEAU-GRX11(T) (98.3%) and M. zamorensis CR38(T) (97.9%). Phylogenetic analysis based on the gyrB gene sequence also indicated that the isolate clustered with the above type strains except M. violae NEAU-zh8(T). The cell-wall peptidoglycan consisted of meso-diaminopimelic acid and glycine. The major menaquinones were MK-9(H8), MK-9(H6) and MK-10(H2). The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were C(16:0), iso-C(15:0) and C(17:0). Furthermore, some physiological and biochemical properties and low DNA-DNA relatedness values enabled the strain to be differentiated from members of closely related species. Therefore, it is proposed that strain NEAU-P5(T) represents a novel species of the genus Micromonospora, for which the name Micromonospora taraxaci sp. nov. is proposed. The type strain is NEAU-P5(T) (=CGMCC 4.7098(T) = DSM 45885(T)). PMID:25082023

  15. Identification of actinomycetes from plant rhizospheric soils with inhibitory activity against Colletotrichum spp., the causative agent of anthracnose disease

    PubMed Central

    2011-01-01

    Background Colletotrichum is one of the most widespread and important genus of plant pathogenic fungi worldwide. Various species of Colletotrichum are the causative agents of anthracnose disease in plants, which is a severe problem to agricultural crops particularly in Thailand. These phytopathogens are usually controlled using chemicals; however, the use of these agents can lead to environmental pollution. Potential non-chemical control strategies for anthracnose disease include the use of bacteria capable of producing anti-fungal compounds such as actinomycetes spp., that comprise a large group of filamentous, Gram positive bacteria from soil. The aim of this study was to isolate actinomycetes capable of inhibiting the growth of Colletotrichum spp, and to analyze the diversity of actinomycetes from plant rhizospheric soil. Results A total of 304 actinomycetes were isolated and tested for their inhibitory activity against Colletotrichum gloeosporioides strains DoA d0762 and DoA c1060 and Colletotrichum capsici strain DoA c1511 which cause anthracnose disease as well as the non-pathogenic Saccharomyces cerevisiae strain IFO 10217. Most isolates (222 out of 304, 73.0%) were active against at least one indicator fungus or yeast. Fifty four (17.8%) were active against three anthracnose fungi and 17 (5.6%) could inhibit the growth of all three fungi and S. cerevisiae used in the test. Detailed analysis on 30 selected isolates from an orchard at Chanthaburi using the comparison of 16S rRNA gene sequences revealed that most of the isolates (87%) belong to the genus Streptomyces sp., while one each belongs to Saccharopolyspora (strain SB-2) and Nocardiopsis (strain CM-2) and two to Nocardia (strains BP-3 and LK-1). Strains LC-1, LC-4, JF-1, SC-1 and MG-1 exerted high inhibitory activity against all three anthracnose fungi and yeast. In addition, the organic solvent extracts prepared from these five strains inhibited conidial growth of the three indicator fungi

  16. A diaminopimelic acid auxotrophic Escherichia coli donor provides improved counterselection following intergeneric conjugation with actinomycetes.

    PubMed

    Allard, Nancy; Garneau, Daniel; Poulin-Laprade, Dominic; Burrus, Vincent; Brzezinski, Ryszard; Roy, Sébastien

    2015-08-01

    Considering the medical, biotechnological, and economical importance of actinobacteria, there is a continuous need to improve the tools for genetic engineering of a broad range of these microorganisms. Intergeneric conjugation has proven to be a valuable yet imperfect tool for this purpose. The natural resistance of many actinomycetes to nalidixic acid (Nal) is generally exploited to eliminate the sensitive Escherichia coli donor strain following conjugation. Nevertheless, Nal can delay growth and have other unexpected effects on the recipient strain. To provide an improved alternative to antibiotics, we propose a postconjugational counterselection using a diaminopimelic acid (DAP) auxotrophic donor strain. The DAP-negative phenotype was obtained by introducing a dapA deletion into the popular methylase-negative donor strain E. coli ET12567/pUZ8002. The viability of ET12567 and its ΔdapA mutant exposed to DAP deprivation or Nal selection were compared in liquid pure culture and after mating with Streptomyces coelicolor. Results showed that death of the E. coli ΔdapA Nal-sensitive donor strain occurred more efficiently when subjected to DAP deprivation than when exposed to Nal. Our study shows that postconjugational counterselection based on DAP deprivation circumvents the use of antibiotics and will facilitate the transfer of plasmids into actinomycetes with high biotechnological potential, yet currently not accessible to conjugative techniques. PMID:26166710

  17. Saccharopolyspora subtropica sp. nov., a thermophilic actinomycete isolated from soil of a sugar cane field.

    PubMed

    Wu, Hao; Liu, Bin; Pan, Shangli

    2016-05-01

    A novel thermophilic actinomycete, designated strain T3T, was isolated from a soil sample of a sugar cane field. The strain grew at 25-60 °C (optimum 37-50 °C), at pH 6.0-11.0 (optimum 7.0-9.0) and with 0-12.0 % (w/v) NaCl (optimum 0-7 %). The aerial mycelium was white and the vegetative mycelium was colourless to pale yellow. The substrate mycelium fragmented into rod-shaped elements after 4-5 days at 50 °C. The aerial mycelium formed flexuous chains of 5-20 spores per chain; the oval-shaped spores had spiny surfaces and were non-motile. The organism contained meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The whole-cell sugars consisted of arabinose, galactose and ribose. The cellular fatty acid profile consisted mainly of anteiso-C17 : 0, iso-C17 : 0 and iso-C16 : 0. The quinone system was composed predominantly of MK-9(H4). The phospholipids detected were diphosphatidylglycerol, phosphatidylcholine, phosphatidylinositol, phosphatidylethanolamine, phosphatidylmethylethanolamine and ninhydrin-positive glycophospholipids. The DNA G+C content of strain T3T was 71.3 mol%. The organism showed a combination of morphological and chemotaxonomic properties typical of members of the genus Saccharopolyspora. In the 16S rRNA gene tree of Saccharopolyspora it formed a distinct phyletic line and was related most closely to Saccharopolyspora thermophila 216T. However, the phenotypic characteristics of strain T3T were significantly different from those of S. thermophila 216T and DNA-DNA hybridization revealed a low level of relatedness (28.6-32.3 %) between them. Based on the phenotypic and phylogenetic data, strain T3T represents a novel species in the genus Saccharopolyspora, for which the name Saccharopolyspora subtropica sp. nov. is proposed. The type strain is T3T ( = DSM 46801T = CGMCC 4.7206T). PMID:26882893

  18. Thermoactinomyces guangxiensis sp. nov., a thermophilic actinomycete isolated from mushroom compost.

    PubMed

    Wu, Hao; Liu, Bin; Pan, Shangli

    2015-09-01

    A novel thermophilic actinomycete, designated strain CD-1(T), was isolated from mushroom compost in Nanning, Guangxi province, China. The strain grew at 37-55 °C (optimum 45-50 °C), pH 6.0-11.0 (optimum pH 7.0-9.0) and with 0-2.0% NaCl (optimum 0-1.0%), formed well-developed white aerial mycelium and pale-yellow vegetative mycelium, and single endospores (0.8-1.0 μm diameter) were borne on long sporophores (2-3 μm length). The endospores were spherical-polyhedron in shape with smooth surface. Based on its phenotypic and phylogenetic characteristics, strain CD-1(T) is affiliated to the genus Thermoactinomyces. It contained meso-diaminopimelic acid as the diagnostic diamino acid; the whole-cell sugars were ribose and glucose. Major fatty acids were iso-C15 :  0, C16 : 0, anteiso-C15  : 0 and iso-C17  : 0. MK-7 was the predominant menaquinone. The polar phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylethanolamine containing hydroxylated fatty acids, ninhydrin-positive glycophospholipid, an unknown phospholipid and glycolipids. The G+C content of the genomic DNA was 48.8%. 16S rRNA gene sequence analysis showed that the organism was closely related to Lihuaxuella thermophila YIM 77831(T) (95.69% sequence similarity), Thermoactinomyces daqus H-18(T) (95.49%), Laceyella putida KCTC 3666(T) (95.05%), Thermoactinomyces vulgaris KCTC 9076(T) (95.01%) and Thermoactinomyces intermedius JCM 3312(T) (94.55%). Levels of DNA-DNA relatedness between strain CD-1T and Lihuaxuella thermophila JCM 18059(T), Thermoactinomyces daqus DSM 45914(T), Laceyella putida JCM 8091(T), Thermoactinomyces vulgaris JCM 3162(T) and Thermoactinomyces intermedius JCM 3312(T) were low (22.8, 33.3, 24.7, 29.4 and 30.0%, respectively). A battery of phenotypic, genotypic and DNA-DNA relatedness data indicated that strain CD-1T represented a novel species of the genus Thermoactinomyces, for which the name Thermoactinomyces guangxiensis sp. nov

  19. Secondary Metabolites from an Actinomycete from Vietnam's East Sea.

    PubMed

    Thi, Quyen Vu; Tran, Van Hieu; Mai, Huong Doan Thi; Le, Cong Vinh; Hong, Min Le Thi; Murphy, Brian T; Chau, Van Minh; Pham, Van Cuong

    2016-03-01

    Analysis of an antimicrobial extract prepared from culture broth of the marine-derived actinomycete Nocardiopsis sp. (strain G057) led to the isolation of twelve compounds, 1-12. Compound 1 (2-[(2R-hydroxypropanoyl)amino]benzamide) was found to be a new enantiomeric isomer while compounds 2 (3-acetyl-4-hydroxycinnoline) and 3 (3,3'-bis-indole) were isolated from a natural source for the first time. The structures of 1-12 were determined by analyses of MS and 2D NMR data. All compounds were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Compound 1 selectively inhibited Escherichia coli (MIC: 16 µg/mL). Compounds 2 and 3 exhibited antimicrobial activity against several strains of both Gram-positive and Gram-negative bacteria, and the yeast Candida albicans. Cytotoxic evaluation of compounds 1-3 against four cancer cell lines (KB, LU-1, HepG-2 and MCF-7) indicated that compound 3 produced a weak inhibition against KB and LU cell lines. Two remaining compounds, 1 and 2 were not cytotoxic, even at the concentration of 128 µg/mL. PMID:27169191

  20. Isolation of Mutants of the Nitrogen-Fixing Actinomycete Frankia

    PubMed Central

    Kakoi, Kentaro; Yamaura, Masatoshi; Kamiharai, Toshihito; Tamari, Daiki; Abe, Mikiko; Uchiumi, Toshiki; Kucho, Ken-Ichi

    2014-01-01

    Frankia is a nitrogen (N)-fixing multicellular actinomycete which establishes root-nodule symbiosis with actinorhizal plants. Several aspects of Frankia N fixation and symbiosis are distinct, but genes involved in the specific features are largely unknown because of the lack of an efficient mutant screening method. In this study, we isolated mutants of Frankia sp. strain CcI3 using hyphae fragments mutagenized by chemical mutagens. Firstly, we isolated uracil auxotrophs as gain-of-function mutants resistant to 5-fluoroorotic acid (5-FOA). We obtained seven 5-FOA resistant mutants, all of which required uracil for growth. Five strains carried a frame shift mutation in orotidine-5′-phosphate decarboxylase gene and two carried an amino acid substitution in the orotate phosphoribosyltransferase gene. Secondly, we isolated mutants showing loss-of-function phenotypes. Mutagenized hyphae were fragmented by ultrasound and allowed to multiply at their tips. Hyphae were fragmented again and short fragments were enriched by filtration through 5 μm pores filters. Next-generation and Sanger sequencing revealed that colonies formed from the short hyphae fragments consisted of cells with an identical genotype. From the mutagenized colony population, we isolated three pigmentation mutants and a mutant with reduced N-fixation activity. These results indicate that our procedure is useful for the isolation of loss-of-function mutants using hyphae of Frankia. PMID:24389412

  1. Screening and characterization of protease producing actinomycetes from marine saltern.

    PubMed

    Suthindhiran, Krish; Jayasri, Mangalam Achuthananda; Dipali, Dipa; Prasar, Apurva

    2014-10-01

    In the course of systematic screening program for bioactive actinomycetes, an alkaline protease producing halophilic strain Actinopolyspora sp. VITSDK2 was isolated from marine saltern, Southern India. The strain was identified as Actinopolyspora based on its phenotypic and phylogenetic characters. The protease was partially purified using ammonium sulfate precipitation and subsequently by DEAE cellulose column chromatography. The enzyme was further purified using HPLC and the molecular weight was found to be 22 kDa as determined by SDS-PAGE analysis. The purified protease exhibited pH stability in a wide range of 4-12 with optimum at 10.0. The enzyme was found to be stable between 25 and 80 °C and displayed a maximum activity at 60 °C. The enzyme activity was increased marginally in presence of Mn(2+) , Mg(2+) , and Ca(2+) and decreased in presence of Cu(2+) . PMSF and DFP completely inhibited the activity suggesting it belongs to serine protease. Further, the proteolytic activity was abolished in presence of N-tosyl-L-lysine chloromethyl ketone suggesting this might be chymotrypsin-like serine protease. The protease was 96% active when kept for 10 days at room temperature. The results indicate that the enzyme belong to chymotrypsin-like serine protease exhibiting both pH and thermostability, which can be used for various applications in industries. PMID:24136565

  2. Isolation of mutants of the nitrogen-fixing actinomycete Frankia.

    PubMed

    Kakoi, Kentaro; Yamaura, Masatoshi; Kamiharai, Toshihito; Tamari, Daiki; Abe, Mikiko; Uchiumi, Toshiki; Kucho, Ken-Ichi

    2014-01-01

    Frankia is a nitrogen (N)-fixing multicellular actinomycete which establishes root-nodule symbiosis with actinorhizal plants. Several aspects of Frankia N fixation and symbiosis are distinct, but genes involved in the specific features are largely unknown because of the lack of an efficient mutant screening method. In this study, we isolated mutants of Frankia sp. strain CcI3 using hyphae fragments mutagenized by chemical mutagens. Firstly, we isolated uracil auxotrophs as gain-of-function mutants resistant to 5-fluoroorotic acid (5-FOA). We obtained seven 5-FOA resistant mutants, all of which required uracil for growth. Five strains carried a frame shift mutation in orotidine-5'-phosphate decarboxylase gene and two carried an amino acid substitution in the orotate phosphoribosyltransferase gene. Secondly, we isolated mutants showing loss-of-function phenotypes. Mutagenized hyphae were fragmented by ultrasound and allowed to multiply at their tips. Hyphae were fragmented again and short fragments were enriched by filtration through 5 μm pores filters. Next-generation and Sanger sequencing revealed that colonies formed from the short hyphae fragments consisted of cells with an identical genotype. From the mutagenized colony population, we isolated three pigmentation mutants and a mutant with reduced N-fixation activity. These results indicate that our procedure is useful for the isolation of loss-of-function mutants using hyphae of Frankia. PMID:24389412

  3. Nocardiopsis oceani sp. nov. and Nocardiopsis nanhaiensis sp. nov., actinomycetes isolated from marine sediment of the South China Sea.

    PubMed

    Pan, Hua-Qi; Zhang, Dao-Feng; Li, Li; Jiang, Zhao; Cheng, Juan; Zhang, Yong-Guang; Wang, Hong-Fei; Hu, Jiang-Chun; Li, Wen-Jun

    2015-10-01

    Two actinomycete strains, designated 10A08AT and 10A08BT, were isolated from marine sediment samples of the South China Sea and their taxonomic positions were determined by a polyphasic approach. The two Gram-stain-positive, aerobic strains produced branched substrate mycelium and aerial hyphae, and no diffusible pigment was produced in the media tested. At maturity, spore chains were formed on aerial hyphae and all mycelium fragmented with age. Whole-cell hydrolysates of both strains contained meso-diaminopimelic acid and no diagnostic sugars. Their predominant menaquinones (>10 %) were MK-9(H4), MK-9(H6) and MK-10(H6) for strain 10A08AT and MK-9(H4), MK-9(H6), MK-10(H4) and MK-10(H6) for strain 10A08BT. The polar lipids detected from the two strains were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and unknown phosphoglycolipids and phospholipids. The major fatty acids (>10 %) of both strains were iso-C16 : 0 and summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B). The genomic DNA G+C contents of strains 10A08AT and 10A08BT were 70.9 and 71.6 mol%, respectively. On the basis of 16S rRNA gene sequence similarities, the two strains were shown to be most closely related to species of the genus Nocardiopsis. DNA–DNA hybridization relatedness values of < 70 % between these two isolates and their closest neighbour, Nocardiopsis terrae YIM 90022T, and between the two strains supported the conclusion that they represent two novel species. Based on phylogenetic analysis and phenotypic and genotypic data, it is concluded that the two isolates belong to the genus Nocardiopsis, and the names Nocardiopsis oceani sp. nov. (type strain 10A08AT = DSM 45931T = BCRC 16951T) and Nocardiopsis nanhaiensis sp. nov. (type strain 10A08BT = CGMCC 47227T = BCRC 16952T) are proposed. PMID:26297579

  4. Actinomycete complexes in soils of industrial and residential zones in the city of Kirov

    NASA Astrophysics Data System (ADS)

    Shirokikh, I. G.; Solov'eva, E. S.; Ashikhmina, T. Ya.

    2014-02-01

    The number, diversity, and structure of the actinomycetal complexes in the soils of the industrial and residential zones of the city of Kirov are considered. The total content of mobile cadmium, zinc, lead, iron, and nickel in the soils of the industrial biotopes was 1.8 and 6.0 times higher than their concentration in the soils of the residential and background zones, respectively. In the heavy metal (HM)-polluted soils, the share of actinomycetes in the total number of prokaryotes and the relative abundance of the micromono-spores in the actinomycetal complex were much higher and the species diversity of the streptomycetes was lower than these characteristics in the soils of the residential zone. The differences in the composition of the mycelial prokaryote complexes appear to be related to the selective resistance of some of their representatives to heavy metals. The possibility to select the strains resistant to HMs and suitable for use in the bioremediation of polluted soils is considered.

  5. Trehangelins A, B and C, novel photo-oxidative hemolysis inhibitors produced by an endophytic actinomycete, Polymorphospora rubra K07-0510.

    PubMed

    Nakashima, Takuji; Okuyama, Ryuki; Kamiya, Yoshiyuki; Matsumoto, Atsuko; Iwatsuki, Masato; Inahashi, Yuki; Yamaji, Kenzaburo; Takahashi, Yōko; Ōmura, Satoshi

    2013-06-01

    Three new natural products, designated trehangelins A, B and C, were isolated by solvent extraction, silica gel and octadecylsilyl silica gel column chromatographies and subsequent preparative HPLC from the cultured broth of an endophytic actinomycete strain, Polymorphospora rubra K07-0510. The trehangelins consisted of a trehalose moiety and two angelic acid moieties. Trehangelins A (IC50 value, 0.1 mg ml(-1)) and C (IC50 value, 0.4 mg ml(-1)), with symmetric structures, showed potent inhibitory activity against hemolysis of red blood cells induced by light-activated pheophorbide a. However, trehangelin B, with an asymmetric structure, displayed only a slight inhibition (IC50 value, 1.0 mg ml(-1)). PMID:23591606

  6. Modification of the protein expression pattern induced in the nitrogen-fixing actinomycete Frankia sp. strain ACN14a-tsr by root exudates of its symbiotic host Alnus glutinosa and cloning of the sodF gene.

    PubMed

    Hammad, Y; Maréchal, J; Cournoyer, B; Normand, P; Domenach, A M

    2001-06-01

    Two-dimensional (2-D) polyacrylamide gel electrophoresis was used to detect proteins induced in Frankia sp. strain ACN14a-tsr by root exudates of its symbiotic host, Alnus glutinosa. The 5 most prominent proteins were purified from 2-D gels and characterized by N-terminal sequencing. All of these proteins had a high percentage of similarity with known stress proteins. One protein match was the Fe superoxide dismutase (Fe-SOD), another was a tellurite resistance protein (Ter), the third was a bacterioferritin comigratory protein (Bcp); and two matches, differing only by their isoelectric point, were the same small heat shock protein (Hsp), a major immune reactive protein found in mycobacteria. This suggests that the symbiotic microorganism Frankia, first responds with a normal stress response to toxic root products of its symbiotic host plant. To confirm its identity, the gene corresponding to the Fe-SOD protein, sodF was isolated from a genomic library by a PCR-approach and sequenced. It is the first stress response gene characterized in Frankia. PMID:11467730

  7. Knitted Strain Sensors: Impact of Design Parameters on Sensing Properties

    PubMed Central

    Atalay, Ozgur; Kennon, William Richard

    2014-01-01

    This paper presents a study of the sensing properties exhibited by textile-based knitted strain sensors. Knitted sensors were manufactured using flat-bed knitting technology, and electro-mechanical tests were subsequently performed on the specimens using a tensile testing machine to apply strain whilst the sensor was incorporated into a Wheatstone bridge arrangement to allow electrical monitoring. The sensing fabrics were manufactured from silver-plated nylon and elastomeric yarns. The component yarns offered similar diameters, bending characteristics and surface friction, but their production parameters differed in respect of the required yarn input tension, the number of conductive courses in the sensing structure and the elastomeric yarn extension characteristics. Experimental results showed that these manufacturing controls significantly affected the sensing properties of the knitted structures such that the gauge factor values, the working range and the linearity of the sensors varied according to the knitted structure. These results confirm that production parameters play a fundamental role in determining the physical behavior and the sensing properties of knitted sensors. It is thus possible to manipulate the sensing properties of knitted sensors and the sensor response may be engineered by varying the production parameters applied to specific designs. PMID:24608010

  8. Computational methods in metabolic engineering for strain design.

    PubMed

    Long, Matthew R; Ong, Wai Kit; Reed, Jennifer L

    2015-08-01

    Metabolic engineering uses genetic approaches to control microbial metabolism to produce desired compounds. Computational tools can identify new biological routes to chemicals and the changes needed in host metabolism to improve chemical production. Recent computational efforts have focused on exploring what compounds can be made biologically using native, heterologous, and/or enzymes with broad specificity. Additionally, computational methods have been developed to suggest different types of genetic modifications (e.g. gene deletion/addition or up/down regulation), as well as suggest strategies meeting different criteria (e.g. high yield, high productivity, or substrate co-utilization). Strategies to improve the runtime performances have also been developed, which allow for more complex metabolic engineering strategies to be identified. Future incorporation of kinetic considerations will further improve strain design algorithms. PMID:25576846

  9. Designing topological states by pressure, strain, and functionalization

    NASA Astrophysics Data System (ADS)

    Schwingenschlogl, Udo

    Various examples of the design of topological states by means of first-principles calculations are discussed. The presentation focusses on the design parameters (1) pressure, (2) strain, and (3) functionalization. TiTe2 is found to be unusually accessible to strain effects and the first compound that under hydrostatic pressure (up to experimentally reasonable 30 GPa) is subject to a series of four topological phase transitions, which are related to band inversions at different points of the Brillouin zone. Therefore, TiTe2 enables experimental access to all these transitions in a single compound. Phase transitions in TlBiS2 and TlSbS2 are identified by parity analysis and by calculating the surface states. Zero, one, and four Dirac cones are found for the (111) surfaces of both TlBiS2 and TlSbS2 when the pressure grows, which confirms trivial-nontrivial-trivial phase transitions. The Dirac cones at the M points are anisotropic with large out-of-plane component. TlBiS2 shows normal, topological, and topological crystalline insulator phases under hydrostatic pressure, thus being the first compound to exhibit a phase transition from a topological to a topological crystalline insulator. While monolayer arsenic and arsenic antimonide are semiconductors (direct band gap at the Γ point), fluorination results for both compounds in Dirac cones at the K points. Fluorinated monolayer arsenic shows a band gap of 0.16 eV due to spin-orbit coupling and fluorinated arsenic antimonide a larger band gap of 0.37 eV due to inversion symmetry breaking. Spin-orbit coupling induces spin splitting similar to monolayer MoS2. Phonon calculations confirm that both materials are dynamically stable. Calculations of the edge states of nanoribbons by the tight-binding method demonstrate that fluorinated arsenic is topologically nontrivial in contrast to fluorinated arsenic antimonide.

  10. Broad Spectrum Antimicrobial Activity of Forest-Derived Soil Actinomycete, Nocardia sp. PB-52

    PubMed Central

    Sharma, Priyanka; Kalita, Mohan C.; Thakur, Debajit

    2016-01-01

    A mesophilic actinomycete strain designated as PB-52 was isolated from soil samples of Pobitora Wildlife Sanctuary of Assam, India. Based on phenotypic and molecular characteristics, the strain was identified as Nocardia sp. which shares 99.7% sequence similarity with Nocardia niigatensis IFM 0330 (NR_112195). The strain is a Gram-positive filamentous bacterium with rugose spore surface which exhibited a wide range of antimicrobial activity against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA), Gram-negative bacteria, and yeasts. Optimization for the growth and antimicrobial activity of the strain PB-52 was carried out in batch culture under shaking condition. The optimum growth and antimicrobial potential of the strain were recorded in GLM medium at 28°C, initial pH 7.4 of the medium and incubation period of 8 days. Based on polyketide synthases (PKS) and non-ribosomal peptide synthetases (NRPS) gene-targeted PCR amplification, the occurrence of both of these biosynthetic pathways was detected which might be involved in the production of antimicrobial compounds in PB-52. Extract of the fermented broth culture of PB-52 was prepared with organic solvent extraction method using ethyl acetate. The ethyl acetate extract of PB-52 (EA-PB-52) showed lowest minimum inhibitory concentration (MIC) against S. aureus MTCC 96 (0.975 μg/mL) whereas highest was recorded against Klebsiella pneumoniae ATCC 13883 (62.5 μg/mL). Scanning electron microscopy (SEM) revealed that treatment of the test microorganisms with EA-PB-52 destroyed the targeted cells with prominent loss of cell shape and integrity. In order to determine the constituents responsible for its antimicrobial activity, EA-PB-52 was subjected to chemical analysis using gas chromatography-mass spectrometry (GC-MS). GC-MS analysis showed the presence of twelve different chemical constituents in the extract, some of which are reported to possess diverse biological activity. These

  11. Isolation and characterization of potential antibiotic producing actinomycetes from water and sediments of Lake Tana, Ethiopia

    PubMed Central

    Gebreyohannes, Gebreselema; Moges, Feleke; Sahile, Samuel; Raja, Nagappan

    2013-01-01

    Objective To isolate, evaluate and characterize potential antibiotic producing actinomycetes from water and sediments of Lake Tana, Ethiopia. Methods A total of 31 strains of actinomycetes were isolated and tested against Gram positive and Gram negative bacterial strains by primary screening. In the primary screening, 11 promising isolates were identified and subjected to solid state and submerged state fermentation methods to produce crude extracts. The fermented biomass was extracted by organic solvent extraction method and tested against bacterial strains by disc and agar well diffusion methods. The isolates were characterized by using morphological, physiological and biochemical methods. Results The result obtained from agar well diffusion method was better than disc diffusion method. The crude extract showed higher inhibition zone against Gram positive bacteria than Gram negative bacteria. One-way analysis of variance confirmed most of the crude extracts were statistically significant at 95% confidence interval. The minimum inhibitory concentration and minimum bactericidal concentration of crude extracts were 1.65 mg/mL and 3.30 mg/mL against Staphylococcus aureus, and 1.84 mg/mL and 3.80 mg/mL against Escherichia coli respectively. The growth of aerial and substrate mycelium varied in different culture media used. Most of the isolates were able to hydrolysis starch and urea; able to survive at 5% concentration of sodium chloride; optimum temperature for their growth was 30 °C. Conclusions The results of the present study revealed that freshwater actinomycetes of Lake Tana appear to have immense potential as a source of antibacterial compounds. PMID:23730554

  12. Meroparamycin production by newly isolated Streptomyces sp. strain MAR01: taxonomy, fermentation, purification and structural elucidation.

    PubMed

    El-Naggar, Moustafa Y; El-Assar, Samy A; Abdul-Gawad, Sahar M

    2006-08-01

    Twelve actinomycete strains were isolated from Egyptian soil. The isolated actinomycete strains were then screened with regard to their potential to generate antibiotics. The most potent of the producer strains was selected and identified. The cultural and physiological characteristics of the strain identified the strain as a member of the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene (1.5 kb) of the most potent strain evidenced a 99% similarity with Streptomyces spp. and S. aureofaciens 16S rRNA genes, and the isolated strain was ultimately identified as Streptomyces sp. MAR01. The extraction of the fermentation broth of this strain resulted in the isolation of one major compound, which was active in vitro against gram-positive, gram-negative representatives and Candida albicans. The chemical structure of this bioactive compound was elucidated based on the spectroscopic data obtained from the application of MS, IR, UV, 1H NMR, 13C NMR, and elemental analysis techniques. Via comparison to the reference data in the relevant literature and in the database search, this antibiotic, which had a molecular formula of C19H29NO2 and a molecular weight of 303.44, was determined to differ from those produced by this genus as well as the available known antibiotics. Therefore, this antibiotic was designated Meroparamycin. PMID:16953179

  13. In Vitro Evaluation of Enzymatic and Antifungal Activities of Soil-Actinomycetes Isolates and Their Molecular Identification by PCR

    PubMed Central

    Keikha, Nasser; Ayatollahi Mousavi, Seyyed Amin; Nakhaei, Ali Reza; Yadegari, Mohammad Hossein; Shahidi Bonjar, Gholam Hossein; Amiri, Somayyeh

    2015-01-01

    Background: Human cutaneous infection caused by a homogeneous group of keratinophilic fungi called dermatophytes. These fungi are the most common infectious agents in humans that are free of any population and geographic area. Microsporum canis is a cause of dermatophytosis (Tinea) in recent years in Iran and atypical strain has been isolated in Iran. Its cases occur sporadically due to M. canis transmission from puppies and cats to humans. Since this pathogenic dermatophyte is eukaryotes, chemical treatment with antifungal drugs may also affect host tissue cells. Objectives: The aim of the current study was to find a new antifungal agent of soil-Actinomycetes from Kerman province against M. canis and Actinomycete isolates were identified by PCR. Materials and Methods: A number of hundred Actinomycete isolated strains were evaluated from soil of Kerman province, for their antagonistic activity against the M. canis. M. canis of the Persian Type Culture Collection (PTCC) was obtained from the Iranian Research Organization for Science and Technology (IROST). Electron microscope studies of these isolates were performed based on the physiological properties of these antagonists including lipase, amylase, protease and chitinase activities according to the relevant protocols and were identified using gene 16SrDNA. Results: In this study the most antagonist of Actinomycete isolates with antifungal activity against M. canis isolates of L1, D5, Ks1m, Km2, Kn1, Ks8 and Ks1 were shown in vitro. Electron microscopic studies showed that some fungal strains form spores, mycelia and spore chain. Nucleotide analysis showed that Ks8 had maximum homology (98%) to Streptomyces zaomyceticus strain xsd08149 and L1 displayed 100% homology to Streptomyces sp. HVG6 using 16SrDNA studies. Conclusions: Our findings showed that Streptomyces has antifungal effects against M. canis. PMID:26060560

  14. Terrabacter terrae sp. nov., a novel actinomycete isolated from soil in Spain.

    PubMed

    Montero-Barrientos, Marta; Rivas, Raúl; Velázquez, Encarna; Monte, Enrique; Roig, Manuel G

    2005-11-01

    A Gram-positive, aerobic, long-rod-shaped, non-spore-forming bacterium (strain PPLB(T)) was isolated from soil mixed with Iberian pig hair. This actinomycete showed keratinase activity in vitro when chicken feathers were added to the culture medium. Strain PPLB(T) was oxidase-negative and catalase-positive and produced lipase and esterase lipase. This actinomycete grew at 40 degrees C on nutrient agar and in the same medium containing 5 % (w/v) NaCl. Growth was observed with many different carbohydrates as the sole carbon source. On the basis of 16S rRNA gene sequence similarity, strain PPLB(T) was shown to belong to the genus Terrabacter of the family Intrasporangiaceae. Strain PPLB(T) showed 98.8 % 16S rRNA gene sequence similarity to Terrabacter tumescens. Chemotaxonomic data, such as the main ubiquinone (MK-8), the main polar lipids (phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylinositol) and the main fatty acids (i-C(15 : 0), ai-C(15 : 0), i-C(16 : 0) and ai-C(17 : 0)) supported the affiliation of strain PPLB(T) to the genus Terrabacter. The G+C content of the DNA was 71 mol%. The results of DNA-DNA hybridization (36.6 % relatedness between Terrabacter tumescens and strain PPLB(T)) and physiological and biochemical tests suggested that strain PPLB(T) belongs to a novel species of the genus Terrabacter, for which the name Terrabacter terrae sp. nov. is proposed. The type strain is PPLB(T) (=CECT 3379T=LMG 22921T). PMID:16280515

  15. Nocarimidazoles A and B from a Marine-Derived Actinomycete of the Genus Nocardiopsis.

    PubMed

    Leutou, Alain S; Yang, Inho; Kang, Heonjoong; Seo, Eun Kyung; Nam, Sang-Jip; Fenical, William

    2015-11-25

    Chemical investigation of a marine-derived actinomycete isolated from marine sediments collected off the coast of southern California and identified as a Nocardiopsis sp. (strain CNQ115) led to the isolation of two new 4-aminoimidazole alkaloids, nocarimidazoles A (1) and B (2). The chemical structures of nocarimidazoles A and B were assigned by interpretation of NMR spectroscopic data and through methylation to yield monomethyl and dimethyl derivatives. Nocarimidazoles A and B possess a 4-aminoimidazole ring combined with a conjugated carbonyl side chain, which is rarely found in microbial secondary metabolites. PMID:26474119

  16. Complete Genome Sequence of the Soil Actinomycete Kocuria rhizophila▿

    PubMed Central

    Takarada, Hiromi; Sekine, Mitsuo; Kosugi, Hiroki; Matsuo, Yasunori; Fujisawa, Takatomo; Omata, Seiha; Kishi, Emi; Shimizu, Ai; Tsukatani, Naofumi; Tanikawa, Satoshi; Fujita, Nobuyuki; Harayama, Shigeaki

    2008-01-01

    The soil actinomycete Kocuria rhizophila belongs to the suborder Micrococcineae, a divergent bacterial group for which only a limited amount of genomic information is currently available. K. rhizophila is also important in industrial applications; e.g., it is commonly used as a standard quality control strain for antimicrobial susceptibility testing. Sequencing and annotation of the genome of K. rhizophila DC2201 (NBRC 103217) revealed a single circular chromosome (2,697,540 bp; G+C content of 71.16%) containing 2,357 predicted protein-coding genes. Most of the predicted proteins (87.7%) were orthologous to actinobacterial proteins, and the genome showed fairly good conservation of synteny with taxonomically related actinobacterial genomes. On the other hand, the genome seems to encode much smaller numbers of proteins necessary for secondary metabolism (one each of nonribosomal peptide synthetase and type III polyketide synthase), transcriptional regulation, and lateral gene transfer, reflecting the small genome size. The presence of probable metabolic pathways for the transformation of phenolic compounds generated from the decomposition of plant materials, and the presence of a large number of genes associated with membrane transport, particularly amino acid transporters and drug efflux pumps, may contribute to the organism's utilization of root exudates, as well as the tolerance to various organic compounds. PMID:18408034

  17. Actinomycetes in garden soils of the city of Kirov

    NASA Astrophysics Data System (ADS)

    Shirokikh, I. G.; Solov'eva, E. S.; Ashikhmina, T. Ya.

    2013-05-01

    The population density, diversity, and structure of the actinomycetic complexes were studied in garden soils of the city of Kirov. The relationships between the structure of the complexes and the acidity, the concentrations of the mobile forms of heavy metals, and the soil humus content were analyzed. The specific features of the actinomycetic population in the garden soils of the city in comparison with the transport ecotopes and suburban territories were revealed. It was demonstrated that the actinomycetic complexes in the garden soils preserve their structural similarity with the actinomycetic complexes of the suburban forest parks despite certain changes in the composition of the dominant species and the relative abundance of the separate taxa. The obtained data indicate that the garden plots in the city contribute to the preservation of ecologically balanced ecosystems.

  18. Genome Sequence of Streptomyces aureofaciens ATCC Strain 10762

    PubMed Central

    Gradnigo, Julien S.; Somerville, Greg A.; Huether, Michael J.; Kemmy, Richard J.; Johnson, Craig M.; Oliver, Michael G.

    2016-01-01

    Streptomyces aureofaciens is a Gram-positive actinomycete that produces the antibiotics tetracycline and chlortetracycline. Here, we report the assembly and initial annotation of the draft genome sequence of S. aureofaciens ATCC strain 10762. PMID:27340076

  19. Eco-taxonomic insights into actinomycete symbionts of termites for discovery of novel bioactive compounds.

    PubMed

    Kurtböke, D Ipek; French, John R J; Hayes, R Andrew; Quinn, Ronald J

    2015-01-01

    Termites play a major role in foraging and degradation of plant biomass as well as cultivating bioactive microorganisms for their defense. Current advances in "omics" sciences are revealing insights into function-related presence of these symbionts, and their related biosynthetic activities and genes identified in gut symbiotic bacteria might offer a significant potential for biotechnology and biodiscovery. Actinomycetes have been the major producers of bioactive compounds with an extraordinary range of biological activities. These metabolites have been in use as anticancer agents, immune suppressants, and most notably, as antibiotics. Insect-associated actinomycetes have also been reported to produce a range of antibiotics such as dentigerumycin and mycangimycin. Advances in genomics targeting a single species of the unculturable microbial members are currently aiding an improved understanding of the symbiotic interrelationships among the gut microorganisms as well as revealing the taxonomical identity and functions of the complex multilayered symbiotic actinofloral layers. If combined with target-directed approaches, these molecular advances can provide guidance towards the design of highly selective culturing methods to generate further information related to the physiology and growth requirements of these bioactive actinomycetes associated with the termite guts. This chapter provides an overview on the termite gut symbiotic actinoflora in the light of current advances in the "omics" science, with examples of their detection and selective isolation from the guts of the Sunshine Coast regional termite Coptotermes lacteus in Queensland, Australia. PMID:24817085

  20. Extremophilic and extremotolerant actinomycetes in different soil types

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Manucharova, N. A.; Zvyagintsev, D. G.

    2011-04-01

    Problems on the resistance of soil actinomycetes to various environmental factors (pH, salinity, temperature, and moisture) are discussed. Actinomycetes as a special group of prokaryotes were revealed to have a greater range of tolerance to these factors than was thought earlier. The regularities of the distribution of extremophilic and extremotolerant actinomycetes developing in unusual for mycelial bacteria conditions, their structural-functional characteristics, and their taxonomic composition were determined. The predominance of acidophilic representatives of the Micromonospora genus in acid soils (typical peat, soddy-podzolic, and taiga podzol) and the haloalkaliphilic Streptomyces pluricilirescens and S. prunicolor species in desert saline soils are shown. The specific features of the actinomycete complexes on thermal fields of the weakly developed stratified volcanic soils are described. In these complexes, the thermophilic forms were represented only by species of the Micromonospora genus; and the mesophilic forms, by Microbispora species. In the periodically heated desert soils, among the thermophilic actinomycetes, representatives of rare Actinomadura, Saccharopolyspora and Streptosporangium genera along with Streptomyces species were indicated. The mechanisms of the resistance of the actinomycetes to the extreme environmental conditions are discussed.

  1. Protoplast fusion and gene recombination in the uncommon Actinomycete Planobispora rosea producing GE2270.

    PubMed

    Beltrametti, Fabrizio; Barucco, Daniele; Rossi, Roberta; Selva, Enrico; Marinelli, Flavia

    2007-07-01

    An efficient method for protoplast generation for the uncommon actinomycete Planobispora rosea, the producer of the thiazolylpeptide antibiotic GE2270, was developed using a combination of hen egg white lysozyme and Streptomyces globisporus mutanolysin. This method converted more than 70% of vegetative mycelium to protoplasts, which were then regenerated with 50% efficiency in an optimized medium. When P. rosea protoplasts were efficiently fused, recombination between different antibiotic (streptomycin and gentamicin) resistance markers originated sensitive strains (str(s)gen(s)) at frequencies as high as 18% and double resistant fusants (str(r)gen(r)) at frequencies as high as 29%. Double resistant fusants showed GE2270 productivity intermediate between the productivity of the parental strains. Protoplast generation and fusion in P. rosea makes whole genome shuffling feasible as an approach to be used alternately with classical random mutagenesis in industrial strain improvement programs. PMID:17721003

  2. Diversity and bioactivity of actinomycetes from marine sediments of the Yellow Sea

    NASA Astrophysics Data System (ADS)

    Zhang, Shumin; Ye, Liang; Tang, Xuexi

    2012-03-01

    Among the 116 actinomycetes collected from marine sediments of the Yellow Sea, 56 grew slowly and appeared after 2-3 weeks of incubation. Among the 56 strains, only 3 required seawater (SW) for growth, and 21 grew well in the medium prepared with SW rather than distilled water (DW), while the remaining 32 grew well either with SW or with DW. Six representatives with different morphological characteristics, including 1 SW-requiring strain and 5 well-growing with SW strains, were selected for phylogenetic analysis based on 16S rRNA gene. Two strains belong to Micrococcaceae and Nocardiopsaceae respectively. The other 4 strains belong to the family of Streptomycetaceae. In the analyzed 6 strains, one was related to Nocardiopsis spp. and the other three were related to Streptomyces spp., representing new taxa. Bioactivity testing of fermentation products from 3 SW-requiring strains and 21 well-growing with SW strains revealed that 17 strains possessed remarkable activities against gram-positive pathogen or/and tumor cells, suggesting that they were prolific resources for natural drug discovery.

  3. RobOKoD: microbial strain design for (over)production of target compounds

    PubMed Central

    Stanford, Natalie J.; Millard, Pierre; Swainston, Neil

    2015-01-01

    Sustainable production of target compounds such as biofuels and high-value chemicals for pharmaceutical, agrochemical, and chemical industries is becoming an increasing priority given their current dependency upon diminishing petrochemical resources. Designing these strains is difficult, with current methods focusing primarily on knocking-out genes, dismissing other vital steps of strain design including the overexpression and dampening of genes. The design predictions from current methods also do not translate well-into successful strains in the laboratory. Here, we introduce RobOKoD (Robust, Overexpression, Knockout and Dampening), a method for predicting strain designs for overproduction of targets. The method uses flux variability analysis to profile each reaction within the system under differing production percentages of target-compound and biomass. Using these profiles, reactions are identified as potential knockout, overexpression, or dampening targets. The identified reactions are ranked according to their suitability, providing flexibility in strain design for users. The software was tested by designing a butanol-producing Escherichia coli strain, and was compared against the popular OptKnock and RobustKnock methods. RobOKoD shows favorable design predictions, when predictions from these methods are compared to a successful butanol-producing experimentally-validated strain. Overall RobOKoD provides users with rankings of predicted beneficial genetic interventions with which to support optimized strain design. PMID:25853130

  4. Antimicrobial potential of Halophilic actinomycetes against multi drug resistant (MDR) ventilator associated pneumonia causing bacterial pathogens.

    PubMed

    Aslam, Sana; Sajid, Imran

    2016-03-01

    A collection of forty halophilic actinomycetes isolated from water and mud samples of the saline lake at Kalar Kahar, salt range, Pakistan, was screened to investigate their antimicrobial potential against multi drug resistant (MDR) ventilator associated pneumonia causing bacterial pathogens. The isolates exhibited significant tolerance to alkaline conditions and grew well at pH 9-11. The taxonomic status of the isolated strains was determined by morphological, biochemical and physiological characterization and by 16s rRNA gene sequencing. The results revealed that majority of the isolates (90%) belong to the genus Streptomyces. Most of the isolates exhibited remarkable antimicrobial activity up to 20mm zone of inhibition against MDR ventilator associated pneumonia causing bacteria including Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris, Klebsiella pneumoniae, Escherichia coli, Enterobacter and Acinetobacter spp. Additionally the isolates showed moderate to high cytotoxicity in the range of 40 to 80% larval mortality against Artemia salina in a micro well cytotoxicity assay. The chemical screening or the so called metabolic fingerprinting of the methanolic extracts of each isolate, by thin layer chromatography (TLC) using various staining reagents and by high performance liquid chromatography (HPLC-UV), indicated an impressive diversity of the compounds produced by these strains. The study reveals that these halophilic actinomycetes are a promising source of bioactive compounds. The preparative scale fermentation, isolation, purification and structure elucidation of the compounds produced by them may yield novel antimicrobial or chemotherapeutic agents. PMID:27087086

  5. Activation and Products of the Cryptic Secondary Metabolite Biosynthetic Gene Clusters by Rifampin Resistance (rpoB) Mutations in Actinomycetes

    PubMed Central

    Tanaka, Yukinori; Kasahara, Ken; Hirose, Yutaka; Murakami, Kiriko; Kugimiya, Rie

    2013-01-01

    A subset of rifampin resistance (rpoB) mutations result in the overproduction of antibiotics in various actinomycetes, including Streptomyces, Saccharopolyspora, and Amycolatopsis, with H437Y and H437R rpoB mutations effective most frequently. Moreover, the rpoB mutations markedly activate (up to 70-fold at the transcriptional level) the cryptic/silent secondary metabolite biosynthetic gene clusters of these actinomycetes, which are not activated under general stressful conditions, with the exception of treatment with rare earth elements. Analysis of the metabolite profile demonstrated that the rpoB mutants produced many metabolites, which were not detected in the wild-type strains. This approach utilizing rifampin resistance mutations is characterized by its feasibility and potential scalability to high-throughput studies and would be useful to activate and to enhance the yields of metabolites for discovery and biochemical characterization. PMID:23603745

  6. Identification and determination of extracellular phytate-degrading activity in actinomycetes.

    PubMed

    Ghorbani-Nasrabadi, Reza; Greiner, Ralf; Alikhani, Hossein Ali; Hamedi, Javad

    2012-07-01

    In this study 97 soil samples from different soil ecosystems were collected. The initial screening was performed on modified glycerol arginine agar (MGAA) to isolate common actinomycetes and on modified MGA-SE (MMGA-SE) to isolate rare actinomycetes. Sixty-seven isolates potentially producing extracellular phytate-degrading activity were identified. The potential to dephosphorylate phytate was confirmed in liquid culture for 46.3 % of the isolates. 12 strains were selected for a direct determination of their phytate-degrading capacity. The results highlighted that the selected isolates produced extracellular phytate-degrading activity; however their capacity in InsP(6) degradation was different. In addition the fermentation medium had an effect on the extent of phytate degradation. Some enzymatic properties of the phytases from isolate No. 43 and isolate No. 63 were determined after obtaining phytase-enriched samples. The enzymes had maximum phytate-degrading capability at 55 °C and pH 5 (isolate No. 43) and 37 °C and pH 7 (isolates No. 63), respectively. Due to their properties, the phytase of isolate No. 43 behaves like a histidine acid phytase, whereas the phytase of No. 63 showed similar enzymatic properties to the phytase of lily. To our knowledge, the results from this study demonstrated for the first time that actinomycetes produce extracellular phytate-degrading activity. By 16SrRNA sequencing, the more closely studied phytase producers were identified as Streptomyces sp. Isolate No. 43 showed 98 % identity to Streptomyces alboniger and S. venezuelae, while isolate No. 63 exhibited 98 % sequence identity to S. ambofaciens and S. lienomycini. PMID:22806166

  7. Design and application of FBG strain experimental apparatus in high temperature

    NASA Astrophysics Data System (ADS)

    Xia, Zhongcheng; Liu, Yueming; Gao, Xiaoliang

    2014-09-01

    Fiber Bragg Grating (FBG) sensing technology has many applications, and it's widely used in detection of temperature, strain and etc. Now the application of FBG sensor is limited to the temperature below 200°C owing to the so called High Temperature Erasing Phenomenon. Strain detection over 200°C is still an engineering challenge since high temperature has a bad influence on the sensor, testing equipment and test data, etc, thus effective measurement apparatus are needed to ensure the accuracy of the measurement over 200°C, but there are no suitable FBG strain experimental apparatus in high temperature to date. In this paper a high temperature FBG strain experimental apparatus has been designed to detect the strain in high temperature. In order to verify working condition of the high temperature FBG strain, an application of FBG strain sensing experiment was given in this paper. The high temperature FBG strain sensor was installed in the apparatus, the internal temperature of experimental apparatus was controlled from -20 to 300°C accurately, and strain loading was given by the counterweight, then the data was recorded through electrical resistance strain measurement and optical sensing interrogator. Experimental data result shows that the high temperature FBG strain experimental apparatus can work properly over 200°C. The design of the high temperature FBG strain experimental apparatus are demonstrated suitable for high temperature strain gauges and FBG strain sensors , etc, which can work under the temperature of -20 ~ 300°C, the strain of -1500 ~ +1500μepsilon and the wavelength resolution of 1pm.

  8. Pectinolytic Enzymes from Actinomycetes for the Degumming of Ramie Bast Fibers

    PubMed Central

    Brühlmann, Fredi; Kim, Kwi Suk; Zimmerman, Wolfgang; Fiechter, Armin

    1994-01-01

    Actinomycetes isolated from 10 different soil and compost samples were screened for production of pectinolytic enzyme activities when grown on pectin-containing solid and liquid media. Pectinolytic enzymes, detected by using plate diffusion tests with a medium containing ramie (Boehmeria nivea) plant material as the sole carbon source, were mainly pectate lyases, but low activities of pectinesterases were also observed. Polygalacturonases and polymethylgalacturonases were not produced. Multiple forms of pectate lyases were detected in the culture supernatants of some of the strains by using the zymogram technique of isoelectric focusing gels. Xylanolytic and cellulolytic activities were always found to be associated with pectinolytic activities. None of the pectinolytic enzymes were produced in a medium with glucose as the sole carbon source. Treatment of ramie bast fibers with crude enzyme preparations from a selection of strains showed a good correlation between the pectate lyase activity applied and the degumming effect, resulting in good separation of the bast fibers. Images PMID:16349296

  9. Nonomuraea aegyptia sp. nov., a novel actinomycete isolated from a sand dune.

    PubMed

    Hozzein, Wael N; Goodfellow, Michael

    2007-08-01

    The taxonomic position of an unknown actinomycete isolated from a sand dune soil sample collected at Borg El-Arab in Egypt was established using a combination of genotypic and phenotypic data. Isolate S136(T) had chemotaxonomic and morphological properties consistent with its classification in the genus Nonomuraea and formed a distinct phyletic line in the Nonomuraea 16S rRNA gene tree. It was most closely related to the type strains of Nonomuraea helvata, Nonomuraea kuesteri and Nonomuraea turkmeniaca, sharing 16S rRNA gene similarities with these species of 97.1, 97.2 and 97.3%, respectively. The organism was distinguished from representatives of validly described Nonomuraea species using a range of phenotypic properties. It is apparent that the isolate belongs to a novel Nonomuraea species. The name proposed for this taxon is Nonomuraea aegyptia sp. nov., the type strain is S136(T) (=CGMCC 4.2054(T) = DSM 45082(T)). PMID:17318331

  10. [Ecophysiological Characteristics of actinomycetes of desert soils of Mongolia].

    PubMed

    Zenova, G M; Kozhevin, P A; Manucharova, N A; Lubsanova, D A; Dubrova, M S

    2014-01-01

    It is shown that the actinomycete complex in steppe-desert light brown salty soil of desert steppes of Mongolia is represented by the genera Streptomyces and Micromonospora. The species diversity of the genus Streptomyces, which dominates the complex, decreases with increasing osmolarity of the medium. The influence of environmental factors--temperature and osmolarity of medium--on the development of metabolically active members of the phylum Actinobacteria in the domain Bacteria of the prokaryotic microbial soil community was established. The proportion of metabolically active bacteria belonging to Actinobacteria increases with increasing osmolarity and incubation temperature of soil. The dominance of the filamentous metabolically active members of the phylum Actinobacteria over the unicellular organisms was shown. The halotolerant actinomycetes isolated from the steppe-desert soils were alkalotolerant, xerophilic, and thermotolerant and exhibited antimicrobial activity with respect to Gram-positive bacteria and actinomycetes. PMID:25731035

  11. Characterization of a Truncated Lipoarabinomannan from the Actinomycete Turicella otitidis

    PubMed Central

    Gilleron, Martine; Garton, Natalie J.; Nigou, Jérôme; Brando, Thérèse; Puzo, Germain; Sutcliffe, Iain C.

    2005-01-01

    Lipoarabinomannan (LAM) lipoglycans have been characterized from a range of mycolic acid-containing actinomycetes and from the amycolate actinomycete Amycolatopsis sulphurea. To further understand the structural diversity of this family, we have characterized the lipoglycan of the otic commensal Turicella otitidis. T. otitidis LAM (TotLAM) has been determined to consist of a mannosyl phosphatidylinositol anchor unit carrying an (α 1→6)-linked mannan core and substituted with terminal-arabinosyl branches. Thus, TotLAM has a novel truncated LAM structure. Using the human monocytic THP-1 cell line, it was found that TotLAM exhibited only minimal ability to induce tumor necrosis factor alpha. These findings contribute further to our understanding of actinomycete LAM diversity and allow further speculation as to the correlation between LAM structure and the immunomodulatory activities of these lipoglycans. PMID:15659663

  12. Herbicidal agents from actinomycetes against selected crop plants and weeds.

    PubMed

    Dhanasekaran, Dharumadurai; Thajuddin, Nooruddin; Panneerselvam, Annamalai

    2010-04-01

    About 64 total actinomycetes were isolated from various coastal soils. Sixteen actinomycete isolates were screened for herbicidal principles. Out of these, five potent isolates were selected for characterisation and identification. Based on their morphological, biochemical and physiological characteristics, the actinomycete isolates were identified as Glyomyces, Saccharomonospra and Streptomyces sp. The Streptomycetes isolates were tested for herbicidal principles by germination inhibition assay. About 10 crop seeds were tested for herbicidal activity with Streptomycetes isolates. The crop seeds did not show growth inhibition. Four weed seeds were tested for herbicidal activity with Streptomyces isolates. Streptomyces inhibits the growth of Echinochilora crusgalli, but it could not inhibit the growth of Echinochilora colonum, Parthenium sp., or Ageratum conizoites. The present study concludes that Streptomyces isolates will be a bioherbicide against E. crusgalli. Further study is required to confirm the activity of Streptomyces isolates against E. crusgalli under field conditions. PMID:20182949

  13. Actinomycetes from Eucalyptus and their biological activities for controlling Eucalyptus leaf and shoot blight.

    PubMed

    Himaman, Winanda; Thamchaipenet, Arinthip; Pathom-Aree, Wasu; Duangmal, Kannika

    2016-01-01

    In Thailand, Eucalyptus plantations rapidly expand across the country. Leaf and shoot blight caused by Cryptosporiopsis eucalypti, Cylindrocladium sp. and Teratosphaeria destructans is a serious disease in Eucalyptus plantations. In this study, a total of 477 actinomycete strains were successfully isolated from roots and rhizosphere soil of Eucalyptus. Four hundred and thirty nine isolates were classified as streptomycetes and 38 isolates were non-streptomycetes. Among these isolates, 272 (57.0%), 118 (24.7%) and 241 (50.5%) isolates were antagonistic to Cryptosporiopsis eucalypti, Cylindrocladium sp. and Teratosphaeria destructans, respectively. All isolates were tested for their abilities to produce siderophores, indole acetic acid (IAA) and solubilise phosphate. Most isolates (464, 97.3%) produced siderophores. The majority of isolates (345, 72.3%) solubilised phosphate. In addition, almost half of these isolates (237, 49.7%) produced indole acetic acid. Strain EUSKR2S82 which showed the strongest inhibitory effect against all tested fungi with plant growth promoting ability was selected to test with Eucalyptus. This strain could colonize plant roots and increase Eucalyptus roots length. In a detached leaves bioassay, the disease severity of EUSKR2S82-inoculated Eucalyptus leaves was only 30% compared to 95% in the control treatment. The 16S rRNA gene sequence analysis revealed that the strain EUSKR2S82 was related to Streptomyces ramulosus NRRL-B 2714(T) (99.44% similarity). Identification of non-streptomycete isolates using 16S rRNA gene sequences classified them into 9 genera: Actinoallomurus, Actinomadura, Amycolatopsis, Cryptosporangium, Microbispora, Micromonospora, Nocardia, Nonomuraea and Pseudonocardia. It is evident that Eucalyptus tree harbored several genera of actinomycetes. The selected isolate, EUSKR2S82 showed potential as a candidate for biocontrol agent of leaf and shoot blight of Eucalyptus and to promote growth. PMID:27296961

  14. Cultivable actinomycetes from rhizosphere of birch (Betula pendula) growing on a coal mine dump in Silets, Ukraine.

    PubMed

    Ostash, Bohdan; Gren, Tetiana; Hrubskyy, Yaroslav; Tistechok, Stepan; Beshley, Stepan; Baranov, Volodymyr; Fedorenko, Victor

    2014-08-01

    Five actinomycete strains were isolated from the rhizosphere of birch, one of a few native tree forms capable of thriving on the upper level of a coal mine dump near the village of Silets (Lvivska region, Ukraine). No such strains were isolated from surrounding gangue, or from nearby grass Calamagrostis epigeios. Using 16S rDNA sequencing and analysis of cell wall aminoacids, four of these strains were shown to belong to genus Streptomyces and one to be Amycolatopsis. The isolates were able to produce siderophores and antibacterial compounds. In comparison to the reference strain Streptomyces coelicolor M145, certain rhizospheric isolates displayed somewhat increased survival in the presence of copper, iron(III), or chromium(VI) salts. The Amycolatopsis isolate was also shown to accumulate significant quantities of heavy metals from waste extracts. Possible roles of the described strains in coal mine dump ecology are discussed. PMID:23686352

  15. Screening of Marine Actinomycetes from Segara Anakan for Natural Pigment and Hydrolytic Activities

    NASA Astrophysics Data System (ADS)

    Asnani, A.; Ryandini, D.; Suwandri

    2016-02-01

    Marine actinomycetes have become sources of great interest to natural product chemistry due to their new chemical entities and bioactive metabolites. Since April 2010, we have screened actinobacteria from five sites that represent different ecosystems of Segara Anakan lagoon. In this present study we focus on specific isolates, K-2C which covers 1) actinomycetes identification based on morphology observation and 16S rRNA gene; 2) fermentation and isolation of pigment; 3) structure determination of pigment; and 4) hydrolytic enzymes characterization; Methodologies relevant to the studies were implemented accordingly. The results indicated that K-2C was likely Streptomyces fradiae strain RSU15, and the best fermentation medium should contain starch and casein with 21 days of incubation. The isolate has extracellular as well as intracellular pigments. Isolated pigments gave purple color with λmax of 529.00 nm. The pigment was structurally characterized. Interestingly, Streptomyces K-2C was able to produce potential hydrolytic enzymes such as amylase, cellulase, protease, lipase, urease, and nitrate reductase.

  16. Endophytic Actinomycetes: A Novel Source of Potential Acyl Homoserine Lactone Degrading Enzymes

    PubMed Central

    Chankhamhaengdecha, Surang; Hongvijit, Suphatra; Srichaisupakit, Akkaraphol; Charnchai, Pattra; Panbangred, Watanalai

    2013-01-01

    Several Gram-negative pathogenic bacteria employ N-acyl-L-homoserine lactone (HSL) quorum sensing (QS) system to control their virulence traits. Degradation of acyl-HSL signal molecules by quorum quenching enzyme (QQE) results in a loss of pathogenicity in QS-dependent organisms. The QQE activity of actinomycetes in rhizospheric soil and inside plant tissue was explored in order to obtain novel strains with high HSL-degrading activity. Among 344 rhizospheric and 132 endophytic isolates, 127 (36.9%) and 68 (51.5%) of them, respectively, possessed the QQE activity. The highest HSL-degrading activity was at 151.30 ± 3.1 nmole/h/mL from an endophytic actinomycetes isolate, LPC029. The isolate was identified as Streptomyces based on 16S  rRNA gene sequence similarity. The QQE from LPC029 revealed HSL-acylase activity that was able to cleave an amide bond of acyl-side chain in HSL substrate as determined by HPLC. LPC029 HSL-acylase showed broad substrate specificity from C6- to C12-HSL in which C10HSL is the most favorable substrate for this enzyme. In an in vitro pathogenicity assay, the partially purified HSL-acylase efficiently suppressed soft rot of potato caused by Pectobacterium carotovorum ssp. carotovorum as demonstrated. To our knowledge, this is the first report of HSL-acylase activity derived from an endophytic Streptomyces. PMID:23484156

  17. Development of actinomycetes in brown semidesert soil under low water pressure

    NASA Astrophysics Data System (ADS)

    Zvyagintsev, D. G.; Zenova, G. M.; Sudnitsyn, I. I.; Gracheva, T. A.; Lapygina, E. E.; Napol'skaya, K. R.; Sydnitsyna, A. E.

    2012-07-01

    Under laboratory conditions, the spores of a xerotolerant Streptomyces odorifera strain germinated in brown semidesert soil even at extremely low soil water pressure ( P = -96.4 MPa, -964 atm, a w 0.50); the plantlets increased in length and formed mycelium, on which a new generation of spores was produced (a complete development cycle of the actinomycetes—from a spore to the formation of new spores—passed). The duration of the first cycles of the actinomycetes' development varied from 13 days at P = -27 atm to 57 days at P = -964 atm and was directly proportional to the absolute value of the soil water pressure ( P). In the first cycles of the actinomycetes' development, the rate of increase of the concentration of the germinated spores and mycelium, as well as the logarithms of the mycelium-to-germinated spore concentration ratios, was inversely proportional to the logarithm of P. These relationships indicated that the energy state of the water determined its availability to soil biota and, hence, the activity of its physiological and biochemical processes.

  18. Study of the cellulases produced by three mesophilic actinomycetes grown on bagasse as substrate

    SciTech Connect

    Van Zyl, W.H.

    1985-09-01

    The cellulases that strains of Streptomyces albogrisolus, S. nitrosporeus, and Micromonospora melanosporea produce when grown on untreated ballmilled bagasse were investigated. Optimum conditions for extracellular cellulase production and activity were determined to be growth at pH 6.7-7.4 and 25-35 degrees C for 4-5 days and assay at pH 5.0-6.0 and 45-55 degrees C, respectively. The endoglucanases were thermally stable at 50 degrees C, but the Avicelases had a half-life of approximately 24 hours at this temperature. Nearly half of the endoglucanases and almost all of the Avicelases were absorbed on ballmilled bagasse after 15 minutes incubation at 50 degrees C. The ..beta..-glucosidases were found to be mainly intracellular or cell wall bound. These mesophilic actinomycetes concomitantly produced xylanases and ..beta..-xylosidases with cellulases that, apart from cellobiose and glucose, also release xylose from bagasse. This feature may be advantageous in the commercial application of the enzymes of mesophilic actinomycetes for the saccharification of natural cellulosic substrates.

  19. Streptomyces synnematoformans sp. nov., a novel actinomycete isolated from a sand dune soil in Egypt.

    PubMed

    Hozzein, Wael N; Goodfellow, Michael

    2007-09-01

    A polyphasic taxonomic study was undertaken to establish the status of a novel actinomycete, strain S155(T), isolated from a sand dune soil in Egypt. The organism formed characteristic synnemata-like structures and exhibited chemical and morphological features consistent with its classification in the genus Streptomyces. An almost-complete 16S rRNA gene sequence of the isolate was compared with corresponding sequences of representative streptomycetes. The 16S rRNA gene sequence data supported the assignment of the strain to the genus Streptomyces and showed that it formed a distinct phyletic line; the organism was most similar to the type strains of Streptomyces ruber (97.0 %), Streptomyces rubiginosus (97.0 %), Streptomyces roseiscleroticus (96.9 %) and Streptomyces thermoalcalitolerans (97.1 %). It was readily distinguished from the type strains of these species using a combination of phenotypic properties. On the basis of these results, strain S155(T) (=CGMCC 4.2055(T) =DSM 41902(T)) is proposed as the type strain of the novel species Streptomyces synnematoformans sp. nov. PMID:17766864

  20. Materials design and processings for industrial high-strain-rate superplastic forming

    SciTech Connect

    Hosokawa, H.; Higashi, K.

    2000-07-01

    The optimum materials design in microstructural control could be developed for the high-strain-rate superplastic materials in the industrial scale. In the present work, it is reported that the high-performance-engine pistons with near-net-shape can be fabricated by the superplastic forging technology in the high-strain-rate superplastic PM Al-Si based alloy, which is produced by using this optimum materials design.

  1. Design of an enhanced sensitivity FBG strain sensor and application in highway bridge engineering

    NASA Astrophysics Data System (ADS)

    Li, Litong; Zhang, Dongsheng; Liu, Hui; Guo, Yongxing; Zhu, Fangdong

    2014-06-01

    The theoretical design method of enhanced sensitivity fiber grating (FBG) strain sensors was given, and moreover high qualified strain sensors were developed and fabricated, whose sensing properties were good for practical applications. The strain sensor with cylindrical shell encapsulation contained three tubular structures, due to the uneven surface structure, in the area of the strain concentration, improving the sensitivity. It could achieve the embedment strain measurement and surface measurement and had the advantages of the easy installation. The good agreement was obtained between the measurements and theoretical simulation results. After each calibration test, twenty-four FBG strain sensors and six FBG temperature compensation sensors have been installed on the undersurface of the box girder of Diaoshuiyan bridge in Yongtaiwen highway. Finally, we built up a long-term structure health system for the highway bridge.

  2. A novel taxonomic marker that discriminates between morphologically complex actinomycetes

    PubMed Central

    Girard, Geneviève; Traag, Bjørn A.; Sangal, Vartul; Mascini, Nadine; Hoskisson, Paul A.; Goodfellow, Michael; van Wezel, Gilles P.

    2013-01-01

    In the era when large whole genome bacterial datasets are generated routinely, rapid and accurate molecular systematics is becoming increasingly important. However, 16S ribosomal RNA sequencing does not always offer sufficient resolution to discriminate between closely related genera. The SsgA-like proteins are developmental regulatory proteins in sporulating actinomycetes, whereby SsgB actively recruits FtsZ during sporulation-specific cell division. Here, we present a novel method to classify actinomycetes, based on the extraordinary way the SsgA and SsgB proteins are conserved. The almost complete conservation of the SsgB amino acid (aa) sequence between members of the same genus and its high divergence between even closely related genera provides high-quality data for the classification of morphologically complex actinomycetes. Our analysis validates Kitasatospora as a sister genus to Streptomyces in the family Streptomycetaceae and suggests that Micromonospora, Salinispora and Verrucosispora may represent different clades of the same genus. It is also apparent that the aa sequence of SsgA is an accurate determinant for the ability of streptomycetes to produce submerged spores, dividing the phylogenetic tree of streptomycetes into liquid-culture sporulation and no liquid-culture sporulation branches. A new phylogenetic tree of industrially relevant actinomycetes is presented and compared with that based on 16S rRNA sequences. PMID:24153003

  3. The medically important aerobic actinomycetes: epidemiology and microbiology.

    PubMed Central

    McNeil, M M; Brown, J M

    1994-01-01

    The aerobic actinomycetes are soil-inhabiting microorganisms that occur worldwide. In 1888, Nocard first recognized the pathogenic potential of this group of microorganisms. Since then, several aerobic actinomycetes have been a major source of interest for the commercial drug industry and have proved to be extremely useful microorganisms for producing novel antimicrobial agents. They have also been well known as potential veterinary pathogens affecting many different animal species. The medically important aerobic actinomycetes may cause significant morbidity and mortality, in particular in highly susceptible severely immunocompromised patients, including transplant recipients and patients infected with human immunodeficiency virus. However, the diagnosis of these infections may be difficult, and effective antimicrobial therapy may be complicated by antimicrobial resistance. The taxonomy of these microorganisms has been problematic. In recent revisions of their classification, new pathogenic species have been recognized. The development of additional and more reliable diagnostic tests and of a standardized method for antimicrobial susceptibility testing and the application of molecular techniques for the diagnosis and subtyping of these microorganisms are needed to better diagnose and treat infected patients and to identify effective control measures for these unusual pathogens. We review the epidemiology and microbiology of the major medically important aerobic actinomycetes. Images PMID:7923055

  4. A Web-Based Platform for Designing Vaccines against Existing and Emerging Strains of Mycobacterium tuberculosis

    PubMed Central

    Dhanda, Sandeep Kumar; Vir, Pooja; Singla, Deepak; Gupta, Sudheer; Kumar, Shailesh

    2016-01-01

    Development of an effective vaccine against drug-resistant Mycobacterium tuberculosis (Mtb) is crucial for saving millions of premature deaths every year due to tuberculosis. This paper describes a web portal developed for assisting researchers in designing vaccines against emerging Mtb strains using traditional and modern approaches. Firstly, we annotated 59 genomes of Mycobacterium species to understand similarity/dissimilarity between tuberculoid, non-tuberculoid and vaccine strains at genome level. Secondly, antigen-based vaccine candidates have been predicted in each Mtb strain. Thirdly, epitopes-based vaccine candidates were predicted/discovered in above antigen-based vaccine candidates that can stimulate all arms of immune system. Finally, a database of predicted vaccine candidates at epitopes as well at antigen level has been developed for above strains. In order to design vaccine against a newly sequenced genome of Mtb strain, server integrates three modules for identification of strain-, antigen-, epitope-specific vaccine candidates. We observed that 103522 unique peptides (9mers) had the potential to induce an antibody response and/or promiscuous binder to MHC alleles and/or have the capability to stimulate T lymphocytes. In summary, this web-portal will be useful for researchers working on designing vaccines against Mtb including drug-resistant strains. Availability: The database is available freely at http://crdd.osdd.net/raghava/mtbveb/. PMID:27096425

  5. Modeling, design, fabrication, and testing of a fiber Bragg grating strain sensor array

    NASA Astrophysics Data System (ADS)

    Abdi, Abdeq M.; Suzuki, Shigeru; Schülzgen, Axel; Kost, Alan R.

    2007-05-01

    The modeling, design, simulation, fabrication, calibration, and testing of a three-element, 15.3 cm fiber Bragg grating strain sensor array with the coherent optical frequency domain reflectometry (C-OFDR) interrogation technique are demonstrated. The fiber Bragg grating array (FBGA) is initially simulated using in-house software that incorporates transfer matrices. Compared to the previous techniques used, the transfer matrix method allows a systemwide approach to modeling the FBGA-C-OFDR system. Once designed and simulated, the FBGA system design is then imprinted into the core of a boron-germanium codoped photosensitive fiber using the phase mask technique. A fiber optic Fabry-Perot interferometric (FPI) strain gauge calibrator is then used to determine the strain gauge factor of a single fiber Bragg grating (FBG), and the results are used on the FBGA. The FPI strain gauge calibrator offers nondestructive testing of the FBG. To test the system, the FBGA is then attached to a 75 cm cantilever beam and interrogated using an incremental tunable laser. Electric strain gauges (ESGs) are then used to independently verify the strain measurements with the FBGA at various displacements of the cantilever beam. The results show that the peak strain error is 18% with respect to ESG results. In addition, good agreement is shown between the simulation and the experimental results.

  6. Actinoallomurus bryophytorum sp. nov., an endophytic actinomycete isolated from moss (Bryophyta).

    PubMed

    Li, Chuang; Wang, Haiyan; Jin, Pinjiao; Zheng, Weijia; Chu, Liyang; Liu, Chongxi; Li, Jiansong; Xiang, Wensheng; Wang, Xiangjing

    2015-08-01

    A novel endophytic actinomycete, strain NEAU-TX1-15(T), was isolated from moss, collected from Wuchang, Heilongjiang province, north China. A polyphasic taxonomic study was carried out to establish the status of strain NEAU-TX1-15(T). Morphological and chemotaxonomic properties of strain NEAU-TX1-15(T) are consistent with the description of the genus Actinoallomurus. Strain NEAU-TX1-15(T) was observed to form short spiral or looped spore chains on aerial hyphae. The cell wall peptidoglycan was found to contain lysine and meso-diaminopimelic acid. The major menaquinones were identified as MK-9(H6) and MK-9(H8). The only phospholipid identified was phosphatidylglycerol. The major fatty acid was identified as iso-C16:0. Analysis of the 16S rRNA gene sequence supports the assignment of the novel strain to the genus Actinoallomurus, as it exhibits 99.2 % gene sequence similarity to that of Actinoallomurus yoronensis NBRC 103686(T). However, the low level of DNA-DNA relatedness allowed the strain to be differentiated from its close relative. Moreover, strain NEAU-TX1-15(T) could also be differentiated from A. yoronensis NBRC 103686(T) and other Actinoallomurus species showing high 16S rRNA gene sequence similarity (>98.0 %) by cultural and physiological characteristics. Therefore, the combination of phenotypic and chemotaxonomic data, and the DNA-DNA hybridization value, indicated that strain NEAU-TX1-15(T) represents a novel species of the genus Actinoallomurus for which the name Actinoallomurus bryophytorum sp. nov. is proposed. The type strain is NEAU-TX1-15(T) (=CGMCC 4.7200(T) = JCM 30340(T)). PMID:26033369

  7. Cyclic material properties at high strain ranges beyond the standard design codes

    NASA Astrophysics Data System (ADS)

    Maile, Karl; Bothe, Klaus; Blind, Dieter; Vazoukis, Georg

    1992-07-01

    Low cycle fatigue tests were performed at characteristic temperatures on materials employed in nuclear piping systems. The influence of strain rate, temperature, surface roughness, notches and welding on the number of cycles to crack initiation and failure were investigated in the high strain range regime. The crack initiation does not depend significantly on the strain rate, the surface conditions and the temperature. The fatigue endurance of notched specimens cannot be satisfactorily compared with that of smooth specimens. The influence of welding depends on the material. The results of the smooth specimens lie above the design curves of TRD, KTA and ASME code.

  8. Strain response of stretchable micro-electrodes: Controlling sensitivity with serpentine designs and encapsulation

    SciTech Connect

    Gutruf, Philipp; Walia, Sumeet; Nur Ali, Md; Sriram, Sharath E-mail: madhu.bhaskaran@gmail.com; Bhaskaran, Madhu E-mail: madhu.bhaskaran@gmail.com

    2014-01-13

    The functionality of flexible electronics relies on stable performance of thin film micro-electrodes. This letter investigates the behavior of gold thin films on polyimide, a prevalent combination in flexible devices. The dynamic behavior of gold micro-electrodes has been studied by subjecting them to stress while monitoring their resistance in situ. The shape of the electrodes was systematically varied to examine resistive strain sensitivity, while an additional encapsulation was applied to characterize multilayer behavior. The realized designs show remarkable tolerance to repetitive strain, demonstrating that curvature and encapsulation are excellent approaches for minimizing resistive strain sensitivity to enable durable flexible electronics.

  9. Design and Testing of the Strain Transducer for Measuring Deformations of Pipelines Operating in the Mining-deformable Ground Environment

    NASA Astrophysics Data System (ADS)

    Gawedzki, Waclaw; Tarnowski, Jerzy

    2015-10-01

    Design and laboratory test results of the strain transducer intended for monitoring and assessing stress states of pipelines sited in mining areas are presented in this paper. This transducer allows measuring strains of pipelines subjected to external forces - being the mining operations effect. Pipeline strains can have a direct influence on a tightness loss and penetration of the transported fluid into the environment. The original strain gauge transducer was proposed for performing measurements of strains. It allows measuring circumferential strains and determining the value and direction of the main longitudinal strain. This strain is determined on the basis of measuring component longitudinal strains originating from axial forces and the resultant bending moment. The main purpose of investigations was the experimental verification of the possibility of applying the strain transducer for measuring strains of polyethylene pipelines. The obtained results of the transducer subjected to influences of tensile and compression forces are presented and tests of relaxation properties of polyethylene are performed.

  10. Nocardiopsis arabia sp. nov., a halotolerant actinomycete isolated from a sand-dune soil.

    PubMed

    Hozzein, Wael N; Goodfellow, Michael

    2008-11-01

    The taxonomic status of an unknown actinomycete isolated from a sand-dune soil was established using a polyphasic approach. Isolate S186(T) had chemotaxonomic and morphological properties consistent with its classification in the genus Nocardiopsis, grew on agar plates at NaCl concentrations of up to 15 % (w/v) and formed a distinct phyletic line in the Nocardiopsis 16S rRNA gene sequence tree. Its closest phylogenetic neighbours were Nocardiopsis chromatogenes, Nocardiopsis composta, Nocardiopsis gilva and Nocardiopsis trehalosi, with sequence similarity to the various type strains of 96.9 %, but it was readily distinguished from the type strains of these and related species using a range of phenotypic properties. It is apparent from the genotypic and phenotypic data that strain S186(T) belongs to a novel species of the genus Nocardiopsis, for which the name Nocardiopsis arabia sp. nov. is proposed. The type strain is S186(T) (=CGMCC 4.2057(T) =DSM 45083(T)). PMID:18984686

  11. Effect of nickel titanium file design on the root surface strain and apical microcracks.

    PubMed

    Jamleh, Ahmed; Adorno, Carlos G; Ebihara, Arata; Suda, Hideaki

    2016-04-01

    The aim of this study was to determine the effect of nickel titanium file design on the root surface strain generated and apical microcracks caused during canal shaping. Thirty-three mandibular incisors were distributed into LightSpeed X, FlexMaster and a control group. A strain gauge was fixed apically on the proximal root surface to determine the maximum strain during canal shaping. Except for the control group, all root canals were enlarged to size 50. Images were taken after removing the apical 1 and 2 mm of the root end. Mean maximum strain values and presence of microcracks were statistically compared using the t-test and chi-square test, respectively. During canal shaping, the strain increased cumulatively with mean maximum strains of 808.2 ± 228.8 and 525.1 ± 168.9 microstrain in LightSpeed X and FlexMaster, respectively (P = 0.004). Both systems caused comparable microcracks. Although LightSpeed X produced higher maximum strain, no difference in microcrack development was found between both systems. PMID:26420627

  12. Human papilloma virus strain detection utilising custom-designed oligonucleotide microarrays.

    PubMed

    Ayers, Duncan; Platt, Mark; Javad, Farzad; Day, Philip J R

    2011-01-01

    Within the past 15 years, the utilisation of microarray technology for the detection of specific pathogen strains has increased rapidly. Presently, it is possible to simply purchase a pre-manufactured "off the shelf " oligonucleotide microarray bearing a wide variety of known signature DNA sequences previously identified in the organism being studied. Consequently, a hybridisation analysis may be used to pinpoint which strain/s is present in any given clinical sample. However, there exists a problem if the study necessitates the identification of novel sequences which are not represented in commercially available microarray chips. Ideally, such investigations require an in situ oligonucleotide microarray platform with the capacity to synthesise microarrays bearing probe sequences designed solely by the researcher. This chapter will focus on the employment of the Combimatrix® B3 CustomArray™ for the synthesis of reusable, bespoke microarrays for the purpose of discerning multiple Human Papilloma Virus strains. PMID:20938834

  13. Design, Evaluation and Experimental Effort Toward Development of a High Strain Composite Wing for Navy Aircraft

    NASA Technical Reports Server (NTRS)

    Bruno, Joseph; Libeskind, Mark

    1990-01-01

    This design development effort addressed significant technical issues concerning the use and benefits of high strain composite wing structures (Epsilon(sub ult) = 6000 micro-in/in) for future Navy aircraft. These issues were concerned primarily with the structural integrity and durability of the innovative design concepts and manufacturing techniques which permitted a 50 percent increase in design ultimate strain level (while maintaining the same fiber/resin system) as well as damage tolerance and survivability requirements. An extensive test effort consisting of a progressive series of coupon and major element tests was an integral part of this development effort, and culminated in the design, fabrication and test of a major full-scale wing box component. The successful completion of the tests demonstrated the structural integrity, durability and benefits of the design. Low energy impact testing followed by fatigue cycling verified the damage tolerance concepts incorporated within the structure. Finally, live fire ballistic testing confirmed the survivability of the design. The potential benefits of combining newer/emerging composite materials and new or previously developed high strain wing design to maximize structural efficiency and reduce fabrication costs was the subject of subsequent preliminary design and experimental evaluation effort.

  14. Actinopolyspora righensis sp. nov., a novel halophilic actinomycete isolated from Saharan soil in Algeria.

    PubMed

    Meklat, Atika; Bouras, Noureddine; Zitouni, Abdelghani; Mathieu, Florence; Lebrihi, Ahmed; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter; Sabaou, Nasserdine

    2013-09-01

    A novel halophilic actinomycete strain, H23(T), was isolated from a Saharan soil sample collected in Djamâa (Oued Righ region), El-Oued province, South Algeria. Strain H23(T) was identified as a member of the genus Actinopolyspora by a polyphasic approach. Phylogenetic analysis showed that strain H23(T) had 16S rRNA gene sequence similarities ranging from 97.8 % (Actinopolyspora xinjiangensis TRM 40136(T)) to 94.8 % (Actinopolyspora mortivallis DSM 44261(T)). The strain grew optimally at pH 6.0-7.0, 28-32 °C and in the presence of 15-25 % (w/v) NaCl. The substrate mycelium was well developed and fragmented with age. The aerial mycelium produced long, straight or flexuous spore chains with non-motile, smooth-surfaced and rod-shaped spores. Strain H23(T) had MK-10 (H4) and MK-9 (H4) as the predominant menaquinones. The whole micro-organism hydrolysates mainly consisted of meso-diaminopimelic acid, galactose and arabinose. The diagnostic phospholipid detected was phosphatidylcholine. The major cellular fatty acids were anteiso-C17:0 (37.4 %), iso-C17:0 (14.8 %), iso-C15:0 (14.2 %), and iso-C16:0 (13.9 %). The genotypic and phenotypic data show that the strain represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora righensis sp. nov. is proposed, with the type strain H23(T) (=DSM 45501(T) = CCUG 63368(T) = MTCC 11562(T)). PMID:23754661

  15. Actinomycetes in Karstic caves of northern Spain (Altamira and Tito Bustillo).

    PubMed

    Groth, I; Vettermann, R; Schuetze, B; Schumann, P; Saiz-Jimenez, C

    1999-05-01

    A variety of isolation procedures were carried out to study the involvement of bacteria in the colonisation and biodeterioration of Spanish caves with paleolithic rock art (Altamira and Tito Bustillo). The applied techniques mainly aimed to isolate heterotrophic bacteria such as streptomycetes, nocardioform and coryneform actinomycetes, and other gram-positive and gram-negative bacteria. The results demonstrated that actinomycetes were the most abundant gram-positive bacteria in the caves. Actinomycetes revealed a great taxonomic diversity with the predominant isolates belonging to the genus Streptomyces. Members of the genera Nocardia, Rhodococcus, Nocardioides, Amycolatopsis, Saccharothrix, Brevibacterium, Microbacterium, and coccoid actinomycetes (family Micrococcaceae) were also found. PMID:10353805

  16. The structural-functional organization of thermotolerant complexes of actinomycetes in desert and volcanic soils

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Kurapova, A. I.; Lysenko, A. M.; Zvyagintsev, D. G.

    2009-05-01

    It has been found that the number of thermotolerant actinomycetes in strongly heated soils of deserts and volcanic regions is comparable to or exceeds the number of mesophilic actinomycetes. Among the latter group, streptomyces usually predominate; among thermotolerant actinomycetes, representatives of the Micromonospora, Streptosporangium, Actinomadura, Saccharopolyspora, Microtetraspora, and Microbispora genera are identified. Thermotolerant actinomycetes display the full cycle of their development in these soils. The method of fluorescent in situ hybridization has made it possible to determine that mycelial forms predominate among the metabolically active representatives of Actinobacteria; their portion increases with the rise in the temperature of soil incubation.

  17. CRISPR-Cas9 Based Engineering of Actinomycetal Genomes.

    PubMed

    Tong, Yaojun; Charusanti, Pep; Zhang, Lixin; Weber, Tilmann; Lee, Sang Yup

    2015-09-18

    Bacteria of the order Actinomycetales are one of the most important sources of pharmacologically active and industrially relevant secondary metabolites. Unfortunately, many of them are still recalcitrant to genetic manipulation, which is a bottleneck for systematic metabolic engineering. To facilitate the genetic manipulation of actinomycetes, we developed a highly efficient CRISPR-Cas9 system to delete gene(s) or gene cluster(s), implement precise gene replacements, and reversibly control gene expression in actinomycetes. We demonstrate our system by targeting two genes, actIORF1 (SCO5087) and actVB (SCO5092), from the actinorhodin biosynthetic gene cluster in Streptomyces coelicolor A3(2). Our CRISPR-Cas9 system successfully inactivated the targeted genes. When no templates for homology-directed repair (HDR) were present, the site-specific DNA double-strand breaks (DSBs) introduced by Cas9 were repaired through the error-prone nonhomologous end joining (NHEJ) pathway, resulting in a library of deletions with variable sizes around the targeted sequence. If templates for HDR were provided at the same time, precise deletions of the targeted gene were observed with near 100% frequency. Moreover, we developed a system to efficiently and reversibly control expression of target genes, deemed CRISPRi, based on a catalytically dead variant of Cas9 (dCas9). The CRISPR-Cas9 based system described here comprises a powerful and broadly applicable set of tools to manipulate actinomycetal genomes. PMID:25806970

  18. Millisia brevis gen. nov., sp. nov., an actinomycete isolated from activated sludge foam.

    PubMed

    Soddell, Jacques A; Stainsby, Fiona M; Eales, Kathryn L; Kroppenstedt, Reiner M; Seviour, Robert J; Goodfellow, Michael

    2006-04-01

    The taxonomic position of two mycolic-acid-producing actinomycetes, isolates J81T and J82, which were recovered from activated sludge foam, was clarified. Comparative 16S rRNA gene sequence studies indicated that the organisms formed a distinct lineage within the Corynebacterineae 16S rRNA gene tree. The taxonomic integrity of this group was underpinned by a wealth of phenotypic data, notably characteristic rudimentary right-angled branching. In addition, isolate J81T contained the following: meso-diaminopimelic acid, arabinose and galactose; N-glycolated muramic acid residues; a dihydrogenated menaquinone with eight isoprene units as the predominant isoprenologue; a fatty acid profile rich in oleic and palmitoleic acids and with relatively small proportions of myristic, stearic and tuberculostearic acids; mycolic acids with 44-52 carbons; and diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannosides as major polar lipids. Strain J81T was found to have a chemotaxonomic profile that serves to distinguish it from representatives of all of the other taxa classified as belonging to the suborder Corynebacterineae. In the light of these data, it is proposed that the two isolates be classified in a novel monospecific genus. The name proposed for this taxon is Millisia brevis gen. nov., sp. nov.; strain J81T (=DSM 44463T = NRRL B-24424T) is the type strain of Millisia brevis. PMID:16585686

  19. Diversity and evolution of secondary metabolism in the marine actinomycete genus Salinispora

    PubMed Central

    Ziemert, Nadine; Lechner, Anna; Wietz, Matthias; Millán-Aguiñaga, Natalie; Chavarria, Krystle L.; Jensen, Paul Robert

    2014-01-01

    Access to genome sequence data has challenged traditional natural product discovery paradigms by revealing that the products of most bacterial biosynthetic pathways have yet to be discovered. Despite the insight afforded by this technology, little is known about the diversity and distributions of natural product biosynthetic pathways among bacteria and how they evolve to generate structural diversity. Here we analyze genome sequence data derived from 75 strains of the marine actinomycete genus Salinispora for pathways associated with polyketide and nonribosomal peptide biosynthesis, the products of which account for some of today’s most important medicines. The results reveal high levels of diversity, with a total of 124 pathways identified and 229 predicted with continued sequencing. Recent horizontal gene transfer accounts for the majority of pathways, which occur in only one or two strains. Acquired pathways are incorporated into genomic islands and are commonly exchanged within and between species. Acquisition and transfer events largely involve complete pathways, which subsequently evolve by gene gain, loss, and duplication followed by divergence. The exchange of similar pathway types at the precise chromosomal locations in different strains suggests that the mechanisms of integration include pathway-level homologous recombination. Despite extensive horizontal gene transfer there is clear evidence of species-level vertical inheritance, supporting the concept that secondary metabolites represent functional traits that help define Salinispora species. The plasticity of the Salinispora secondary metabolome provides an effective mechanism to maximize population-level secondary metabolite diversity while limiting the number of pathways maintained within any individual genome. PMID:24616526

  20. Comparative analysis of oligonucleotide primers for high-throughput screening of genes encoding adenylation domains of nonribosomal peptide synthetases in actinomycetes.

    PubMed

    Bakal, Tomas; Goo, Kian-Sim; Najmanova, Lucie; Plhackova, Kamila; Kadlcik, Stanislav; Ulanova, Dana

    2015-11-01

    In the biosynthesis of diverse natural bioactive products the adenylation domains (ADs) of nonribosomal peptide synthetases select specific precursors from the cellular pool and activate them for further incorporation into the scaffold of the final compound. Therefore, the drug discovery programs employing PCR-based screening studies of microbial collections or metagenomic libraries often use AD-coding genes as markers of relevant biosynthetic gene clusters. However, due to significant sequence diversity of ADs, the conventional approach using only one primer pair in a single screening experiment could be insufficient for maximal coverage of AD abundance. In this study, the widely used primer pair A3F/A7R was compared with the newly designed aa194F/aa413R one by 454 pyrosequencing of two sets of actinomycete strains from highly dissimilar environments: subseafloor sediments and forest soil. Individually, none of the primer pairs was able to cover the overall diversity of ADs. However, due to slightly shifted specificity of the primer pairs, the total number and diversity of identified ADs were noticeably extended when both primer pairs were used in a single assay. Additionally, the efficiency of AD detection by different primer combinations was confirmed on the model of Salinispora tropica genomic DNA of known sequence. PMID:26296377

  1. Nocardia halotolerans sp. nov., a halotolerant actinomycete isolated from saline soil.

    PubMed

    Moshtaghi Nikou, Mahdi; Ramezani, Mohaddaseh; Ali Amoozegar, Mohammad; Rasooli, Mehrnoosh; Harirchi, Sharareh; Shahzadeh Fazeli, Seyed Abolhasan; Schumann, Peter; Spröer, Cathrin; Ventosa, Antonio

    2015-09-01

    A novel halotolerant actinomycete, strain Chem15(T), was isolated from soil around Inche-Broun hypersaline wetland; its taxonomic position was determined based on a polyphasic approach. Strain Chem15(T) was strictly aerobic and tolerated NaCl up to 12.5%. The optimum temperature and pH for growth were 28-30 °C and pH 7.0-7.5, respectively. The cell wall of strain Chem15(T) contained meso-diaminopimelic acid as diamino acid and galactose, arabinose and ribose as whole-cell sugars. The major phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides. The cellular fatty acids profile consisted of C16 : 0, iso-C18 : 0, C18 : 0 10-methyl and C18 : 1ω9c, and the major respiratory quinone was MK-8(H4cycl). The G+C content of the genomic DNA was 68.0 mol%. The novel strain constituted a distinct phyletic line within the genus Nocardia, based on 16S rRNA gene sequence analysis, and was closely associated with Nocardia sungurluensis DSM 45714(T) and Nocardia alba DSM 44684(T) (98.2 and 98.1% 16S rRNA gene sequence similarity, respectively). However DNA-DNA relatedness and phenotypic data demonstrated that strain Chem15(T) was clearly different from closely related species of the genus Nocardia. It is concluded that the organism should be classified as a representative of a novel species of the genus Nocardia, for which the name Nocardia halotolerans sp. nov. is proposed. The type strain is Chem15(T) ( = IBRC-M 10490(T) = LMG 28544(T)). PMID:26297293

  2. Strain-Based Design Methodology of Large Diameter Grade X80 Linepipe

    SciTech Connect

    Lower, Mark D.

    2014-04-01

    Continuous growth in energy demand is driving oil and natural gas production to areas that are often located far from major markets where the terrain is prone to earthquakes, landslides, and other types of ground motion. Transmission pipelines that cross this type of terrain can experience large longitudinal strains and plastic circumferential elongation as the pipeline experiences alignment changes resulting from differential ground movement. Such displacements can potentially impact pipeline safety by adversely affecting structural capacity and leak tight integrity of the linepipe steel. Planning for new long-distance transmission pipelines usually involves consideration of higher strength linepipe steels because their use allows pipeline operators to reduce the overall cost of pipeline construction and increase pipeline throughput by increasing the operating pressure. The design trend for new pipelines in areas prone to ground movement has evolved over the last 10 years from a stress-based design approach to a strain-based design (SBD) approach to further realize the cost benefits from using higher strength linepipe steels. This report presents an overview of SBD for pipelines subjected to large longitudinal strain and high internal pressure with emphasis on the tensile strain capacity of high-strength microalloyed linepipe steel. The technical basis for this report involved engineering analysis and examination of the mechanical behavior of Grade X80 linepipe steel in both the longitudinal and circumferential directions. Testing was conducted to assess effects on material processing including as-rolled, expanded, and heat treatment processing intended to simulate coating application. Elastic-plastic and low-cycle fatigue analyses were also performed with varying internal pressures. Proposed SBD models discussed in this report are based on classical plasticity theory and account for material anisotropy, triaxial strain, and microstructural damage effects

  3. [Secondary Metabolites from Marine Microorganisms. I. Secondary Metabolites from Marine Actinomycetes].

    PubMed

    Orlova, T I; Bulgakova, V G; Polin, A N

    2015-01-01

    Review represents data on new active metabolites isolated from marine actinomycetes published in 2007 to 2014. Marine actinomycetes are an unlimited source of novel secondary metabolites with various biological activities. Among them there are antibiotics, anticancer compounds, inhibitors of biochemical processes. PMID:26863742

  4. Structure and Stereochemical Determination of Hypogeamicins from a Cave-Derived Actinomycete

    PubMed Central

    2015-01-01

    Culture extracts from the cave-derived actinomycete Nonomuraea specus were investigated, resulting in the discovery of a new S-bridged pyronaphthoquinone dimer and its monomeric progenitors designated hypogeamicins A–D (1–4). The structures were elucidated using NMR spectroscopy, and the relative stereochemistries of the pyrans were inferred using NOE and comparison to previously reported compounds. Absolute stereochemistry was determined using quantum chemical calculations of specific rotation and vibrational and electronic circular dichroism spectra, after an extensive conformational search and including solute–solvent polarization effects, and comparing with the corresponding experimental data for the monomeric congeners. Interestingly, the dimeric hypogeamicin A (1) was found to be cytotoxic to the colon cancer derived cell line TCT-1 at low micromolar ranges, but not bacteria, whereas the monomeric precursors possessed antibiotic activity but no significant TCT-1 cytotoxicity. PMID:25046128

  5. Multiscale strain analysis of tissue equivalents using a custom-designed biaxial testing device.

    PubMed

    Bell, B J; Nauman, E; Voytik-Harbin, S L

    2012-03-21

    Mechanical signals transferred between a cell and its extracellular matrix play an important role in regulating fundamental cell behavior. To further define the complex mechanical interactions between cells and matrix from a multiscale perspective, a biaxial testing device was designed and built. Finite element analysis was used to optimize the cruciform specimen geometry so that stresses within the central region were concentrated and homogenous while minimizing shear and grip effects. This system was used to apply an equibiaxial loading and unloading regimen to fibroblast-seeded tissue equivalents. Digital image correlation and spot tracking were used to calculate three-dimensional strains and associated strain transfer ratios at macro (construct), meso, matrix (collagen fibril), cell (mitochondria), and nuclear levels. At meso and matrix levels, strains in the 1- and 2-direction were statistically similar throughout the loading-unloading cycle. Interestingly, a significant amplification of cellular and nuclear strains was observed in the direction perpendicular to the cell axis. Findings indicate that strain transfer is dependent upon local anisotropies generated by the cell-matrix force balance. Such multiscale approaches to tissue mechanics will assist in advancement of modern biomechanical theories as well as development and optimization of preconditioning regimens for functional engineered tissue constructs. PMID:22455913

  6. Migration and strains induced by different designs of force-closed stems for THA☆

    PubMed Central

    Griza, Sandro; Gomes, Luiz Sérgio Marcelino; Cervieri, André; Strohaecker, Telmo Roberto

    2015-01-01

    Objectives Subtle differences in stem design can result in different mechanical responses of the total hip arthroplasty. Tests measuring migration of the stem relative to the femur, as well as the strains in the cement mantle and on the femur can detect different mechanical behavior between stems. Methods In this article, conical, double and triple tapered stems were implanted in composite femurs and subjected to static and cyclic loads. Stems differed mainly on taper angle, calcar radius and proximal stiffness. Stem migration and strains on the femur and in the cement mantle were achieved. Results Significant differences (p < 0.05) were noted in the permanent rotation between double and triple tapers, in the strains on the proximal medial femur between triple and both conical and double tapers, and in the strains on the lateral proximal femur between double tapers and both conical and triple tapers. Conclusion The proposed mechanical tests were able to detect significant differences in the behavior of these resembling stems. Stem proximal stiffness and the calcar radius of the stem influence its rotational stability and the strain transmission to the femur. PMID:27218081

  7. Characterization and phylogenetic analysis of novel polyene type antimicrobial metabolite producing actinomycetes from marine sediments: Bay of Bengal India

    PubMed Central

    Valan, Arasu M; Asha, KRT; Duraipandiyan, V; Ignacimuthu, S; Agastian, P

    2012-01-01

    Objective To isolate and indentify the promising antimicrobial metabolite producing Streptomyces strains from marine sediment samples from Andrapradesh coast of India. Methods Antagonistic actinomycetes were isolated by starch casein agar medium and modified nutrient agar medium with 1% glucose used as a base for primary screening. Significant antimicrobial metabolite producing strains were selected and identified by using biochemical and 16S rDNA level. Minimum inhibitory concentrations of the organic extracts were done by using broth micro dilution method. Results Among the 210 actinomycetes, 64.3% exhibited activity against Gram positive bacteria, 48.5 % showed activity towards Gram negative bacteria, 38.8% exhibited both Gram positive and negative bacteria and 80.85 % isolates revealed significant antifungal activity. However, five isolates AP-5, AP-18, AP-41 and AP-70 showed significant antimicrobial activity. The analysis of cell wall hydrolysates showed the presence of LL-diaminopimelic acid and glycine in all the isolates. Sequencing analysis indicated that the isolates shared 98.5%-99.8% sequence identity to the 16S rDNA gene sequences of the Streptomyces taxons. The antimicrobial substances were extracted using hexane and ethyl acetate from spent medium in which strains were cultivated at 30°Cfor five days. The antimicrobial activity was assessed using broth micro dilution technique. Each of the culture extracts from these five strains showed a typical polyene-like property. The lowest minimum inhibitory concentrations of ethyl acetate extracts against Escherichia coli and Curvularia lunata were 67.5 and 125.0 µg/mL, respectively. Conclusions It can be concluded that hexane and ethyl acetate soluble extracellular products of novel isolates are effective against pathogenic bacteria and fungi. PMID:23569851

  8. Design, modeling, fabrication and testing of a MEMS capacitive bending strain sensor

    NASA Astrophysics Data System (ADS)

    Aebersold, J.; Walsh, K.; Crain, M.; Voor, M.; Martin, M.; Hnat, W.; Lin, J.; Jackson, D.; Naber, J.

    2006-04-01

    Presented herein are the design, modelling, fabrication and testing of a MEMSbased capacitive bending strain sensor utilizing a comb drive. This sensor is designed to be integrated with a telemetry system that will monitor changes in bending strain to assist orthopaedic surgeons with the diagnosis of spinal fusion. ABAQUS/CAE version 6.5 finite element analysis (FEA) modelling software was used to predict sensor actuation, capacitance output and the avoidance of material failure. Highly doped boron silicon wafers with a low resistivity were fabricated into an interdigitated finger array employing deep reactive ion etching (DRIE) to create 150 µm sidewalls with 25 µm spacing between the adjacent fingers. For testing, the sensor was adhered to a steel beam, which was subjected to four-point bending. This mechanically changed the spacing between the interdigitated fingers as a function of strain. As expected, the capacitance output increased as an inverse function of the spacing between the interdigitated fingers, beginning with an initial capacitance of 7.56 pF at the unstrained state and increasing inversely to 17.04 pF at 1571 µɛ of bending strain. The FEA and analytical models were comparable with experimental data. The largest differential of 0.65 pF or 6.33% occurred at 1000 µɛ.

  9. In Vitro and In Vivo Plant Growth Promoting Activities and DNA Fingerprinting of Antagonistic Endophytic Actinomycetes Associates with Medicinal Plants

    PubMed Central

    Passari, Ajit Kumar; Mishra, Vineet Kumar; Gupta, Vijai Kumar; Yadav, Mukesh Kumar; Saikia, Ratul; Singh, Bhim Pratap

    2015-01-01

    Endophytic actinomycetes have shown unique plant growth promoting as well as antagonistic activity against fungal phytopathogens. In the present study forty-two endophytic actinomycetes recovered from medicinal plants were evaluated for their antagonistic potential and plant growth-promoting abilities. Twenty-two isolates which showed the inhibitory activity against at least one pathogen were subsequently tested for their plant-growth promoting activities and were compared genotypically using DNA based fingerprinting, including enterobacterial repetitive intergenic consensus (ERIC) and BOX repetitive elements. Genetic relatedness based on both ERIC and BOX-PCR generates specific patterns corresponding to particular genotypes. Exponentially grown antagonistic isolates were used to evaluate phosphate solubilization, siderophores, HCN, ammonia, chitinase, indole-3-acetic acid production, as well as antifungal activities. Out of 22 isolates, the amount of indole-3-acetic acid (IAA) ranging between 10–32 μg/ml was produced by 20 isolates and all isolates were positive for ammonia production ranging between 5.2 to 54 mg/ml. Among 22 isolates tested, the amount of hydroxamate-type siderophores were produced by 16 isolates ranging between 5.2 to 36.4 μg/ml, while catechols-type siderophores produced by 5 isolates ranging from 3.2 to 5.4 μg/ml. Fourteen isolates showed the solubilisation of inorganic phosphorous ranging from 3.2 to 32.6 mg/100ml. Chitinase and HCN production was shown by 19 and 15 different isolates, respectively. In addition, genes of indole acetic acid (iaaM) and chitinase (chiC) were successively amplified from 20 and 19 isolates respectively. The two potential strains Streptomyces sp. (BPSAC34) and Leifsonia xyli (BPSAC24) were tested in vivo and improved a range of growth parameters in chilli (Capsicum annuum L.) under greenhouse conditions. This study is the first published report that actinomycetes can be isolated as endophytes from within these

  10. In Vitro and In Vivo Plant Growth Promoting Activities and DNA Fingerprinting of Antagonistic Endophytic Actinomycetes Associates with Medicinal Plants.

    PubMed

    Passari, Ajit Kumar; Mishra, Vineet Kumar; Gupta, Vijai Kumar; Yadav, Mukesh Kumar; Saikia, Ratul; Singh, Bhim Pratap

    2015-01-01

    Endophytic actinomycetes have shown unique plant growth promoting as well as antagonistic activity against fungal phytopathogens. In the present study forty-two endophytic actinomycetes recovered from medicinal plants were evaluated for their antagonistic potential and plant growth-promoting abilities. Twenty-two isolates which showed the inhibitory activity against at least one pathogen were subsequently tested for their plant-growth promoting activities and were compared genotypically using DNA based fingerprinting, including enterobacterial repetitive intergenic consensus (ERIC) and BOX repetitive elements. Genetic relatedness based on both ERIC and BOX-PCR generates specific patterns corresponding to particular genotypes. Exponentially grown antagonistic isolates were used to evaluate phosphate solubilization, siderophores, HCN, ammonia, chitinase, indole-3-acetic acid production, as well as antifungal activities. Out of 22 isolates, the amount of indole-3-acetic acid (IAA) ranging between 10-32 μg/ml was produced by 20 isolates and all isolates were positive for ammonia production ranging between 5.2 to 54 mg/ml. Among 22 isolates tested, the amount of hydroxamate-type siderophores were produced by 16 isolates ranging between 5.2 to 36.4 μg/ml, while catechols-type siderophores produced by 5 isolates ranging from 3.2 to 5.4 μg/ml. Fourteen isolates showed the solubilisation of inorganic phosphorous ranging from 3.2 to 32.6 mg/100ml. Chitinase and HCN production was shown by 19 and 15 different isolates, respectively. In addition, genes of indole acetic acid (iaaM) and chitinase (chiC) were successively amplified from 20 and 19 isolates respectively. The two potential strains Streptomyces sp. (BPSAC34) and Leifsonia xyli (BPSAC24) were tested in vivo and improved a range of growth parameters in chilli (Capsicum annuum L.) under greenhouse conditions. This study is the first published report that actinomycetes can be isolated as endophytes from within these

  11. Protoplast preparation and reversion to the normal filamentous growth in antibiotic-producing uncommon actinomycetes.

    PubMed

    Marcone, Giorgia Letizia; Carrano, Lucia; Marinelli, Flavia; Beltrametti, Fabrizio

    2010-02-01

    Protoplast preparation, regeneration and fusion represent essential tools for those poorly studied biotechnologically valuable microorganisms inapplicable with the current molecular biology protocols. The protoplast production and regeneration method developed for Planobispora rosea and using the combination of hen egg-white lysozyme (HEWL) and Streptomyces globisporus mutanolysin was applied to a set of antibiotic-producing filamentous actinomycetes belonging to the Streptosporangiaceae, Micromonosporaceae and Streptomycetaceae. 10(7)-10(9) protoplasts were obtained from 100 ml of culture, after incubation times in the digestion solution ranging from a few hours to 1 or 2 days depending on the strain. The efficiency of protoplast reversion to the normal filamentous growth varied from 0.1 to nearly 50%. Analysis of cell wall peptidoglycan in three representative strains (Nonomuraea sp. ATCC 39727, Actinoplanes teichomyceticus ATCC 31121 and Streptomyces coelicolor A3(2)) has evidenced structural variations in the glycan strand and in the peptide chain, which may account for the different response to cell digestion and protoplast regeneration treatments. PMID:20057514

  12. Isolation and evaluation of proteolytic actinomycete isolates as novel inducers of pearl millet downy mildew disease protection.

    PubMed

    Jogaiah, Sudisha; Kurjogi, Mahantesh; Govind, Sharathchandra Ramasandra; Huntrike, Shekar Shetty; Basappa, Vedamurthy Ankala; Tran, Lam-Son Phan

    2016-01-01

    Native endophytic actinomycetes isolated from pearl millet roots were examined for their efficacy to protect pearl millet against downy mildew. Nineteen of 39 isolates were found to be proteolytic, of which 7 strains could directly suppress the sporangium formation of Sclerospora graminicola, the pearl millet downy mildew pathogen. Thus, mycelial suspensions containing either spores or cell-free extract of these 7 isolates were used for seed-coating and -soaking treatments to test for their induction of downy mildew resistance. Results indicated that seed-coating overall provided better protection to downy mildew than seed-soaking. In both treatments, the tested isolates demonstrated differential abilities in downy mildew disease protection, with Streptomyces griseus SJ_UOM-07-09 and Streptosporangium roseum SJ_UOM-18-09 showing the highest protection rates. Additionally, the levels of disease protection conferred by the actinomycetes were just slightly lower than that of the systemic fungicide Apron, suggesting their effectiveness. Further studies revealed that the more rapid root colonization by SJ_UOM-18-09 resulted in faster and higher induced resistance in comparison with SJ_UOM-07-09 under greenhouse conditions, indicating that SJ_UOM-18-09 was superior than SJ_UOM-07-09 in inducing resistance. Results from this study provide comprehensive information on biocontrol functions of SJ_UOM- 18-09 with great potential to control downy mildew disease in pearl millet. PMID:27499196

  13. Isolation and evaluation of proteolytic actinomycete isolates as novel inducers of pearl millet downy mildew disease protection

    PubMed Central

    Jogaiah, Sudisha; Kurjogi, Mahantesh; Govind, Sharathchandra Ramasandra; Huntrike, Shekar Shetty; Basappa, Vedamurthy Ankala; Tran, Lam-Son Phan

    2016-01-01

    Native endophytic actinomycetes isolated from pearl millet roots were examined for their efficacy to protect pearl millet against downy mildew. Nineteen of 39 isolates were found to be proteolytic, of which 7 strains could directly suppress the sporangium formation of Sclerospora graminicola, the pearl millet downy mildew pathogen. Thus, mycelial suspensions containing either spores or cell-free extract of these 7 isolates were used for seed-coating and -soaking treatments to test for their induction of downy mildew resistance. Results indicated that seed-coating overall provided better protection to downy mildew than seed-soaking. In both treatments, the tested isolates demonstrated differential abilities in downy mildew disease protection, with Streptomyces griseus SJ_UOM-07-09 and Streptosporangium roseum SJ_UOM-18-09 showing the highest protection rates. Additionally, the levels of disease protection conferred by the actinomycetes were just slightly lower than that of the systemic fungicide Apron, suggesting their effectiveness. Further studies revealed that the more rapid root colonization by SJ_UOM-18-09 resulted in faster and higher induced resistance in comparison with SJ_UOM-07-09 under greenhouse conditions, indicating that SJ_UOM-18-09 was superior than SJ_UOM-07-09 in inducing resistance. Results from this study provide comprehensive information on biocontrol functions of SJ_UOM- 18-09 with great potential to control downy mildew disease in pearl millet. PMID:27499196

  14. Simplified sensor design for temperature-strain discrimination using fiber Bragg gratings embedded in laminated composites

    NASA Astrophysics Data System (ADS)

    Rodriguez-Cobo, L.; Marques, A. T.; Lopez-Higuera, J. M.; Santos, J. L.; Frazão, O.

    2013-05-01

    Several easy-to-manufacture designs based on a pair of Fiber Bragg Gratings structure embedded in Carbon Fiber Reinforced Plastic (CFRP) have been explored. These smart composites can be used for strain and temperature discrimination. A Finite Elements Analysis and Matlab software were used to study the mechanical responses and its optical behaviors. The results exhibited different sensitivity and using a matrix method it is possible to compensate the thermal drift in a real application keeping a simple manufacture process.

  15. Actinopolyspora saharensis sp. nov., a novel halophilic actinomycete isolated from a Saharan soil of Algeria.

    PubMed

    Meklat, Atika; Bouras, Noureddine; Zitouni, Abdelghani; Mathieu, Florence; Lebrihi, Ahmed; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter; Sabaou, Nasserdine

    2013-04-01

    A novel halophilic actinomycete, strain H32(T), was isolated from a Saharan soil sample collected in El-Oued province, south Algeria. The isolate was characterized by means of polyphasic taxonomy. Optimal growth was determined to occur at 28-32 °C, pH 6.0-7.0 and in the presence of 15-25 % (w/v) NaCl. The strain was observed to produce abundant aerial mycelium, which formed long chains of rod-shaped spores at maturity, and fragmented substrate mycelium. The cell wall was determined to contain meso-diaminopimelic acid and the characteristic whole-cell sugars were arabinose and galactose. The predominant menaquinones were found to be MK-10(H4) and MK-9(H4). The predominant cellular fatty acids were determined to be anteiso C17:0, iso-C15:0 and iso-C16:0. The diagnostic phospholipid detected was phosphatidylcholine. Phylogenetic analyses based on the 16S rRNA gene sequence showed that this strain formed a distinct phyletic line within the radiation of the genus Actinopolyspora. The 16S rRNA gene sequence similarity indicated that strain H32(T) was most closely related to 'Actinopolyspora algeriensis' DSM 45476(T) (98.8 %) and Actinopolyspora halophila DSM 43834(T) (98.5 %). Furthermore, the result of DNA-DNA hybridization between strain H32(T) and the type strains 'A. algeriensis' DSM 45476(T), A. halophila DSM 43834(T) and Actinopolyspora mortivallis DSM 44261(T) demonstrated that this isolate represents a different genomic species in the genus Actinopolyspora. Moreover, the physiological and biochemical data allowed the differentiation of strain H32(T) from its closest phylogenetic neighbours. Therefore, it is proposed that strain H32(T) represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora saharensis sp. nov. is proposed. The type strain is H32(T) (=DSM 45459(T)=CCUG 62966(T)). PMID:23196893

  16. Discovery of phosphonic acid natural products by mining the genomes of 10,000 actinomycetes.

    PubMed

    Ju, Kou-San; Gao, Jiangtao; Doroghazi, James R; Wang, Kwo-Kwang A; Thibodeaux, Christopher J; Li, Steven; Metzger, Emily; Fudala, John; Su, Joleen; Zhang, Jun Kai; Lee, Jaeheon; Cioni, Joel P; Evans, Bradley S; Hirota, Ryuichi; Labeda, David P; van der Donk, Wilfred A; Metcalf, William W

    2015-09-29

    Although natural products have been a particularly rich source of human medicines, activity-based screening results in a very high rate of rediscovery of known molecules. Based on the large number of natural product biosynthetic genes in microbial genomes, many have proposed "genome mining" as an alternative approach for discovery efforts; however, this idea has yet to be performed experimentally on a large scale. Here, we demonstrate the feasibility of large-scale, high-throughput genome mining by screening a collection of over 10,000 actinomycetes for the genetic potential to make phosphonic acids, a class of natural products with diverse and useful bioactivities. Genome sequencing identified a diverse collection of phosphonate biosynthetic gene clusters within 278 strains. These clusters were classified into 64 distinct groups, of which 55 are likely to direct the synthesis of unknown compounds. Characterization of strains within five of these groups resulted in the discovery of a new archetypical pathway for phosphonate biosynthesis, the first (to our knowledge) dedicated pathway for H-phosphinates, and 11 previously undescribed phosphonic acid natural products. Among these compounds are argolaphos, a broad-spectrum antibacterial phosphonopeptide composed of aminomethylphosphonate in peptide linkage to a rare amino acid N(5)-hydroxyarginine; valinophos, an N-acetyl l-Val ester of 2,3-dihydroxypropylphosphonate; and phosphonocystoximate, an unusual thiohydroximate-containing molecule representing a new chemotype of sulfur-containing phosphonate natural products. Analysis of the genome sequences from the remaining strains suggests that the majority of the phosphonate biosynthetic repertoire of Actinobacteria has been captured at the gene level. This dereplicated strain collection now provides a reservoir of numerous, as yet undiscovered, phosphonate natural products. PMID:26324907

  17. Discovery of phosphonic acid natural products by mining the genomes of 10,000 actinomycetes

    PubMed Central

    Ju, Kou-San; Gao, Jiangtao; Doroghazi, James R.; Wang, Kwo-Kwang A.; Thibodeaux, Christopher J.; Li, Steven; Metzger, Emily; Fudala, John; Su, Joleen; Zhang, Jun Kai; Lee, Jaeheon; Cioni, Joel P.; Evans, Bradley S.; Hirota, Ryuichi; Labeda, David P.; van der Donk, Wilfred A.; Metcalf, William W.

    2015-01-01

    Although natural products have been a particularly rich source of human medicines, activity-based screening results in a very high rate of rediscovery of known molecules. Based on the large number of natural product biosynthetic genes in microbial genomes, many have proposed “genome mining” as an alternative approach for discovery efforts; however, this idea has yet to be performed experimentally on a large scale. Here, we demonstrate the feasibility of large-scale, high-throughput genome mining by screening a collection of over 10,000 actinomycetes for the genetic potential to make phosphonic acids, a class of natural products with diverse and useful bioactivities. Genome sequencing identified a diverse collection of phosphonate biosynthetic gene clusters within 278 strains. These clusters were classified into 64 distinct groups, of which 55 are likely to direct the synthesis of unknown compounds. Characterization of strains within five of these groups resulted in the discovery of a new archetypical pathway for phosphonate biosynthesis, the first (to our knowledge) dedicated pathway for H-phosphinates, and 11 previously undescribed phosphonic acid natural products. Among these compounds are argolaphos, a broad-spectrum antibacterial phosphonopeptide composed of aminomethylphosphonate in peptide linkage to a rare amino acid N5-hydroxyarginine; valinophos, an N-acetyl l-Val ester of 2,3-dihydroxypropylphosphonate; and phosphonocystoximate, an unusual thiohydroximate-containing molecule representing a new chemotype of sulfur-containing phosphonate natural products. Analysis of the genome sequences from the remaining strains suggests that the majority of the phosphonate biosynthetic repertoire of Actinobacteria has been captured at the gene level. This dereplicated strain collection now provides a reservoir of numerous, as yet undiscovered, phosphonate natural products. PMID:26324907

  18. Studies on carboxymethyl cellulase produced by an alkalothermophilic actinomycete.

    PubMed

    George, S P; Ahmad, A; Rao, M B

    2001-04-01

    A novel alkalothermophilic actinomycete having optimum growth at pH 9 and 50 degrees C was isolated from self-heating compost from the Barabanki district of Uttar Pradesh, India. Based on its morphology, susceptibility of spores to heat and novobiocin, guaninecytosine content of chromosomal DNA and cell wall composition, the organism was classified under Thermomonospora. The alkalothermophilic actinomycete produced 23 IU/ml carboxymethyl cellulase (CMCase). The CMCase was purified by fractional ammonium sulphate precipitation followed by cellulose affinity chromatography and Sephacryl S-200 gel filtration. The CMCase had a molecular weight of 38 KD and pI of 4.1. The enzyme exhibited optimum activity at pH 5 and temperature 50 degrees C. The CMCase showed pH stability in the range 7-10. The enzyme retained 100% activity at 50 degrees C for 72 h and had half-lives of 7 and 3 h at 60 degrees C and 70 degrees C, respectively. The CMCase was stable in the presence of commercial detergents such as Ariel, Henko and Surf Excel, indicating its potential as an additive to laundry detergents. PMID:11272024

  19. Molecular insights on the biosynthesis of antitumour compounds by actinomycetes

    PubMed Central

    Olano, Carlos; Méndez, Carmen; Salas, José A.

    2011-01-01

    Summary Natural products are traditionally the main source of drug leads. In particular, many antitumour compounds are either natural products or derived from them. However, the search for novel antitumour drugs active against untreatable tumours, with fewer side‐effects or with enhanced therapeutic efficiency, is a priority goal in cancer chemotherapy. Microorganisms, particularly actinomycetes, are prolific producers of bioactive compounds, including antitumour drugs, produced as secondary metabolites. Structural genes involved in the biosynthesis of such compounds are normally clustered together with resistance and regulatory genes, which facilitates the isolation of the gene cluster. The characterization of these clusters has represented, during the last 25 years, a great source of genes for the generation of novel derivatives by using combinatorial biosynthesis approaches: gene inactivation, gene expression, heterologous expression of the clusters or mutasynthesis. In addition, these techniques have been also applied to improve the production yields of natural and novel antitumour compounds. In this review we focus on some representative antitumour compounds produced by actinomycetes covering the genetic approaches used to isolate and validate their biosynthesis gene clusters, which finally led to generating novel derivatives and to improving the production yields. PMID:21342461

  20. Genomic Libraries and a Host Strain Designed for Highly Efficient Two-Hybrid Selection in Yeast

    PubMed Central

    James, P.; Halladay, J.; Craig, E. A.

    1996-01-01

    The two-hybrid system is a powerful technique for detecting protein-protein interactions that utilizes the well-developed molecular genetics of the yeast Saccharomyces cerevisiae. However, the full potential of this technique has not been realized due to limitations imposed by the components available for use in the system. These limitations include unwieldy plasmid vectors, incomplete or poorly designed two-hybrid libraries, and host strains that result in the selection of large numbers of false positives. We have used a novel multienzyme approach to generate a set of highly representative genomic libraries from S. cerevisiae. In addition, a unique host strain was created that contains three easily assayed reporter genes, each under the control of a different inducible promoter. This host strain is extremely sensitive to weak interactions and eliminates nearly all false positives using simple plate assays. Improved vectors were also constructed that simplify the construction of the gene fusions necessary for the two-hybrid system. Our analysis indicates that the libraries and host strain provide significant improvements in both the number of interacting clones identified and the efficiency of two-hybrid selections. PMID:8978031

  1. New Dimensions of Research on Actinomycetes: Quest for Next Generation Antibiotics.

    PubMed

    Jose, Polpass Arul; Jha, Bhavanath

    2016-01-01

    Starting with the discovery of streptomycin, the promise of natural products research on actinomycetes has been captivating researchers and offered an array of life-saving antibiotics. However, most of the actinomycetes have received a little attention of researchers beyond isolation and activity screening. Noticeable gaps in genomic information and associated biosynthetic potential of actinomycetes are mainly the reasons for this situation, which has led to a decline in the discovery rate of novel antibiotics. Recent insights gained from genome mining have revealed a massive existence of previously unrecognized biosynthetic potential in actinomycetes. Successive developments in next-generation sequencing, genome editing, analytical separation and high-resolution spectroscopic methods have reinvigorated interest on such actinomycetes and opened new avenues for the discovery of natural and natural-inspired antibiotics. This article describes the new dimensions that have driven the ongoing resurgence of research on actinomycetes with historical background since the commencement in 1940, for the attention of worldwide researchers. Coupled with increasing advancement in molecular and analytical tools and techniques, the discovery of next-generation antibiotics could be possible by revisiting the untapped potential of actinomycetes from different natural sources. PMID:27594853

  2. New Dimensions of Research on Actinomycetes: Quest for Next Generation Antibiotics

    PubMed Central

    Jose, Polpass Arul; Jha, Bhavanath

    2016-01-01

    Starting with the discovery of streptomycin, the promise of natural products research on actinomycetes has been captivating researchers and offered an array of life-saving antibiotics. However, most of the actinomycetes have received a little attention of researchers beyond isolation and activity screening. Noticeable gaps in genomic information and associated biosynthetic potential of actinomycetes are mainly the reasons for this situation, which has led to a decline in the discovery rate of novel antibiotics. Recent insights gained from genome mining have revealed a massive existence of previously unrecognized biosynthetic potential in actinomycetes. Successive developments in next-generation sequencing, genome editing, analytical separation and high-resolution spectroscopic methods have reinvigorated interest on such actinomycetes and opened new avenues for the discovery of natural and natural-inspired antibiotics. This article describes the new dimensions that have driven the ongoing resurgence of research on actinomycetes with historical background since the commencement in 1940, for the attention of worldwide researchers. Coupled with increasing advancement in molecular and analytical tools and techniques, the discovery of next-generation antibiotics could be possible by revisiting the untapped potential of actinomycetes from different natural sources. PMID:27594853

  3. Metabolic design of a platform Escherichia coli strain producing various chorismate derivatives.

    PubMed

    Noda, Shuhei; Shirai, Tomokazu; Oyama, Sachiko; Kondo, Akihiko

    2016-01-01

    A synthetic metabolic pathway suitable for the production of chorismate derivatives was designed in Escherichia coli. An L-phenylalanine-overproducing E. coli strain was engineered to enhance the availability of phosphoenolpyruvate (PEP), which is a key precursor in the biosynthesis of aromatic compounds in microbes. Two major reactions converting PEP to pyruvate were inactivated. Using this modified E.coli as a base strain, we tested our system by carrying out the production of salicylate, a high-demand aromatic chemical. The titer of salicylate reached 11.5 g/L in batch culture after 48 h cultivation in a 2-liter jar fermentor, and the yield from glucose as the sole carbon source exceeded 40% (mol/mol). In this test case, we found that pyruvate was synthesized primarily via salicylate formation and the reaction converting oxaloacetate to pyruvate. In order to demonstrate the generality of our designed strain, we employed this platform for the production of each of 7 different chorismate derivatives. Each of these industrially important chemicals was successfully produced to levels of 1-3g/L in test tube-scale culture. PMID:26654797

  4. Studies on Actinomycetal Resources under Extreme Environments in the West of China

    NASA Astrophysics Data System (ADS)

    Li, W.

    2005-12-01

    s: Actinomycetes play a quite important role in natural ecological system and they are also profile producers of antibiotics, antitumor agents, enzymes, enzyme inhibitors and immunomodifiers. which have been widely applied in industry, agriculture, forestry and pharmaceutical industry. In the past, the research work on actinomycetes was mainly concentrated on that of common habitats. Actinomycetes resources under extreme environments (including extreme high and low temperature, extreme high or low pH, high salt concentration etc.) have received comparatively little attention from microbiologists. Actinomycetes are regarded as one kind of sideline microorganisms and those under extreme environments are better materials for biological evolution and phylogenetic development in research. There are much more unknown species and much more worth researching for actinomycetes under extreme environments. There are many extreme environmental resources in the west of China. For example, wide range snow-mountains, basified soil and lakes, widely distributed acid and alkaline hot-springs in Yunnan provinces; more than 73.3 million hektares basified soil and salt lakes in Xinjiang Province and many unusual environments in Qinghai Province and other western Provinces. They were mostly precious natural resources and were destroyed, relatively fewer can provided us with unique conditions for study on actinomycetal resources under extreme environments. In recent years, our main work was focusing on study of extremophilic actinomycetal resources in the west of China by using conventional cultivation-methods and culture-independent methods (PCR-clone and DGGE/TGGE, etc), Results showed that large amount of unknown microbial resources (including actinomycetal resources) existed in natural extreme environments. Additionally, lots of new taxa were isolated and characterized using a polyphasic approach. Further, we got some new compounds with different bioactivities from these

  5. Optimized design and simulation of high temperature pressure pipeline strain monitoring with optical fiber sensing technology

    NASA Astrophysics Data System (ADS)

    Zhang, Feng; Liu, Yueming; Lou, Jun

    2011-08-01

    methods mentioned above cannot satisfy the strain change monitoring of high temperature pressure piping. In this paper a novel method is presented using optical Fiber Bragg Grating sensor to carry on the real-time monitoring of the high temperature pressure piping surface strain change. firstly the stress and strain analysis of the high temperature pressure piping surface is given based on the established theoretical model, then optimized design and simulation is accomplished with computer ANSYS software. In the end a optimized set-up is put forward and discussed.

  6. Improved Kolsky-bar design for mechanical characterization of materials at high strain rates

    NASA Astrophysics Data System (ADS)

    Song, Bo; Connelly, Kevin; Korellis, John; Lu, Wei-Yang; Antoun, Bonnie R.

    2009-11-01

    A Kolsky apparatus with numerous modifications has been designed for mechanical characterization of materials at high strain rates. These modifications include employing a highly precise optical table, pillow blocks with Frelon®-coated linear bearings as bar supports and a laser system for better precision bar alignment, etc. In addition, the striker bars were coated with Teflon® to minimize the friction with the gun barrel after removal of the conventional plastic sabots. This new design significantly simplifies the alignment process, improving the final alignment and calibration in the bar system; both are critical for validity and accuracy of the resulting data. An example of a dynamic experiment on a 6061 aluminum specimen by using this newly designed Kolsky bar is also presented.

  7. Description of Kibdelosporangium banguiense sp. nov., a novel actinomycete isolated from soil of the forest of Pama, on the plateau of Bangui, Central African Republic.

    PubMed

    Pascual, Javier; González, Ignacio; Estévez, Mar; Benito, Patricia; Trujillo, Martha E; Genilloud, Olga

    2016-05-01

    A novel actinomycete strain F-240,109(T) from the MEDINA collection was isolated from a soil sample collected in the forest of Pama, on the plateau of Bangui, Central African Republic. The strain was identified according to its 16S rRNA gene sequence as a new member of the genus Kibdelosporangium, being closely related to Kibdelosporangium aridum subsp. aridum (98.6 % sequence similarity), Kibledosporangium phytohabitans (98.3 %), Kibdelosporangium aridum subsp. largum (97.7 %), Kibdelosporangium philippinense (97.6 %) and Kibledosporangium lantanae (96.9 %). In order to resolve its precise taxonomic status, the strain was characterised through a polyphasic approach. The strain is a Gram-stain positive, aerobic, non-motile and catalase-positive actinomycete characterised by formation of extensively branched substrate mycelia and sparse brownish grey aerial mycelia with sporangium-like globular structures. The chemotaxonomic characterisation of strain F-240,109(T) corroborated its affiliation into the genus Kibdelosporangium. The peptidoglycan contains meso-diaminopimelic acid; the major menaquinone is MK-9(H4); the phospholipid profile contains high amounts of phosphatidylethanolamine, hydroxyphosphatidylethanolamine, diphosphatidylglycerol and an unidentified phospholipid; and the predominant cellular fatty acid methyl esters are iso-C16:0, iso-C14:0, iso-C15:0 and 2OH iso-C16:0. However, some key phenotypic differences regarding to its close relatives and DNA-DNA hybridization values indicate that strain F-240,109(T) represents a novel Kibdelosporangium species, for which the name Kibdelosporangium banguiense sp. nov. is proposed. The type strain is strain F-240,109(T) (=DSM 46670(T), =LMG 28181(T)). PMID:26936255

  8. Conceptual Design of a Wireless Strain Monitoring System for Space Applications

    NASA Astrophysics Data System (ADS)

    Broutas, Panagiotis; Bitzaros, Stathis Kyriakis; Goustouridis, Dimitrios; Katsafouros, Stavros; Tsoukalas, Dimitrios; Chatzandroulis, Stavros

    The conceptual design of the architecture of a wireless strain monitoring network suitable for space applications is presented. The system is a heterogeneous wireless network that consists of battery powered nodes and batteryless nodes that are able to harvest energy from an incident RF field. Battery powered nodes are based on the Zigbee standard. Both battery and batteryless nodes are envisioned to include sensors but some battery powered nodes could simply serve as relaying points to transfer data to the central computer. The structure of the batteryless nodes as well as remote powering and data transmission are analyzed.

  9. Specificity of actinomycetal complexes in urbanozems of the city of Kirov

    NASA Astrophysics Data System (ADS)

    Shirokikh, I. G.; Ashikhmina, T. Ya.; Shirokikh, A. A.

    2011-02-01

    The number and composition of the actinomycetal population was studied in urbanozems in the city of Kirov. It was shown that the total population of actinomycetes was an order of magnitude lower than that in the background territories, and the generic structure of the actinomycetal complex and the species composition of the streptomycetes were transformed under the influence of the urbanization factors. The obtained data were compared with the concentrations of the mobile forms of Pb, Zn, Cu, Fe, and Mn in different ecotopes (industrial, traffic, and recreation zones). The increase of the relative portion of micromonosporic actinomycetes in comparison with the background (reference) soils was observed in the complexes of the industrial and transport ecotopes mostly contaminated with heavy metals. It was found that the antibiotic potential of the streptomycetes in the contaminated soils was lower than in the soils of the background territories.

  10. Marine actinomycetes as an emerging resource for the drug development pipelines.

    PubMed

    Zotchev, Sergey B

    2012-04-30

    Many representatives of the order Actinomycetales are prolific producers of thousands of biologically active secondary metabolites. Actinomycetes from terrestrial sources have been studied and screened since the 1950s, yielding many important anti-infective and anti-cancer drugs. However, frequent re-discovery of the same compounds in terrestrial actinomycetes have made them less attractive for screening programs in the recent years. At the same time, actinomycetes isolated from the marine environment currently receive considerable attention due to the structural diversity and unique biological activities of their secondary metabolites. This review highlights achievements and challenges in the isolation of marine actinomycetes, some examples of bioactive metabolites identified by conventional screening, and presents new developments in the field of genome mining and heterologous expression of biosynthetic gene clusters leading to the discovery of novel compounds. PMID:21683100

  11. Diversity of actinomycetes isolated from subseafloor sediments after prolonged low-temperature storage.

    PubMed

    Ulanova, Dana; Goo, Kian-Sim

    2015-05-01

    Subseafloor sediments present an untapped source of novel bacterial species with industrially important bioactivities. Subseafloor core samples collected during the Integrated Ocean Drilling Program Expeditions 315, 316, and 331 and stored in Kochi Core Center at -80 °C for 1 to 4 years were used for cultivation-based study of viable actinomycetes. In total, more than 100 actinomycete-like colonies were isolated from two deep-frozen subseafloor sediment samples. Isolated actinomycetes showed close similarity to known Actinotalea, Dietzia, Gordonia, Isoptericola, Microbacterium, Nocardia, Rhodococcus, Pseudonocardia, Streptomyces, and Tsukamurella species and were halotolerant. Bioactivity assays revealed that two of the isolates were producing potent antibacterial compound(s) and one isolate was having antifungal activity. Our study demonstrated that deep-frozen subseafloor core samples could be a potential source of viable actinomycetes, which may be used in drug discovery. PMID:25381631

  12. Psychrotolerant actinomycetes of plants and organic horizons in tundra and taiga soils

    NASA Astrophysics Data System (ADS)

    Dubrova, M. S.; Zenova, G. M.; Yakushev, A. V.; Manucharova, N. A.; Makarova, E. P.; Zvyagintsev, D. G.; Chernov, I. Yu.

    2013-08-01

    It has been revealed that in organic horizons and plants of the tundra and taiga ecosystems under low temperatures, actinomycetal complexes form. The population density of psychrotolerant actinomycetes in organic horizons and plants reaches tens and hundreds of thousands CFU/g of substrate or soil, and decreases in the sequence litters > plants > soils > undecomposed plant remains > moss growths. The mycelium length of psychrotolerant actinomycetes reaches 220 m/g of substrate. Application of the FISH method has demonstrated that metabolically active psychrotolerant bacteria of the phylum Actinobacteria constitute 30% of all metabolically active psychrotolerant representatives of the Bacterià domain of the prokaryotic microbial community of soils and plants. Psychrotolerant actinomycetes in tundra and taiga ecosystems possess antimicrobial properties.

  13. Stimulation of 2-methylisoborneol (MIB) production by actinomycetes after cyclic chlorination in drinking water distribution systems.

    PubMed

    Abbaszadegan, Morteza; Yi, Min; Alum, Absar

    2015-01-01

    The impact of fluctuation in chlorine residual on actinomycetes and the production of 2-methylisoborneol (MIB) were studied in cast-iron and PVC model distribution systems. Actinomycetes were spiked in each system and continued operation for a 12-day non-chlorine experiment, resulting in no changes in actinomycetes and MIB concentrations. Three cyclic chlorination events were performed and chlorine residuals were maintained as follows: 1.0 mg L(-1) for 24 h, 0 mg L(-1) for 48 h, 0.5 mg L(-1) for 48 h, 0 mg L(-1) for 48 h and 2 mg L(-1) for 24 h. After each chlorination event, 2 -3 log decrease in actinomycetes was noted in both systems. However, within 48 h at 0 mg L(-1) chlorine, the actinomycetes recovered to the pre-chlorination levels. On the contrary, MIB concentration in both systems remained un-impacted after the first cycle and increased by fourfold (< 5 to > 20 mg L(-1)) after the second cycle, which lasted through the third cycle despite the fact that actinomycetes numbers fluctuated 2-3 logs during this time period. For obtaining biofilm samples from field, water meters were collected from municipality drinking water distribution systems located in central Arizona. The actinomycetes concentration in asbestos cement pipe and cast iron pipe averaged 3.1 × 10(3) and 1.9 × 10(4) CFU cm(-2), respectively. The study shows that production of MIB is associated with changes in chlorine residual in the systems. This is the first report of cyclic chlorine shock as a stimulus for MIB production by actinomycetes in drinking water distribution system's ecology. PMID:25723062

  14. Exploring plant growth-promotion actinomycetes from vermicompost and rhizosphere soil for yield enhancement in chickpea.

    PubMed

    Sreevidya, M; Gopalakrishnan, S; Kudapa, H; Varshney, R K

    2016-01-01

    The main objective of the present study was to isolate and characterize actinomycetes for their plant growth-promotion in chickpea. A total of 89 actinomycetes were screened for their antagonism against fungal pathogens of chickpea by dual culture and metabolite production assays. Four most promising actinomycetes were evaluated for their physiological and plant growth-promotion properties under in vitro and in vivo conditions. All the isolates exhibited good growth at temperatures from 20°C to 40°C, pH range of 7-11 and NaCl concentrations up to 8%. These were also found highly tolerant to Bavistin, slightly tolerant to Thiram and Captan (except VAI-7 and VAI-40) but susceptible to Benlate and Ridomil at field application levels and were found to produce siderophore, cellulase, lipase, protease, chitinase (except VAI-40), hydrocyanic acid (except VAI-7 and VAI-40), indole acetic acid and β-1,3-glucanase. When the four actinomycetes were evaluated for their plant growth-promotion properties under field conditions on chickpea, all exhibited increase in nodule number, shoot weight and yield. The actinomycetes treated plots enhanced total N, available P and organic C over the un-inoculated control. The scanning electron microscope studies exhibited extensive colonization by actinomycetes on the root surface of chickpea. The expression profiles for indole acetic acid, siderophore and β-1,3-glucanase genes exhibited up-regulation for all three traits and in all four isolates. The actinomycetes were identified as Streptomyces but different species in the 16S rDNA analysis. It was concluded that the selected actinomycetes have good plant growth-promotion and biocontrol potentials on chickpea. PMID:26887230

  15. Exploring plant growth-promotion actinomycetes from vermicompost and rhizosphere soil for yield enhancement in chickpea

    PubMed Central

    Sreevidya, M.; Gopalakrishnan, S.; Kudapa, H.; Varshney, R.K.

    2016-01-01

    The main objective of the present study was to isolate and characterize actinomycetes for their plant growth-promotion in chickpea. A total of 89 actinomycetes were screened for their antagonism against fungal pathogens of chickpea by dual culture and metabolite production assays. Four most promising actinomycetes were evaluated for their physiological and plant growth-promotion properties under in vitro and in vivo conditions. All the isolates exhibited good growth at temperatures from 20 °C to 40 °C, pH range of 7–11 and NaCl concentrations up to 8%. These were also found highly tolerant to Bavistin, slightly tolerant to Thiram and Captan (except VAI-7 and VAI-40) but susceptible to Benlate and Ridomil at field application levels and were found to produce siderophore, cellulase, lipase, protease, chitinase (except VAI-40), hydrocyanic acid (except VAI-7 and VAI-40), indole acetic acid and β-1,3-glucanase. When the four actinomycetes were evaluated for their plant growth-promotion properties under field conditions on chickpea, all exhibited increase in nodule number, shoot weight and yield. The actinomycetes treated plots enhanced total N, available P and organic C over the un-inoculated control. The scanning electron microscope studies exhibited extensive colonization by actinomycetes on the root surface of chickpea. The expression profiles for indole acetic acid, siderophore and β-1,3-glucanase genes exhibited up-regulation for all three traits and in all four isolates. The actinomycetes were identified as Streptomyces but different species in the 16S rDNA analysis. It was concluded that the selected actinomycetes have good plant growth-promotion and biocontrol potentials on chickpea. PMID:26887230

  16. Psoas abscess caused by actinomycete together with Escherichia coli infection: a case report and literature review

    PubMed Central

    Chen, Qian; Ding, Wenyuan; Yang, Dalong

    2014-01-01

    Psoas abscesses are classified into primary or secondary according to infectious etiology. However, the psoas abscess caused by actinomycete together with Escherichia coli infection is very rare. Here we report a case of psoas abscess caused by actinomycete together with Escherichia coli infection in a young woman. The disease was treated successfully. A literature review of psoas abscess in relation to its etiology, identification, and difficulties in the treatment is also presented. PMID:25356161

  17. A strain-absorbing design for tissue-machine interfaces using a tunable adhesive gel.

    PubMed

    Lee, Sungwon; Inoue, Yusuke; Kim, Dongmin; Reuveny, Amir; Kuribara, Kazunori; Yokota, Tomoyuki; Reeder, Jonathan; Sekino, Masaki; Sekitani, Tsuyoshi; Abe, Yusuke; Someya, Takao

    2014-01-01

    To measure electrophysiological signals from the human body, it is essential to establish stable, gentle and nonallergic contacts between the targeted biological tissue and the electrical probes. However, it is difficult to form a stable interface between the two for long periods, especially when the surface of the biological tissue is wet and/or the tissue exhibits motion. Here we resolve this difficulty by designing and fabricating smart, stress-absorbing electronic devices that can adhere to wet and complex tissue surfaces and allow for reliable, long-term measurements of vital signals. We demonstrate a multielectrode array, which can be attached to the surface of a rat heart, resulting in good conformal contact for more than 3 h. Furthermore, we demonstrate arrays of highly sensitive, stretchable strain sensors using a similar design. Ultra-flexible electronics with enhanced adhesion to tissue could enable future applications in chronic in vivo monitoring of biological signals. PMID:25523614

  18. Design of Stress-Strain Measuring System for Bulldozing Plate Based on Virtual Instrument Technology

    NASA Astrophysics Data System (ADS)

    Xu, S. C.; Li, J. Q.; Zhang, R.

    2006-10-01

    Soil is a kind of discrete, multiphase compound that is composed of soil particles, liquid and air. When soil is disturbed by bulldozing plate, the mechanical behavior of the soil will become very complex. Based on the law of action and reaction, the dynamic mechanical behavior of disturbed soil was indirectly analyzed by measuring and studying the forces on the bulldozing plate by soil currently, so a stress-strain virtual measuring system for bulldozing plate, which was designed by the graphical programming language DASYLab, was used to measure the horizontal force Fz acting on the bulldozing plate. In addition, during the course of design, the experimental complexities and the interferential factors influencing on signal logging were analyzed when bulldozing plate worked, so the anti-jamming methods of hardware and software technology were adopted correlatively. In the end, the horizontal force Fz was analyzed with Error Theory, the result shown that the quantificational analysis of Fz were identical to the qualitative results of soil well, and the error of the whole test system is under 5 percent, so the tress-strain virtual measuring system was stable and credible.

  19. Biodegradation of cis-1,4-Polyisoprene Rubbers by Distinct Actinomycetes: Microbial Strategies and Detailed Surface Analysis

    PubMed Central

    Linos, Alexandros; Berekaa, Mahmoud M.; Reichelt, Rudolf; Keller, Ulrike; Schmitt, Jürgen; Flemming, Hans-Curt; Kroppenstedt, Reiner M.; Steinbüchel, Alexander

    2000-01-01

    Several actinomycetes isolated from nature were able to use both natural rubber (NR) and synthetic cis-1,4-polyisoprene rubber (IR) as a sole source of carbon. According to their degradation behavior, they were divided into two groups. Representatives of the first group grew only in direct contact to the rubber substrate and led to considerable disintegration of the material during cultivation. The second group consisted of weaker rubber decomposers that did not grow adhesively, as indicated by the formation of clear zones (translucent halos) around bacterial colonies after cultivation on NR dispersed in mineral agar. Taxonomic analysis of four selected strains based on 16S rRNA similarity examinations revealed two Gordonia sp. strains, VH2 and Kb2, and one Mycobacterium fortuitum strain, NF4, belonging to the first group as well as one Micromonospora aurantiaca strain, W2b, belonging to the second group. Schiff's reagent staining tests performed for each of the strains indicated colonization of the rubber surface, formation of a bacterial biofilm, and occurrence of compounds containing aldehyde groups during cultivation with NR latex gloves. Detailed analysis by means of scanning electron microscopy yielded further evidence for the two different microbial strategies and clarified the colonization efficiency. Thereby, strains VH2, Kb2, and NF4 directly adhered to and merged into the rubber material, while strain W2b produced mycelial corridors, especially on the surface of IR. Fourier transform infrared spectroscopy comprising the attenuated total reflectance technique was applied on NR latex gloves overgrown by cells of the Gordonia strains, which were the strongest rubber decomposers. Spectra demonstrated the decrease in number of cis-1,4 double bonds, the formation of carbonyl groups, and the change of the overall chemical environment, indicating that an oxidative attack at the double bond is the first metabolic step of the biodegradation process. PMID:10742254

  20. Continuing hunt for endophytic actinomycetes as a source of novel biologically active metabolites.

    PubMed

    Masand, Meeta; Jose, Polpass Arul; Menghani, Ekta; Jebakumar, Solomon Robinson David

    2015-12-01

    Drug-resistant pathogens and persistent agrochemicals mount the detrimental threats against human health and welfare. Exploitation of beneficial microorganisms and their metabolic inventions is most promising way to tackle these two problems. Since the successive discoveries of penicillin and streptomycin in 1940s, numerous biologically active metabolites have been discovered from different microorganisms, especially actinomycetes. In recent years, actinomycetes that inhabit unexplored environments have received significant attention due to their broad diversity and distinctive metabolic potential with medical, agricultural and industrial importance. In this scenario, endophytic actinomycetes that inhabit living tissues of plants are emerging as a potential source of novel bioactive compounds for the discovery of drug leads. Also, endophytic actinomycetes are considered as bio-inoculants to improve crop performance through organic farming practices. Further efforts on exploring the endophytic actinomycetes associated with the plants warrant the likelihood of discovering new taxa and their metabolites with novel chemical structures and biotechnological importance. This mini-review highlights the recent achievements in isolation of endophytic actinomycetes and an assortment of bioactive compounds. PMID:26410426

  1. Bioactive Potential of Actinomycetes from Less Explored Ecosystems against Mycobacterium tuberculosis and Other Nonmycobacterial Pathogens.

    PubMed

    Manikkam, Radhakrishnan; Venugopal, Gopikrishnan; Subramaniam, Balaji; Ramasamy, Balagurunathan; Kumar, Vanaja

    2014-01-01

    Bioactive potential of actinomycetes isolated from certain less explored Indian ecosystems against Mycobacterium tuberculosis and other nonmycobacterial pathogens was investigated. Actinomycetes were isolated from the soil samples collected from desert, coffee plantation, rubber forest, and hill area and their cultural and micromorphological characteristics were studied. Crude extracts were prepared by agar surface fermentation and tested against M. tuberculosis isolates by luciferase reporter phage (LRP) assay at 100 µg/mL. Activity against nonmycobacterial pathogens was studied by agar plug method. Totally 54 purified cultures of actinomycetes including 43 Streptomyces and 11 non-Streptomyces were isolated. While screening for antitubercular activity, extracts of 39 actinomycetes showed activity against one or more M. tuberculosis isolates whereas 27 isolates exhibited antagonistic activity against nonmycobacterial pathogens. In particular crude extracts from sixteen actinomycete isolates inhibited all the three M. tuberculosis isolates tested. Findings of the present study concluded that less explored ecosystems investigated in this study are the potential resource for bioactive actinomycetes. Further purification and characterization of active molecule from the potential extracts will pave the way for determination of MIC, toxicity, and specificity studies. PMID:27437460

  2. Bioactive Potential of Actinomycetes from Less Explored Ecosystems against Mycobacterium tuberculosis and Other Nonmycobacterial Pathogens

    PubMed Central

    Venugopal, Gopikrishnan; Subramaniam, Balaji; Ramasamy, Balagurunathan

    2014-01-01

    Bioactive potential of actinomycetes isolated from certain less explored Indian ecosystems against Mycobacterium tuberculosis and other nonmycobacterial pathogens was investigated. Actinomycetes were isolated from the soil samples collected from desert, coffee plantation, rubber forest, and hill area and their cultural and micromorphological characteristics were studied. Crude extracts were prepared by agar surface fermentation and tested against M. tuberculosis isolates by luciferase reporter phage (LRP) assay at 100 µg/mL. Activity against nonmycobacterial pathogens was studied by agar plug method. Totally 54 purified cultures of actinomycetes including 43 Streptomyces and 11 non-Streptomyces were isolated. While screening for antitubercular activity, extracts of 39 actinomycetes showed activity against one or more M. tuberculosis isolates whereas 27 isolates exhibited antagonistic activity against nonmycobacterial pathogens. In particular crude extracts from sixteen actinomycete isolates inhibited all the three M. tuberculosis isolates tested. Findings of the present study concluded that less explored ecosystems investigated in this study are the potential resource for bioactive actinomycetes. Further purification and characterization of active molecule from the potential extracts will pave the way for determination of MIC, toxicity, and specificity studies.

  3. Influence of moisture on the vital activity of actinomycetes in a cultivated low-moor peat soil

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Gryadunova, A. A.; Doroshenko, E. A.; Likhacheva, A. A.; Sudnitsyn, I. I.; Pochatkova, T. N.; Zvyagintsev, D. G.

    2007-05-01

    It was found that the actinomycetal complex of a cultivated low-moor peat soil is characterized by a high population density and diversity of actinomycetes; representatives of eleven genera were isolated from this soil: Streptomyces, Micromonospora, Actinomadura, Saccharopolyspora, Microbispora, Microtetraspora, Streptosporangium, Nocardioides, Saccharomonospora, Kibdelosporangium, and Thermomonospora. Some genera were isolated from the soil under all the studied levels of soil moisture. The so-called rare (rarely occurring) genera (Saccharomonospora, Kibdelosporangium, and Thermomonospora) were isolated upon the low level of soil moisture, which ensured an absence of competition from the more abundant actinomycetes. Spores of all the studied actinomycetes could germinate under the low moisture level (a w = 0.67). The level of moisture a w = 0.98 was found to be optimal for the development of the actinomycetes. The complete cycle of the development of all the actinomycetes up to spore formation occurring was only observed under the high moisture level (a w = 0.98).

  4. A polyphasic taxonomic evaluation of Streptomyces strains isolated from equine placentas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Actinomycete strains isolated from lesions on equine placentas were subjected to polyphasic taxonomic identification. All of the strains were isolated from placentas from horses in Kentucky. On the basis of phylogenetic analysis of 16S rDNA sequences, morphological observations, and the presence o...

  5. Rare actinomycetes Nocardia caishijiensis and Pseudonocardia carboxydivorans as endophytes, their bioactivity and metabolites evaluation.

    PubMed

    Tanvir, Rabia; Sajid, Imran; Hasnain, Shahida; Kulik, Andreas; Grond, Stephanie

    2016-04-01

    Two strains identified as Nocardia caishijiensis (SORS 64b) and Pseudonocardia carboxydivorans (AGLS 2) were isolated as endophytes from Sonchus oleraceus and Ageratum conyzoides respectively. The analysis of their extracts revealed them to be strongly bioactive. The N. caishijiensis extract gave an LC50 of 570 μg/ml(-1) in the brine shrimp cytotoxicity assay and an EC50 of 0.552 μg/ml(-1) in the DPPH antioxidant assay. Antimicrobial activity was observed against Methicillin resistant Staphlococcus aureus (MRSA) and Escherichia coli ATCC 25922 (14 mm), Klebsiella pneumoniae ATCC 706003 (13 mm), S. aureus ATCC 25923 (11 mm) and Candida tropicalis (20 mm). For the extract of P. carboxydivorans the EC50 was 0.670 μg/ml(-1) and it was observed to be more bioactive against Bacillus subtilis DSM 10 ATCC 6051 (21 mm), C. tropicalis (20 mm), S. aureus ATCC 25923 (17 mm), MRSA (17 mm), E. coli K12 (W1130) (16 mm) and Chlorella vulgaris (10 mm). The genotoxicity testing revealed a 20 mm zone of inhibition against the polA mutant strain E. coli K-12 AB 3027 suggesting damage to the DNA and polA genes. The TLC and bioautography screening revealed a diversity of active bands of medium polar and nonpolar compounds. Metabolite analysis by HPLC-DAD via UV/vis spectral screening suggested the possibility of stenothricin and bagremycin A in the mycelium extract of N. caishijiensis respectively. In the broth and mycelium extract of P. carboxydivorans borrelidin was suggested along with α-pyrone. The HPLC-MS revealed bioactive long chained amide derivatives such as 7-Octadecenamide, 9, 12 octadecandienamide. This study reports the rare actinomycetes N. caishijiensis and P. carboxydivorans as endophytes and evaluates their bioactive metabolites. PMID:26946375

  6. Enhanced production of thermostable laccases from a native strain of Pycnoporus sanguineus using central composite design.

    PubMed

    Ramírez-Cavazos, Leticia I; Junghanns, Charles; Nair, Rakesh; Cárdenas-Chávez, Diana L; Hernández-Luna, Carlos; Agathos, Spiros N; Parra, Roberto

    2014-04-01

    The production of thermostable laccases from a native strain of the white-rot fungus Pycnoporus sanguineus isolated in Mexico was enhanced by testing different media and a combination of inducers including copper sulfate (CuSO4). The best conditions obtained from screening experiments in shaken flasks using tomato juice, CuSO4, and soybean oil were integrated in an experimental design. Enhanced levels of tomato juice as the medium, CuSO4 and soybean oil as inducers (36.8% (v/v), 3 mmol/L, and 1% (v/v), respectively) were determined for 10 L stirred tank bioreactor runs. This combination resulted in laccase titer of 143,000 IU/L (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), pH 3.0), which represents the highest activity so far reported for P. sanguineus in a 10-L fermentor. Other interesting media resulting from the screening included glucose-bactopeptone which increased laccase activity up to 20,000 IU/L, whereas the inducers Acid Blue 62 and Reactive Blue 19 enhanced enzyme production in this medium 10 times. Based on a partial characterization, the laccases of this strain are especially promising in terms of thermostability (half-life of 6.1 h at 60 °C) and activity titers. PMID:24711355

  7. Enhanced production of thermostable laccases from a native strain of Pycnoporus sanguineus using central composite design*

    PubMed Central

    Ramírez-Cavazos, Leticia I.; Junghanns, Charles; Nair, Rakesh; Cárdenas-Chávez, Diana L.; Hernández-Luna, Carlos; Agathos, Spiros N.; Parra, Roberto

    2014-01-01

    The production of thermostable laccases from a native strain of the white-rot fungus Pycnoporus sanguineus isolated in Mexico was enhanced by testing different media and a combination of inducers including copper sulfate (CuSO4). The best conditions obtained from screening experiments in shaken flasks using tomato juice, CuSO4, and soybean oil were integrated in an experimental design. Enhanced levels of tomato juice as the medium, CuSO4 and soybean oil as inducers (36.8% (v/v), 3 mmol/L, and 1% (v/v), respectively) were determined for 10 L stirred tank bioreactor runs. This combination resulted in laccase titer of 143 000 IU/L (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), pH 3.0), which represents the highest activity so far reported for P. sanguineus in a 10-L fermentor. Other interesting media resulting from the screening included glucose-bactopeptone which increased laccase activity up to 20 000 IU/L, whereas the inducers Acid Blue 62 and Reactive Blue 19 enhanced enzyme production in this medium 10 times. Based on a partial characterization, the laccases of this strain are especially promising in terms of thermostability (half-life of 6.1 h at 60 °C) and activity titers. PMID:24711355

  8. Design of a Probe for Strain Sensitivity Studies of Critical Current Densities in SC Wires and Tapes

    SciTech Connect

    Dhanaraj, N.; Barzi, E.; Turrioni, D.; Rusy, A.; Lombardo, V.; /Fermilab

    2011-07-01

    The design of a variable-temperature probe used to perform strain sensitivity measurements on LTS wires and HTS wires and tapes is described. The measurements are intended to be performed at liquid helium temperatures (4.2 K). The wire or tape to be measured is wound and soldered on to a helical spring device, which is fixed at one end and subjected to a torque at the free end. The design goal is to be able to achieve {+-} 0.8 % strain in the wire and tape. The probe is designed to carry a current of 2000A.

  9. Improved vertical optical fiber borehole strainmeter design for measuring Earth strain.

    PubMed

    DeWolf, Scott; Wyatt, Frank K; Zumberge, Mark A; Hatfield, William

    2015-11-01

    Fiber-based interferometers provide the means to sense very small displacements over long baselines, and have the advantage of being nearly completely passive in their operation, making them particularly well suited for geophysical applications. A new 250 m, interferometric vertical borehole strainmeter has been developed based completely on passive optical components. Details of the design and deployment at the Piñon Flat Observatory are presented. Power spectra show an intertidal noise level of -130 dB (re. 1 ϵ(2)/Hz), consistent within 1-3 dB between redundant components. Examination of its response to Earth tides and earthquakes relative to the areal strain recorded by an orthogonal pair of collocated, 730 m horizontal laser strainmeters yield a Poisson's ratio for local near surface material of 0.25 that is consistent with previous results. PMID:26628152

  10. Improved vertical optical fiber borehole strainmeter design for measuring Earth strain

    NASA Astrophysics Data System (ADS)

    DeWolf, Scott; Wyatt, Frank K.; Zumberge, Mark A.; Hatfield, William

    2015-11-01

    Fiber-based interferometers provide the means to sense very small displacements over long baselines, and have the advantage of being nearly completely passive in their operation, making them particularly well suited for geophysical applications. A new 250 m, interferometric vertical borehole strainmeter has been developed based completely on passive optical components. Details of the design and deployment at the Piñon Flat Observatory are presented. Power spectra show an intertidal noise level of -130 dB (re. 1 ɛ2/Hz), consistent within 1-3 dB between redundant components. Examination of its response to Earth tides and earthquakes relative to the areal strain recorded by an orthogonal pair of collocated, 730 m horizontal laser strainmeters yield a Poisson's ratio for local near surface material of 0.25 that is consistent with previous results.

  11. Determination of the Residual Anthracene Concentration in Cultures of Haloalkalitolerant Actinomycetes by Excitation Fluorescence, Emission Fluorescence, and Synchronous Fluorescence: Comparative Study.

    PubMed

    Lara-Severino, Reyna Del Carmen; Camacho-López, Miguel Ángel; García-Macedo, Jessica Marlene; Gómez-Oliván, Leobardo M; Sandoval-Trujillo, Ángel H; Isaac-Olive, Keila; Ramírez-Durán, Ninfa

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are compounds that can be quantified by fluorescence due to their high quantum yield. Haloalkalitolerant bacteria tolerate wide concentration ranges of NaCl and pH. They are potentially useful in the PAHs bioremediation of saline environments. However, it is known that salinity of the sample affects fluorescence signal regardless of the method. The objective of this work was to carry out a comparative study based on the sensitivity, linearity, and detection limits of the excitation, emission, and synchronous fluorescence methods, during the quantification of the residual anthracene concentration from the following haloalkalitolerant actinomycetes cultures Kocuria rosea, Kocuria palustris, Microbacterium testaceum, and 4 strains of Nocardia farcinica, in order to establish the proper fluorescence method to study the PAHs biodegrading capacity of haloalkalitolerant actinobacteria. The study demonstrated statistical differences among the strains and among the fluorescence methods regarding the anthracene residual concentration. The results showed that excitation and emission fluorescence methods performed very similarly but sensitivity in excitation fluorescence is slightly higher. Synchronous fluorescence using Δλ = 150 nm is not the most convenient method. Therefore we propose the excitation fluorescence as the fluorescence method to be used in the study of the PAHs biodegrading capacity of haloalkalitolerant actinomycetes. PMID:26925294

  12. Comparative analysis of chemical constituents, antimicrobial and antioxidant activities of ethylacetate extracts of Polygonum cuspidatum and its endophytic actinomycete, Streptomyces sp. A0916.

    PubMed

    Wang, Lei; Qiu, Peng; Long, Xiu-Feng; Zhang, Shuai; Zeng, Zhi-Gang; Tian, Yong-Qiang

    2016-02-01

    The present study investigated the chemical composition of ethylacetate extracts from an endophytic actinomycete Streptomyces sp. A0916 and its host Polygonum cuspidatum. A comparative analysis of the antimicrobial and antioxidant properties of the extracts was also conducted. 32 compounds of P. cuspidatum and 23 compounds of Streptomyces sp. A0916 were isolated and identified by GC/MS. Antimicrobial activities of the extracts were evaluated using eight microbial strains (3 Gram-positive bacteria, 3 Gram-negative bacteria, and 2 fungi). The Streptomyces sp. A0916 extracts showed a wide range of antimicrobial activities and presented greater antimicrobial effectiveness than the P. cuspidatum extracts. The minimum inhibitory concentration (MIC) of Streptomyces sp. A0916 extracts against the ampicillin-resistant strain Enterococcus faecium SIIA843 was 32 μg·mL(-1). Furthermore, the extracts had greater antimicrobial effect against Gram-positive bacteria than Gram-negative bacteria. Finally, the antioxidant activity of the Streptomyces sp. A0916 extracts was equal to that of the P. cuspidatum extracts. In conclusion, our results suggest that the endophytic actinomycetes of the medicinal plants are an important source of bioactive substances. PMID:26968677

  13. Determination of the Residual Anthracene Concentration in Cultures of Haloalkalitolerant Actinomycetes by Excitation Fluorescence, Emission Fluorescence, and Synchronous Fluorescence: Comparative Study

    PubMed Central

    Lara-Severino, Reyna del Carmen; Camacho-López, Miguel Ángel; García-Macedo, Jessica Marlene; Gómez-Oliván, Leobardo M.; Sandoval-Trujillo, Ángel H.; Isaac-Olive, Keila; Ramírez-Durán, Ninfa

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are compounds that can be quantified by fluorescence due to their high quantum yield. Haloalkalitolerant bacteria tolerate wide concentration ranges of NaCl and pH. They are potentially useful in the PAHs bioremediation of saline environments. However, it is known that salinity of the sample affects fluorescence signal regardless of the method. The objective of this work was to carry out a comparative study based on the sensitivity, linearity, and detection limits of the excitation, emission, and synchronous fluorescence methods, during the quantification of the residual anthracene concentration from the following haloalkalitolerant actinomycetes cultures Kocuria rosea, Kocuria palustris, Microbacterium testaceum, and 4 strains of Nocardia farcinica, in order to establish the proper fluorescence method to study the PAHs biodegrading capacity of haloalkalitolerant actinobacteria. The study demonstrated statistical differences among the strains and among the fluorescence methods regarding the anthracene residual concentration. The results showed that excitation and emission fluorescence methods performed very similarly but sensitivity in excitation fluorescence is slightly higher. Synchronous fluorescence using Δλ = 150 nm is not the most convenient method. Therefore we propose the excitation fluorescence as the fluorescence method to be used in the study of the PAHs biodegrading capacity of haloalkalitolerant actinomycetes. PMID:26925294

  14. Chromomycins A2 and A3 from marine actinomycetes with TRAIL resistance-overcoming and Wnt signal inhibitory activities.

    PubMed

    Toume, Kazufumi; Tsukahara, Kentaro; Ito, Hanako; Arai, Midori A; Ishibashi, Masami

    2014-06-01

    A biological screening study of an actinomycetes strain assembly was conducted using a cell-based cytotoxicity assay. The CKK1019 strain was isolated from a sea sand sample. Cytotoxicity-guided fractionation of the CKK1019 strain culture broth, which exhibited cytotoxicity, led to the isolation of chromomycins A2 (1) and A3 (2). 1 and 2 showed potent cytotoxicity against the human gastric adenocarcinoma (AGS) cell line (IC50 1; 1.7 and 2; 22.1 nM), as well as strong inhibitory effects against TCF/β-catenin transcription (IC50 1; 1.8 and 2; 15.9 nM). 2 showed the ability to overcome tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) resistance. To the best of our knowledge, the effects of chromomycins A2 (1) and A3 (2) on TRAIL resistance-overcoming activity, and on the Wnt signaling pathway, have not been reported previously. Thus, 1 and 2 warrant potential drug lead studies in relation to TRAIL-resistant and Wnt signal-related diseases and offer potentially useful chemical probes for investigating TRAIL resistance and the Wnt signaling pathway. PMID:24905484

  15. Characterization of a chitinase from the cellulolytic actinomycete Thermobifida fusca.

    PubMed

    Gaber, Yasser; Mekasha, Sophanit; Vaaje-Kolstad, Gustav; Eijsink, Vincent G H; Fraaije, Marco W

    2016-09-01

    Thermobifida fusca is a well-known cellulose-degrading actinomycete, which produces various glycoside hydrolases for this purpose. However, despite the presence of putative chitinase genes in its genome, T. fusca has not been reported to grow on chitin as sole carbon source. In this study, a gene encoding a putative membrane-anchored GH18 chitinase (Tfu0868) from T. fusca has been cloned and overexpressed in Escherichia coli. The protein was produced as SUMO fusion protein and, upon removal of the SUMO domain, soluble pure TfChi18A was obtained with yields typically amounting to 150mg per litre of culture. The enzyme was found to be relatively thermostable (apparent Tm=57.5°C) but not particularly thermoactive, the optimum temperature being 40-45°C. TfChi18A bound to α- and β-chitin and degraded both these substrates. Interestingly, activity towards colloidal chitin was minimal and in this case, substrate inhibition was observed. TfChi18A also cleaved soluble chito-oligosaccharides and showed a clear preference for substrates having five sugars or more. While these results show that TfChi18A is a catalytically competent GH18 chitinase, the observed catalytic rates were low compared to those of well-studied GH18 chitinases. This suggests that TfChi18A is not a true chitinase and not likely to endow T. fusca with the ability to grow on chitin. PMID:27108953

  16. Actinomycetes from Red Sea Sponges: Sources for Chemical and Phylogenetic Diversity

    PubMed Central

    Abdelmohsen, Usama Ramadan; Yang, Chen; Horn, Hannes; Hajjar, Dina; Ravasi, Timothy; Hentschel, Ute

    2014-01-01

    The diversity of actinomycetes associated with marine sponges collected off Fsar Reef (Saudi Arabia) was investigated in the present study. Forty-seven actinomycetes were cultivated and phylogenetically identified based on 16S rRNA gene sequencing and were assigned to 10 different actinomycete genera. Eight putatively novel species belonging to genera Kocuria, Mycobacterium, Nocardia, and Rhodococcus were identified based on sequence similarity values below 98.2% to other 16S rRNA gene sequences available in the NCBI database. PCR-based screening for biosynthetic genes including type I and type II polyketide synthases (PKS-I, PKS-II) as well as nonribosomal peptide synthetases (NRPS) showed that 20 actinomycete isolates encoded each at least one type of biosynthetic gene. The organic extracts of nine isolates displayed bioactivity against at least one of the test pathogens, which were Gram-positive and Gram-negative bacteria, fungi, human parasites, as well as in a West Nile Virus protease enzymatic assay. These results emphasize that marine sponges are a prolific resource for novel bioactive actinomycetes with potential for drug discovery. PMID:24824024

  17. Phylogenetic characterization of culturable actinomycetes associated with the mucus of the coral Acropora digitifera from Gulf of Mannar.

    PubMed

    Nithyanand, Paramasivam; Manju, Sivalingam; Karutha Pandian, Shunmugiah

    2011-01-01

    The marine environment is a virtually untapped source of novel actinomycete diversity and its metabolites. Investigating the diversity of actinomycetes in other marine macroorganisms, like seaweeds and sponges, have resulted in isolation of novel bioactive metabolites. Actinomycetes diversity associated with corals and their produced metabolites have not yet been explored. Hence, in this study we attempted to characterize the culturable actinomycetes population associated with the coral Acropora digitifera. Actinomycetes were isolated from the mucus of the coral wherein the actinomycetes count was much higher when compared with the surrounding seawater and sediment. Actinobacteria-specific 16S rRNA gene primers were used for identifying the isolates at the molecular level in addition to biochemical tests. Amplified ribosomal DNA restriction analysis using three restriction enzymes revealed several polymorphic groups within the isolates. Sequencing and blast analysis of the isolates revealed that some isolates had only 96.7% similarity with its nearest match in GenBank indicating that they may be novel isolates at the species level. The isolated actinomycetes exhibited good antibacterial activity against various human pathogens. This study offers for the first time a prelude about the unexplored culturable actinomycetes diversity associated with a scleractinian coral and their bioactive capabilities. PMID:21105906

  18. Ecological and Taxonomic Features of Actinomycetal Complexes in Soils of the Lake Elton Basin

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Dubrova, M. S.; Kuznetsova, A. I.; Gracheva, T. A.; Manucharova, N. A.; Zvyagintsev, D. G.

    2016-02-01

    In the sor (playa) solonchaks of chloride and sulfate-chloride salinity (the content of readily soluble salts is 0.9-1.0%) in the delta of the Khara River discharging into Lake Elton, the number of mycelial actinobacteria (actinomycetes) is low ((2-3) × 103 CFU/g of soil). At a distance from the water's edge, these soils are substituted for the light chestnut ones, for which an elevated number of actinomycetes (an order of magnitude higher than in the sor solonchaks) and a wider generic spectrum are characteristic. The actinomycetal complex is included the Streptomyces and Micromonospora genera, whereas in the sor solonchaks around the lake, representatives of Micromonospora were not found.

  19. Actinomycetal complexes in drained peat soils of the taiga zone upon pyrogenic succession

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Glushkova, N. A.; Bannikov, M. V.; Shvarov, A. P.; Pozdnyakov, A. I.; Zvyagintsev, D. G.

    2008-04-01

    The number and diversity of actinomycetes in peat soils vary in dependence on the stage of pyrogenic succession. In the cultivated peat soil, the number of actinomycetes after fires decreases by three-four times, mainly at the expense of acidophilic and neutrophilic groups. An increase in the number of mycelial prokaryotes (at the expense of alkaliphilic forms) is seen on the fifth year of functioning of the pyrogenic peat soil. The species diversity of streptomycetes in peat soils also decreases after fires. An increase in the range of streptomycetal species at the expense of neutrophilic and alkaliphilic forms takes place on the fifth year of the pyrogenic succession. Parameters of the actinomycetal complex—the population density, species composition, and ecological features—are the criteria whose changes allow us to judge the state of peat soils in the course of their pyrogenic succession.

  20. A stem design change to reduce peak cement strains at the tip of cemented total hip arthroplasty.

    PubMed

    Estok, D M; Harris, W H

    2000-08-01

    A series of 3-dimensional finite element models was created to assess different designs of the tip of the stems of cemented femoral components of total hip arthroplasty that would decrease the peak axial tensile cement strains developed near the tip. Features of stem design that would facilitate positioning the femoral component in a neutral position centered in uniform cement mantle of adequate thickness also were evaluated. These studies showed that a stem that had a narrow tip profile that would accept an externally applied polymethyl methacrylate centralizer shaped similar to a napkin ring and had a gradual transition zone to join the body of the implant achieved these objectives. Such a combination resulted in the reduction of the peak axial strains to less than half the magnitude of the peak strains around a conventional tip (830 vs 1,868 microstrain). The reduction in peak axial strains was to one third the magnitude of the strains developed adjacent to a stem with a hole drilled into the tip to accept the commonly used fin-type polymethyl methacrylate centralizer (830 vs 2,466 microstrain). These goals were achieved because a stem that is designed to accept a napkin ring-style centralizer i) has a lower bending stiffness at the tip of the implant, ii) allows room for a thicker cement mantle, and iii) avoids creating a stress riser adjacent to the edge of the drill hole. The peak cement strains adjacent to a stem of this design are well below the endurance limit of cement as long as the transition zone where the narrow tip meets the body of the implant is gradual. PMID:10959996

  1. Analysis of coenzyme A activated compounds in actinomycetes.

    PubMed

    Cabruja, Matías; Lyonnet, Bernardo Bazet; Millán, Gustavo; Gramajo, Hugo; Gago, Gabriela

    2016-08-01

    Acyl-CoAs are crucial compounds involved in essential metabolic pathways such as the Krebs cycle and lipid, carbohydrate, and amino acid metabolisms, and they are also key signal molecules involved in the transcriptional regulation of lipid biosynthesis in many organisms. In this study, we took advantage of the high selectivity of mass spectrometry and developed an ion-pairing reverse-phase high-pressure liquid chromatography electrospray ionization high-resolution mass spectrometry (IP-RP-HPLC/ESI-HRMS) method to carry on a comprehensive analytical determination of the wide range of fatty acyl-CoAs present in actinomycetes. The advantage of using a QTOF spectrometer resides in the excellent mass accuracy over a wide dynamic range and measurements of the true isotope pattern that can be used for molecular formula elucidation of unknown analytes. As a proof of concept, we used this assay to determine the composition of the fatty acyl-CoA pools in Mycobacterium, Streptomyces, and Corynebacterium species, revealing an extraordinary difference in fatty acyl-CoA amounts and species distribution between the three genera and between the two species of mycobacteria analyzed, including the presence of different chain-length carboxy-acyl-CoAs, key substrates of mycolic acid biosynthesis. The method was also used to analyze the impact of two fatty acid synthase inhibitors on the acyl-CoA profile of Mycobacterium smegmatis, which showed some unexpected low levels of C24 acyl-CoAs in the isoniazid-treated cells. This robust, sensitive, and reliable method should be broadly applicable in the studies of the wide range of bacteria metabolisms in which acyl-CoA molecules participate. PMID:27270600

  2. Effect of cadmium on soil bacteria and actinomycetes

    SciTech Connect

    Williams, S.E.; Wollum, A.G. II

    1981-04-01

    Soil procaryotic populations were evaluated from a soybean field (Glycine max L.) that had been amended 3 years previously with Cd (as CdCl/sub 2/ 2 1/2H/sub 2/O) at rates corresponding to 0, 6, 22, and 40 kg Cd/ha. Replicate aliquots of soil suspensions from the treated plots were plated on media containing increasing concentrations of Cd. This was done to determine if soil bacteria and actinomycetes (procaryotes) that were tolerant of Cd had developed in Cd-treated soils. It was found that the level of DTPA-TEA extractable soil Cd had no influence on the development of Cd-tolerant soil populations on media amended with Cd. Rather, it was found that low levels of media Cd retarded procaryote growth, whereas high levels did not. This also occurred regardless of the level of soil extractable Cd. Soil moisture at the time of sampling was found to be inversely related to procaryote numbers on media containing 0 ppM Cd and directly related on media containing 10, 20, and 40 ppM Cd. On media containing 5 ppM Cd, numbers of soil organisms were low with respect to the control and other Cd media levels and had no relationship to soil moisture. Growth rate constants of 58 pure cultured bacteria were determined at Cd concentrations of 0, 5, 10, 20, and 40 ppM in liquid media. The organisms exhibited tolerant, intolerant, and stimulated responses of Cd; however, 50% were intolerant to 5 ppM Cd but tolerant at concentrations > 5 ppM.

  3. Design of a Small-Molecule Entry Inhibitor with Activity against Primary Measles Virus Strains

    PubMed Central

    Plemper, Richard K.; Doyle, Joshua; Sun, Aiming; Prussia, Andrew; Cheng, Li-Ting; Rota, Paul A.; Liotta, Dennis C.; Snyder, James P.; Compans, Richard W.

    2005-01-01

    The incidence of measles virus (MV) infection has been significantly reduced in many nations through extensive vaccination; however, the virus still causes significant morbidity and mortality in developing countries. Measles outbreaks also occur in some developed countries that have failed to maintain high vaccine coverage rates. While vaccination is essential in preventing the spread of measles, case management would greatly benefit from the use of therapeutic agents to lower morbidity. Thus, the development of new therapeutic strategies is desirable. We previously reported the generation of a panel of small-molecule MV entry inhibitors. Here we show that our initial lead compound, although providing proof of concept for our approach, has a short half-life (<16 h) under physiological conditions. In order to combine potent antiviral activity with increased compound stability, a targeted library of candidate molecules designed on the structural basis of the first lead has been synthesized and tested against MV. We have identified an improved lead with low toxicity and high stability (half-life ≫ 16 h) that prevents viral entry and hence infection. This compound shows high MV specificity and strong activity (50% inhibitory concentration = 0.6 to 3.0 μM, depending on the MV genotype) against a panel of wild-type MV strains representative of viruses that are currently endemic in the field. PMID:16127050

  4. Geomechanical Modeling to Predict Wellbore Stresses and Strains for the Design of Wellbore Seal Repair Materials

    NASA Astrophysics Data System (ADS)

    Gomez, S. P.; Sobolik, S. R.; Matteo, E. N.; Dewers, T. A.; Taha, M. R.; Stormont, J. C.

    2013-12-01

    A critical aspect of designing effective wellbore seal repair materials is predicting thermo-mechanical perturbations in local stress that can compromise seal integrity. For the DOE-NETL project 'Wellbore Seal Repair Using Nanocomposite Materials,' we are especially interested in the stress-strain history of abandoned wells, as well as changes in local pressure, stress, and temperature conditions that accompany carbon dioxide injection or brine extraction. Building on existing thermo-hydro-mechanical (THM) finite element modeling of wellbore casings subject to significant tensile and shear loads, we advance a conceptual and numerical methodology to assess responses of annulus cement and casing. Bench-scale models complement bench-top experiments of an integrated seal system in an idealized scaled wellbore mock-up being used to test candidate seal repair materials. Field scale models use the stratigraphy from a pilot CO2 injection operation to estimate the necessary mechanical properties needed for a successful repair material. We report on approaches used for adapting existing wellbore models and share preliminary results of field scale models. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND Number: 2013-6241A.

  5. Crystallochemical transformation of phyllosilicates under the impact of cyanobacteria and actinomycetes

    NASA Astrophysics Data System (ADS)

    Chizhikova, N. P.; Omarova, E. O.; Lobakova, E. S.; Zenova, G. M.; Manucharov, A. S.

    2009-01-01

    The transformation of the crystallochemical structure of phyllosilicates (vermiculite and biotite) under the impact of growing cyanobacterial and actinomycetal associations, as well as monocultures of cyanobacteria and actinomycetes, has been studied. The character of the mineral transformation depends on their crystallochemical structure and the type of biota. The most significant changes take place in the contact zone between minerals and microbial associations; the effect of microbial monocultures is smaller. The transformation of biotite proceeds via the stage of ordered mica-vermiculite (smectite) neoformation (rectorite); the destruction of vermiculite has been identified.

  6. Utilization of Genomic Variations Among Xylella fastidiosa Strains for Improved Diagnostic Design

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Gram-negative, xylem-limited phytopathogenic bacterium Xylella fastidiosa causes economically important diseases in grapevine, citrus and many other plant species. Our recent whole genome comparative analysis of the four sequenced strains has identified genomic variation among these strains. The...

  7. Alkaloids from the mangrove-derived actinomycete Jishengella endophytica 161111.

    PubMed

    Wang, Pei; Kong, Fandong; Wei, Jingjing; Wang, Yi; Wang, Wei; Hong, Kui; Zhu, Weiming

    2014-01-01

    A new alkaloid, 2-(furan-2-yl)-6-(2S,3S,4-trihydroxybutyl)pyrazine (1), along with 12 known compounds, 2-(furan-2-yl)-5-(2S,3S,4-trihydroxybutyl)pyrazine (2), (S)-4-isobutyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (3), (S)-4-isopropyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (4), (4S)-4-(2-methylbutyl)-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (5), (S)-4-benzyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (6), flazin (7), perlolyrine (8), 1-hydroxy-β-carboline (9), lumichrome (10), 1H-indole-3-carboxaldehyde (11), 2-hydroxy-1-(1H-indol-3-yl)ethanone (12), and 5-(methoxymethyl)-1H-pyrrole-2-carbaldehyde (13), were isolated and identified from the fermentation broth of an endophytic actinomycetes, Jishengella endophytica 161111. The new structure 1 and the absolute configurations of 2-6 were determined by spectroscopic methods, J-based configuration analysis (JBCA) method, lactone sector rule, and electronic circular dichroism (ECD) calculations. Compounds 8-11 were active against the influenza A virus subtype H1N1 with IC50 and selectivity index (SI) values of 38.3(±1.2)/25.0(±3.6)/39.7(±5.6)/45.9(±2.1) μg/mL and 3.0/16.1/3.1/11.4, respectively. The IC50 and SI values of positive control, ribavirin, were 23.1(±1.7) μg/mL and 32.2, respectively. The results showed that compound 9 could be a promising new hit for anti-H1N1 drugs. The absolute configurations of 2-5, 13C nuclear magnetic resonance (NMR) data and the specific rotations of 3-6 were also reported here for the first time. PMID:24451190

  8. Alkaloids from the Mangrove-Derived Actinomycete Jishengella endophytica 161111

    PubMed Central

    Wang, Pei; Kong, Fandong; Wei, Jingjing; Wang, Yi; Wang, Wei; Hong, Kui; Zhu, Weiming

    2014-01-01

    A new alkaloid, 2-(furan-2-yl)-6-(2S,3S,4-trihydroxybutyl)pyrazine (1), along with 12 known compounds, 2-(furan-2-yl)-5-(2S,3S,4-trihydroxybutyl)pyrazine (2), (S)-4-isobutyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (3), (S)-4-isopropyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (4), (4S)-4-(2-methylbutyl)-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (5), (S)-4-benzyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (6), flazin (7), perlolyrine (8), 1-hydroxy-β-carboline (9), lumichrome (10), 1H-indole-3-carboxaldehyde (11), 2-hydroxy-1-(1H-indol-3-yl)ethanone (12), and 5-(methoxymethyl)-1H-pyrrole-2-carbaldehyde (13), were isolated and identified from the fermentation broth of an endophytic actinomycetes, Jishengella endophytica 161111. The new structure 1 and the absolute configurations of 2–6 were determined by spectroscopic methods, J-based configuration analysis (JBCA) method, lactone sector rule, and electronic circular dichroism (ECD) calculations. Compounds 8–11 were active against the influenza A virus subtype H1N1 with IC50 and selectivity index (SI) values of 38.3(±1.2)/25.0(±3.6)/39.7(±5.6)/45.9(±2.1) μg/mL and 3.0/16.1/3.1/11.4, respectively. The IC50 and SI values of positive control, ribavirin, were 23.1(±1.7) μg/mL and 32.2, respectively. The results showed that compound 9 could be a promising new hit for anti-H1N1 drugs. The absolute configurations of 2–5, 13C nuclear magnetic resonance (NMR) data and the specific rotations of 3–6 were also reported here for the first time. PMID:24451190

  9. Anthracimycin, a potent anthrax antibiotic from a marine-derived actinomycete.

    PubMed

    Jang, Kyoung Hwa; Nam, Sang-Jip; Locke, Jeffrey B; Kauffman, Christopher A; Beatty, Deanna S; Paul, Lauren A; Fenical, William

    2013-07-22

    Licensed to kill: A new antibiotic, anthracimycin (see scheme), produced by a marine-derived actinomycete in saline culture, shows significant activity toward Bacillus anthracis, the bacterial pathogen responsible for anthrax infections. Chlorination of anthracimycin gives a dichloro derivative that retains activity against Gram-positive bacteria, such as anthrax, but also shows activity against selected Gram-negative bacteria. PMID:23776159

  10. Population densities and genetic diversity of actinomycetes associated to the rhizosphere of Theobroma cacao

    PubMed Central

    Barreto, Tâmara R.; da Silva, Augusto C.M.; Soares, Ana Cristina F.; de Souza, Jorge T.

    2008-01-01

    In spite of the acknowledged importance of growth-promoting bacteria, only a reduced number of studies were conducted with these microorganisms on Theobroma cacao. The objectives of this work were to study the population densities and genetic diversity of actinomycetes associated with the rhizosphere of cacao as a first step in their application in plant growth promotion and biological control. The populations densities of actinomycetes in soil and cacao roots were similar, with mean values of 1,0 x 106 CFU/g and 9,6 x 105 CFU/g, respectively. All isolates selected and used in this study were identified through sequencing analyses of a fragment of the rpoB gene that encodes the β-subunit of the RNA polymerase as species of the genus Streptomyces. In vitro cellulolytic, xilanolytic and chitinolytic activity, indolacetic acid production and phosphate solubilization activities were observed in most of the isolates tested. The data obtained in this study demonstrate that actinomycetes account for a higher percentage of the total population of culturable bacteria in soil than on cacao roots. Additionally, actinomycetes from the cacao rhizosphere are genetically diverse and have potential applications as agents of growth promotion. PMID:24031247

  11. Adsorption by design: Tuning atom-graphene van der Waals interactions via mechanical strain

    NASA Astrophysics Data System (ADS)

    Nichols, Nathan S.; Del Maestro, Adrian; Wexler, Carlos; Kotov, Valeri N.

    2016-05-01

    We aim to understand how the van der Waals force between neutral adatoms and a graphene layer is modified by uniaxial strain and electron correlation effects. A detailed analysis is presented for three atoms (He, H, and Na) and graphene strain ranging from weak to moderately strong. We show that the van der Waals potential can be significantly enhanced by strain, and present applications of our results to the problem of elastic scattering of atoms from graphene. In particular, we find that quantum reflection can be significantly suppressed by strain, meaning that dissipative inelastic effects near the surface become of increased importance. Furthermore, we introduce a method to independently estimate the Lennard-Jones parameters used in an effective model of He interacting with graphene, and determine how they depend on strain. At short distances, we find that strain tends to reduce the interaction strength by pushing the location of the adsorption potential minima to higher distances above the deformed graphene sheet. This opens up the exciting possibility of mechanically engineering an adsorption potential, with implications for the formation and observation of anisotropic low-dimensional superfluid phases.

  12. Innovative IPV from attenuated Sabin poliovirus or newly designed alternative seed strains.

    PubMed

    Hamidi, Ahd; Bakker, Wilfried A M

    2012-11-01

    This article gives an overview of the patent literature related to innovative inactivated polio vaccine (i-IPV) based on using Sabin poliovirus strains and newly developed alternative recombinant poliovirus strains. This innovative approach for IPV manufacturing is considered to attribute to the requirement for affordable IPV in the post-polio-eradication era, which is on the horizon. Although IPV is a well-established vaccine, the number of patent applications in this field was seen to have significantly increased in the past decade. Currently, regular IPV appears to be too expensive for universal use. Future affordability may be achieved by using alternative cell lines, alternative virus seed strains, improved and optimized processes, dose sparing, or the use of adjuvants. A relatively short-term option to achieve cost-price reduction is to work on regular IPV, using wild-type poliovirus strains, or on Sabin-IPV, based on using attenuated poliovirus strains. This price reduction can be achieved by introducing efficiency in processing. There are also multiple opportunities to work on dose sparing, for example, by using adjuvants or fractional doses. Renewed interest in this field was clearly reflected in the number and diversity of patent applications. In a later stage, several innovative approaches may become even more attractive, for example the use of recombinant virus strains or even a totally synthetic vaccine. Currently, such work is mainly carried out by research institutes and universities and therefore clinical data are not available. PMID:24236927

  13. Strain measurement of objects subjected to aerodynamic heating using digital image correlation: experimental design and preliminary results.

    PubMed

    Pan, Bing; Jiang, Tianyun; Wu, Dafang

    2014-11-01

    In thermomechanical testing of hypersonic materials and structures, direct observation and quantitative strain measurement of the front surface of a test specimen directly exposed to severe aerodynamic heating has been considered as a very challenging task. In this work, a novel quartz infrared heating device with an observation window is designed to reproduce the transient thermal environment experienced by hypersonic vehicles. The specially designed experimental system allows the capture of test article's surface images at various temperatures using an optical system outfitted with a bandpass filter. The captured images are post-processed by digital image correlation to extract full-field thermal deformation. To verify the viability and accuracy of the established system, thermal strains of a chromiumnickel austenite stainless steel sample heated from room temperature up to 600 °C were determined. The preliminary results indicate that the air disturbance between the camera and the specimen due to heat haze induces apparent distortions in the recorded images and large errors in the measured strains, but the average values of the measured strains are accurate enough. Limitations and further improvements of the proposed technique are discussed. PMID:25430144

  14. Isolation and characterization of Streptomyces spp. strains F-6 and F-7 capable of decomposing alkali lignin.

    PubMed

    Yang, Y S; Zhou, J T; Lu, H; Yuan, Y L; Zhao, L H

    2012-12-01

    Biodegradation and bioconversion of lignin are the result of the combined action of fungi, bacteria and actinomycetes. Through screening from forest soil, two novel isolated actinomycete strains were identified as Streptomyces spp. strains F-6 and F-7 by their morphology, cultural characteristics and high homology to the 16S rRNA gene. Both strains possessed laccase and manganese peroxidase activities. Laccase activity produced by strain F-6 was up to 935.4 U g(-1) dry cell weight. More than 50% of alkali lignin was removed by strains F-6 and F-7 in 12 days of incubation. GC-MS analysis of the biodegraded products showed strain F-6 converted lignin into phenol and broken phenol compounds. The two strains could co-culture with white-rot fungus, and the combined actinonycete-fungus system decomposed alkali lignin effectively. PMID:23437660

  15. Enumerating actinomycetes in compost bioaerosols at source—Use of soil compost agar to address plate 'masking'

    NASA Astrophysics Data System (ADS)

    Taha, M. P. M.; Drew, G. H.; Tamer Vestlund, A.; Aldred, D.; Longhurst, P. J.; Pollard, S. J. T.

    Actinomycetes are the dominant bacteria isolated from bioaerosols sampled at composting facilities. Here, a novel method for the isolation of actinomycetes is reported, overcoming masking of conventional agar plates, as well as reducing analysis time and costs. Repeatable and reliable actinomycetes growth was best achieved using a soil compost media at an incubation temperature of 44 °C and 7 days' incubation. The results are of particular value to waste management operators and their advisors undertaking regulatory risk assessments that support environmental approvals for compost facilities.

  16. A mixed community of actinomycetes produce multiple antibiotics for the fungus farming ant Acromyrmex octospinosus

    PubMed Central

    2010-01-01

    Background Attine ants live in an intensely studied tripartite mutualism with the fungus Leucoagaricus gongylophorus, which provides food to the ants, and with antibiotic-producing actinomycete bacteria. One hypothesis suggests that bacteria from the genus Pseudonocardia are the sole, co-evolved mutualists of attine ants and are transmitted vertically by the queens. A recent study identified a Pseudonocardia-produced antifungal, named dentigerumycin, associated with the lower attine Apterostigma dentigerum consistent with the idea that co-evolved Pseudonocardia make novel antibiotics. An alternative possibility is that attine ants sample actinomycete bacteria from the soil, selecting and maintaining those species that make useful antibiotics. Consistent with this idea, a Streptomyces species associated with the higher attine Acromyrmex octospinosus was recently shown to produce the well-known antifungal candicidin. Candicidin production is widespread in environmental isolates of Streptomyces, so this could either be an environmental contaminant or evidence of recruitment of useful actinomycetes from the environment. It should be noted that the two possibilities for actinomycete acquisition are not necessarily mutually exclusive. Results In order to test these possibilities we isolated bacteria from a geographically distinct population of A. octospinosus and identified a candicidin-producing Streptomyces species, which suggests that they are common mutualists of attine ants, most probably recruited from the environment. We also identified a Pseudonocardia species in the same ant colony that produces an unusual polyene antifungal, providing evidence for co-evolution of Pseudonocardia with A. octospinosus. Conclusions Our results show that a combination of co-evolution and environmental sampling results in the diversity of actinomycete symbionts and antibiotics associated with attine ants. PMID:20796277

  17. Finite element modeling to determine thermal residual strain distribution of bonded composite repairs for structural health monitoring design

    NASA Astrophysics Data System (ADS)

    Baker, Wayne; Jones, Rhys; Davis, Claire; Galea, Stephen C.

    2002-11-01

    The economic implication of fleet upgrades, particularly in Australia with military aircraft such as the F-111 and F/A-18, has led to an increasing reliance on composite repair technology to address fatigue and corrosion-affected aircraft components. The increasing use of such repairs has led to a research effort to develop various in-situ health monitoring systems that may be incorporated with a repair. This paper reports on the development of a theoretical methodology that uses finite element analysis (FEA) to model the strain profiles which optical sensors, on or within the patch, will be exposed to under various operational scenarios, including load and disbond. Numerical techniques are then used to predict the fibre Bragg grating (FBG) reflections which occur with these strain profiles. The quality of these reflection are a key consideration when designing FBG based structural health monitoring (SHM) systems. This information can be used to optimise the location of both surface mounted, and embedded sensors, and determine feasibility of SHM system design. Research was conducted into the thermal residual strain (TRS) within the patch. A finite element study revealed the presence of significant thermal residual strain gradients along the surface of the tapered region of the patch. As Bragg gratings are particularly sensitive to strain gradients, (producing a result similar to a chirped grating) the strain gradient on the composite at potential sensor locations both under load, and in the event of disbond was considered. A sufficiently high gradient leads to an altered Bragg reflection. These spurious reflections need to be considered, and theoretically obtained reflections can provide information to allow for load scenarios where the Bragg shift is not a smooth, well defined peak. It can also be shown that embedded fibres offer a higher average thermal residual strain reading, while being subject to a much lower strain gradient. This particularly favors the

  18. Microbispora sp. LGMB259 endophytic actinomycete isolated from Vochysia divergens (Pantanal, Brazil) producing β-carbolines and indoles with biological activity.

    PubMed

    Savi, Daiani C; Shaaban, Khaled A; Vargas, Nathalia; Ponomareva, Larissa V; Possiede, Yvelise M; Thorson, Jon S; Glienke, Chirlei; Rohr, Jürgen

    2015-03-01

    Endophytic actinomycetes encompass bacterial groups that are well known for the production of a diverse range of secondary metabolites. Vochysia divergens is a medicinal plant, common in the "Pantanal" region (Brazil) and was focus of many investigations, but never regarding its community of endophytic symbionts. During a screening program, an endophytic strain isolated from the V. divergens, was investigated for its potential to show biological activity. The strain was characterized as Microbispora sp. LGMB259 by spore morphology and molecular analyze using nucleotide sequence of the 16S rRNA gene. Strain LGMB259 was cultivated in R5A medium producing metabolites with significant antibacterial activity. The strain produced 4 chemically related β-carbolines, and 3 Indoles. Compound 1-vinyl-β-carboline-3-carboxylic acid displayed potent activity against the Gram-positive bacterial strains Micrococcus luteus NRRL B-2618 and Kocuria rosea B-1106, and was highly active against two human cancer cell lines, namely the prostate cancer cell line PC3 and the non-small-cell lung carcinoma cell line A549, with IC50 values of 9.45 and 24.67 µM, respectively. 1-Vinyl-β-carboline-3-carboxylic acid also showed moderate activity against the yeast Saccharomyces cerevisiae ATCC204508, as well as the phytopathogenic fungi Phyllosticta citricarpa LGMB06 and Colletotrichum gloeosporioides FDC83. PMID:25385358

  19. Microbispora sp. LGMB259 Endophytic Actinomycete Isolated from Vochysia divergens (Pantanal, Brazil) Producing β-Carbolines and Indoles with Biological Activity

    PubMed Central

    Savi, Daiani C.; Shaaban, Khaled A.; Vargas, Nathalia; Ponomareva, Larissa V.; Possiede, Yvelise M.; Thorson, Jon S.; Glienke, Chirlei; Rohr, Jürgen

    2014-01-01

    Endophytic actinomycetes encompass bacterial groups that are well known for the production of a diverse range of secondary metabolites. Vochysia divergens is a medicinal plant, common in the “Pantanal” region (Brazil) and was focus of many investigations, but never regarding its community of endophytic symbionts. During a screening program, an endophytic strain isolated from the V. divergens, was investigated for its potential to show biological activity. The strain was characterized as Microbispora sp. LGMB259 by spore morphology and molecular analyze using nucleotide sequence of the 16S rRNA gene. Strain LGMB259 was cultivated in R5A medium producing metabolites with significant antibacterial activity. The strain produced 4 chemically related β-carbolines, and 3 Indoles. Compound 1-Vinyl-β-carboline-3-carboxylic acid displayed potent activity against the Gram-positive bacterial strains Micrococcus luteus NRRL B-2618 and Kocuria rosea B-1106, and was highly active against two human cancer cell lines, namely the prostate cancer cell line PC3 and the non-small-cell lung carcinoma cell line A549, with IC50 values of 9.45 and 24.67 µM, respectively. 1-Vinyl-β-carboline-3-carboxylic acid also showed moderate activity against the yeast Saccharomyces cerevisiae ATCC204508, as well as the phytopathogenic fungiPhyllosticta citricarpa LGMB06 and Colletotrichum gloeosporioides FDC83. PMID:25385358

  20. Cryogenic strain gage techniques used in force balance design for the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Ferris, A. T.

    1986-01-01

    A force balance is a strain gage transducer used in wind tunnels to measure the forces and moments on aerodynamic models. Techniques have been established for temperature-compensation of force balances to allow their use over the operating temperature range of a cryogenic wind tunnel (-190C to 60C) without thermal control. This was accomplished by using a patented strain gage matching process to minimize inherent thermal differences, and a thermal compensation procedure to reduce the remaining thermally-induced outputs to acceptable levels. A method of compensating for mechanical movement of the axial force measuring beam caused by thermally-induced stresses under transient temperatures was also included.

  1. Computer Simulation of Stress-Strain State of Oil Gathering Pipeline Designed for Ugut Field

    NASA Astrophysics Data System (ADS)

    Burkov, P. V.; Burkova, S. P.; Samigullin, V. D.

    2016-04-01

    The paper presents the stress and strain state modeling of infield pipeline in Ugut oil field. The finite element models of the stress field distribution in the pipeline wall are presented in this paper. The attention is paid to the pipeline reliability under stress conditions induced by the internal pressure and external compressive or tensile loads.

  2. Designing acoustic-electric strain-gauge converters for sensitive diaphragm elements

    NASA Astrophysics Data System (ADS)

    Chernyak, M. G.; Kovalenko, T. V.

    Analytic expressions and nomograms are obtained to estimate the sensitivity of differential acoustic-electric measuring pressure converter with an error no more than 5% and to choose such an arrangement of strain-gauge converters on its sensitive diaphragm element that would ensure an additive temperature error of the measuring pressure converter less than 10-4 K-1

  3. General Strain Theory as a Basis for the Design of School Interventions

    ERIC Educational Resources Information Center

    Moon, Byongook; Morash, Merry

    2013-01-01

    The research described in this article applies general strain theory to identify possible points of intervention for reducing delinquency of students in two middle schools. Data were collected from 296 youths, and separate negative binomial regression analyses were used to identify predictors of violent, property, and status delinquency. Emotional…

  4. Sensitivity of Various Bacteria, Including Actinomycetes, and Fungi to Cadmium and the Influence of pH on Sensitivity

    PubMed Central

    Babich, H.; Stotzky, G.

    1977-01-01

    A variety of microorganisms, including gram-negative and gram-positive eubacteria, actinomycetes, yeasts, and filamentous fungi, were tested for their sensitivity to cadmium (Cd). In general, the actinomycetes were more tolerant to Cd than were the eubacteria; gram-negative eubacteria were more tolerant to Cd than were gram-positive eubacteria. The period of exponential growth of the eubacteria and actinomycetes was extended in the presence of Cd. Wide extremes in sensitivity to Cd were noted among the fungi; there was no correlation between the class of fungus and tolerance to Cd. Fungal sporulation was more sensitive to Cd than was mycelial growth, as spore formation was inhibited at Cd concentrations that were noninhibitory to mycelial proliferation. The toxicity of Cd to the eubacteria, actinomycetes, and fungi appeared to be pH dependent, as toxicity was generally potentiated at pH 8 or 9. PMID:16345227

  5. Presence, molecular characteristics and geosmin producing ability of actinomycetes isolated from South Korean terrestrial and aquatic environments.

    PubMed

    Lee, Gyu-Cheol; Kim, Yun S; Kim, Min-Jeong; Oh, Sung-Ae; Choi, Ilhwan; Choi, Jaewon; Park, Jong-Geun; Chong, Chom-Kyu; Kim, Yong-Yeon; Lee, Kyeunghee; Lee, Chan Hee

    2011-01-01

    The unpleasant odor of drinking water is one of the major problems in many water utilities in the world. Actinomycetes have long been associated with odorous compounds. Considering the paucity of research on Actinomycetes producing odorous compounds in South Korea, presence of Actinomycetes, their molecular characteristics and ability to produce odorous compounds were investigated in this study. Findings confirmed the presence of Actinomycetes in surface soil, sediment, and water samples from four sites: two artificial lakes [Paldang and Cheongpyeong (CP)], and two streams [Gyeongan (GA) and Yangpyeong]. Surface soil and sediment from CP area had the greatest concentration of Actinomycetes (8.2 x 10(7) and 6.8 x 10(6) colony forming units (CFUs)/gram, dry weight, respectively). When water samples are considered, samples from GA had the highest concentration (1.9 x 10(2) CFU/mL). 16S rRNA sequencing and molecular phylogenetic analysis showed that Streptomyces was the dominant genus (64.1%). In addition, the isolated Actinomycetes synthesized 5.4 ng/L geosmin as demonstrated by thermal desorption unit-gas chromatograph/mass spectrometry analysis. PMID:22049774

  6. Design and implementation of an x-ray strain measurement capability using a rotating anode machine

    SciTech Connect

    Roberts, J.A.; Rangaswamy, P.; Lujan, M. Jr.; Bourke, M.A.M.

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Residual stresses close to the surface can improve the reliability and lifetime of parts for technological applications. X-ray diffraction plays a significant role in gaining an exact knowledge of the stresses at the surface and their depth distribution. An x-ray capability at Los Alamos is key to developing and maintaining industrial collaborations in strain effects. To achieve this goal, the authors implemented a residual strain measuring station on the rotating anode x-ray instrument at the Lujan Center. This capability has been used to investigate residual strains in heat treated automotive components, machining effects on titanium alloys, resistance welded steel joints, titanium matrix fiber reinforced composites, ceramic matrix composites, thin films, and ceramic coatings. The overall objective is to combine both x-ray and neutron diffraction measurements with numerical models (e.g., finite element calculations).

  7. Degradation of 1,4-dioxane by an actinomycete in pure culture.

    PubMed Central

    Parales, R E; Adamus, J E; White, N; May, H D

    1994-01-01

    An actinomycete capable of sustained aerobic growth on 1,4-dioxane was isolated from a dioxane-contaminated sludge samples. The actinomycete, CB1190, grows on 1,4-dioxane as the sole carbon and energy source with a generation time of approximately 30 h. CB1190 degrades 1,4-dioxane at a rate of 0.33 mg of dioxane min-1 mg of protein-1 and mineralizes 59.5% of the dioxane to CO2. CB1190 also grows with other cyclic and linear ethers as the sole carbon and energy sources, including 1,3-dioxane, 2-methyl-1,3-dioxolane, tetrahydrofuran, tetrahydropyran, diethyl ether, and butyl methyl ether. CB1190 is capable of aerobic autotrophic growth on H2 and CO2. PMID:7811088

  8. Volatile terpenes from actinomycetes: a biosynthetic study correlating chemical analyses to genome data.

    PubMed

    Rabe, Patrick; Citron, Christian A; Dickschat, Jeroen S

    2013-11-25

    The volatile terpenes of 24 actinomycetes whose genomes have been sequenced (or are currently being sequenced) were collected by use of a closed-loop stripping apparatus and identified by GC/MS. The analytical data were compared against a phylogenetic analysis of all 192 currently available sequences of bacterial terpene cyclases (excluding geosmin and 2-methylisoborneol synthases). In addition to the several groups of terpenes with known biosynthetic origin, selinadienes were identified as a large group of biosynthetically related sesquiterpenes that are produced by several streptomycetes. The detection of a large number of previously unrecognised side products of known terpene cyclases proved to be particularly important for an in depth understanding of biosynthetic pathways to known terpenes in actinomycetes. Interpretation of the chemical analytical data in the context of the phylogenetic tree of bacterial terpene cyclases pointed to the function of three new enzymes: (E)-β-caryophyllene synthase, selina-3,7(11)-diene synthase and aristolochene synthase. PMID:24243698

  9. Resistance to thiostrepton, siomycin, and sporangiomycin in actinomycetes that produce them.

    PubMed Central

    Thompson, J; Cundliffe, E

    1980-01-01

    The antibiotics thiostrepton, siomycin, and sporangiomycin are closely related both in structure and in mode of action. Actinomycetes which produce this group of compounds possess ribonucleic acid-pentose methylases, which act upon 23S ribosomal ribonucleic acid and render ribosomes resistant to the action of these antibiotics. This is achieved via the formation of a single residue of 2'-O-methyladenosine per ribosome. PMID:6155371

  10. Analysis of a ribosomal RNA operon in the actinomycete Frankia.

    PubMed

    Normand, P; Cournoyer, B; Simonet, P; Nazaret, S

    1992-02-01

    The organisation of ribosomal RNA-encoding (rrn) genes has been studied in Frankia sp. strain ORS020606. The two rrn clusters present in Frankia strain ORS020606 were isolated from genomic banks in phage lambda EMBL3 by hybridization with oligodeoxyribonucleotide probes. The 5'-3' gene order is the usual one for bacteria: 16S-23S-5S. The two clusters are not distinguishable by restriction enzyme mapping inside the coding section, but vary considerably outside it. Sequencing showed that the 16S-rRNA-encoding gene of ORS020606 is very closely related to that of another Alnus-infective Frankia strain (Ag45/Mut15) and highly homologous to corresponding genes of Streptomyces spp. Two possible promoter sequences were detected upstream from the 16S gene, while no tRNA-encoding gene was detected in the whole operon. Regions with a high proportion of divergence for the study of phylogenetic relationships within the genus were looked for and found in the first intergenic spacer, in the 23S and in the 16S gene. PMID:1372279

  11. Occupational allergic respiratory diseases in garbage workers: relevance of molds and actinomycetes.

    PubMed

    Hagemeyer, O; Bünger, J; van Kampen, V; Raulf-Heimsoth, M; Drath, C; Merget, R; Brüning, Th; Broding, H C

    2013-01-01

    Exposures to molds and bacteria (especially actinomycetes) at workplaces are common in garbage workers, but allergic respiratory diseases due to these microorganisms have been described rarely. The aim of our study was a detailed analysis of mold or bacteria-associated occupational respiratory diseases in garbage workers. From 2002 to 2011 four cases of occupational respiratory diseases related to garbage handling were identified in our institute (IPA). Hypersensitivity pneumonitis (HP) was diagnosed in three subjects (cases 1-3, one smoker, two non-smokers), occupational asthma (OA) was diagnosed in one subject (case 4, smoker), but could not be excluded completely in case 2. Cases 1 and 2 worked in composting sites, while cases 3 and 4 worked in packaging recycling plants. Exposure periods were 2-4 years. Molds and actinomycetes were identified as allergens in all cases. Specific IgE antibodies to Aspergillus fumigatus were detected exclusively in case 4. Diagnoses of HP were essentially based on symptoms and the detection of specific IgG serum antibodies to molds and actinomycetes. OA was confirmed by bronchial provocation test with Aspergillus fumigatus in case 4. In conclusion, occupational HP and OA due to molds occur rarely in garbage workers. Technical prevention measures are insufficient and the diagnosis of HP is often inconclusive. Therefore, it is recommended to implement the full repertoire of diagnostic tools including bronchoalveolar lavage and high resolution computed tomography in the baseline examination. PMID:23835992

  12. Actinomycetes: A Repertory of Green Catalysts with a Potential Revenue Resource

    PubMed Central

    Prakash, Divya; Nawani, Neelu; Prakash, Mansi; Bodas, Manish; Mandal, Abul; Khetmalas, Madhukar; Kapadnis, Balasaheb

    2013-01-01

    Biocatalysis, one of the oldest technologies, is becoming a favorable alternative to chemical processes and a vital part of green technology. It is an important revenue generating industry due to a global market projected at $7 billion in 2013 with a growth of 6.7% for enzymes alone. Some microbes are important sources of enzymes and are preferred over sources of plant and animal origin. As a result, more than 50% of the industrial enzymes are obtained from bacteria. The constant search for novel enzymes with robust characteristics has led to improvisations in the industrial processes, which is the key for profit growth. Actinomycetes constitute a significant component of the microbial population in most soils and can produce extracellular enzymes which can decompose various materials. Their enzymes are more attractive than enzymes from other sources because of their high stability and unusual substrate specificity. Actinomycetes found in extreme habitats produce novel enzymes with huge commercial potential. This review attempts to highlight the global importance of enzymes and extends to signify actinomycetes as promising harbingers of green technology. PMID:23691495

  13. Diversity of Fungi, Bacteria, and Actinomycetes on Leaves Decomposing in a Stream▿

    PubMed Central

    Das, Mitali; Royer, Todd V.; Leff, Laura G.

    2007-01-01

    Although fungi, bacteria, and specific bacterial taxa, such as the actinomycetes, have been studied extensively in various habitats, few studies have examined them simultaneously, especially on decomposing leaves in streams. In this study, sugar maple and white oak leaves were incubated in a stream in northeastern Ohio for 181 days during which samples were collected at regular intervals. Following DNA extraction, PCR-denaturing gradient gel electrophoresis (DGGE) was performed using fungus-, bacterium-, and actinomycete-specific primers. In addition, fungal and bacterial biomass was estimated. Fungal biomass differed on different days but not between leaves of the two species and was always greater than bacterial biomass. There were significant differences in bacterial biomass through time and between leaf types on some days. Generally, on the basis of DGGE, few differences in community structure were found for different leaf types. However, the ribotype richness of fungi was significantly greater than those of the bacteria and actinomycetes, which were similar to each other. Ribotype richness decreased toward the end of the study for each group except bacteria. Lack of differences between the two leaf types suggests that the microorganisms colonizing the leaf biofilm were primarily generalists that could exploit the resources of the leaves of either species equally well. Thus, we conclude that factors, such as the ecological role of the taxa (generalists versus specialists), stage of decay, and time of exposure, appeared to be more important determinants of microbial community structure than leaf quality. PMID:17142366

  14. Mesophilic Actinomycetes in the natural and reconstructed sand dune vegetation zones of Fraser Island, Australia.

    PubMed

    Kurtböke, D I; Neller, R J; Bellgard, S E

    2007-08-01

    The natural coastal habitat of Fraser Island located in the State of Queensland, Australia, has been disturbed in the past for mining of the mineral sand ilmenite. Currently, there is no information available on whether these past mining disturbances have affected the distribution, diversity, and survival of beneficial soil microorganisms in the sand dunes of the island. This in turn could deleteriously affect the success of the natural regeneration, plant growth, and establishment on the sand dunes. To support ongoing restoration efforts at sites like these mesophilic actinomycetes were isolated using conventional techniques, with particular emphasis on the taxa previously reported to produce plant-growth-promoting substances and providing support to mycorrhizal fungi, were studied at disturbed sites and compared with natural sites. In the natural sites, foredunes contained higher densities of micromonosporae replaced by increasing numbers of streptomycete species in the successional dune and finally leading to complex actinomycete communities in the mature hind dunes. Whereas in the disturbed zones affected by previous mining activities, which are currently being rehabilitated, no culturable actinomycete communities were detected. These findings suggest that the paucity of beneficial microflora in the rehabilitated sand dunes may be limiting the successful colonization by pioneer plant species. Failure to establish a cover of plant species would result in the mature hind dune plants being exposed to harsh salt and climatic conditions. This could exacerbate the incidence of wind erosion, resulting in the destabilization of well-defined and vegetated successional dunal zones. PMID:17578635

  15. Old Meets New: Using Interspecies Interactions to Detect Secondary Metabolite Production in Actinomycetes

    PubMed Central

    Clardy, Jon; Kolter, Roberto

    2014-01-01

    Actinomycetes, a group of filamentous, Gram-positive bacteria, have long been a remarkable source of useful therapeutics. Recent genome sequencing and transcriptomic studies have shown that these bacteria, responsible for half of the clinically used antibiotics, also harbor a large reservoir of gene clusters, which have the potential to produce novel secreted small molecules. Yet, many of these clusters are not expressed under common culture conditions. One reason why these clusters have not been linked to a secreted small molecule lies in the way that actinomycetes have typically been studied: as pure cultures in nutrient-rich media that do not mimic the complex environments in which these bacteria evolved. New methods based on multispecies culture conditions provide an alternative approach to investigating the products of these gene clusters. We have recently implemented binary interspecies interaction assays to mine for new secondary metabolites and to study the underlying biology in inter-actinomycete interactions. Here we describe the detailed biological and chemical methods comprising these studies. PMID:23084935

  16. Changes in the structure of the rhizosphere complex of actinomycetes in the ontogenesis of winter rye

    NASA Astrophysics Data System (ADS)

    Shirokikh, I. G.; Merzaeva, O. V.; Zenova, G. M.

    2006-06-01

    Changes in the taxonomic structure of actinomycetes in the rhizosphere of winter rye ( Secale cereale L.) growing on acid soddy-podzolic soil were studied. During the first stages of ontogenesis of winter rye, the rhizosphere complex of mycelial prokaryotes was characterized by a relatively level generic structure (with respect to the indices of abundance and frequency of particular genera), low values of the species diversity, and low domination frequency of the species from the Streptomyces genus. The numbers and species diversity of the streptomycetes increased during the further growth of the winter rye, so that streptomycetes became a dominant group in the complex of the rhizosphere actinomycetes. According to the two-way ANOVA, the population density of the Micromonospora and the Streptosporangium genera in the rhizosphere was mainly dictated by the winter rye variety, whereas the population density of the streptomycetes depended on the particular stage of the winter rye development. The differences between the actinomycetal complexes characteristic of different varieties of winter rye at the early stages of its development was leveled by the end of the winter rye growth.

  17. Conservation of thiol-oxidative stress responses regulated by SigR orthologues in actinomycetes

    PubMed Central

    Kim, Min-Sik; Dufour, Yann S.; Yoo, Ji Sun; Cho, Yoo-Bok; Park, Joo-Hong; Nam, Gi-Baeg; Kim, Hae Min; Lee, Kang-Lok; Donohue, Timothy J.; Roe, Jung-Hye

    2015-01-01

    Summary Numerous thiol-reactive compounds cause oxidative stress where cells counteract by activation of survival strategies regulated by thiol-based sensors. In Streptomyces coelicolor, a model actinomycete, a sigma/antisigma pair SigR/RsrA controls the response to thiol-oxidative stress. To unravel its full physiological functions, chromatin immuno-precipitation combined with sequence and transcript analyses were employed to identify 108 SigR target genes in S. coelicolor and to predict orthologous regulons across actinomycetes. In addition to reported genes for thiol homeostasis, protein degradation and ribosome modulation, 64 additional operons were identified suggesting new functions of this global regulator. We demonstrate that SigR maintains the level and activity of the housekeeping sigma factor HrdB during thiol-oxidative stress, a novel strategy for stress responses. We also found that SigR defends cells against UV and thiol-reactive damages, in which repair UvrA takes a part. Using a refined SigR-binding sequence model, SigR orthologues and their targets were predicted in 42 actinomycetes. This revealed a conserved core set of SigR targets to function for thiol homeostasis, protein quality control, possible modulation of transcription and translation, flavin-mediated redox reactions, and Fe-S delivery. The composition of the SigR regulon reveals a robust conserved physiological mechanism to deal with thiol-oxidative stress from bacteria to human. PMID:22651816

  18. Novel actinomycete and a cyanide-degrading pseudomonad isolated from industrial sludge

    SciTech Connect

    White, J.M.

    1987-01-01

    A novel actinomycete was the predominant filamentous microorganism in bulking activated sludge in a bench-scale reactor treating coke plant wastewater. The bacterium was isolated and identified as an actinomycete that is biochemically and morphologically similar to Amycolatopsis orientalis; however, a lack of DNA homology excludes true relatedness. At present, the isolate (NRRL B 16216) cannot be assigned to the recognized taxa of actinomycetes. Cyanide-degrading microorganisms were selected in chemostats maintained at a low dilution rate for several weeks. Cyanide alone or cyanide plus phenol were fully degraded when equilibrium was achieved, and increasing concentrations of cyanide were degraded until inhibition of cell division resulted in cell washout. An isolated non-fluorescent pseudomonad could be adapted to degrade high concentrations of cyanide and to utilize cyanide-nitrogen when phenol or lactate was the carbon source. Although one-carbon compounds such as methanol and methylamine were growth substrates, cyanide was not utilized as a carbon source. In the absence of cyanide, adaptation was gradually lost. Oxygen consumption of adapted cells was stimulated in the presence of cyanide whereas that of unadapted cells was depressed. Cyanide was degraded by growing or resting cells and by cell-free extracts. Cyanide degrading activity of cell-free extracts, lost upon dialysis, was fully restored with NAD(P)H.

  19. Draft Genome Sequence of Frankia sp. Strain BMG5.12, a Nitrogen-Fixing Actinobacterium Isolated from Tunisian Soils.

    PubMed

    Nouioui, Imen; Beauchemin, Nicholas; Cantor, Michael N; Chen, Amy; Detter, J Chris; Furnholm, Teal; Ghodhbane-Gtari, Faten; Goodwin, Lynne; Gtari, Maher; Han, Cliff; Han, James; Huntemann, Marcel; Hua, Susan Xinyu; Ivanova, Natalia; Kyrpides, Nikos; Markowitz, Victor; Mavrommatis, Kostas; Mikhailova, Natalia; Nordberg, Henrik P; Ovchinnikova, Galina; Pagani, Ioanna; Pati, Amrita; Sen, Arnab; Sur, Saubashya; Szeto, Ernest; Thakur, Subarna; Wall, Luis; Wei, Chia-Lin; Woyke, Tanja; Tisa, Louis S

    2013-01-01

    Members of the actinomycete genus Frankia form a nitrogen-fixing symbiosis with 8 different families of actinorhizal plants. We report a draft genome sequence for Frankia sp. strain BMG5.12, a nitrogen-fixing actinobacterium isolated from Tunisian soils with the ability to infect Elaeagnus angustifolia and Myrica gale. PMID:23846272

  20. Design and characterization of a single channel two-liquid capacitor and its application to hyperelastic strain sensing.

    PubMed

    Liu, Shanliangzi; Sun, Xiaoda; Hildreth, Owen J; Rykaczewski, Konrad

    2015-03-01

    Room temperature liquid-metal microfluidic devices are attractive systems for hyperelastic strain sensing. These liquid-phase electronics are intrinsically soft and retain their functionality even when stretched to several times their original length. Currently two types of liquid metal-based strain sensors exist for in-plane measurements: single-microchannel resistive and two-microchannel capacitive devices. With a winding serpentine channel geometry, these sensors typically have a footprint of about a square centimeter. This large footprint of an individual device limits the number of sensors that can be embedded into, for example, electronic fabric or skin. In this work we introduce an alternative capacitor design consisting of two liquid metal electrodes separated by a liquid dielectric material within a single straight channel. Using a liquid insulator instead of a solid elastomer enables us to tailor the system's capacitance by selecting high or low dielectric constant liquids. We quantify the effects of the electrode geometry including the diameter, spacing, and meniscus shape as well as the dielectric constant of the insulating liquid on the overall system's capacitance. We also develop a procedure for fabricating the two-liquid capacitor within a single straight polydiemethylsiloxane channel and demonstrate that this device can have about 25 times higher capacitance per sensor's base area when compared to two-channel liquid metal capacitors. Lastly, we characterize the response of this compact device to strain and identify operational issues arising from complex hydrodynamics near liquid-liquid and liquid-elastomer interfaces. PMID:25592044

  1. Anticancer property of sediment actinomycetes against MCF-7 and MDA-MB-231 cell lines

    PubMed Central

    Ravikumar, S; Fredimoses, M; Gnanadesigan, M

    2012-01-01

    Objective To investigate the anticancer property of marine sediment actinomycetes against two different breast cancer cell lines. Methods In vitro anticancer activity was carried out against breast (MCF-7 and MDA-MB-231) cancer cell lines. Partial sequences of the 16s rRNA gene, phylogenetic tree construction, multiple sequence analysis and secondary structure analysis were also carried out with the actinomycetes isolates. Results Of the selected five actinomycete isolates, ACT01 and ACT02 showed the IC50 value with (10.13±0.92) and (22.34±5.82) µg/mL concentrations, respectively for MCF-7 cell line at 48 h, but ACT01 showed the minimum (18.54±2.49 µg/mL) level of IC50 value with MDA-MB-231 cell line. Further, the 16s rRNA partial sequences of ACT01, ACT02, ACT03, ACT04 and ACT05 isolates were also deposited in NCBI data bank with the accession numbers of GQ478246, GQ478247, GQ478248, GQ478249 and GQ478250, respectively. The phylogenetic tree analysis showed that, the isolates of ACT02 and ACT03 were represented in group I and III, respectively, but ACT01 and ACT02 were represented in group II. The multiple sequence alignment of the actinomycete isolates showed that, the maximum identical conserved regions were identified with the nucleotide regions of 125 to 221st base pairs, 65 to 119th base pairs and 55, 48 and 31st base pairs. Secondary structure prediction of the 16s rRNA showed that, the maximum free energy was consumed with ACT03 isolate (-45.4 kkal/mol) and the minimum free energy was consumed with ACT04 isolate (-57.6 kkal/mol). Conclusions The actinomycete isolates of ACT01 and ACT02 (GQ478246 and GQ478247) which are isolated from sediment sample can be further used as anticancer agents against breast cancer cell lines. PMID:23569875

  2. Impact of linker strain and flexibility in the design of a fragment-based inhibitor

    PubMed Central

    Chung, Suhman; Parker, Jared B.; Bianchet, Mario; Amzel, L. Mario; Stivers, James T.

    2011-01-01

    The linking together of molecular fragments that bind to adjacent sites on an enzyme can lead to high affinity inhibitors. Ideally, this strategy would employ linkers that do not perturb the optimal binding geometries of the fragments and do not have excessive conformational flexibility that would increase the entropic penalty of binding. In reality, these aims are seldom realized due to limitations in linker chemistry. Here we systematically explore the energetic and structural effects of rigid and flexible linkers on the binding of a fragment-based inhibitor of human uracil DNA glycosylase. Analysis of the free energies of binding in combination with co-crystal structures shows that the flexibility and strain of a given linker can have a significant impact on binding affinity even when the binding fragments are optimally positioned. Such effects are not apparent from inspection of structures and underscore the importance of linker optimization in fragment-based drug discovery efforts. PMID:19396178

  3. Comparative finite element analysis of the stress-strain states in three different bonded solid oxide fuel cell seal designs

    NASA Astrophysics Data System (ADS)

    Weil, K. S.; Koeppel, B. J.

    One of the critical issues in designing and fabricating a high performance planar solid oxide fuel cell (pSOFC) stack is the development of the appropriate materials and techniques for hermetically sealing the metal and ceramic components. A second critical issue is ensuring that the brittle ceramic cell constituents, i.e. the electrodes and electrolyte, exhibit high mechanical reliability by mitigating potential sources of thermal-mechanically induced stresses that can lead to fracture during operation and/or shutdown. A foil-based sealing approach is currently being developed that appears to offer good hermeticity and mechanical integrity, while minimizing the generation of high stresses in either of the joint's substrate materials. Based on the concept's viability, demonstrated in prior experimental work, numerical analyses were conducted to evaluate the behavior and benefits of the seal in a configuration prototypic of current pSOFC stack designs. This paper presents recent results from finite element (FE) simulations of a planar cell using the foil-based seal, along with companion analyses of the more conventionally employed glass-ceramic and brazed joints. The stresses and deformations of the components were evaluated at isothermal operating and shutdown temperatures. The results indicate that the foil seal is able to accommodate a significant degree of thermal mismatch strain between the metallic support structure and the ceramic cell via elastic deformations of the foil and plasticity in the foil-to-cell braze layer. Consequently the cell stresses in this type of seal are predicted to be much lower than those in the glass-ceramic and brazed designs, which is expected to lead to improved stack reliability. This ability to accommodate large thermal strain mismatches allows the design requirement of thermal expansion matching between ceramic and metal stack components to be relaxed and expands the list of candidate materials that can be considered for the

  4. The biodegradation of layered silicates under the influence of cyanobacterial-actinomycetes associations

    NASA Astrophysics Data System (ADS)

    Ivanova, Ekaterina

    2013-04-01

    The weathering of sheet silicates is well known to be related to local and global geochemical cycles. Content and composition of clay minerals in soil determine the sorption properties of the soil horizons, water-holding capacity of the soil, stickiness, plasticity, etc. Microorganisms have a diverse range of mechanisms of minerals' structure transformation (acid- and alkali formation, biosorption, complexing, etc). One of the methods is an ability of exopolysaccharide-formation, in particular the formation of mucus, common to many bacteria, including cyanobacteria. Mucous covers cyanobacteria are the specific econiches for other bacteria, including actinomycetes. The objective was to analyze the structural changes of clay minerals under the influence of the cyanobacterial-actinomycetes associative growth. The objects of the study were: 1) the experimental symbiotic association, consisting of free-living heterocyst-formative cyanobacterium Anabaena variabilis Kutz. ATCC 294132 and actinomycete Streptomyces cyaneofuscatus FR837630, 2) rock samples obtained from the Museum of the Soil Science Department of the Lomonosov Moscow State University: kaolinite, consisting of kaolin (96%) Al4 (OH) 8 [Si4O10]; mixed with hydromica, chlorite and quartz; vermiculite, consisting of vermiculite (Ca, Mg, ...)*(Mg, Fe)3(OH)2[(Si, Al)4O10]*4H2O and trioctahedral mica (biotite). The mineralogical compositions of the rocks were determined by the universal X-ray Diffractometer Carl Zeiss Yena. The operationg regime was kept constant (30 kv, 40 mA). The cultivation of the association of actinomycete S. cyanoefuscatus and cyanobacterium A. variabilis caused a reduction in the intensity of kaolinite and hydromica reflexes. However, since both (mica and kaolinite) components have a rigid structure, the significant structural transformation of the minerals was not revealed. Another pattern was observed in the experiment, where the rock sample of vermiculite was used as the mineral

  5. Quantification of Gordona amarae Strains in Foaming Activated Sludge and Anaerobic Digester Systems with Oligonucleotide Hybridization Probes

    PubMed Central

    de los Reyes, M. Fiorella; de los Reyes, Francis L.; Hernandez, Mark; Raskin, Lutgarde

    1998-01-01

    Previous studies have shown the predominance of mycolic acid-containing filamentous actinomycetes (mycolata) in foam layers in activated sludge systems. Gordona (formerly Nocardia) amarae often is considered the major representative of this group in activated sludge foam. In this study, small-subunit rRNA genes of four G. amarae strains were sequenced, and the resulting sequences were compared to the sequence of G. amarae type strain SE-6. Comparative sequence analysis showed that the five strains used represent two lines of evolutionary descent; group 1 consists of strains NM23 and ASAC1, and group 2 contains strains SE-6, SE-102, and ASF3. The following three oligonucleotide probes were designed: a species-specific probe for G. amarae, a probe specific for group 1, and a probe targeting group 2. The probes were characterized by dissociation temperature and specificity studies, and the species-specific probe was evaluated for use in fluorescent in situ hybridizations. By using the group-specific probes, it was possible to place additional G. amarae isolates in their respective groups. The probes were used along with previously designed probes in membrane hybridizations to determine the abundance of G. amarae, group 1, group 2, bacterial, mycolata, and Gordona rRNAs in samples obtained from foaming activated sludge systems in California, Illinois, and Wisconsin. The target groups were present in significantly greater concentrations in activated sludge foam than in mixed liquor and persisted in anaerobic digesters. Hybridization results indicated that the presence of certain G. amarae strains may be regional or treatment plant specific and that previously uncharacterized G. amarae strains may be present in some systems. PMID:9647822

  6. Quantification of Gordona amarae strains in foaming activated sludge and anaerobic digester systems with oligonucleotide hybridization probes.

    PubMed

    de los Reyes, M F; de los Reyes, F L; Hernandez, M; Raskin, L

    1998-07-01

    Previous studies have shown the predominance of mycolic acid-containing filamentous actinomycetes (mycolata) in foam layers in activated sludge systems. Gordona (formerly Nocardia) amarae often is considered the major representative of this group in activated sludge foam. In this study, small-subunit rRNA genes of four G. amarae strains were sequenced, and the resulting sequences were compared to the sequence of G. amarae type strain SE-6. Comparative sequence analysis showed that the five strains used represent two lines of evolutionary descent; group 1 consists of strains NM23 and ASAC1, and group 2 contains strains SE-6, SE-102, and ASF3. The following three oligonucleotide probes were designed: a species-specific probe for G. amarae, a probe specific for group 1, and a probe targeting group 2. The probes were characterized by dissociation temperature and specificity studies, and the species-specific probe was evaluated for use in fluorescent in situ hybridizations. By using the group-specific probes, it was possible to place additional G. amarae isolates in their respective groups. The probes were used along with previously designed probes in membrane hybridizations to determine the abundance of G. amarae, group 1, group 2, bacterial, mycolata, and Gordona rRNAs in samples obtained from foaming activated sludge systems in California, Illinois, and Wisconsin. The target groups were present in significantly greater concentrations in activated sludge foam than in mixed liquor and persisted in anaerobic digesters. Hybridization results indicated that the presence of certain G. amarae strains may be regional or treatment plant specific and that previously uncharacterized G. amarae strains may be present in some systems. PMID:9647822

  7. Bioactive 2(1H)-Pyrazinones and Diketopiperazine Alkaloids from a Tunicate-Derived Actinomycete Streptomyces sp.

    PubMed

    Shaala, Lamiaa A; Youssef, Diaa T A; Badr, Jihan M; Harakeh, Steve M

    2016-01-01

    As a part of our ongoing effort to allocate marine microbial bioactive leads, a tunicate-derived actinomycete, Streptomyces sp. Did-27, was investigated. Three new 2(1H)-pyrazinones derivatives, (S)-6-(sec-butyl)-3-isopropylpyrazin-2(1H)-one (1), (S)-3-(sec-butyl)-6-isopropylpyrazin-2(1H)-one (2) and (S)-6-(sec-butyl)-3-isobutylpyrazin-2(1H)-one (3), together with the known (1H)-pyrazinones analogues deoxymutaaspergillic acid (4), 3,6-diisobutyl-2(1H)-pyrazinone (5) and 3,6-di-sec-butyl-2(1H)-pyrazinone (6), and the diketopiperazine alkaloids cyclo(6-OH-d-Pro-l-Phe) (7), bacillusamide B (8), cyclo(l-Pro-l-Leu) and cyclo(l-Pro-l-Ile) (10) were isolated from this strain. The structures of the compounds were determined by study of their one- and two-dimensional NMR spectra as well as high-resolution mass spectral determinations. Compound 4 was reported previously as a synthetic product, while compound 6 was reported as 2-hydroxy-3,6-di-sec-butylpyrazine. Herein, we report the complete NMR data for compounds 4 and 6. The compounds were evaluated for their cytotoxic activities against three cell lines. Compound 5 showed potent and selective activity against HCT-116 cell line with IC50 of 1.5 μg/mL, while 1-10 showed variable cytotoxic activities against these cancer cell lines. These results provide further understanding about the chemistry and bioactivities of the alkylated 2(1H)-pyrazinone derivatives. PMID:27563872

  8. Streptomyces xinjiangensis sp. nov., an actinomycete isolated from Lop Nur region.

    PubMed

    Cheng, Cong; Li, Yu-Qian; Asem, Mipeshwaree Devi; Lu, Chun-Yan; Shi, Xiao-Han; Chu, Xiao; Zhang, Wan-Qin; Di An, Deng-; Li, Wen-Jun

    2016-10-01

    A novel actinobacterial strain, designated LPA192(T), was isolated from a soil sample collected from Lop Nur, Xinjiang Uygur Autonomous Region, Northwest China. A polyphasic approach was used to investigate the taxonomic position of strain LPA192(T). The isolate showed morphological and chemotaxonomic characteristics typical of members of the genus Streptomyces. Peptidoglycan was found to contain LL-diaminopimelic acid as the diagnostic diamino acid. The predominant menaquinones were MK-9(H6) and MK-10(H4). Polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylinositol. Major cellular fatty acids consist of C16:0, anteiso-C15:0 and C18:1 ω9c. The sugar in whole-cell hydrolysates was mannose. Phylogenetic analysis indicated that strain LPA192(T) is closely related to Streptomyces tanashiensis LMG 20274(T) (99.3 %), Streptomyces gulbargensis DAS131(T) (99.3 %), Streptomyces nashvillensis NBRC 13064(T) (99.3 %), Streptomyces roseolus NBRC 12816(T) (99.2 %) and Streptomyces filamentosus NBRC 12767(T) (99.1 %) while showing below 98.5 % sequencing similarities with other validly published Streptomyces species. However, DNA-DNA relatedness values between LPA192(T) and the closely related type strains were below 40 %, which are much lower than 70 % threshold value for species delineation. The genomic DNA G + C content of strain LPA192(T) was 69.3 mol %. Based on the differences in genotypic and phenotypic characteristics from the closely related strains, strain LPA192(T) is considered to represent a novel species of the genus Streptomyces for which the name Streptomyces xinjiangensis sp. nov. is proposed. The type strain is LPA192(T) (=KCTC 39601(T) = CGMCC 4.7288(T)). PMID:27209413

  9. Evaluating a prototype device designed to alleviate night vision goggle induced neck strain among military personnel.

    PubMed

    Dibblee, Jenna; Worthy, Portia; Farrell, Philip; Hetzler, Markus; Reid, Susan; Stevenson, Joan; Fischer, Steven

    2015-01-01

    The purpose of this study was verify the design of a novel Helmet System Support Device (HSSD) that can be used by military aircrew to help intervene on and reduce the high prevalence of neck trouble. Twelve healthy participants repeated simulated helicopter aircrew tasks on 3 separate days. On each day they wore a different helmet configuration, where measures of performance, perceived demand/preference and muscular demand were recorded. The results showed that vigilance tasks were performed over 10% faster with the HSSD configuration compared to wearing the normal helmet configuration. Participants were able to maintain static (endurance) postures for 28% longer, and use of the HSSD helped to prevent neck muscle fatigue in the most demanding task. The results of this design verification study indicate that the HSSD may be a realistic, feasible near-term solution to intervene on the high prevalence of neck trouble among rotary-wing aircrew. Practitioner Summary: This paper verifies the effectiveness of the Helmet System Support Device (HSSD) as an on-body personal protective device to help control exposures associated with aircrew neck trouble. The HSSD reduced perceived demand, reduced cumulative muscle activity in select muscles and provided improved fatigue resistance, meeting its desired design objectives. PMID:25932658

  10. Design and application of two oligonucleotide probes for the identification of Geodermatophilaceae strains using fluorescence in situ hybridization (FISH).

    PubMed

    Urzì, Clara; La Cono, Violetta; Stackebrandt, Erko

    2004-07-01

    Bacteria of the family of Geodermatophilaceae are actively involved in the decay processes [Urzì, C. and Realini, M. (1998) Int Biodeterior Biodegrad 42: 45-54; Urzì, C., Salamone, P., Schumann, P., and Stackebrandt, E. (2000) Int J Syst Evol Microbiol 50: 529-536] of stone monuments. Characterization of isolates includes phenotypic, chemotaxonomic and genetic analysis often requiring long-term procedures. The use of specific probes for members of Geodermatophilaceae family could be useful for the easy detection of those strains colonizing rock surfaces and involved in the biodeterioration. Two 16S rRNA-targeted oligonucleotide probes were designed for the specific detection of members of the family Geodermatophilaceae using fluorescence in situ hybridization (FISH); one probe specific for members of the two genera Geodermatophilus/Blastococcus and the second for members of the genus Modestobacter. PMID:15186346

  11. Detection of multiple strains of rabies virus RNA using primers designed to target Mexican vampire bat variants.

    PubMed

    Loza-Rubio, E; Rojas-Anaya, E; Banda-Ruíz, V M; Nadin-Davis, S A; Cortez-García, B

    2005-10-01

    A reverse transcription-polymerase chain reaction (RT-PCR), that uses primers specifically designed to amplify a portion of the N gene of vampire bat strains of rabies that circulate in Mexico, but also recognizing most of the rabies variants circulating in endemic areas, was established. This standardized PCR assay was able to detect viral RNA in tenfold serial dilutions up to a 10(7) dilution using stock virus at an original titre of 10(7.5) LD50. The assay was highly specific for rabies virus. Forty different rabies isolates recovered from different species and geographical regions in the country were diagnosed as positive and negative by the fluorescent antibody test (FAT). These same samples were re-examined by both PCR and the mouse inoculation test (MIT). Compared with MIT the PCR exhibited an epidemiological sensitivity of 86% and a specificity of 91% while its positive predictive value was 96%. PMID:16181515

  12. Detection of multiple strains of rabies virus RNA using primers designed to target Mexican vampire bat variants.

    PubMed Central

    Loza-Rubio, E.; Rojas-Anaya, E.; Banda-Ruíz, V. M.; Nadin-Davis, S. A.; Cortez-García, B.

    2005-01-01

    A reverse transcription-polymerase chain reaction (RT-PCR), that uses primers specifically designed to amplify a portion of the N gene of vampire bat strains of rabies that circulate in Mexico, but also recognizing most of the rabies variants circulating in endemic areas, was established. This standardized PCR assay was able to detect viral RNA in tenfold serial dilutions up to a 10(7) dilution using stock virus at an original titre of 10(7.5) LD50. The assay was highly specific for rabies virus. Forty different rabies isolates recovered from different species and geographical regions in the country were diagnosed as positive and negative by the fluorescent antibody test (FAT). These same samples were re-examined by both PCR and the mouse inoculation test (MIT). Compared with MIT the PCR exhibited an epidemiological sensitivity of 86% and a specificity of 91% while its positive predictive value was 96%. PMID:16181515

  13. Novel benzofuroxan derivatives against multidrug-resistant Staphylococcus aureus strains: design using Topliss' decision tree, synthesis and biological assay.

    PubMed

    Jorge, Salomão Dória; Palace-Berl, Fanny; Masunari, Andrea; Cechinel, Cléber André; Ishii, Marina; Pasqualoto, Kerly Fernanda Mesquita; Tavares, Leoberto Costa

    2011-08-15

    The aim of this study was the design of a set of benzofuroxan derivatives as antimicrobial agents exploring the physicochemical properties of the related substituents. Topliss' decision tree approach was applied to select the substituent groups. Hierarchical cluster analysis was also performed to emphasize natural clusters and patterns. The compounds were obtained using two synthetic approaches for reducing the synthetic steps as well as improving the yield. The minimal inhibitory concentration method was employed to evaluate the activity against multidrug-resistant Staphylococcus aureus strains. The most active compound was 4-nitro-3-(trifluoromethyl)[N'-(benzofuroxan-5-yl)methylene]benzhydrazide (MIC range 12.7-11.4 μg/mL), pointing out that the antimicrobial activity was indeed influenced by the hydrophobic and electron-withdrawing property of the substituent groups 3-CF(3) and 4-NO(2), respectively. PMID:21757359

  14. Design considerations of biaxially tensile-strained germanium-on-silicon lasers

    NASA Astrophysics Data System (ADS)

    Li, Xiyue; Li, Zhiqiang; Li, Simon; Chrostowski, Lukas; (Maggie Xia, Guangrui

    2016-06-01

    Physical models of Ge energy band structure and material loss were implemented in LASTIPTM, a 2D simulation tool for edge emitting laser diodes. This model is able to match available experimental data. Important design parameters of a Fabry–Perot Ge laser, such as the cavity length, thickness, width, polycrystalline Si cladding layer thickness were studied and optimized. The laser structure optimizations alone were shown to reduce I th by 22-fold and increase η d and η i by 11 and 6 times. The simulations also showed that improving the defect limited carrier lifetime is critical for achieving an efficient and low-threshold Ge laser. With the optimized structure design (300 μm for the cavity length, 0.4 μm for the cavity width, 0.3 μm for the cavity thickness, and 0.6 μm for the polycrystalline Si cladding layer thickness) and a defect limited carrier lifetime of 100 ns, a wall-plug efficiency of 14.6% at 1 mW output is predicted, where J th of 2.8 kA cm‑2, I th of 3.3 mA, I 1mW of 9 mA, and η d of 23.6% can be achieved. These are tremendous improvements from the available experimental values at 280 kA cm‑2, 756 mA, 837 mA and 1.9%, respectively.

  15. Screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes.

    PubMed

    Kumar, Vijay; Bharti, Alpana; Negi, Yogesh Kumar; Gusain, Omprakash; Pandey, Piyush; Bisht, Gajraj Singh

    2012-01-01

    Actinomycetes from earthworm castings were isolated and screened for their antimicrobial activity and industrial enzymes. A total of 48 isolates were obtained from 12 samples of earthworm castings. Highest numbers of isolates were recovered from forest site (58.33 %) as compared to grassland (25%) and agricultural land (16.66%). The growth patterns, mycelial coloration of abundance actinomycetes were documented. The dominant genera Identified by cultural, morphological and physiological characteristics were Streptomyces (60.41%) followed by Streptosporangium (10.41%),Saccharopolyspora (6.25%) and Nocardia (6.25%). Besides these, other genera like Micromonospora, Actinomadura, Microbispora, Planobispora and Nocardiopsis were also recovered but in low frequency. Among the 48 isolates, 52.08% were found active against one or more test organisms. Out of 25 active isolates 16% showed activity against bacterial, human fungal as well as phytopathogens. Among 48 isolates 38, 32, 21, 20, 16 and 14 produced enzyme amylase, caseinase, cellulase, gelatinase, xylanase and lipase respectively while 10 isolates produced all the enzymes. More interestingly 2, 3, and 1 isolates produced amylase, xylanase and lipase at 45°C respectively. In the view of its antimicrobial activity as well as enzyme production capability the genus Streptomyces was dominant. The isolate EWC 7(2) was most promising on the basis of its interesting antimicrobial activity and was identified as Streptomyces rochei. The results of these findings have increased the scope of finding industrially important actinomycetes from earthworm castings and these organisms could be promising sources for industrially important molecules or enzymes. PMID:24031819

  16. Screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes

    PubMed Central

    Kumar, Vijay; Bharti, Alpana; Negi, Yogesh Kumar; Gusain, Omprakash; Pandey, Piyush; Bisht, Gajraj Singh

    2012-01-01

    Actinomycetes from earthworm castings were isolated and screened for their antimicrobial activity and industrial enzymes. A total of 48 isolates were obtained from 12 samples of earthworm castings. Highest numbers of isolates were recovered from forest site (58.33 %) as compared to grassland (25%) and agricultural land (16.66%). The growth patterns, mycelial coloration of abundance actinomycetes were documented. The dominant genera Identified by cultural, morphological and physiological characteristics were Streptomyces (60.41%) followed by Streptosporangium (10.41%),Saccharopolyspora (6.25%) and Nocardia (6.25%). Besides these, other genera like Micromonospora, Actinomadura, Microbispora, Planobispora and Nocardiopsis were also recovered but in low frequency. Among the 48 isolates, 52.08% were found active against one or more test organisms. Out of 25 active isolates 16% showed activity against bacterial, human fungal as well as phytopathogens. Among 48 isolates 38, 32, 21, 20, 16 and 14 produced enzyme amylase, caseinase, cellulase, gelatinase, xylanase and lipase respectively while 10 isolates produced all the enzymes. More interestingly 2, 3, and 1 isolates produced amylase, xylanase and lipase at 45°C respectively. In the view of its antimicrobial activity as well as enzyme production capability the genus Streptomyces was dominant. The isolate EWC 7(2) was most promising on the basis of its interesting antimicrobial activity and was identified as Streptomyces rochei. The results of these findings have increased the scope of finding industrially important actinomycetes from earthworm castings and these organisms could be promising sources for industrially important molecules or enzymes. PMID:24031819

  17. The gastric caeca of pentatomids as a house for actinomycetes

    PubMed Central

    2012-01-01

    Background Microbes are extensively associated with insects, playing key roles in insect defense, nutrition and reproduction. Most of the associations reported involve Proteobacteria. Despite the fact that Actinobacteria associated with insects were shown to produce antibiotic barriers against pathogens to the hosts or to their food and nutrients, there are few studies focusing on their association with insects. Thus, we surveyed the Actinobacteria diversity on a specific region of the midgut of seven species of stinkbugs (Hemiptera: Pentatomidae) known to carry a diversity of symbiotically-associated Proteobacteria. Results A total of 34 phylotypes were placed in 11 different Actinobacteria families. Dichelops melacanthus held the highest diversity with six actinobacteria families represented by nine phylotypes. Thyanta perditor (n = 7), Edessa meditabunda (n = 5), Loxa deducta (n = 4) and Pellaea stictica (n = 3) were all associated with three families. Piezodorus guildini (n = 3) and Nezara viridula (n = 3) had the lowest diversity, being associated with two (Propionibacteriaceae and Mycobacteriaceae) and one (Streptomyceataceae) families, respectively. Corynebacteriaceae and Mycobacteriaceae were the most common families with phylotypes from three different insect species each one. Conclusions Many phylotypes shared a low 16S rRNA gene similarity with their closest type strains and formed new phyletic lines on the periphery of several genera. This is a strong indicative that stinkbug caeca can harbor new species of actinobacteria, which might be derived from specific associations with the species of stinkbugs studied. Although the well-known role of actinobacteria as a source of biomolecules, the ecological features of these symbionts on the stinkbugs biology remain unknown. PMID:22682021

  18. Acetylcholinesterase inhibitory dimeric indole derivatives from the marine actinomycetes Rubrobacter radiotolerans.

    PubMed

    Li, Jian Lin; Huang, Lei; Liu, Juan; Song, Yan; Gao, Jie; Jung, Jee H; Liu, Yonghong; Chen, Guangtong

    2015-04-01

    Investigation of the bioactive secondary metabolites of the marine actinomycetes Rubrobacter radiotolerans led to the isolation and characterization of two naturally rare dimeric indole derivatives (1 and 2). The structures of these new compounds were elucidated by spectroscopic data interpretation, and the absolute configurations were assigned by CD calculations. The acetylcholinesterase (AchE) inhibitory activity of compounds 1 and 2 was evaluated, both of which showed moderate activity with IC50 values of 11.8 and 13.5μM, respectively. PMID:25655350

  19. Juniperolide A: a new polyketide isolated from a terrestrial actinomycete, Streptomyces sp.

    PubMed

    Raju, Ritesh; Gromyko, Oleksandr; Fedorenko, Viktor; Luzhetskyy, Andriy; Plaza, Alberto; Müller, Rolf

    2012-12-01

    A new linear polyketide, juniperolide A (1), was produced by the terrestrial actinomycete (Lv1-48) isolated from the rhizosphere of the plant Juniperus excelsa. The juniperolide A (1) structure contains a THP unit and a 3-amino-2,3,6-trideoxyhexose as the glycosidic moiety. Mosher's analysis was used for absolute stereochemistry determinations at C-2, C-8, C-20, and C-4', while the relative stereochemistry assignments of the remaining stereocenters were based on ROESY correlations and J-based coupling. PMID:23170775

  20. The Marine Actinomycete Genus Salinispora: A Model Organism for Secondary Metabolite Discovery

    PubMed Central

    Jensen, Paul R.; Moore, Bradley S.; Fenical, William

    2015-01-01

    This review covers the initial discovery of the marine actinomycete genus Salinispora through its development as a model for natural product research. A focus is placed on the novel chemical structures reported with reference to their biological activities and the synthetic and biosynthetic studies they have inspired. The time line of discoveries progresses from more traditional bioassay-guided approaches through the application of genome mining and genetic engineering techniques that target the products of specific biosynthetic gene clusters. This overview exemplifies the extraordinary biosynthetic diversity that can emanate from a narrowly defined genus and supports future efforts to explore marine taxa in the search for novel natural products. PMID:25730728

  1. Biocontrol of Rhizoctonia solani damping-off and promotion of tomato plant growth by endophytic actinomycetes isolated from native plants of Algerian Sahara.

    PubMed

    Goudjal, Yacine; Toumatia, Omrane; Yekkour, Amine; Sabaou, Nasserdine; Mathieu, Florence; Zitouni, Abdelghani

    2014-01-20

    Thirty-four endophytic actinomycetes were isolated from the roots of native plants of the Algerian Sahara. Morphological and chemical studies showed that twenty-nine isolates belonged to the Streptomyces genus and five were non-Streptomyces. All isolates were screened for their in vitro antifungal activity against Rhizoctonia solani. The six that had the greatest pathogen inhibitory capacities were subsequently tested for their in vivo biocontrol potential on R. solani damping-off in sterilized and non-sterilized soils, and for their plant-growth promoting activities on tomato seedlings. In both soils, coating tomato seeds with antagonistic isolates significantly reduced (P<0.05) the severity of damping-off of tomato seedlings. Among the isolates tested, the strains CA-2 and AA-2 exhibited the same disease incidence reduction as thioperoxydicarbonic diamide, tetramethylthiram (TMTD) and no significant differences (P<0.05) were observed. Furthermore, they resulted in a significant increase in the seedling fresh weight, the seedling length and the root length of the seed-treated seedlings compared to the control. The taxonomic position based on 16S rDNA sequence analysis and phylogenetic studies indicated that the strains CA-2 and AA-2 were related to Streptomyces mutabilis NBRC 12800(T) (100% of similarity) and Streptomyces cyaneofuscatus JCM 4364(T) (100% of similarity), respectively. PMID:23920229

  2. Draft Genome Sequence of Frankia sp. Strain CcI6, a Salt-Tolerant Nitrogen-Fixing Actinobacterium Isolated from the Root Nodule of Casuarina cunninghamiana

    PubMed Central

    Mansour, Samira R.; Oshone, Rediet; Hurst, Sheldon G.; Morris, Krystalynne; Thomas, W. Kelley

    2014-01-01

    Members of the actinomycete genus Frankia form a nitrogen-fixing symbiosis with 8 different families of actinorhizal plants. We report a 5.57-Mbp draft genome sequence for Frankia sp. strain CcI6, a salt-tolerant nitrogen-fixing actinobacterium isolated from root nodules of Casurina cunninghamiana grown in Egyptian soils. PMID:24435877

  3. Draft genome sequence of Frankia sp. strain QA3, a nitrogen-fixing actinobacterium isolated from the root nodule of Alnus nitida.

    PubMed

    Sen, Arnab; Beauchemin, Nicholas; Bruce, David; Chain, Patrick; Chen, Amy; Walston Davenport, Karen; Deshpande, Shweta; Detter, Chris; Furnholm, Teal; Ghodbhane-Gtari, Faten; Goodwin, Lynne; Gtari, Maher; Han, Cliff; Han, James; Huntemann, Marcel; Ivanova, Natalia; Kyrpides, Nikos; Land, Miriam L; Markowitz, Victor; Mavrommatis, Kostas; Nolan, Matt; Nouioui, Imen; Pagani, Ioanna; Pati, Amrita; Pitluck, Sam; Santos, Catarina L; Sur, Saubashya; Szeto, Ernest; Tavares, Fernando; Teshima, Hazuki; Thakur, Subarna; Wall, Luis; Woyke, Tanja; Wishart, Jessie; Tisa, Louis S

    2013-01-01

    Members of the actinomycete genus Frankia form a nitrogen-fixing symbiosis with 8 different families of actinorhizal plants. We report a high-quality draft genome sequence for Frankia sp. strain QA3, a nitrogen-fixing actinobacterium isolated from root nodules of Alnus nitida. PMID:23516220

  4. Draft Genome Sequence of Frankia sp. Strain CcI6, a Salt-Tolerant Nitrogen-Fixing Actinobacterium Isolated from the Root Nodule of Casuarina cunninghamiana.

    PubMed

    Mansour, Samira R; Oshone, Rediet; Hurst, Sheldon G; Morris, Krystalynne; Thomas, W Kelley; Tisa, Louis S

    2014-01-01

    Members of the actinomycete genus Frankia form a nitrogen-fixing symbiosis with 8 different families of actinorhizal plants. We report a 5.57-Mbp draft genome sequence for Frankia sp. strain CcI6, a salt-tolerant nitrogen-fixing actinobacterium isolated from root nodules of Casurina cunninghamiana grown in Egyptian soils. PMID:24435877

  5. Natural and engineered biosynthesis of nucleoside antibiotics in Actinomycetes.

    PubMed

    Chen, Wenqing; Qi, Jianzhao; Wu, Pan; Wan, Dan; Liu, Jin; Feng, Xuan; Deng, Zixin

    2016-03-01

    Nucleoside antibiotics constitute an important family of microbial natural products bearing diverse bioactivities and unusual structural features. Their biosynthetic logics are unique with involvement of complex multi-enzymatic reactions leading to the intricate molecules from simple building blocks. Understanding how nature builds this family of antibiotics in post-genomic era sets the stage for rational enhancement of their production, and also paves the way for targeted persuasion of the cell factories to make artificial designer nucleoside drugs and leads via synthetic biology approaches. In this review, we discuss the recent progress and perspectives on the natural and engineered biosynthesis of nucleoside antibiotics. PMID:26153500

  6. Isolation, culture, and behavior of Frankia strain HFPCgI4 from root nodules of Casuarina glauca

    SciTech Connect

    Mansour, S.R.; Dewedar, A.; Torrey, J.G. )

    1990-12-01

    Casuarina glauca (Casuarinaceae) is an important introduced tree species in Egypt, valued for windbreaks, land stabilization, and soil improvement associated with actinomycete-induced root nodules that fix atmospheric nitrogen. A strain of Frankia designated HFPCgI4 was isolated from root nodules collected in Egypt and its characteristics assessed both in pure culture and in symbiosis. Strain CgI4 grows well in synthetic nutrient medium with added NH{sub 4}{sup +} or, in the absence of combined N in the medium, forms vesicles and fixes dinitrogen adequate for growth. Hyphae, vesicles, sporangia, and spores characteristic of the genus Frankia were observed. This strain shows spontaneous spore release when grown in media lacking N. When tested for infectivity on actinorhizal host plants grown in unaerated water culture, CgI4 nodulates several species of Casuarina that fix atmospheric dinitrogen. Other genera in the Casuarinaceae, namely, Allocasuarina and Gymnostoma, were not nodulated under these conditions. Species of the genus Myrica and Comptonia peregrina (Myricaceae) were effectively nodulated by CgI4. The isolate may have use as an inoculant for forest plantations using species of Casuarina sensu stricta.

  7. Application of statistical experimental design for optimisation of bioinsecticides production by sporeless Bacillus thuringiensis strain on cheap medium

    PubMed Central

    Ben Khedher, Saoussen; Jaoua, Samir; Zouari, Nabil

    2013-01-01

    In order to overproduce bioinsecticides production by a sporeless Bacillus thuringiensis strain, an optimal composition of a cheap medium was defined using a response surface methodology. In a first step, a Plackett-Burman design used to evaluate the effects of eight medium components on delta-endotoxin production showed that starch, soya bean and sodium chloride exhibited significant effects on bioinsecticides production. In a second step, these parameters were selected for further optimisation by central composite design. The obtained results revealed that the optimum culture medium for delta-endotoxin production consists of 30 g L−1 starch, 30 g L−1 soya bean and 9 g L−1 sodium chloride. When compared to the basal production medium, an improvement in delta-endotoxin production up to 50% was noted. Moreover, relative toxin yield of sporeless Bacillus thuringiensis S22 was improved markedly by using optimised cheap medium (148.5 mg delta-endotoxins per g starch) when compared to the yield obtained in the basal medium (94.46 mg delta-endotoxins per g starch). Therefore, the use of optimised culture cheap medium appeared to be a good alternative for a low cost production of sporeless Bacillus thuringiensis bioinsecticides at industrial scale which is of great importance in practical point of view. PMID:24516462

  8. Siderophore production by actinomycetes isolates from two soil sites in Western Australia.

    PubMed

    Lee, Joanna; Postmaster, Armin; Soon, Hooi Peng; Keast, David; Carson, Kerry C

    2012-04-01

    The actinomycetes are metabolically flexible soil micro-organisms capable of producing a range of compounds of interest, including siderophores. Siderophore production by actinomycetes sampled from two distinct and separate geographical sites in Western Australia were investigated and found to be generally similar in the total percentage of siderophore producers found. The only notable difference was the proportion of isolates producing catechol siderophores with only 3% found in site 1 (from the north-west of Western Australia and reportedly containing 40% magnetite) and 17% in site 2 (a commercial stone fruit orchard in the hills east of Perth with a soil base ranging from sandy loam to laterite). Further detailed characterization of isolates of interest identified a Streptomyces that produced extracellularly excreted enterobactin, the characteristic Enterobacteriaceae siderophore, and also revealed some of the conditions required for enterobactin production. Carriage of the entF gene, which codes for the synthetase responsible for the final assembly of the tri-cyclic structure of enterobactin, was confirmed by PCR in this isolate. Another separate Streptomyces produced a compound that matched the UV/VIS spectra of heterobactin, a siderophore previously only described in Rhodococcus and Nocardia. PMID:22038645

  9. Genome sequencing reveals complex secondary metabolome in the marine actinomycete Salinispora tropica

    PubMed Central

    Udwary, Daniel W.; Zeigler, Lisa; Asolkar, Ratnakar N.; Singan, Vasanth; Lapidus, Alla; Fenical, William; Jensen, Paul R.; Moore, Bradley S.

    2007-01-01

    Recent fermentation studies have identified actinomycetes of the marine-dwelling genus Salinispora as prolific natural product producers. To further evaluate their biosynthetic potential, we sequenced the 5,183,331-bp S. tropica CNB-440 circular genome and analyzed all identifiable secondary natural product gene clusters. Our analysis shows that S. tropica dedicates a large percentage of its genome (≈9.9%) to natural product assembly, which is greater than previous Streptomyces genome sequences as well as other natural product-producing actinomycetes. The S. tropica genome features polyketide synthase systems of every known formally classified family, nonribosomal peptide synthetases, and several hybrid clusters. Although a few clusters appear to encode molecules previously identified in Streptomyces species, the majority of the 17 biosynthetic loci are novel. Specific chemical information about putative and observed natural product molecules is presented and discussed. In addition, our bioinformatic analysis not only was critical for the structure elucidation of the polyene macrolactam salinilactam A, but its structural analysis aided the genome assembly of the highly repetitive slm loci. This study firmly establishes the genus Salinispora as a rich source of drug-like molecules and importantly reveals the powerful interplay between genomic analysis and traditional natural product isolation studies. PMID:17563368

  10. Genome sequencing reveals complex secondary metabolome in themarine actinomycete Salinispora tropica

    SciTech Connect

    Udwary, Daniel W.; Zeigler, Lisa; Asolkar, Ratnakar; Singan,Vasanth; Lapidus, Alla; Fenical, William; Jensen, Paul R.; Moore, BradleyS.

    2007-05-01

    Recent fermentation studies have identified actinomycetes ofthe marine-dwelling genus Salinispora as prolific natural productproducers. To further evaluate their biosynthetic potential, we analyzedall identifiable secondary natural product gene clusters from therecently sequenced 5,184,724 bp S. tropica CNB-440 circular genome. Ouranalysis shows that biosynthetic potential meets or exceeds that shown byprevious Streptomyces genome sequences as well as other naturalproduct-producing actinomycetes. The S. tropica genome features ninepolyketide synthase systems of every known formally classified family,non-ribosomal peptide synthetases and several hybrid clusters. While afew clusters appear to encode molecules previously identified inStreptomyces species,the majority of the 15 biosynthetic loci are novel.Specific chemical information about putative and observed natural productmolecules is presented and discussed. In addition, our bioinformaticanalysis was critical for the structure elucidation of the novelpolyenemacrolactam salinilactam A. This study demonstrates the potentialfor genomic analysis to complement and strengthen traditional naturalproduct isolation studies and firmly establishes the genus Salinispora asa rich source of novel drug-like molecules.

  11. Comparative genomics of actinomycetes with a focus on natural product biosynthetic genes

    PubMed Central

    2013-01-01

    Background Actinomycetes are a diverse group of medically, industrially and ecologically important bacteria, studied as much for the diseases they cause as for the cures they hold. The genomes of actinomycetes revealed that these bacteria have a large number of natural product gene clusters, although many of these are difficult to tie to products in the laboratory. Large scale comparisons of these clusters are difficult to perform due to the presence of highly similar repeated domains in the most common biosynthetic machinery: polyketide synthases (PKSs) and nonribosomal peptide synthetases (NRPSs). Results We have used comparative genomics to provide an overview of the genomic features of a set of 102 closed genomes from this important group of bacteria with a focus on natural product biosynthetic genes. We have focused on well-represented genera and determine the occurrence of gene cluster families therein. Conservation of natural product gene clusters within Mycobacterium, Streptomyces and Frankia suggest crucial roles for natural products in the biology of each genus. The abundance of natural product classes is also found to vary greatly between genera, revealing underlying patterns that are not yet understood. Conclusions A large-scale analysis of natural product gene clusters presents a useful foundation for hypothesis formulation that is currently underutilized in the field. Such studies will be increasingly necessary to study the diversity and ecology of natural products as the number of genome sequences available continues to grow. PMID:24020438

  12. Structural and functional properties of actinomycetal communities in chernozems and saline soils of Ukraine

    NASA Astrophysics Data System (ADS)

    Grishko, V. N.; Syshchikova, O. V.

    2010-02-01

    In the profiles of ordinary and southern chernozems, the total numbers of amylolytic microorganisms and actinomycetes decreased with the depth by 2.4-4.2 and 3.4 times, respectively; in the profiles of solonetz and solonchak soils, by 4.2-5.3 and 4.8 times, respectively. In the genetic horizons of the ordinary and southern chernozems, the share of actinomycetes amounted to 29-30% of the total population of microorganisms; in the saline soils, it increases with the depth from 23 to 43%. In the chernozems, Streptomyces violaceomaculatus (Roseus section), St. sporoherbeus (Azureus), St. aerionidulus (Cinereus), St. enduracidicus (Cinereus), and St. grisinus (Cinereus) predominated; in the saline soils, St. violaceomaculatus and St. aerionidulus prevailed. In the ordinary chernozem, the Berger-Parker index was 1.5 times higher than in the southern chernozem. High similarity was found between the streptomycete communities in the chernozems (the Sorensen coefficient was 0.78). In the solonetzes, the species richness of the streptomycetes was higher by 1.7 times than in the solonchaks. In the chernozems, the similarity of the streptomycete communities was higher than in the solonchaks (0.78 and 0.60, respectively).

  13. Phosphatic precipitates associated with actinomycetes in speleothems from Grand Cayman, British West Indies

    NASA Astrophysics Data System (ADS)

    Jones, Brian

    2009-07-01

    Calcitic speleothems from a cave located on the north central coast of Grand Cayman commonly include corrosion surfaces that developed when calcite precipitation ceased and corrosion mediated by condensates became the operative process. Dissolution features associated with these surfaces, including etched crystal surfaces, microcavities, and solution-widened boundaries between crystals, are commonly occupied by microbes and microbial mats that have been replaced by calcium phosphate and/or coated with calcium phosphate. No mineralized microbes were found in the calcite crystals that form the speleothems. The morphology of the mineralized hyphae (eight morphotypes) and spores (nine morphotypes) are indicative of actinomycetes, a group of microbes that are ideally adapted to life in oligotrophic cave environs. Superb preservation of the delicate hyphae, aerial hyphae, and delicate ornamentation on the hyphae and spores indicate that the microbes underwent rapid mineralized while close to their original life positions. Although these actinomycetes were extremely susceptible to replacement by calcium phosphate, there is no evidence that they directly or indirectly controlled precipitation. Nevertheless, the association between the P-rich precipitates and microbes shows that the use of phosphorus as a proxy for seasonal climate changes in paleoclimate analyses must be treated with caution.

  14. Aureoverticillactam, a novel 22-atom macrocyclic lactam from the marine actinomycete Streptomyces aureoverticillatus.

    PubMed

    Mitchell, Scott S; Nicholson, Benjamin; Teisan, Sy; Lam, Kin S; Potts, Barbara C M

    2004-08-01

    During the course of our screening program designed to discover novel anticancer and anti-infective agents from marine microorganisms, a strain of Streptomyces aureoverticillatus (NPS001583) isolated from a marine sediment was found to produce a novel macrocyclic lactam with cytotoxicity against various tumor cell lines. Using extensive MS, UV, and NMR spectral analyses, the structure has been established as compound 1, aureoverticillactam, a 22-atom macrocyclic lactam incorporating both triene and tetraene conjugated olefins. PMID:15332863

  15. Streptomonospora tuzyakensis sp. nov., a halophilic actinomycete isolated from saline soil.

    PubMed

    Tatar, Demet; Guven, Kiymet; Inan, Kadriye; Cetin, Demet; Belduz, Ali Osman; Sahin, Nevzat

    2016-01-01

    A novel actinobacterium, designated strain BN506(T), was isolated from soil collected from Tuz (Salt) Lake, Konya, Turkey, and was characterised to determine its taxonomic position. The isolate was found to have morphological and chemotaxonomic properties associated with members of the genus Streptomonospora. The isolate was found to grow optimally at 37 °C and in the presence of 10 % (w/v) NaCl but not in the absence of NaCl. Phylogenetic analyses based on an almost-complete 16S rRNA gene sequences indicated that isolate is closely related to members of the genus Streptomonospora and forms a distinct phyletic line in the Streptomonospora phylogenetic tree. Strain BN506(T) is closely related to Streptomonospora halophila YIM 91355(T) (98.1 % sequence similarity). Sequence similarities with other type strains of the genus Streptomyces were lower than 98.0 %. The cell wall of the novel strain was found to contain meso-diaminopimelic acid. Whole cell hydrolysates were found to contain galactose, glucose and ribose. The predominant menaquinone was identified as MK-10(H8) (57.0 %). The polar lipids detected were identified as diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine. The major fatty acids were found to be anteiso-C17:0, iso-C16:0 and 10 methyl C18:0. Based on 16S rRNA gene sequence analysis, DNA-DNA relatedness, phenotypic characteristics and chemotaxonomic data, strain BN506(T) was identified as a member of a novel species of the genus Streptomonospora, for which the name Streptomonospora tuzyakensis sp. nov. (type strain BN506(T) = DSM 45930(T) = KCTC 29210(T)) is proposed. PMID:26459342

  16. Influence of mode of storage and drying of fodder on thermophilic actinomycete aerocontamination in dairy farms of the Doubs region of France.

    PubMed Central

    Dalphin, J C; Pernet, D; Reboux, G; Martinez, J; Dubiez, A; Barale, T; Depierre, A

    1991-01-01

    Airborne contamination by thermophilic actinomycetes, micromycetes and Gram negative bacteria was determined on 34 dairy farms and related to fodder drying and storage methods. Eighteen farms had a barn drying system, eight with additional heating; the remaining 16 had traditional fodder storage methods. Three air samples were obtained for each farm with a six stage Andersen sampler. The thermophilic actinomycetes were identified as Streptomyces and the dominant micromycetes as Aspergillus spp; there was no relation between the levels of these organisms. There were fewer thermophilic actinomycete colonies per Petri dish (stage 5 on the Anderson sampler) on farms with barn drying than on those with traditional storage (median (range) 7 (0-2628) and 56 (4-2628) respectively). The three farms where no thermophilic actinomycetes were found had barn drying with heating and the four most modern farms had lower thermophilic actinomycete colony counts than the others (median (range) 3 (0-10) and 48 (0-2628)). The level of thermophilic actinomycetes and, to a lesser degree, of micromycetes was higher where the farmer had farmer's lung. Thermophilic actinomycetes of the genus Streptomyces are probably the antigens associated with farmer's lung in the Doubs, and modern farms with barn drying and heating furnish some protection against this disease. PMID:1948788

  17. Haloglycomyces albus gen. nov., sp. nov., a halophilic, filamentous actinomycete of the family Glycomycetaceae.

    PubMed

    Guan, Tong-Wei; Tang, Shu-Kun; Wu, Jin-Yuan; Zhi, Xiao-Yang; Xu, Li-Hua; Zhang, Li-Li; Li, Wen-Jun

    2009-06-01

    A novel halophilic actinobacterium, designated YIM 92370(T), was isolated from a hypersaline habitat in Xinjiang Province, north-west China. The strain was aerobic, Gram-positive-staining and halophilic, with an optimum NaCl concentration for growth of 8-12 % (w/v). The whole-cell sugar pattern consisted of ribose, xylose and glucose. The predominant menaquinone was MK-9(H(4)) and the major fatty acids were iso-C(16 : 0), iso-C(17 : 0) and anteiso-C(17 : 0). The phospholipid pattern consisted of phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, two unknown phosphoglycolipids and one unknown phospholipid. The G+C content of the genomic DNA was 60.8 mol%. Phylogenetic analysis showed that strain YIM 92370(T) can be distinguished from representatives of Glycomyces and Stackebrandtia, the two existing genera in the family Glycomycetaceae, by low 16S rRNA gene sequence similarities (<93.7 %). Strain YIM 92370(T) therefore represents a novel genus and species of the family Glycomycetaceae, for which the name Haloglycomyces albus gen. nov., sp. nov. is proposed. The type strain of Haloglycomyces albus is YIM 92370(T) (=DSM 45210(T) =KCTC 19481(T)). PMID:19502305

  18. Optimization of Magnetosome Production and Growth by the Magnetotactic Vibrio Magnetovibrio blakemorei Strain MV-1 through a Statistics-Based Experimental Design

    PubMed Central

    Silva, Karen T.; Leão, Pedro E.; Abreu, Fernanda; López, Jimmy A.; Gutarra, Melissa L.; Farina, Marcos; Bazylinski, Dennis A.; Freire, Denise M. G.

    2013-01-01

    The growth and magnetosome production of the marine magnetotactic vibrio Magnetovibrio blakemorei strain MV-1 were optimized through a statistics-based experimental factorial design. In the optimized growth medium, maximum magnetite yields of 64.3 mg/liter in batch cultures and 26 mg/liter in a bioreactor were obtained. PMID:23396329

  19. Identification of a potential lead structure for designing new antimicrobials to treat infections caused by Staphylococcus epidermidis-resistant strains.

    PubMed

    Pinheiro, Luiz C S; Abreu, Paula A; Afonso, Ilidio F; Leal, Bruno; Corrêa, Luiz C D; Borges, Júlio C; Marques, Isakelly P; Lourenço, André L; Sathler, Plinio; dos Santos, Andre L; Medeiros, Cid A; Cabral, Lúcio M; Júnior, Maurício L O; Romeiro, Gilberto A; Ferreira, Vitor F; Rodrigues, Carlos R; Castro, Helena C; Bernardino, Alice M R

    2008-11-01

    Bacterial infections are a significant cause of morbidity and mortality among critically ill patients. The increase of antibiotic resistance in bacteria from human microbiota-such as Staphylococcus epidermidis, an important nosocomial pathogen that affects immunocompromised patients or those with indwelling devices-increased the desire for new antibiotics. In this study we designed, synthesized, and determined the antimicrobial activity of 27 thieno[2,3-b]pyridines (1, 2, 2a-2m, 3, 3a-3m) derivatives against a drug-resistant clinical S. epidermidis strain. In addition, we performed a structure-activity relationship analysis using a molecular modeling approach, and discuss the drug absorption, distribution, metabolism, excretion, and toxicity profile and Lipinski's "rule of five," which are tools to assess the relationship between structures and drug-like properties of active compounds. Our results showed that compound 3b (5-(1H-tetrazol-5-yl)-4-(3;-methylphenylamino)thieno[2,3-b]pyridine) was as active as oxacillin and chloramphenicol but with lower theoretical toxicity risks and a better drug likeness and drug score potential than chloramphenicol. All molecular modeling and biological results reinforced the promising profile of 3b for further experimental investigation and development of new antibacterial drugs. PMID:18810543

  20. Genetic Relationship among Worldwide Strains of Xanthomonas Causing Canker in Citrus Species and Design of New Primers for Their Identification by PCR†

    PubMed Central

    Cubero, J.; Graham, J. H.

    2002-01-01

    Partial sequence analysis of the ribosomal operon in Xanthomonas axonopodis allowed discrimination among strains causing the A, B, and C types of citrus bacterial canker (CBC) and quantification of the relationship of these organisms with other species and pathovars in the same genus. Sets of primers based on sequence differences in the internally transcribed spacer and on a sequence from the plasmid gene pthA involved in virulence were designed for specific identification of xanthomonads causing CBC diseases. The two sets were validated with a collection of Xanthomonas strains associated with citrus species. The primer set based on ribosomal sequences had a high level of specificity for X. axonopodis pv. citri, whereas the set based on the pthA gene was universal for all types of CBC organisms. Moreover, the relationships among worldwide Xanthomonas strains causing CBC were analyzed by amplification of repetitive sequences (enterobacterial repetitive intergenic consensus and BOX elements). Under specific conditions, pathotypes of these Xanthomonas strains could be discerned, and subgroups of the pathotypes were identified. Subgroups of strains were associated with certain geographic areas of the world, and on this basis the origin of type A strains introduced into Florida could be inferred. PMID:11872476

  1. Degradation of softwood, hardwood, and grass lignocelluloses by two Steptomyces strains

    SciTech Connect

    Antai, S.P.; Crawford, D.L.

    1981-08-01

    Two Streptomyces strains, S. viridosporus T7A and S. setonii 75Vi2, were grown on softwood, hardwood, and grass lignocelluloses, and lignocellulose decomposition was followed by monitoring substrate weight loss, lignin loss, and carbohydrate loss over time. Results showed that both Streptomyces strains substantially degraded both the lignin and the carbohydrate components of each lignocellulose; however, these actinomycetes were more efficient decomposers of grass lignocelluloses than of hardwood or softwood lignocelluloses. In particular, these Streptomyces strains were more efficient decomposers of grass lignins than of hardwood or softwood lignins.

  2. Impact of variation in acute virulence of BVDV1 strains on design of better vaccine efficacy challenge models

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to antigenic differences between BVDV1 and BVDV2 strains both pestivirus species are included in U.S. vaccines. The efficacy of these vaccines in preventing acute infections is evaluated based on reduction of clinical disease. While high virulence BVDV2 strains are used in U.S. vaccine efficac...

  3. Design and application of a fiber Bragg grating strain sensor with enhanced sensitivity in the small-scale dam model

    NASA Astrophysics Data System (ADS)

    Ren, Liang; Chen, Jianyun; Li, Hong-Nan; Song, Gangbing; Ji, Xueheng

    2009-03-01

    Accurate measurement of strain variation and effective prediction of failure within models have been major objectives for strain sensors in dam model tests. In this paper, a fiber Bragg grating (FBG) strain sensor with enhanced strain sensitivity that is packaged by two gripper tubes is presented and applied in the seismic tests of a small-scale dam model. This paper discusses the principle of enhanced sensitivity of the FBG strain sensor. Calibration experiments and reliability tests were conducted to evaluate the sensor's strain transferring characteristics on plates of different material. This paper also investigates the applicability of the FBG strain sensors in seismic tests of a dam model by conducting a comparison between the test measurements of FBG sensors and analytical predictions, monitoring the failure progress and predicting the cracking inside the dam model. Results of the dam model tests prove that the FBG strain sensor has the advantages of small size, high precision, and embeddability. It has a promising potential in the cracking and failure monitoring and identification of the dam model.

  4. Switching antibiotics production on and off in actinomycetes by an IclR family transcriptional regulator from Streptomyces peucetius ATCC 27952.

    PubMed

    Chaudhary, Amit Kumar; Singh, Bijay; Maharjan, Sushila; Jha, Amit Kumar; Kim, Byung-Gee; Sohng, Jae Kyung

    2014-08-01

    Doxorubicin, produced by Streptomyces peucetius ATCC 27952, is tightly regulated by dnrO, dnrN, and dnrI regulators. Genome mining of S. peucetius revealed the presence of the IclR (doxR) type family of transcription regulator mediating the signal-dependent expression of operons at the nonribosomal peptide synthetase gene cluster. Overexpression of doxR in native strain strongly repressed the drug production. Furthermore, it also had a negative effect on the regulatory system of doxorubicin, wherein the transcript of dnrI was reduced to the maximum level in comparision with the other two. Interestingly, the overexpression of the same gene also had strong inhibitory effects on the production of actinorhodin (blue pigment) and undecylprodigiosin (red pigment) in Streptomyces coelicolor M145, herboxidiene production in Streptomyces chromofuscus ATCC 49982, and spinosyn production in Saccharopolyspora spinosa NRRL 18395, respectively. Moreover, DoxR exhibited pleiotropic effects on the production of blue and red pigments in S. coelicolor when grown in different agar media, wherein the production of blue pigment was inhibited in R2YE medium and the red pigment was inhibited in YEME medium. However, the production of both blue and red pigments from S. coelicolor harboring doxR was halted in ISP2 medium, whereas S. coelicolor produced both pigmented antibiotics in the same plate. These consequences demonstrate that the on and off production of these antibiotics was not due to salt stress or media compositions, but was selectively controlled in actinomycetes. PMID:24786531

  5. Structural-functional specificity of the complexes of psychrotolerant soil actinomycetes

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Dubrova, M. S.; Zvyagintsev, D. G.

    2010-04-01

    The active growth and development of psychrotolerant actinomycetes take place in peat and podzolic soils of the tundra and taiga at temperatures below 10°C. The population density of psychrotolerant mycelial prokaryotes in these soils reaches thousands and tens of thousands of CFU/g of soil, and the length of their mycelium is up to 380 m/g of soil. The application of fluorescent in situ hybridization (the FISH method) demonstrated that the metabolically active psychrotolerant representatives of the phylogenetic group of Actinobacteria comprise up to 30% of the total number of bacteria in prokaryotic microbial communities of oligotrophic peat bog and podzolic soils. The portion of metabolically active mycelial actinobacteria exceeds the portion of unicellular actinobacteria. Psychrotolerant streptomycetes isolated from peat bog soils possess pectinolytic, amylolytic, and antagonistic activities at low temperatures (5°C).

  6. [Secondary metabolites from a deep-sea-derived actinomycete Micrococcus sp. R21].

    PubMed

    Peng, Kun; Su, Rui-qiang; Zhang, Gai-yun; Cheng, Xuan-xuan; Yang, Quan; Liu, Yong-hong; Yang, Xian-wen

    2015-06-01

    To investigate cytotoxic secondary metabolites of Micrococcus sp. R21, an actinomycete isolated from a deep-sea sediment (-6 310 m; 142 degrees 19. 9' E, 10 degrees 54. 6' N) of the Western Pacific Ocean, column chromatography was introduced over silica gel, ODS, and Sephadex LH-20. As a result, eight compounds were obtained. By mainly detailed analysis of the NMR data, their structures were elucidated as cyclo(4-hydroxy-L-Pro-L-leu) (1), cyclo(L-Pro-L-Gly) (2), cyclo( L-Pro-L-Ala) (3), cyclo( D-Pro-L-Leu) (4), N-β-acetyltryptamine (5), 2-hydroxybenzoic acid (6), and phenylacetic acid (7). Compound 1 exhibited weak cytotoxic activity against RAW264. 7 cells with IC50 value of 9.1 μmol x L(-1). PMID:26591527

  7. Semi-solid-state fermentation: a promising alternative for neomycin production by the actinomycete Streptomyces fradiae.

    PubMed

    Machado, Isabel; Teixeira, José A; Rodríguez-Couto, Susana

    2013-06-10

    The production of neomycin by the actinomycete Streptomyces fradiae, under semi-solid-state fermentation conditions was the main subject of this study. Two supports (nylon sponge and orange peelings) were tested in order to determine the most suitable one for the production of neomycin by the above-mentioned microorganism. Nylon sponge led to the highest neomycin production, reaching a maximum value of 13,903 μg/mL on the 10th day of cultivation. As a control, the same experiment was performed under submerged fermentation (SmF) conditions, without solid support. Here the production of neomycin by S. fradiae was about 55-fold lower (i.e. 250 μg/mL) than that obtained for SSF. PMID:23570968

  8. Iron acquisition in the marine actinomycete genus Salinispora is controlled by the desferrioxamine family of siderophores

    PubMed Central

    Roberts, Alexandra A.; Schultz, Andrew W.; Kersten, Roland D.; Dorrestein, Pieter C.; Moore, Bradley S.

    2012-01-01

    Many bacteria produce siderophores for sequestration of growth-essential iron. Analysis of the Salinispora genomes suggests that these marine actinomycetes support multiple hydroxamate- and phenolate-type siderophore pathways. We isolated and characterized desferrioxamines (DFOs) B and E from all three recognized Salinispora species and linked their biosyntheses in S. tropica CNB-440 and S. arenicola CNS-205 to the des locus through PCR-directed mutagenesis. Gene inactivation of the predicted iron-chelator biosynthetic loci sid2-4 did not abolish siderophore chemistry. Additionally, these pathways could not restore the native growth characteristics of the des mutants in iron-limited media, although differential iron-dependent regulation was observed for the yersiniabactin-like sid2 pathway. Consequently, this study indicates that DFOs are the primary siderophores in laboratory cultures of Salinispora. PMID:22812504

  9. Storage of Stock Cultures of Filamentous Fungi, Yeasts, and Some Aerobic Actinomycetes in Sterile Distilled Water

    PubMed Central

    McGinnis, M. R.; Padhye, A. A.; Ajello, L.

    1974-01-01

    Castellani's procedure for maintaining cultures of filamentous fungi and yeasts in sterile distilled water was evaluated. Four hundred and seventeen isolates of 147 species belonging to 66 genera of filamentous fungi, yeasts, and aerobic actinomycetes were maintained in sterile distilled water at room temperature over periods ranging from 12 to 60 months in four independent experiments. Of the 417 cultures, 389 (93%) survived storage in sterile distilled water. The selection of good sporulating cultures and sufficient inoculum consisting of spores and hyphae suspended in sterile distilled water were the most important factors influencing survival in water over a longer period of time. The technique was found to be simple, inexpensive, and reliable. PMID:4854418

  10. Microbisporicin gene cluster reveals unusual features of lantibiotic biosynthesis in actinomycetes

    PubMed Central

    Foulston, Lucy C.; Bibb, Mervyn J.

    2010-01-01

    Lantibiotics are ribosomally synthesized, posttranslationally modified peptide antibiotics. The biosynthetic gene cluster for microbisporicin, a potent lantibiotic produced by the actinomycete Microbispora corallina containing chlorinated tryptophan and dihydroxyproline residues, was identified by genome scanning and isolated from an M. corallina cosmid library. Heterologous expression in Nonomuraea sp. ATCC 39727 confirmed that all of the genes required for microbisporicin biosynthesis were present in the cluster. Deletion, in M. corallina, of the gene (mibA) predicted to encode the prepropeptide abolished microbisporicin production. Further deletion analysis revealed insights into the biosynthesis of this unusual and potentially clinically useful lantibiotic, shedding light on mechanisms of regulation and self-resistance. In particular, we report an example of the involvement of a tryptophan halogenase in the modification of a ribosomally synthesized peptide and the pathway-specific regulation of an antibiotic biosynthetic gene cluster by an extracytoplasmic function σ factor–anti-σ factor complex. PMID:20628010

  11. Design of a new stretching apparatus and the effects of cyclic strain and substratum on mouse lung epithelial-12 cells.

    PubMed

    Arold, Stephen P; Wong, Joyce Y; Suki, Bela

    2007-07-01

    The pulmonary epithelium is exposed to mechanical strains during normal breathing or mechanical ventilation. While important for the regulation of cellular processes, excessive strains damage epithelial cells. To investigate the effects of strain on the epithelium, we developed a stretching device to apply equi-biaxial strains to cells cultured on elastic membranes. Following device validation, we exposed a murine epithelial cell line (MLE-12) to 30 min of cyclic stretch with 0, 25, 50, 75 and 100% change in surface area on pronectin or type I collagen coated membranes. Following stretch, we assessed cell viability using fluorescent immunocytochemisty and surfactant secretion using [(3)H] labeled phosphatidylcholine (PC). Cell injury increased with increasing strain with cells on pronectin showing more injury than on type I collagen. Stretching had no effect on surfactant secretion on either substratum suggesting MLE-12 cells are a poor model for stretch-induced surfactant secretion. The cells grown on pronectin, however, demonstrated a 3-fold increase in surfactant secretion compared to those grown on type I collagen at all strains. This suggests that, while this cell line does not demonstrate stretch-induced surfactant secretion, the underlying extracellular matrix plays a crucial factor in both cell death and signal transduction in response to strain. PMID:17578668

  12. Relationship between Glycopeptide Production and Resistance in the Actinomycete Nonomuraea sp. ATCC 39727

    PubMed Central

    Binda, Elisa; Carrano, Lucia; Bibb, Mervyn; Marinelli, Flavia

    2014-01-01

    Glycopeptides and β-lactams inhibit bacterial peptidoglycan synthesis in Gram-positive bacteria; resistance to these antibiotics is studied intensively in enterococci and staphylococci because of their relevance to infectious disease. Much less is known about antibiotic resistance in glycopeptide-producing actinomycetes that are likely to represent the evolutionary source of resistance determinants found in bacterial pathogens. Nonomuraea sp. ATCC 39727, the producer of A40926 (the precursor for the semisynthetic dalbavancin), does not harbor the canonical vanHAX genes. Consequently, we investigated the role of the β-lactam-sensitive d,d-peptidase/d,d-carboxypeptidase encoded by vanYn, the only van-like gene found in the A40926 biosynthetic gene cluster, in conferring immunity to the antibiotic in Nonomuraea sp. ATCC 39727. Taking advantage of the tools developed recently to genetically manipulate this uncommon actinomycete, we varied vanYn gene dosage and expressed vanHatAatXat from the teicoplanin producer Actinoplanes teichomyceticus in Nonomuraea sp. ATCC 39727. Knocking out vanYn, complementing a vanYn mutant, or duplicating vanYn had no effect on growth but influenced antibiotic resistance and, in the cases of complementation and duplication, antibiotic production. Nonomuraea sp. ATCC 39727 was found to be resistant to penicillins, but its glycopeptide resistance was diminished in the presence of penicillin G, which inhibits VanYn activity. The heterologous expression of vanHatAatXat increased A40926 resistance in Nonomuraea sp. ATCC 39727 but did not increase antibiotic production, indicating that the level of antibiotic production is not directly determined by the level of resistance. The vanYn-based self-resistance in Nonomuraea sp. ATCC 39727 resembles the glycopeptide resistance mechanism described recently in mutants of Enterococcus faecium selected in vitro for high-level resistance to glycopeptides and penicillins. PMID:24957828

  13. Design of a pulse-type strain gauge balance for a long-test-duration hypersonic shock tunnel

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Liu, Y.; Jiang, Z.

    2016-01-01

    When the measurement of aerodynamic forces is conducted in a hypersonic shock tunnel, the inertial forces lead to low-frequency vibrations of the model, and its motion cannot be addressed through digital filtering because a sufficient number of cycles cannot be obtained during a tunnel run. This finding implies restrictions on the model size and mass as the natural frequencies are inversely proportional to the length scale of the model. Therefore, the force measurement still has many problems, particularly for large and heavy models. Different structures of a strain gauge balance (SGB) are proposed and designed, and the measurement element is further optimized to overcome the difficulties encountered during the measurement of aerodynamic forces in a shock tunnel. The motivation for this study is to assess the structural performance of the SGB used in a long-test-duration JF12 hypersonic shock tunnel, which has more than 100 ms of test time. Force tests were conducted for a large-scale cone with a 10° semivertex angle and a length of 0.75 m in the JF12 long-test-duration shock tunnel. The finite element method was used for the analysis of the vibrational characteristics of the Model-Balance-Sting System (MBSS) to ensure a sufficient number of cycles, particularly for the axial force signal during a shock tunnel run. The higher-stiffness SGB used in the test shows good performance, wherein the frequency of the MBSS increases because of the stiff construction of the balance. The experimental results are compared with the data obtained in another wind tunnel and exhibit good agreement at M = 7 and α =5°.

  14. A multiscale and multiphysics model of strain development in a 1.5 T MRI magnet designed with 36 filament composite MgB2 superconducting wire

    NASA Astrophysics Data System (ADS)

    Amin, Abdullah Al; Baig, Tanvir; Deissler, Robert J.; Yao, Zhen; Tomsic, Michael; Doll, David; Akkus, Ozan; Martens, Michael

    2016-05-01

    High temperature superconductors such as MgB2 focus on conduction cooling of electromagnets that eliminates the use of liquid helium. With the recent advances in the strain sustainability of MgB2, a full body 1.5 T conduction cooled magnetic resonance imaging (MRI) magnet shows promise. In this article, a 36 filament MgB2 superconducting wire is considered for a 1.5 T full-body MRI system and is analyzed in terms of strain development. In order to facilitate analysis, this composite wire is homogenized and the orthotropic wire material properties are employed to solve for strain development using a 2D-axisymmetric finite element analysis (FEA) model of the entire set of MRI magnet. The entire multiscale multiphysics analysis is considered from the wire to the magnet bundles addressing winding, cooling and electromagnetic excitation. The FEA solution is verified with proven analytical equations and acceptable agreement is reported. The results show a maximum mechanical strain development of 0.06% that is within the failure criteria of -0.6% to 0.4% (-0.3% to 0.2% for design) for the 36 filament MgB2 wire. Therefore, the study indicates the safe operation of the conduction cooled MgB2 based MRI magnet as far as strain development is concerned.

  15. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    NASA Astrophysics Data System (ADS)

    Wicaksono, D. H. B.; Zhang, L.-J.; Pandraud, G.; French, P. J.; Vincent, J. F. V.

    2006-04-01

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter ~10 µm in a relatively stiff material of insect's exocuticle (E = ~109 Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating- hole- features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, thorugh-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membranein- recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor.

  16. Design procedures for Strain Hardening Cement Composites (SHCC) and measurement of their shear properties by mechanical and 2-D Digital Image Correlation (DIC) method

    NASA Astrophysics Data System (ADS)

    Aswani, Karan

    The main objective of this study is to investigate the behaviour and applications of strain hardening cement composites (SHCC). Application of SHCC for use in slabs of common configurations was studied and design procedures are prepared by employing yield line theory and integrating it with simplified tri-linear model developed in Arizona State University by Dr. Barzin Mobasher and Dr. Chote Soranakom. Intrinsic material property of moment-curvature response for SHCC was used to derive the relationship between applied load and deflection in a two-step process involving the limit state analysis and kinematically admissible displacements. For application of SHCC in structures such as shear walls, tensile and shear properties are necessary for design. Lot of research has already been done to study the tensile properties and therefore shear property study was undertaken to prepare a design guide. Shear response of textile reinforced concrete was investigated based on picture frame shear test method. The effects of orientation, volume of cement paste per layer, planar cross-section and volume fraction of textiles were investigated. Pultrusion was used for the production of textile reinforced concrete. It is an automated set-up with low equipment cost which provides uniform production and smooth final surface of the TRC. A 3-D optical non-contacting deformation measurement technique of digital image correlation (DIC) was used to conduct the image analysis on the shear samples by means of tracking the displacement field through comparison between the reference image and deformed images. DIC successfully obtained full-field strain distribution, displacement and strain versus time responses, demonstrated the bonding mechanism from perspective of strain field, and gave a relation between shear angle and shear strain.

  17. Design and proposal of dual line-of-defense perimeter watchdog incorporating optimally designed FBG based accelerometers and strain sensors using single optical fiber

    NASA Astrophysics Data System (ADS)

    Khan, Mohd. Mansoor; Sonkar, Ramesh Kumar

    2015-06-01

    Paper presents Opto-Mechanical intrusion sensor fence with FBGs attached to mechanical accelerometers and strain sensors, optimized on SolidWorks 2013 for desired frequency to 35 Hz, picking up accelerations/ strains and its deployment for perimeter security. The accelerometer structure consists of inertial mass supported by an L-shaped modified cantilever beam having non-uniform cross section area connected to base by a thin neck element which acts as strain concentrated centre hence an optimum zone for FBG sensors placement. Bragg wavelength shifts were obtained on Optigrating software for the obtained strain values on mechanical assembly of fence. CFD wind analysis is performed on the assembly to obtain the spot for accelerometer's placement to avoid false alarms up to wind velocities of 20 m/s.

  18. Study of the diversity of culturable actinomycetes in the North Pacific and Caribbean coasts of Costa Rica

    PubMed Central

    Solano, Godofredo; Rojas-Jiménez, Keilor; Jaspars, Marcel

    2011-01-01

    In this study, 137 actinomycetes were isolated from subtidal marine sediments in the North Pacific and Caribbean coasts of Costa Rica. Bioinformatics analysis of the 16S rRNA gene sequences assigned the isolates to 15 families and 21 genera. Streptomyces was the dominant genus while the remaining 20 genera were poorly represented. Nearly 70% of the phylotypes presented a coastal-restricted distribution whereas the other 30% were common inhabitants of both shores. The coastal tropical waters of Costa Rica showed a high diversity of actinomycetes, both in terms of the number of species and phylogenetic composition, although significant differences were observed between and within shores. The observed pattern of species distribution might be the result of several factors including the characteristics of the ecosystems, presence of endemic species and the influence of terrestrial runoff. PMID:19365710

  19. Transformation of 2,4,6-trinitrotoluene (TNT) by actinomycetes isolated from TNT-contaminated and uncontaminated environments

    SciTech Connect

    Pasti-Grigsby, M.B.; Lewis, T.A.; Crawford, D.L.; Crawford, R.L.

    1996-03-01

    Biotransformation of TNT has been reported under both aerobic and anaerobic conditions. Actinomycetes are important decomposers in composts. This study examines the tolerance of acitomycete cultures, isolated from both TNT-contaminated and uncontaminated environments for different concentrations to TNT, determined how selected isolates transform TNT, and examined whether such TNT transformations were constitutive or induced by exposure to TNT. 33 refs., 1 figs., 1 tab.

  20. Distribution and generic composition of culturable marine actinomycetes from the sediments of Indian continental slope of Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Das, Surajit; Lyla, P. S.; Ajmal Khan, S.

    2008-05-01

    Actinomycetes population from continental slope sediment of the Bay of Bengal was studied. Samples were collected during two voyages of FORV Sagar Sampada in 2004 (May-June) and 2005 (July) respectively from 11 transects (each transect had ca. 200 m, 500 m, and 1 000 m depth stations). The physicochemical parameters of overlying water, and sediment samples were also recorded. The actinomycete population ranged from 5.17 to 51.94 CFU/g dry sediment weight and 9.38 to 45.22 CFU/g dry sediment weight during the two cruises respectively. No actinomycete colony was isolated from stations in 1 000 m depth. Two-way analysis of variance showed significant variation among stations (ANOVA two-way, P<0.05), but no significance was found between the two cruises (ANOVA two-way, P<0.05). Populations in stations in 500 m depth in both cruises were higher than that of 200 m depth stations with statistically insignificant difference (ANOVA two-way, P>0.05). Three actinomycetes genera were identified. Streptomyces was found to be the dominating one in both the cruises, followed by Micromonospora, and Actinomyces. The spore of Streptomyces isolates showed the abundance in spiral spore chain. Spore surface was smooth. Multiple regression analysis revealed that the influencing physico-chemical factors were sediment pH, sediment temperature, TOC, porosity, salinity, and pressure. The media used in the present study was prepared with seawater. Thus, they may represent an autochthonous marine flora and deny the theory of land runoff carriage into the sea for adaptation to the salinity of the seawater and sediments.

  1. In situ identification of nocardioform actinomycetes in activated sludge using fluorescent rRNA-targeted oligonucleotide probes.

    PubMed

    Schuppler, M; Wagner, M; Schön, G; Göbel, U B

    1998-01-01

    Hitherto, few environmental samples have been investigated by a 'full cycle rRNA analysis'. Here the results of in situ hybridization experiments with specific rRNA-targeted oligonucleotide probes developed on the basis of new sequences derived from a previously described comparative 16S rRNA analysis of nocardioform actinomycetes in activated sludge are reported. Application of the specific probes enabled identification and discrimination of the distinct populations of nocardioform actinomycetes in activated sludge. One of the specific probes (DLP) detected rod-shaped bacteria which were found in 13 of the 16 investigated sludge samples from various wastewater treatment plants, suggesting their importance in the wastewater treatment process. Another probe (GLP2) hybridized with typically branched filaments of nocardioforms mainly found in samples from enhanced biological phosphorus removal plants, suggesting that these bacteria are involved in sludge foaming. The combination of in situ hybridization with fluorescently labelled rRNA-targeted oligonucleotide probes and confocal laser scanning microscopy improved the detection of nocardioform actinomycetes, which often showed only weak signals inside the activated-sludge flocs. PMID:9467916

  2. Evaluation of antimicrobial activity of the endophytic actinomycete R18(6) against multiresistant Gram-negative bacteria.

    PubMed

    Carvalho, Tiele; Van Der Sand, Sueli

    2016-03-01

    Endophytic actinomycetes are promising sources of antimicrobial substances. This study evaluates the activity of metabolites produced by the endophytic actinomycete R18(6) against Gram-negative bacteria multiresistant to antimicrobials. R18(6) isolate was grown in submerged cultures under different conditions: carbon source, temperature, pH and incubation time to optimize antimicrobials production. The actinomycete grown in base medium supplemented with 1% glucose, pH 6.5 and incubation at 30 ºC for 96 h with shaking at 100 rpm, exhibited the highest activity against the used Gram-negative bacteria. Minimum inhibitory concentration (MIC) of the crude extract produced by the microorganism varied between 1/32 and 1/256. It had bactericide or bacteriostatic activity, depending on the Gram-negative organism. The active extract was stable at high temperatures, and unstable in medium containing proteolytic enzymes. Micromorphology of R18(6) was investigated by optical and scan microscopy, revealing that it was morphologically similar to the genusStreptomyces. PMID:26871499

  3. Nitrogen regulator GlnR controls uptake and utilization of non-phosphotransferase-system carbon sources in actinomycetes.

    PubMed

    Liao, Cheng-Heng; Yao, Lili; Xu, Ya; Liu, Wei-Bing; Zhou, Ying; Ye, Bang-Ce

    2015-12-22

    The regulatory mechanisms underlying the uptake and utilization of multiple types of carbohydrates in actinomycetes remain poorly understood. In this study, we show that GlnR (central regulator of nitrogen metabolism) serves as a universal regulator of nitrogen metabolism and plays an important, previously unknown role in controlling the transport of non-phosphotransferase-system (PTS) carbon sources in actinomycetes. It was observed that GlnR can directly interact with the promoters of most (13 of 20) carbohydrate ATP-binding cassette (ABC) transporter loci and can activate the transcription of these genes in response to nitrogen availability in industrial, erythromycin-producing Saccharopolyspora erythraea. Deletion of the glnR gene resulted in severe growth retardation under the culture conditions used, with select ABC-transported carbohydrates (maltose, sorbitol, mannitol, cellobiose, trehalose, or mannose) used as the sole carbon source. Furthermore, we found that GlnR-mediated regulation of carbohydrate transport was highly conserved in actinomycetes. These results demonstrate that GlnR serves a role beyond nitrogen metabolism, mediating critical functions in carbon metabolism and crosstalk of nitrogen- and carbon-metabolism pathways in response to the nutritional states of cells. These findings provide insights into the molecular regulation of transport and metabolism of non-PTS carbohydrates and reveal potential applications for the cofermentation of biomass-derived sugars in the production of biofuels and bio-based chemicals. PMID:26644570

  4. Structural and Functional Characterizations of SsgB, a Conserved Activator of Developmental Cell Division in Morphologically Complex Actinomycetes

    SciTech Connect

    Xu, Qingping; Traag, Bjørn A.; Willemse, Joost; McMullan, Daniel; Miller, Mitchell D.; Elsliger, Marc-André; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L.; Bakolitsa, Constantina; Carlton, Dennis; Chen, Connie; Chiu, Hsiu-Ju; Chruszcz, Maksymilian; Clayton, Thomas; Das, Debanu; Deller, Marc C.; Duan, Lian; Ellrott, Kyle; Ernst, Dustin; Farr, Carol L.; Feuerhelm, Julie; Grant, Joanna C.; Grzechnik, Anna; Grzechnik, Slawomir K.; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kozbial, Piotr; Krishna, S. Sri; Kumar, Abhinav; Marciano, David; Minor, Wladek; Mommaas, A. Mieke; Morse, Andrew T.; Nigoghossian, Edward; Nopakun, Amanda; Okach, Linda; Oommachen, Silvya; Paulsen, Jessica; Puckett, Christina; Reyes, Ron; Rife, Christopher L.; Sefcovic, Natasha; Tien, Henry J.; Trame, Christine B.; van den Bedem, Henry; Wang, Shuren; Weekes, Dana; Hodgson, Keith O.; Wooley, John; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.; van Wezel, Gilles P.

    2010-01-20

    SsgA-like proteins (SALPs) are a family of homologous cell division-related proteins that occur exclusively in morphologically complex actinomycetes. We show that SsgB, a subfamily of SALPs, is the archetypal SALP that is functionally conserved in all sporulating actinomycetes. Sporulation-specific cell division of Streptomyces coelicolor ssgB mutants is restored by introduction of distant ssgB orthologues from other actinomycetes. Interestingly, the number of septa (and spores) of the complemented null mutants is dictated by the specific ssgB orthologue that is expressed. The crystal structure of the SsgB from Thermobifida fusca was determined at 2.6 {angstrom} resolution and represents the first structure for this family. The structure revealed similarities to a class of eukaryotic 'whirly' single-stranded DNA/RNA-binding proteins. However, the electro-negative surface of the SALPs suggests that neither SsgB nor any of the other SALPs are likely to interact with nucleotide substrates. Instead, we show that a conserved hydrophobic surface is likely to be important for SALP function and suggest that proteins are the likely binding partners.

  5. Development of a genetic transformation system for benzene-tolerant Rhodococcus opacus strains.

    PubMed

    Na, Kyung-Su; Nagayasu, Kan; Kuroda, Akio; Takiguchi, Noboru; Ikeda, Tsukasa; Ohtake, Hisao; Kato, Junichi

    2005-04-01

    Rhodococcus opacus B-4 and B-9 are tolerant to various organic solvents including benzene, toluene, ethylbenzene, xylenes and styrene, and are suitable bacterial hosts for the production of chemical products from hydrophobic substrates. A 4.4-kb endogenous plasmid (pKNR 01) was isolated from R. opacus B-4 and sequenced completely. Plasmid pKNR 01 encodes proteins that share similarity to replication proteins from the enteric bacterial and actinomycete theta-replication plasmids. A 7.4-kb chimeric plasmid, designated pKNR 01.1, was constructed by fusing XhoI-digested pKNR 01 and Escherichia coli vector pSTV 28. Plasmid pKNR 01.1 had the ability to replicate in B-4 and B-9. A protocol for transformation of B-9 by electroporation was optimized employing pKNR 01.1. Frequencies of 4.1 x 10(5) transformants per mug of plasmid DNA were obtained for B-9 cells, whereas B-4 harboring naturally occurring pKNR 01 was transformed at lower frequencies (approximately 1 x 10(4) transformants per mug of plasmid DNA). Deletion analysis of pKNR 01.1 showed that the 1.9-kb SphI-XhoI region containing the repA and rep B genes and the 0.6-kb region upstream of repA was essential for plasmid maintenance in R. opacus strains. PMID:16233810

  6. Simulation-based design of a strained graphene field effect transistor incorporating the pseudo magnetic field effect

    SciTech Connect

    Souma, Satofumi Ueyama, Masayuki; Ogawa, Matsuto

    2014-05-26

    We present a numerical study on the performance of strained graphene-based field-effect transistors. A local strain less than 10% is applied over a central channel region of the graphene to induce the shift of the Dirac point in the channel region along the transverse momentum direction. The left and the right unstrained graphene regions are doped to be either n-type or p-type. By using the atomistic tight-binding model and a Green's function method, we predict that the gate voltage applied to the central strained graphene region can switch the drain current on and off with an on/off ratio of more than six orders of magnitude at room temperature. This is in spite of the absence of a bandgap in the strained channel region. Steeper subthreshold slopes below 60 mV/decade are also predicted at room temperature because of a mechanism similar to the band-to-band tunneling field-effect transistors.

  7. Designing and exploring active N'-[(5-nitrofuran-2-yl) methylene] substituted hydrazides against three Trypanosoma cruzi strains more prevalent in Chagas disease patients.

    PubMed

    Palace-Berl, Fanny; Pasqualoto, Kerly Fernanda Mesquita; Jorge, Salomão Dória; Zingales, Bianca; Zorzi, Rodrigo Rocha; Silva, Marcelo Nunes; Ferreira, Adilson Kleber; de Azevedo, Ricardo Alexandre; Teixeira, Sarah Fernandes; Tavares, Leoberto Costa

    2015-01-01

    Chagas disease affects around 8 million people worldwide and its treatment depends on only two nitroheterocyclic drugs, benznidazole (BZD) and nifurtimox (NFX). Both drugs have limited curative power in chronic phase of disease. Nifuroxazide (NF), a nitroheterocyclic drug, was used as lead to design a set of twenty one compounds in order to improve the anti-Trypanosoma cruzi activity. Lipinski's rules were considered in order to support drug-likeness designing. The set of N'-[(5-nitrofuran-2-yl) methylene] substituted hydrazides was assayed against three T. cruzi strains, which represent the discrete typing units more prevalent in human patients: Y (TcII), Silvio X10 cl1 (TcI), and Bug 2149 cl10 (TcV). All the derivatives, except one, showed enhanced trypanocidal activity against the three strains as compared to BZD. In the Y strain 62% of the compounds were more active than NFX. The most active compound was N'-((5-nitrofuran-2-yl) methylene)biphenyl-4-carbohydrazide (C20), which showed IC50 values of 1.17 ± 0.12 μM; 3.17 ± 0.32 μM; and 1.81 ± 0.18 μM for Y, Silvio X10 cl1, and Bug 2149 cl10 strains, respectively. Cytotoxicity assays with human fibroblast cells have demonstrated high selectivity indices for several compounds. Exploratory data analysis indicated that primarily topological, steric/geometric, and electronic properties have contributed to the discrimination of the set of investigated compounds. The findings can be helpful to drive the designing, and subsequently, the synthesis of additional promising drugs against Chagas disease. PMID:25899337

  8. Gordonia didemni sp. nov. an actinomycete isolated from the marine ascidium Didemnum sp.

    PubMed

    de Menezes, Cláudia Beatriz Afonso; Afonso, Rafael Sanches; de Souza, Wallace Rafael; Parma, Márcia; de Melo, Itamar Soares; Zucchi, Tiago Domingues; Fantinatti-Garboggini, Fabiana

    2016-02-01

    A novel actinobacterium, designated isolate B204(T), was isolated from a marine ascidian Didemnum sp., collected from São Paulo, Brazil, and its taxonomic position established using data from a polyphasic study. The organism showed a combination of chemotaxonomic and morphological characteristics consistent with its classification in the genus Gordonia and formed a distinct phyletic line in the Gordonia 16S rRNA gene tree. It was closely related to Gordonia terrae DSM 43249(T) (99.9 % 16S rRNA gene sequence similarity) and Gordonia lacunae DSM 45085(T) (99.3 % 16S rRNA gene sequence similarity) but was distinguished from these strains by a moderate level of DNA-DNA relatedness (63.0 and 54.7 %) and discriminatory phenotypic properties. Based on the data obtained, the isolate B204(T) (=CBMAI 1069(T) = DSM 46679(T)) should therefore be classified as the type strain of a novel species of the genus Gordonia, for which the name Gordonia didemni sp. nov. is proposed. PMID:26678782

  9. Interlaboratory standardization of the sandwich enzyme-linked immunosorbent assay designed for MATS, a rapid, reproducible method for estimating the strain coverage of investigational vaccines.

    PubMed

    Plikaytis, Brian D; Stella, Maria; Boccadifuoco, Giuseppe; DeTora, Lisa M; Agnusdei, Mauro; Santini, Laura; Brunelli, Brunella; Orlandi, Luca; Simmini, Isabella; Giuliani, Marzia; Ledroit, Morgan; Hong, Eva; Taha, Muhamed-Kheir; Ellie, Kim; Rajam, Gowrisankar; Carlone, George M; Claus, Heike; Vogel, Ulrich; Borrow, Ray; Findlow, Jamie; Gilchrist, Stefanie; Stefanelli, Paola; Fazio, Cecilia; Carannante, Anna; Oksnes, Jan; Fritzsønn, Elisabeth; Klem, Anne-Marie; Caugant, Dominique A; Abad, Raquel; Vázquez, Julio A; Rappuoli, Rino; Pizza, Mariagrazia; Donnelly, John J; Medini, Duccio

    2012-10-01

    The meningococcal antigen typing system (MATS) sandwich enzyme-linked immunosorbent assay (ELISA) was designed to measure the immunologic cross-reactivity and quantity of antigens in target strains of a pathogen. It was first used to measure the factor H-binding protein (fHbp), neisserial adhesin A (NadA), and neisserial heparin-binding antigen (NHBA) content of serogroup B meningococcal (MenB) isolates relative to a reference strain, or "relative potency" (RP). With the PorA genotype, the RPs were then used to assess strain coverage by 4CMenB, a multicomponent MenB vaccine. In preliminary studies, MATS accurately predicted killing in the serum bactericidal assay using human complement, an accepted correlate of protection for meningococcal vaccines. A study across seven laboratories assessed the reproducibility of RPs for fHbp, NadA, and NHBA and established qualification parameters for new laboratories. RPs were determined in replicate for 17 MenB reference strains at laboratories A to G. The reproducibility of RPs among laboratories and against consensus values across laboratories was evaluated using a mixed-model analysis of variance. Interlaboratory agreement was very good; the Pearson correlation coefficients, coefficients of accuracy, and concordance correlation coefficients exceeded 99%. The summary measures of reproducibility, expressed as between-laboratory coefficients of variation, were 7.85% (fHbp), 16.51% (NadA), and 12.60% (NHBA). The overall within-laboratory measures of variation adjusted for strain and laboratory were 19.8% (fHbp), 28.8% (NHBA), and 38.3% (NadA). The MATS ELISA was successfully transferred to six laboratories, and a further laboratory was successfully qualified. PMID:22875603

  10. Crystal structure analysis under uniaxial strain at low temperature using a unique design of four-axis x-ray diffractometer with a fixed sample

    SciTech Connect

    Kondo, Ryusuke; Kagoshima, Seiichi; Harada, Jimpei

    2005-09-15

    For the purpose of crystal structure analysis under uniaxial strain at low temperatures, we developed a pressure cell for uniaxial compression and a unique design of an x-ray diffractometer wherein both the x-ray source and the detector are capable of two-axial rotation with a fixed sample. This arrangement is advantageous to crystal structure analyses under extreme conditions that require a large and heavy apparatus. Using the present diffractometer, we performed the crystal structure analyses of the organic conductor, {alpha}-(BEDT-TTF){sub 2}I{sub 3} (BEDT-TTF denotes bis(ethylene)dithio-tetrathiafulvalene), under uniaxial strain and ambient pressure, and at room and low temperatures, and obtained results that were qualitatively consistent with those of resistivity measurements.

  11. Heterointerface design and strain tuning in epitaxial BiFeO3:CoFe2O4 nanocomposite films

    NASA Astrophysics Data System (ADS)

    Zhang, Wenrui; Fan, Meng; Li, Leigang; Chen, Aiping; Su, Qing; Jia, Quanxi; MacManus-Driscoll, Judith L.; Wang, Haiyan

    2015-11-01

    The ability to control the morphology of heterointerfaces with coupled functionalities is fascinating from both fundamental and technological perspectives. Here, using BiFeO3:CoFe2O4 vertically aligned nanocomposite (VAN) films as a model system, we demonstrate a simple and effective method to modulate the heterointerface and its morphology in nanocomposite films with pulsed laser deposition. By tuning the deposition frequency through thickness during film growth, both vertically straight and gradient heterointerfaces have been achieved. The modulated heterointerface is strongly correlated with strain tuning and interface coupling, and thus modifies the magnetic anisotropy, coercive fields, and ferroelectric switching behavior. This study provides a viable approach for tailoring the interface strain and coupling in VAN and achieving tunable physical properties.

  12. [Effects of actinomycetes agent on ginseng growth and rhizosphere soil microflora].

    PubMed

    Zhang, Hong-yan; Xue, Quan-hong; Shen, Guang-hui; Wang, Dong-sheng

    2013-08-01

    Taking the ginseng in Xiao Xing' an Mountains of Northeast China as test object, this paper studied the effects of applying Streptomyces pactum (Act12) on ginseng growth and on the soil microflora in root zone and root surface. After treated with Act12, the yield and quality of ginseng' s medicinal part improved, the induced enzyme activities in leaves and the root activity increased, and the numbers and proportions of soil bacteria and actinomycetes increased significantly while those of soil fungi decreased. Compared with the control, the soil microflora in treatment Act12 changed. The numbers of the dominant bacteria Pseudomonas fluorescens, Pseudomonas koreensis, and Microbacterium oxydans were much higher in root zone soil and root surface soil, and the pathogen Plectosphaerella cucumerina decreased in root zone soil and disappeared in root surface soil. These results suggested that the addition of Act12 could improve the soil microflora, enhance the resistance and root activity of ginseng plant, and increase the ginseng yield and its quality. PMID:24380350

  13. Field studies on two rock phosphate solubilizing actinomycete isolates as biofertilizer sources

    NASA Astrophysics Data System (ADS)

    Mba, Caroline C.

    1994-03-01

    Recently biotechnology is focusing attention on utilization of biological resources to solve a number of environmental problems such as soil fertility management. Results of microbial studies on earthworm compost in the University of Nigeria farm identified a number of rock phosphate solubilizing actinomycetes. Two of these, isclates 02 and 13, were found to be efficient rock phosphate (RP) solubilizers and fast-growing cellulolytic microbes producing extracellular hydrolase enzymes. In this preliminary field study the two microbial isolates were investigated with respect to their effects on the growth of soybean and egusi as well as their effect on the incidence of toxicity of poultry droppings. Application of these isolates in poultry manure-treated field plots, as microbial fertilizers, brought about yield increases of 43% and 17% with soybeans and 19% and 33% with egusi, respectively. Soil properties were also improved. With isolates 02 and 13, the soil available phosphorus increased at the five-leaf stage, while N-fixation in the soil increased by 45% or 11% relative to control. It was further observed that air-dried poultry manure after four days of incubation was still toxic to soybean. The toxic effect of the applied poultry manure was reduced or eliminated with microbial fertilizers 02 or 13, respectively. The beneficial effects of the microbial organic fertilizer are discussed. Justification for more intensive research on rock phosphate organic fertilizer is highlighted.

  14. Effects of marine actinomycete on the removal of a toxicity alga Phaeocystis globose in eutrophication waters.

    PubMed

    Zhang, Huajun; Zhang, Su; Peng, Yun; Li, Yi; Chen, Zhangran; Xu, Hong; Yu, Zhiming; Zheng, Wei; Zheng, Tianling

    2015-01-01

    Phaeocystis globosa blooms in eutrophication waters can cause severely damage in marine ecosystem and consequently influence human activities. This study investigated the effect and role of an algicidal actinomycete (Streptomyces sp. JS01) on the elimination process of P. globosa. JS01 supernatant could alter algal cell membrane permeability in 4 h when analyzed with flow cytometry. Reactive oxygen species (ROS) levels were 7.2 times higher than that at 0 h following exposure to JS01 supernatant for 8 h, which indicated that algal cells suffered from oxidative damage. The Fv/Fm value which could reflect photosystem II (PS II) electron flow status also decreased. Real-time PCR showed that the expression of the photosynthesis related genes psbA and rbcS were suppressed by JS01 supernatant, which might induce damage to PS II. Our results demonstrated that JS01 supernatant can change algal membrane permeability in a short time and then affect photosynthesis process, which might block the PS II electron transport chain to produce excessive ROS. This experiment demonstrated that Streptomyces sp. JS01 could eliminate harmful algae in marine waters efficiently and may be function as a harmful algal bloom controller material. PMID:26042109

  15. Effects of marine actinomycete on the removal of a toxicity alga Phaeocystis globose in eutrophication waters

    PubMed Central

    Zhang, Huajun; Zhang, Su; Peng, Yun; Li, Yi; Chen, Zhangran; Xu, Hong; Yu, Zhiming; Zheng, Wei; Zheng, Tianling

    2015-01-01

    Phaeocystis globosa blooms in eutrophication waters can cause severely damage in marine ecosystem and consequently influence human activities. This study investigated the effect and role of an algicidal actinomycete (Streptomyces sp. JS01) on the elimination process of P. globosa. JS01 supernatant could alter algal cell membrane permeability in 4 h when analyzed with flow cytometry. Reactive oxygen species (ROS) levels were 7.2 times higher than that at 0 h following exposure to JS01 supernatant for 8 h, which indicated that algal cells suffered from oxidative damage. The Fv/Fm value which could reflect photosystem II (PS II) electron flow status also decreased. Real-time PCR showed that the expression of the photosynthesis related genes psbA and rbcS were suppressed by JS01 supernatant, which might induce damage to PS II. Our results demonstrated that JS01 supernatant can change algal membrane permeability in a short time and then affect photosynthesis process, which might block the PS II electron transport chain to produce excessive ROS. This experiment demonstrated that Streptomyces sp. JS01 could eliminate harmful algae in marine waters efficiently and may be function as a harmful algal bloom controller material. PMID:26042109

  16. Genome Sequence and Analysis of the Soil Cellulolytic Actinomycete Thermobifida fusca YX

    SciTech Connect

    Lykidis, A; Mavromatis, K; Ivanova, N; Anderson, Iain; Land, Miriam L; DiBartolo, Genevieve; Martinez, Michele; Lapidus, Alla L.; Lucas, Susan; Copeland, A; Richardson, P M; Wilson, David B; Kyrpides, Nikos C

    2007-01-01

    Thermobifida fusca is a moderately thermophilic soil bacterium that belongs to Actinobacteria. It is a major degrader of plant cell walls and has been used as a model organism for the study of secreted, thermostable cellulases. The complete genome sequence showed that T. fusca has a single circular chromosome of 3,642,249 bp predicted to encode 3,117 proteins and 65 RNA species with a coding density of 85%. Genome analysis revealed the existence of 29 putative glycoside hydrolases in addition to the previously identified cellulases and xylanases. The glycosyl hydrolases include enzymes predicted to exhibit mainly dextran/starch- and xylan-degrading functions. T. fusca possesses two protein secretion systems: the sec general secretion system and the twin-arginine translocation system. Several of the secreted cellulases have sequence signatures indicating their secretion may be mediated by the twin-arginine translocation system. T. fusca has extensive transport systems for import of carbohydrates coupled to transcriptional regulators controlling the expression of the transporters and glycosylhydrolases. In addition to providing an overview of the physiology of a soil actinomycete, this study presents insights on the transcriptional regulation and secretion of cellulases which may facilitate the industrial exploitation of these systems.

  17. Biogenic gold nanotriangles from Saccharomonospora sp., an endophytic actinomycetes of Azadirachta indica A. Juss.

    NASA Astrophysics Data System (ADS)

    Verma, Vijay C.; Anand, Swechha; Ulrichs, Christian; Singh, Santosh K.

    2013-04-01

    Microbial biofabrication is emerging as eco-friendly, simpler, and reproducible alternative to chemical synthesis of metals and semiconductor nanoparticles, allowing generation of rare geometrical forms such as nanotriangles and nanoprisms. Highly confined nanostructures like triangles/prisms are interesting class of nanoparticles due to their unique optical properties exploitable in biomedical diagnostics and biosensors. Here, we report for the first time a single-step biological protocol for the synthesis of gold nanotriangles using extract of endophytic actinomycetes Saccharomonospora sp., isolated from surface sterilized root tissues of Azadirachta indica A. Juss., when incubated with an aqueous solution of chloroaurate ions (AuCl- 4/1 mM). Thin, flat occasionally prismatic gold nanotriangles were produced when aqueous chloroaurate ions reacted with the cell-free extract as well as with the biomass of endophytic Saccharomonospora. It was evidenced from sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis that proteins of 42 and 50 kD were involved in biosynthesis as well as in stabilization of the nanoparticles. The particle growth process was monitored by UV-vis spectroscopy, and the morphological characterization was carried out by transmission electron microscopy and atomic force microscopy together with X-ray powder diffractions. Although the exact mechanism for this shape-oriented synthesis is not clear so far, the possibility of achieving nanoparticle shape control in a microbial system is exciting.

  18. Genome Sequence and Analysis of the Soil Cellulolytic ActinomyceteThermobifida fusca

    SciTech Connect

    Lykidis, Athanasios; Mavromatis, Konstantinos; Ivanova, Natalia; Anderson, Iain; Land, Miriam; DiBartolo, Genevieve; Martinez, Michele; Lapidus, Alla; Lucas, Susan; Copeland, Alex; Richardson, Paul; Wilson,David B.; Kyrpides, Nikos

    2007-02-01

    Thermobifida fusca is a moderately thermophilic soilbacterium that belongs to Actinobacteria. 3 It is a major degrader ofplant cell walls and has been used as a model organism for the study of 4secreted, thermostable cellulases. The complete genome sequence showedthat T. fusca has a 5 single circular chromosome of 3642249 bp predictedto encode 3117 proteins and 65 RNA6 species with a coding densityof 85percent. Genome analysis revealed the existence of 29 putative 7glycoside hydrolases in addition to the previously identified cellulasesand xylanases. The 8 glycosyl hydrolases include enzymes predicted toexhibit mainly dextran/starch and xylan 9 degrading functions. T. fuscapossesses two protein secretion systems: the sec general secretion 10system and the twin-arginine translocation system. Several of thesecreted cellulases have 11 sequence signatures indicating theirsecretion may be mediated by the twin-arginine12 translocation system. T.fusca has extensive transport systems for import of carbohydrates 13coupled to transcriptional regulators controlling the expression of thetransporters and14 glycosylhydrolases. In addition to providing anoverview of the physiology of a soil 15 actinomycete, this study presentsinsights on the transcriptional regulation and secretion of16 cellulaseswhich may facilitate the industrial exploitation of thesesystems.

  19. Characterization of dusts collected from swine confinement buildings. [Verticillium sp. ; Actinomycetes

    SciTech Connect

    Donham, K.J.; Scallon, L.J.; Popendorf, W.; Treauhaft, M.W.; Roberts, R.D.

    1986-07-01

    The air in 21 different swine confinement buildings was sampled with 37 mm cassette filters with and without cyclone preselectors and with cascade impactors. Filter results yielded a mean total aerosol of 6.3 mg/m/sup 3/, a mean respirable aerosol of 0.5 mg/m/sup 3/; the geometric mean diameter was 2.9 microns. Cascade impactor measurements revealed a mean total aerosol of 7.6 mg/m/sup 3/, a respirable aerosol of 2.5 mg/m/sup 3/ and a mass median diameter of 9.6 microns. The two major constituents in these aerosols were grain particles and dried fecal matter. The grain particles were larger than fecal particles and proportionately more abundant in finishing buildings where 50 kg-100 kg animals are housed. Therefore the respirable fraction was less in finishing buildings than in farrowing and nursery buildings. Culturing of settled dusts yielded six different mold species, with the highest counts for Verticillium sp. (5 x 10/sup 2/ cfu/mg dry dust) grown at 37/sup 0/C. Thermophilic Actinomycetes and both gram negative and gram positive bacteria were isolated.

  20. The properties given at the time of publication for the designated type strain of Leifsonia rubra Reddy et al. 2003, CMS 76r, do not correspond with those of MTCC 4210, DSM 15304, CIP 107783 and JCM 12471 that are deposited as representing the type strain: Opinion 96. Judicial Commission of the International Committee on Systematics of Prokaryotes.

    PubMed

    Tindall, B J

    2014-10-01

    The Judicial Commission affirms that, according to information presented to it, the type strain of Leifsonia rubra Reddy et al. 2003 designated in the original publication as strain CMS 76r and deposited as MTCC 4210, DSM 15304, CIP 107783 and JCM 12471 does not have properties corresponding with those of the strains held in those collections under those accession numbers. The species Leifsonia rubra Reddy et al. 2003 was not represented by an authentic deposit of a type strain at the time of effective publication in the pages of the International Journal of Systematic and Evolutionary Microbiology. PMID:25288665

  1. The Genome Sequence of the Tomato-Pathogenic Actinomycete Clavibacter michiganensis subsp. michiganensis NCPPB382 Reveals a Large Island Involved in Pathogenicity▿ †

    PubMed Central

    Gartemann, Karl-Heinz; Abt, Birte; Bekel, Thomas; Burger, Annette; Engemann, Jutta; Flügel, Monika; Gaigalat, Lars; Goesmann, Alexander; Gräfen, Ines; Kalinowski, Jörn; Kaup, Olaf; Kirchner, Oliver; Krause, Lutz; Linke, Burkhard; McHardy, Alice; Meyer, Folker; Pohle, Sandra; Rückert, Christian; Schneiker, Susanne; Zellermann, Eva-Maria; Pühler, Alfred; Eichenlaub, Rudolf; Kaiser, Olaf; Bartels, Daniela

    2008-01-01

    Clavibacter michiganensis subsp. michiganensis is a plant-pathogenic actinomycete that causes bacterial wilt and canker of tomato. The nucleotide sequence of the genome of strain NCPPB382 was determined. The chromosome is circular, consists of 3.298 Mb, and has a high G+C content (72.6%). Annotation revealed 3,080 putative protein-encoding sequences; only 26 pseudogenes were detected. Two rrn operons, 45 tRNAs, and three small stable RNA genes were found. The two circular plasmids, pCM1 (27.4 kbp) and pCM2 (70.0 kbp), which carry pathogenicity genes and thus are essential for virulence, have lower G+C contents (66.5 and 67.6%, respectively). In contrast to the genome of the closely related organism Clavibacter michiganensis subsp. sepedonicus, the genome of C. michiganensis subsp. michiganensis lacks complete insertion elements and transposons. The 129-kb chp/tomA region with a low G+C content near the chromosomal origin of replication was shown to be necessary for pathogenicity. This region contains numerous genes encoding proteins involved in uptake and metabolism of sugars and several serine proteases. There is evidence that single genes located in this region, especially genes encoding serine proteases, are required for efficient colonization of the host. Although C. michiganensis subsp. michiganensis grows mainly in the xylem of tomato plants, no evidence for pronounced genome reduction was found. C. michiganensis subsp. michiganensis seems to have as many transporters and regulators as typical soil-inhabiting bacteria. However, the apparent lack of a sulfate reduction pathway, which makes C. michiganensis subsp. michiganensis dependent on reduced sulfur compounds for growth, is probably the reason for the poor survival of C. michiganensis subsp. michiganensis in soil. PMID:18192381

  2. The genome sequence of the tomato-pathogenic actinomycete Clavibacter michiganensis subsp. michiganensis NCPPB382 reveals a large island involved in pathogenicity.

    PubMed

    Gartemann, Karl-Heinz; Abt, Birte; Bekel, Thomas; Burger, Annette; Engemann, Jutta; Flügel, Monika; Gaigalat, Lars; Goesmann, Alexander; Gräfen, Ines; Kalinowski, Jörn; Kaup, Olaf; Kirchner, Oliver; Krause, Lutz; Linke, Burkhard; McHardy, Alice; Meyer, Folker; Pohle, Sandra; Rückert, Christian; Schneiker, Susanne; Zellermann, Eva-Maria; Pühler, Alfred; Eichenlaub, Rudolf; Kaiser, Olaf; Bartels, Daniela

    2008-03-01

    Clavibacter michiganensis subsp. michiganensis is a plant-pathogenic actinomycete that causes bacterial wilt and canker of tomato. The nucleotide sequence of the genome of strain NCPPB382 was determined. The chromosome is circular, consists of 3.298 Mb, and has a high G+C content (72.6%). Annotation revealed 3,080 putative protein-encoding sequences; only 26 pseudogenes were detected. Two rrn operons, 45 tRNAs, and three small stable RNA genes were found. The two circular plasmids, pCM1 (27.4 kbp) and pCM2 (70.0 kbp), which carry pathogenicity genes and thus are essential for virulence, have lower G+C contents (66.5 and 67.6%, respectively). In contrast to the genome of the closely related organism Clavibacter michiganensis subsp. sepedonicus, the genome of C. michiganensis subsp. michiganensis lacks complete insertion elements and transposons. The 129-kb chp/tomA region with a low G+C content near the chromosomal origin of replication was shown to be necessary for pathogenicity. This region contains numerous genes encoding proteins involved in uptake and metabolism of sugars and several serine proteases. There is evidence that single genes located in this region, especially genes encoding serine proteases, are required for efficient colonization of the host. Although C. michiganensis subsp. michiganensis grows mainly in the xylem of tomato plants, no evidence for pronounced genome reduction was found. C. michiganensis subsp. michiganensis seems to have as many transporters and regulators as typical soil-inhabiting bacteria. However, the apparent lack of a sulfate reduction pathway, which makes C. michiganensis subsp. michiganensis dependent on reduced sulfur compounds for growth, is probably the reason for the poor survival of C. michiganensis subsp. michiganensis in soil. PMID:18192381

  3. Design and evaluation of specific PCR primers for rapid and reliable identification of Staphylococcus xylosus strains isolated from dry fermented sausages.

    PubMed

    Blaiotta, Giuseppe; Pennacchia, Carmelina; Parente, Eugenio; Villani, Francesco

    2003-11-01

    Rapid and reliable identification of Staphylococcus xylosus was achieved by species-specific PCR assays. Two sets of primers, targeting on xylulokinase (xylB) and 60 kDa heat-shock protein (hsp60) genes of S. xylosus, respectively, were designed. Species-specificity of both sets of primers was evaluated by using 27 reference strains of the DSM collection, representing 23 different species of the Staphylococcus genus and 3 species of the Kocuria genus. Moreover, 90 wild strains isolated from different fermented dry sausages were included in the analysis. By using primers xylB-F and xylB-R the expected PCR fragment was obtained only when DNA from S. xylosus was used. By contrast, amplification performed by using primers xylHs-F and xylHs-R produced a single PCR fragment, of the expected length, when DNA from S. xylosus, S. haemolyticus, S. intermedius and S. kloosii were used as template. Nevertheless, AluI digestion of the xylHs-F/xylHs-R PCR fragment allowed a clear differentiation of these 4 species. The rapidity (about 4 h from DNA isolation to results) and reliability of the PCR procedures established suggests that the method may be profitably applied for specific detection and identification of S. xylosus strains. PMID:14666989

  4. Natural Strain

    NASA Technical Reports Server (NTRS)

    Freed, Alan D.

    1997-01-01

    Logarithmic strain is the preferred measure of strain used by materials scientists, who typically refer to it as the "true strain." It was Nadai who gave it the name "natural strain," which seems more appropriate. This strain measure was proposed by Ludwik for the one-dimensional extension of a rod with length l. It was defined via the integral of dl/l to which Ludwik gave the name "effective specific strain." Today, it is after Hencky, who extended Ludwik's measure to three-dimensional analysis by defining logarithmic strains for the three principal directions.

  5. Geodermatophilus poikilotrophi sp. nov.: A Multitolerant Actinomycete Isolated from Dolomitic Marble

    PubMed Central

    Montero-Calasanz, Maria del Carmen; Hofner, Benjamin; Göker, Markus; Rohde, Manfred; Spröer, Cathrin; Hezbri, Karima; Gtari, Maher; Schumann, Peter; Klenk, Hans-Peter

    2014-01-01

    A novel Gram-reaction-positive, aerobic actinobacterium, tolerant to mitomycin C, heavy metals, metalloids, hydrogen peroxide, desiccation, and ionizing- and UV-radiation, designated G18T, was isolated from dolomitic marble collected from outcrops in Samara (Namibia). The growth range was 15–35°C, at pH 5.5–9.5 and in presence of 1% NaCl, forming greenish-black coloured colonies on GYM Streptomyces agar. Chemotaxonomic and molecular characteristics of the isolate matched those described for other representatives of the genus Geodermatophilus. The peptidoglycan contained meso-diaminopimelic acid as diagnostic diaminoacid. The main phospholipids were phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, and small amount of diphosphatidylglycerol. MK-9(H4) was the dominant menaquinone and galactose was detected as diagnostic sugar. The major cellular fatty acids were branched-chain saturated acids iso-C16:0 and iso-C15:0 and the unsaturated C17:1ω8c and C16:1ω7c. The 16S rRNA gene showed 97.4–99.1% sequence identity with the other representatives of genus Geodermatophilus. Based on phenotypic results and 16S rRNA gene sequence analysis, strain G18T is proposed to represent a novel species, Geodermatophilus poikilotrophi. Type strain is G18T (= DSM 44209T = CCUG 63018T). The INSDC accession number is HF970583. The novel R software package lethal was used to compute the lethal doses with confidence intervals resulting from tolerance experiments. PMID:25114928

  6. Geodermatophilus poikilotrophi sp. nov.: a multitolerant actinomycete isolated from dolomitic marble.

    PubMed

    del Carmen Montero-Calasanz, Maria; Hofner, Benjamin; Göker, Markus; Rohde, Manfred; Spröer, Cathrin; Hezbri, Karima; Gtari, Maher; Schumann, Peter; Klenk, Hans-Peter

    2014-01-01

    A novel Gram-reaction-positive, aerobic actinobacterium, tolerant to mitomycin C, heavy metals, metalloids, hydrogen peroxide, desiccation, and ionizing- and UV-radiation, designated G18T, was isolated from dolomitic marble collected from outcrops in Samara (Namibia). The growth range was 15-35°C, at pH 5.5-9.5 and in presence of 1% NaCl, forming greenish-black coloured colonies on GYM Streptomyces agar. Chemotaxonomic and molecular characteristics of the isolate matched those described for other representatives of the genus Geodermatophilus. The peptidoglycan contained meso-diaminopimelic acid as diagnostic diaminoacid. The main phospholipids were phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, and small amount of diphosphatidylglycerol. MK-9(H4) was the dominant menaquinone and galactose was detected as diagnostic sugar. The major cellular fatty acids were branched-chain saturated acids iso-C16:0 and iso-C15:0 and the unsaturated C17:1 ω8c and C16:1 ω7c. The 16S rRNA gene showed 97.4-99.1% sequence identity with the other representatives of genus Geodermatophilus. Based on phenotypic results and 16S rRNA gene sequence analysis, strain G18T is proposed to represent a novel species, Geodermatophilus poikilotrophi. Type strain is G18T (=DSM 44209T=CCUG 63018T). The INSDC accession number is HF970583. The novel R software package lethal was used to compute the lethal doses with confidence intervals resulting from tolerance experiments. PMID:25114928

  7. Non-radiative recombination in Ge1-ySny light emitting diodes: The role of strain relaxation in tuned heterostructure designs

    NASA Astrophysics Data System (ADS)

    Gallagher, J. D.; Senaratne, C. L.; Xu, C.; Sims, P.; Aoki, T.; Smith, D. J.; Menéndez, J.; Kouvetakis, J.

    2015-06-01

    This paper describes the properties of Ge1-ySny light emitting diodes with a broad range of Sn concentrations (y = 0.0-0.11). The devices are grown upon Si(100) platforms using ultra-low temperature deposition of highly reactive Ge and Sn hydrides. The device fabrication adopts two new photodiode designs which lead to optimized performance and enables a systematic study of the effects of strain relaxation on emission efficiency. In contrast with n-Ge/i-Ge1-ySny/p-Ge analogs, which in most cases contain two defected interfaces, our designs include a p-layer with composition Ge1-zSnz chosen to be z < y to facilitate light extraction, but with z close enough to y to guarantee no strain relaxation at the i/p interface. In addition, a Ge1-xSnx alloy is also used for the n layer, with compositions in the 0 ≤ x ≤ y range, so that defected and non-defected n/i interfaces can be studied. The electroluminescence spectra vs the Sn content y in the intrinsic layer of the diodes exhibit a monotonic shift in the emission wavelength from 1550 nm to 2500 nm. On the other hand, the emission intensities show a complex dependence that cannot be explained solely on the basis of Sn concentrations. Detailed theoretical modeling of these intensities makes it possible to extract recombination lifetimes that are found to be more than three times longer in samples in which strain relaxation has not occurred at the n-i interface, demonstrating the existence of a large non-radiative contribution from the relaxation defects. This finding is particularly significant for direct gap diodes with y > 0.09, for which it is practically impossible to avoid strain relaxation in n-Ge/i-Ge1-ySny/p-Ge analogs. The new designs introduced here open the door to the fabrication of highly efficient electrically pumped systems for applications in future generations of integrated photonics.

  8. Non-radiative recombination in Ge{sub 1−y}Sn{sub y} light emitting diodes: The role of strain relaxation in tuned heterostructure designs

    SciTech Connect

    Gallagher, J. D.; Xu, C.; Smith, D. J.; Menéndez, J.; Senaratne, C. L.; Sims, P.; Kouvetakis, J.; Aoki, T.

    2015-06-28

    This paper describes the properties of Ge{sub 1−y}Sn{sub y} light emitting diodes with a broad range of Sn concentrations (y = 0.0–0.11). The devices are grown upon Si(100) platforms using ultra-low temperature deposition of highly reactive Ge and Sn hydrides. The device fabrication adopts two new photodiode designs which lead to optimized performance and enables a systematic study of the effects of strain relaxation on emission efficiency. In contrast with n-Ge/i-Ge{sub 1−y}Sn{sub y}/p-Ge analogs, which in most cases contain two defected interfaces, our designs include a p-layer with composition Ge{sub 1−z}Sn{sub z} chosen to be z < y to facilitate light extraction, but with z close enough to y to guarantee no strain relaxation at the i/p interface. In addition, a Ge{sub 1−x}Sn{sub x} alloy is also used for the n layer, with compositions in the 0 ≤ x ≤ y range, so that defected and non-defected n/i interfaces can be studied. The electroluminescence spectra vs the Sn content y in the intrinsic layer of the diodes exhibit a monotonic shift in the emission wavelength from 1550 nm to 2500 nm. On the other hand, the emission intensities show a complex dependence that cannot be explained solely on the basis of Sn concentrations. Detailed theoretical modeling of these intensities makes it possible to extract recombination lifetimes that are found to be more than three times longer in samples in which strain relaxation has not occurred at the n-i interface, demonstrating the existence of a large non-radiative contribution from the relaxation defects. This finding is particularly significant for direct gap diodes with y > 0.09, for which it is practically impossible to avoid strain relaxation in n-Ge/i-Ge{sub 1−y}Sn{sub y}/p-Ge analogs. The new designs introduced here open the door to the fabrication of highly efficient electrically pumped systems for applications in future generations of integrated photonics.

  9. Different Physiological Roles of ATP- and PPi-Dependent Phosphofructokinase Isoenzymes in the Methylotrophic Actinomycete Amycolatopsis methanolica

    PubMed Central

    Alves, A. M. C. R.; Euverink, G. J. W.; Santos, H.; Dijkhuizen, L.

    2001-01-01

    Cells of the actinomycete Amycolatopsis methanolica grown on glucose possess only a single, exclusively PPi-dependent phosphofructokinase (PPi-PFK) (A. M. C. R. Alves, G. J. W. Euverink, H. J. Hektor, J. van der Vlag, W. Vrijbloed, D.H.A. Hondmann, J. Visser, and L. Dijkhuizen, J. Bacteriol. 176:6827–6835, 1994). When this methylotrophic bacterium is grown on one-carbon (C1) compounds (e.g., methanol), an ATP-dependent phosphofructokinase (ATP-PFK) activity is specifically induced, completely replacing the PPi-PFK. The two A. methanolica PFK isoenzymes have very distinct functions, namely, in the metabolism of C6 and C1 carbon substrates. This is the first report providing biochemical evidence for the presence and physiological roles of PPi-PFK and ATP-PFK isoenzymes in a bacterium. The novel ATP-PFK enzyme was purified to homogeneity and characterized in detail at the biochemical and molecular levels. The A. methanolica ATP-PFK and PPi-PFK proteins possess a low level of amino acid sequence similarity (24%), clearly showing that the two proteins are not the result of a gene duplication event. PPi-PFK is closely related to other (putative) actinomycete PFK enzymes. Surprisingly, the A. methanolica ATP-PFK is most similar to ATP-PFK from the protozoon Trypanosoma brucei and PPi-PFK proteins from the bacteria Borrelia burgdorferi and Treponema pallidum, both spirochetes, very distinct from actinomycetes. The data thus suggest that A. methanolica obtained the ATP-PFK-encoding gene via a lateral gene transfer event. PMID:11717283

  10. Diketopiperazine Derivatives from the Marine-Derived Actinomycete Streptomyces sp. FXJ7.328

    PubMed Central

    Wang, Pei; Xi, Lijun; Liu, Peipei; Wang, Yi; Wang, Wei; Huang, Ying; Zhu, Weiming

    2013-01-01

    Five new diketopiperazine derivatives, (3Z,6E)-1-N-methyl-3-benzylidene-6-(2S-methyl-3-hydroxypropylidene)piperazine-2,5-dione (1), (3Z,6E)-1-N-methyl-3-benzylidene-6-(2R-methyl-3-hydroxypropylidene)piperazine-2,5-dione (2), (3Z,6Z)-3-(4-hydroxybenzylidene)-6-isobutylidenepiperazine-2,5-dione (3), (3Z,6Z)-3-((1H-imidazol-5-yl)-methylene)-6-isobutylidenepiperazine-2,5-dione (4), and (3Z,6S)-3-benzylidene-6-(2S-but-2-yl)piperazine-2,5-dione (5), were isolated from the marine-derived actinomycete Streptomyces sp. FXJ7.328. The structures of 1–5 were determined by spectroscopic analysis, CD exciton chirality, the modified Mosher’s, Marfey’s and the C3 Marfey’s methods. Compound 3 showed modest antivirus activity against influenza A (H1N1) virus with an IC50 value of 41.5 ± 4.5 μM. In addition, compound 6 and 7 displayed potent anti-H1N1 activity with IC50 value of 28.9 ± 2.2 and 6.8 ± 1.5 μM, respectively. Due to the lack of corresponding data in the literature, the 13C NMR data of (3Z,6S)-3-benzylidene-6-isobutylpiperazine-2,5-dione (6) were also reported here for the first time. PMID:23538868

  11. Thermodynamics of a Ca(2+)-dependent highly thermostable alkaline protease from a haloalkliphilic actinomycete.

    PubMed

    Gohel, S D; Singh, S P

    2015-01-01

    An alkaline protease from salt-tolerant alkaliphilic actinomycetes, Nocardiopsis alba OK-5 was purified by a single-step hydrophobic interaction chromatography and characterized. The purified protease with an estimated molecular mass of 20 kDa was optimally active at 70 °C in 0-3 M NaCl and 0-100 mM Ca(2+) displaying significant stability at 50-80 °C. The enzyme was stable at 80 °C in 100 mM Ca(2+) with Kd of 17 × 10(-3) and t1/2 of 32 min. The activation energy (Ea), enthalpy (ΔH*), and entropy (ΔS*) for the protease deactivation calculated in the presence of 200 mM Ca(2+) were 38.15 kJ/mol, 35.49 kJ/mol and 183.48 J/mol, respectively. The change in free energy (ΔG*) for protease deactivation at 60 °C in 200 mM Ca(2+) was 95.88 kJ/mol. Decrease in ΔH* reflected reduced cooperativity of deactivation and unfolding. The enzyme was intrinsically stable that counteracted heat denaturation by a weak cooperativity during the unfolding. Further, the enzyme was highly stable in the presence of various cations, surfactants, H2O2, β-mercaptoethanol, and commercial detergents. The compatibility of the enzyme with various cations, surfactants, and detergent matrices suggests its suitability as an additive in the detergents and peptide synthesis. PMID:25150113

  12. Characterization of a Rifampin-Inactivating Glycosyltransferase from a Screen of Environmental Actinomycetes

    PubMed Central

    Spanogiannopoulos, Peter; Thaker, Maulik; Koteva, Kalinka; Waglechner, Nicholas

    2012-01-01

    Identifying and understanding the collection of all antibiotic resistance determinants presented in the global microbiota, the antibiotic resistome, provides insight into the evolution of antibiotic resistance and critical information for the development of future antimicrobials. The rifamycins are broad-spectrum antibiotics that target bacterial transcription by inhibition of RNA polymerase. Although mutational alteration of the drug target is the predominant mechanism of resistance to this family of antibiotics in the clinic, a number of diverse inactivation mechanisms have also been reported. In this report, we investigate a subset of environmental rifampin-resistant actinomycete isolates and identify a diverse collection of rifampin inactivation mechanisms. We describe a single isolate, WAC1438, capable of inactivating rifampin by glycosylation. A draft genome sequence of WAC1438 (most closely related to Streptomyces speibonae, according to a 16S rRNA gene comparison) was assembled, and the associated rifampin glycosyltransferase open reading frame, rgt1438, was identified. The role of rgt1438 in rifampin resistance was confirmed by its disruption in the bacterial chromosome, resulting in a loss of antibiotic inactivation and a 4-fold decrease in MIC. Interestingly, examination of the RNA polymerase β-subunit sequence of WAC1438 suggests that it harbors a resistant target and thus possesses dual mechanisms of rifamycin resistance. Using an in vitro assay with purified enzyme, Rgt1438 could inactivate a variety of rifamycin antibiotics with comparable steady-state kinetics constants. Our results identify rgt1438 as a rifampin resistance determinant from WAC1438 capable of inactivating an assortment of rifamycins, adding a new element to the rifampin resistome. PMID:22802246

  13. Use of dyes in solid medium for screening ligninolytic activity of selective actinomycetes

    SciTech Connect

    Chahal, D.S.; Kluepfel, D.; Morosoli, R.

    1995-12-31

    Lignin, a three-dimensional biopolymer, not only encrusts the cellulose microfibrils in a sheath-like manner, but is also bonded physically and chemically to the plant polysaccharides. Unless the lignin is depolymerized, solubilized, or removed, the cellulose and hemicelluloses cannot be easily hydrolyzed by respective enzymes for their bioconversion into biofuels and chemicals. By now it has been established that lignin peroxidase (LiP) of white-rot fungus Phanerochaete chrysosporium is responsible for degradation of lignin. It has been reported that LiP is produced during secondary metabolism under carbon or nitrogen limitation by this organism. In literature, usually low yields (per unit volume) of LiP with P. chrysosporium have been reported. The reasons for low yields may be attributed to insufficient nitrogen in production media, which ultimately affects the synthesis of LiP protein. Therefore, it necessitated a search for an organism that can produce a ligninolytic enzyme system during its primary metabolism, without any effect of nitrogen limitation in the fermentation medium and without supply of extra oxygen to the cultures. Glenn and Gold were the first to report that decolorization of polymeric dyes in liquid cultures is related to the lignin degradation system. They demonstrated that like lignin degradation, the decolorization of polymeric dyes by the white-rot basidiomycete P. chrysosporium occurred during secondary metabolism, was suppressed in cultures grown in the presence of high levels of nitrogen, and was strongly dependent on the oxygen concentration in the cultures. The present study was undertaken to establish if certain dyes in solid media could be used to screen ligninolytic activity of selective actinomycetes during their primary metabolism without the limitation of nitrogen in the medium.

  14. Design and Development of a Flexible Strain Sensor for Textile Structures Based on a Conductive Polymer Composite

    PubMed Central

    Cochrane, Cédric; Koncar, Vladan; Lewandowski, Maryline; Dufour, Claude

    2007-01-01

    The aim of this work is to develop a smart flexible sensor adapted to textile structures, able to measure their strain deformations. The sensors are “smart” because of their capacity to adapt to the specific mechanical properties of textile structures that are lightweight, highly flexible, stretchable, elastic, etc. Because of these properties, textile structures are continuously in movement and easily deformed, even under very low stresses. It is therefore important that the integration of a sensor does not modify their general behavior. The material used for the sensor is based on a thermoplastic elastomer (Evoprene)/carbon black nanoparticle composite, and presents general mechanical properties strongly compatible with the textile substrate. Two preparation techniques are investigated: the conventional melt-mixing process, and the solvent process which is found to be more adapted for this particular application. The preparation procedure is fully described, namely the optimization of the process in terms of filler concentration in which the percolation theory aspects have to be considered. The sensor is then integrated on a thin, lightweight Nylon fabric, and the electromechanical characterization is performed to demonstrate the adaptability and the correct functioning of the sensor as a strain gauge on the fabric. A normalized relative resistance is defined in order to characterize the electrical response of the sensor. Finally, the influence of environmental factors, such as temperature and atmospheric humidity, on the sensor performance is investigated. The results show that the sensor's electrical resistance is particularly affected by humidity. This behavior is discussed in terms of the sensitivity of the carbon black filler particles to the presence of water.

  15. Changes in Actinomycetes community structure under the influence of Bt transgenic brinjal crop in a tropical agroecosystem

    PubMed Central

    2013-01-01

    Background The global area under brinjal cultivation is expected to be 1.85 million hectare with total fruit production about 32 million metric tons (MTs). Brinjal cultivars are susceptible to a variety of stresses that significantly limit productivity. The most important biotic stress is caused by the Brinjal fruit and shoot Borer (FSB) forcing farmers to deploy high doses of insecticides; a matter of serious health concern. Therefore, to control the adverse effect of insecticides on the environment including the soil, transgenic technology has emerged as the effective alternative. However, the reports, regarding the nature of interaction of transgenic crops with the native microbial community are inconsistent. The effect of a Bt transgenic brinjal expressing the bio-insecticidal protein (Cry1Ac) on the rhizospheric community of actinomycetes has been assessed and compared with its non-transgenic counterpart. Results Significant variation in the organic carbon observed between the crops (non-Bt and Bt brinjal) may be due to changes in root exudates quality and composition mediated by genetic attributes of Bt transgenic brinjal. Real time quantitative PCR indicated significant differences in the actinomycetes- specific 16S rRNA gene copy numbers between the non-Bt (5.62-27.86) × 1011 g-1 dws and Bt brinjal planted soil (5.62-24.04) × 1011 g-1 dws. Phylogenetic analysis indicated 14 and 11, actinomycetes related groups in soil with non-Bt and Bt brinjal crop, respectively. Micrococaceaea and Nocardiodaceae were the dominant groups in pre-vegetation, branching, flowering, maturation and post-harvest stage. However, Promicromonosporaceae, Streptosporangiaceae, Mycobacteriaceae, Geodermatophilaceae, Frankiaceae, Kineosporaceae, Actisymmetaceae and Streptomycetaceae were exclusively detected in a few stages in non-Bt brinjal rhizosphere soil while Nakamurellaceae, Corynebactericeae, Thermomonosporaceae and Pseudonocardiaceae in Bt brinjal counterpart

  16. Spoxazomicins A-C, novel antitrypanosomal alkaloids produced by an endophytic actinomycete, Streptosporangium oxazolinicum K07-0460(T).

    PubMed

    Inahashi, Yuki; Iwatsuki, Masato; Ishiyama, Aki; Namatame, Miyuki; Nishihara-Tsukashima, Aki; Matsumoto, Atsuko; Hirose, Tomoyasu; Sunazuka, Toshiaki; Yamada, Haruki; Otoguro, Kazuhiko; Takahashi, Yōko; Omura, Satoshi; Shiomi, Kazuro

    2011-04-01

    Three novel antitrypanosomal alkaloids, named spoxazomicins A-C, were isolated by silica gel column chromatography and HPLC from the culture broth of a new endophytic actinomycete species, Streptosporangium oxazolinicum K07-0460(T). The structures of the spoxazomicins were elucidated by NMR and X-ray crystal analyses and shown to be new types of pyochelin family antibiotic. Spoxazomicin A showed potent and selective antitrypanosomal activity with an IC₅₀ value of 0.11 μg ml⁻¹ in vitro without cytotoxicity against MRC-5 cells (IC₅₀=27.8 μg ml⁻¹). PMID:21386848

  17. Cephamycins, a new family of beta-lactam antibiotics. I. Production by actinomycetes, including Streptomyces lactamdurans sp. n.

    PubMed

    Stapley, E O; Jackson, M; Hernandez, S; Zimmerman, S B; Currie, S A; Mochales, S; Mata, J M; Woodruff, H B; Hendlin, D

    1972-09-01

    A number of actinomycetes isolated from soil were found to produce one or more members of a new family of antibiotics, the cephamycins, which are structurally related to cephalosporin C. The cephamycins were produced in submerged fermentation in a wide variety of media by one or more of eight different species of Streptomyces, including a newly described species, S. lactamdurans. These antibiotics exhibit antibacterial activity against a broad spectrum of bacteria which includes many that are resistant to the cephalosporins and penicillins. PMID:4790552

  18. Sprains and Strains

    MedlinePlus

    ... people at risk for strains. Gymnastics, tennis, rowing, golf, and other sports that require extensive gripping can ... Trials and You was designed to help people learn more about clinical trials, why they matter, and ...

  19. Complete genome sequence of Kibdelosporangium phytohabitans KLBMP 1111(T), a plant growth promoting endophytic actinomycete isolated from oil-seed plant Jatropha curcas L.

    PubMed

    Qin, Sheng; Feng, Wei-Wei; Xing, Ke; Bai, Juan-Luan; Yuan, Bo; Liu, Wei-Jie; Jiang, Ji-Hong

    2015-12-20

    Kibdelosporangium phytohabitans KLBMP 1111(T) is a plant growth promoting endophytic actinomycete isolated from the oil-seed plant Jatropha curcas L. collected from dry-hot valley, in Sichuan, China. The complete genome sequence of this actinomycete consists of one chromosome (11,759,770bp) with no plasmid. From the genome, we identified gene clusters responsible for polyketide and nonribosomal peptide synthesis of natural products, and genes related to the plant growth promoting, such as zeatin, 1-aminocyclopropane-1-carboxylate deaminase (ACCD) and siderophore. The complete genome information may be useful to understand the beneficial interactions between K. phytohabitans KLBMP 1111(T) and host plants. PMID:26516119

  20. New antibiotics SF2315A and B produced by an Excellospora sp. I. Taxonomy of the strain, isolation and characterization of antibiotics.

    PubMed

    Sasaki, T; Yoshida, J; Itoh, M; Gomi, S; Shomura, T; Sezaki, M

    1988-07-01

    Two new antibiotics SF2315A and B have been isolated from culture filtrate of an actinomycete strain, Excellospora viridilutea SF2315. They are weakly active against Gram-positive bacteria and inhibited reverse transcriptase of avian myeloblastosis virus. Empirical molecular formula of antibiotics SF2315A and B were determined to be C19H16O5 and C19H20O6, respectively. PMID:3417555

  1. Natural Strain

    NASA Technical Reports Server (NTRS)

    Freed, Alan D.

    1995-01-01

    The purpose of this paper is to present a consistent and thorough development of the strain and strain-rate measures affiliated with Hencky. Natural measures for strain and strain-rate, as I refer to them, are first expressed in terms of of the fundamental body-metric tensors of Lodge. These strain and strain-rate measures are mixed tensor fields. They are mapped from the body to space in both the Eulerian and Lagrangian configurations, and then transformed from general to Cartesian fields. There they are compared with the various strain and strain-rate measures found in the literature. A simple Cartesian description for Hencky strain-rate in the Lagrangian state is obtained.

  2. Screening of Rhizospheric Actinomycetes for Various In-vitro and In-vivo Plant Growth Promoting (PGP) Traits and for Agroactive Compounds

    PubMed Central

    Anwar, Sumaira; Ali, Basharat; Sajid, Imran

    2016-01-01

    In this study 98 rhizospheric actinomycetes were isolated from different wheat and tomato fields, Punjab, Pakistan. The isolates were characterized morphologically, biochemically, and genetically and were subjected to a comprehensive in vitro screening for various plant growth promoting (PGP) traits. About 30% of the isolates screened were found to be the promising PGP rhizobacteria (PGPRs), which exhibited maximum genetic similarity (up to 98–99%) with different species of the genus Streptomyces by using16S rRNA gene sequencing. The most active indole acetic acid (IAA) producer Streptomyces nobilis WA-3, Streptomyces Kunmingenesis WC-3, and Streptomyces enissocaesilis TA-3 produce 79.5, 79.23, and 69.26 μg/ml IAA respectively at 500 μg/ml L-tryptophan. The highest concentration of soluble phosphate was produced by Streptomyces sp. WA-1 (72.13 mg/100 ml) and S. djakartensis TB-4 (70.36 mg/100 ml). All rhizobacterial isolates were positive for siderophore, ammonia, and hydrogen cyanide production. Strain S. mutabilis WD-3 showed highest concentration of ACC-deaminase (1.9 mmol /l). For in-vivo screening, seed germination, and plant growth experiment were conducted by inoculating wheat (Triticum aestivum) seeds with the six selected isolates. Significant increases in shoot length was observed with S. nobilis WA-3 (65%), increased root length was recorded in case of S. nobilis WA-3 (81%) as compared to water treated control plants. Maximum increases in plant fresh weight were recorded with S. nobilis WA-3 (84%), increased plant dry weight was recorded in case of S. nobilis WA-3 (85%) as compared to water treated control plants. In case of number of leaves, significant increase was recorded with S. nobilis WA-3 (27%) and significant increase in case of number of roots were recorded in case of strain S. nobilis WA-3 (30%) as compared to control plants. Over all the study revealed that these rhizospheric PGP Streptomyces are good candidates to be developed as

  3. Screening of Rhizospheric Actinomycetes for Various In-vitro and In-vivo Plant Growth Promoting (PGP) Traits and for Agroactive Compounds.

    PubMed

    Anwar, Sumaira; Ali, Basharat; Sajid, Imran

    2016-01-01

    In this study 98 rhizospheric actinomycetes were isolated from different wheat and tomato fields, Punjab, Pakistan. The isolates were characterized morphologically, biochemically, and genetically and were subjected to a comprehensive in vitro screening for various plant growth promoting (PGP) traits. About 30% of the isolates screened were found to be the promising PGP rhizobacteria (PGPRs), which exhibited maximum genetic similarity (up to 98-99%) with different species of the genus Streptomyces by using16S rRNA gene sequencing. The most active indole acetic acid (IAA) producer Streptomyces nobilis WA-3, Streptomyces Kunmingenesis WC-3, and Streptomyces enissocaesilis TA-3 produce 79.5, 79.23, and 69.26 μg/ml IAA respectively at 500 μg/ml L-tryptophan. The highest concentration of soluble phosphate was produced by Streptomyces sp. WA-1 (72.13 mg/100 ml) and S. djakartensis TB-4 (70.36 mg/100 ml). All rhizobacterial isolates were positive for siderophore, ammonia, and hydrogen cyanide production. Strain S. mutabilis WD-3 showed highest concentration of ACC-deaminase (1.9 mmol /l). For in-vivo screening, seed germination, and plant growth experiment were conducted by inoculating wheat (Triticum aestivum) seeds with the six selected isolates. Significant increases in shoot length was observed with S. nobilis WA-3 (65%), increased root length was recorded in case of S. nobilis WA-3 (81%) as compared to water treated control plants. Maximum increases in plant fresh weight were recorded with S. nobilis WA-3 (84%), increased plant dry weight was recorded in case of S. nobilis WA-3 (85%) as compared to water treated control plants. In case of number of leaves, significant increase was recorded with S. nobilis WA-3 (27%) and significant increase in case of number of roots were recorded in case of strain S. nobilis WA-3 (30%) as compared to control plants. Over all the study revealed that these rhizospheric PGP Streptomyces are good candidates to be developed as

  4. Novel optical system for in vitro quantification of full surface strain fields in small arteries: I. Theory and design.

    PubMed

    Genovese, K; Lee, Y U; Humphrey, J D

    2011-03-01

    Recent advances in vascular biology and pathophysiology have revealed the need to understand better the genetic basis of arterial stiffness, disease progression and responses to clinical intervention. Towards this end, in vitro experiments on arteries from genetically modified mice promise to provide significantly increased insight into both health and disease. The need to test small arteries, often of complex shape, necessitates new methods for experimental arterial mechanics, however, ones that can provide information on local changes in geometry and strain. In this paper, we present a theoretical framework for a new panoramic digital image correlation-based method sufficient to collect such information and we demonstrate the utility of this approach via validation studies on phantoms having dimensions on the order of 500-1000 μm, similar to those of large mouse arteries. In particular, we show that placing the specimen within a conical mirror and imaging the specimen via a gimbal-mounted mirror using a single camera yields stereo information sufficient to quantify the size, shape and deformation along the full length and around the entire circumference of small arteries. In a companion paper, we show further that this approach can be implemented effectively while testing arteries within a physiological solution that maintains native biomechanical properties. PMID:21347912

  5. Development of a Custom-Designed, Pan Genomic DNA Microarray to Characterize Strain-Level Diversity among Cronobacter spp.

    PubMed Central

    Tall, Ben Davies; Gangiredla, Jayanthi; Gopinath, Gopal R.; Yan, Qiongqiong; Chase, Hannah R.; Lee, Boram; Hwang, Seongeun; Trach, Larisa; Park, Eunbi; Yoo, YeonJoo; Chung, TaeJung; Jackson, Scott A.; Patel, Isha R.; Sathyamoorthy, Venugopal; Pava-Ripoll, Monica; Kotewicz, Michael L.; Carter, Laurenda; Iversen, Carol; Pagotto, Franco; Stephan, Roger; Lehner, Angelika; Fanning, Séamus; Grim, Christopher J.

    2015-01-01

    Cronobacter species cause infections in all age groups; however neonates are at highest risk and remain the most susceptible age group for life-threatening invasive disease. The genus contains seven species:Cronobacter sakazakii, Cronobacter malonaticus, Cronobacter turicensis, Cronobacter muytjensii, Cronobacter dublinensis, Cronobacter universalis, and Cronobacter condimenti. Despite an abundance of published genomes of these species, genomics-based epidemiology of the genus is not well established. The gene content of a diverse group of 126 unique Cronobacter and taxonomically related isolates was determined using a pan genomic-based DNA microarray as a genotyping tool and as a means to identify outbreak isolates for food safety, environmental, and clinical surveillance purposes. The microarray constitutes 19,287 independent genes representing 15 Cronobacter genomes and 18 plasmids and 2,371 virulence factor genes of phylogenetically related Gram-negative bacteria. The Cronobacter microarray was able to distinguish the seven Cronobacter species from one another and from non-Cronobacter species; and within each species, strains grouped into distinct clusters based on their genomic diversity. These results also support the phylogenic divergence of the genus and clearly highlight the genomic diversity among each member of the genus. The current study establishes a powerful platform for further genomics research of this diverse genus, an important prerequisite toward the development of future countermeasures against this foodborne pathogen in the food safety and clinical arenas. PMID:25984509

  6. Immunologic relatedness of extracellular ligninases from the actinomycetes Streptomyces viridosporus T7A and Streptomyces badius 252

    SciTech Connect

    Magnuson, T.S.; Roberts, M.A.; Crawford, D.L.; Hertel, G.

    1991-12-31

    Four isoforms of the extracellular lignin peroxidase of the ligninolytic actinomycete Streptomyces viridosporus T7A (ALip-P1, P2, P3, and P4) were individually purified by ultrafiltration and ammonium sulfate precipitation, followed by electro-elution using polyacrylamide gel electrophoresis. Three of the purified peroxidases were compared for their immunologic relatedness by Western blot analysis using a polyclonal antibody preparation produced in rabbits against pure isoform P3. The anti-P3 antibody was also tested for its reactivity towards a lignin peroxidase from the white-rot fungus Phanerochaete chrysosporium and another ligninolytic actinomycete Streptomyces badius 252. Results showed that peroxidases ALip-P1 through ALip-P3 are immunologically related to one another. The peroxidases of S. badius, but not the peroxidase of P. chrysosporium, also reacted with the antibody, thus indicating that the lignin peroxidases of S. viridosporus and S. badius are immunologically related. Based upon its specific affinity, fignin peroxidase isoform ALip-P3 of S. viridosporus was readily purified using an anti-P3 antibody affinity column.

  7. A Method for Calculating Strain Energy Release Rates in Preliminary Design of Composite Skin/Stringer Debonding Under Multi-Axial Loading

    NASA Technical Reports Server (NTRS)

    Krueger, Ronald; Minguet, Pierre J.; OBrien, T. Kevin

    1999-01-01

    Three simple procedures were developed to determine strain energy release rates, G, in composite skin/stringer specimens for various combinations of unaxial and biaxial (in-plane/out-of-plane) loading conditions. These procedures may be used for parametric design studies in such a way that only a few finite element computations will be necessary for a study of many load combinations. The results were compared with mixed mode strain energy release rates calculated directly from nonlinear two-dimensional plane-strain finite element analyses using the virtual crack closure technique. The first procedure involved solving three unknown parameters needed to determine the energy release rates. Good agreement was obtained when the external loads were used in the expression derived. This superposition technique was only applicable if the structure exhibits a linear load/deflection behavior. Consequently, a second technique was derived which was applicable in the case of nonlinear load/deformation behavior. The technique involved calculating six unknown parameters from a set of six simultaneous linear equations with data from six nonlinear analyses to determine the energy release rates. This procedure was not time efficient, and hence, less appealing. A third procedure was developed to calculate mixed mode energy release rates as a function of delamination lengths. This procedure required only one nonlinear finite element analysis of the specimen with a single delamination length to obtain a reference solution for the energy release rates and the scale factors. The delamination was extended in three separate linear models of the local area in the vicinity of the delamination subjected to unit loads to obtain the distribution of G with delamination lengths. This set of sub-problems was Although additional modeling effort is required to create the sub- models, this local technique is efficient for parametric studies.

  8. Morphological, physiological, and molecular characterization of actinomycetes isolated from dry soil, rocks, and monument surfaces.

    PubMed

    Eppard, M; Krumbein, W E; Koch, C; Rhiel, E; Staley, J T; Stackebrandt, E

    1996-07-01

    In an extended study on the biodiversity of rock-dwelling bacteria, the colony and cell morphology, physiology, protein patterns, and 16S rDNA sequences of 17 bacterial strains isolated from different surfaces of rocks, stones, and monuments and from various geographical locations were characterized. All except one strain, which was found to be a Bacillus, were members of the order Actinomycetales. The majority of the strains either were closely related to Geodermatophilus obscurus, which was also analyzed in this study, or formed a closely related sister taxon. All of these strains were isolated from the surface of marble in Namibia and Greece and from limestone from the Negev desert, Israel. One strain, G10, of Namibia origin was equidistantly related to Geodermatophilus obscurus, Frankia alni, Sporichthya polymorpha, and Acidothermus cellulolyticus. Three strains from rock varnish in the Mojave desert, California, were found to be highly related to Arthrobacter (formerly Micrococcus) agilis. All clusters could be confirmed from results of studies on morphological and physiological properties and from banding patterns of whole cell proteins. Based on the results of tests, four additional strains were assigned to the lineage defined by strain G10. PMID:8661940

  9. Large-strain, multiform movements from designable electrothermal actuators based on large highly anisotropic carbon nanotube sheets.

    PubMed

    Li, Qingwei; Liu, Changhong; Lin, Yuan-Hua; Liu, Liang; Jiang, Kaili; Fan, Shoushan

    2015-01-27

    Many electroactive polymer (EAP) actuators use diverse configurations of carbon nanotubes (CNTs) as pliable electrodes to realize discontinuous, agile movements, for CNTs are conductive and flexible. However, the reported CNT-based EAP actuators could only accomplish simple, monotonous actions. Few actuators were extended to complex devices because efficiently preparing a large-area CNT electrode was difficult, and complex electrode design has not been carried out. In this work, we successfully prepared large-area CNT paper (buckypaper, BP) through an efficient approach. The BP is highly anisotropic, strong, and suitable as flexible electrodes. By means of artful graphic design and processing on BP, we fabricated various functional BP electrodes and developed a series of BP-polymer electrothermal actuators (ETAs). The prepared ETAs can realize various controllable movements, such as large-stain bending (>180°), helical curling (∼ 630°), or even bionic actuations (imitating human-hand actions). These functional and interesting movements benefit from flexible electrode design and the anisotropy of BP material. Owing to the advantages of low driving voltage (20-200 V), electrolyte-free and long service life (over 10000 times), we think the ETAs will have great potential applications in the actuator field. PMID:25559661

  10. Optical properties of InAsBi and optimal designs of lattice-matched and strain-balanced III-V semiconductor superlattices

    NASA Astrophysics Data System (ADS)

    Webster, P. T.; Shalindar, A. J.; Riordan, N. A.; Gogineni, C.; Liang, H.; Sharma, A. R.; Johnson, S. R.

    2016-06-01

    The optical properties of bulk InAs0.936Bi0.064 grown by molecular beam epitaxy on a (100)-oriented GaSb substrate are measured using spectroscopic ellipsometry. The index of refraction and absorption coefficient are measured over photon energies ranging from 44 meV to 4.4 eV and are used to identify the room temperature bandgap energy of bulk InAs0.936Bi0.064 as 60.6 meV. The bandgap of InAsBi is expressed as a function of Bi mole fraction using the band anticrossing model and a characteristic coupling strength of 1.529 eV between the Bi impurity state and the InAs valence band. These results are programmed into a software tool that calculates the miniband structure of semiconductor superlattices and identifies optimal designs in terms of maximizing the electron-hole wavefunction overlap as a function of transition energy. These functionalities are demonstrated by mapping the design spaces of lattice-matched GaSb/InAs0.911Sb0.089 and GaSb/InAs0.932Bi0.068 and strain-balanced InAs/InAsSb, InAs/GaInSb, and InAs/InAsBi superlattices on GaSb. The absorption properties of each of these material systems are directly compared by relating the wavefunction overlap square to the absorption coefficient of each optimized design. Optimal design criteria are provided for key detector wavelengths for each superlattice system. The optimal design mid-wave infrared InAs/InAsSb superlattice is grown using molecular beam epitaxy, and its optical properties are evaluated using spectroscopic ellipsometry and photoluminescence spectroscopy.

  11. New Source Heterojunction Structures with Relaxed/Strained Semiconductors for Quasi-Ballistic Complementary Metal-Oxide-Semiconductor Transistors: Relaxation Technique of Strained Substrates and Design of Sub-10 nm Devices

    NASA Astrophysics Data System (ADS)

    Tomohisa Mizuno,; Naoki Mizoguchi,; Kotaro Tanimoto,; Tomoaki Yamauchi,; Mitsuo Hasegawa,; Toshiyuki Sameshima,; Tsutomu Tezuka,

    2010-04-01

    We have studied new abrupt-source-relaxed/strained semiconductor-heterojunction structures for quasi-ballistic complementary metal-oxide-semiconductor (CMOS) devices, by locally controlling the strain of a single strained semiconductor. Appling O+ ion implantation recoil energy to the strained semiconductor/buried oxide interface, Raman analysis of the strained layers indicates that we have successfully relaxed both strained-Si-on-insulator (SSOI) substrates for n-MOS and SiGe-on-insulator (SGOI) substrates for p-MOS without polycrystallizing the semiconductor layers, by optimizing O+ ion implantation conditions. As a result, it is considered that the source conduction and valence band offsets Δ EC and Δ EV can be realized by the energy difference in the source Si/channel-strained Si and the source-relaxed SiGe/channel-strained SiGe layers, respectively. The device simulator, considering the tunneling effects at the source heterojunction, shows that the transconductance of sub-10 nm source heterojunction MOS transistors (SHOT) continues to increase with increasing Δ EC. Therefore, SHOT structures with the novel source heterojunction are very promising for future quasi-ballistic CMOS devices.

  12. Modelling, Design, Growth and Characterization of Strain Balanced Quantum Cascade Lasers (3-11mum), grown by Gas Source Molecular Beam Epitaxy

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, Neelanjan

    Quantum Cascade Laser (QCL) is a compact room temperature (RT) source of mid-infrared radiation, which can be used for spectroscopic detection of trace amount of chemicals. The mid-infrared spectral range between (3-11 microm), has a dense array of absorption lines of numerous molecules, due to the presence of fundamental vibrational modes. The goal of this thesis can be subdivided into two parts. Firstly, short wavelength QCLs, emitting below 4microm, perform poorly at RT, due to inter-valley Gamma --- L carrier scattering, carrier escape to the continuum, heat removal from the core region at high power density corresponding to short wavelength operation, and large interface scattering due to highly strained materials. Secondly, it is desirable to have a single QCL based source emitting between 6-10microm, which be used to detect multiple molecules having their peak absorptions far apart, inside this spectral range. However, gain bandwidth of a single core QCL is relatively small, so laser emission cannot be tuned over a wide spectral range. This thesis describes the working principle of a QCL based on superlattice transport, rate equations, scattering mechanism, and waveguide design. The choice of the material system for this work and the fundamentals of band structure engineering has been derived. Gas source molecular beam epitaxy - growth optimization and characterization is one of the most important features of this work, especially for short wavelength QCLs, and has been explained in depth. Different strategies for design of active region design of short wavelength QCL and heterogeneous broadband QCL has been explored. The major milestones, of this research was the world's first watt level continuous wave (CW), RT demonstration at 3.76 microm, which was followed by another milestone of the first CW, RT demonstration at 3.39microm and 3.55microm, and finally the elusive result of QCL emitting at CW, RT at a wavelength as short as lambda ~3microm, a record. In

  13. Isolation, abundance and phylogenetic affiliation of endophytic actinomycetes associated with medicinal plants and screening for their in vitro antimicrobial biosynthetic potential

    PubMed Central

    Passari, Ajit K.; Mishra, Vineet K.; Saikia, Ratul; Gupta, Vijai K.; Singh, Bhim P.

    2015-01-01

    Microorganisms associated with medicinal plants are of interest as the producers of important bioactive compounds. To date, the diversity of culturable endophytic actinomycetes associated with medicinal plants is in its initial phase of exploration. In this study, 42 endophytic actinomycetes were isolated from different organs of seven selected medicinal plants. The highest number of isolates (n = 22, 52.3%) of actinomycetes was isolated from roots, followed by stems (n = 9, 21.4%), leaves (n = 6, 14.2%), flowers (n = 3, 7.1%), and petioles (n = 2, 4.7%). The genus Streptomyces was the most dominant among the isolates (66.6%) in both the locations (Dampa TRF and Phawngpuii NP, Mizoram, India). From a total of 42 isolates, 22 isolates were selected for further studies based on their ability to inhibit one of the tested human bacterial or fungal pathogen. Selected isolates were identified based on 16S rRNA gene analysis and subsequently the isolates were grouped to four different genera; Streptomyces, Brevibacterium, Microbacterium, and Leifsonia. Antibiotic sensitivity assay was performed to understand the responsible antimicrobials present in the isolates showing the antimicrobial activities and revealed that the isolates were mostly resistant to penicillin G and ampicillin. Further, antimicrobial properties and antibiotic sensitivity assay in combination with the results of amplification of biosynthetic genes polyketide synthase (PKS-I) and non-ribosomal peptide synthetase (NRPS) showed that the endophytic actinomycetes associated with the selected medicinal plants have broad-spectrum antimicrobial activity. This is the first report of the isolation of Brevibacterium sp., Microbacterium sp., and Leifsonia xyli from endophytic environments of medicinal plants, Mirabilis jalapa and Clerodendrum colebrookianum. Our results emphasize that endophytic actinomycetes associated with medicinal plants are an unexplored resource for the discovery of biologically active

  14. Isolation, abundance and phylogenetic affiliation of endophytic actinomycetes associated with medicinal plants and screening for their in vitro antimicrobial biosynthetic potential.

    PubMed

    Passari, Ajit K; Mishra, Vineet K; Saikia, Ratul; Gupta, Vijai K; Singh, Bhim P

    2015-01-01

    Microorganisms associated with medicinal plants are of interest as the producers of important bioactive compounds. To date, the diversity of culturable endophytic actinomycetes associated with medicinal plants is in its initial phase of exploration. In this study, 42 endophytic actinomycetes were isolated from different organs of seven selected medicinal plants. The highest number of isolates (n = 22, 52.3%) of actinomycetes was isolated from roots, followed by stems (n = 9, 21.4%), leaves (n = 6, 14.2%), flowers (n = 3, 7.1%), and petioles (n = 2, 4.7%). The genus Streptomyces was the most dominant among the isolates (66.6%) in both the locations (Dampa TRF and Phawngpuii NP, Mizoram, India). From a total of 42 isolates, 22 isolates were selected for further studies based on their ability to inhibit one of the tested human bacterial or fungal pathogen. Selected isolates were identified based on 16S rRNA gene analysis and subsequently the isolates were grouped to four different genera; Streptomyces, Brevibacterium, Microbacterium, and Leifsonia. Antibiotic sensitivity assay was performed to understand the responsible antimicrobials present in the isolates showing the antimicrobial activities and revealed that the isolates were mostly resistant to penicillin G and ampicillin. Further, antimicrobial properties and antibiotic sensitivity assay in combination with the results of amplification of biosynthetic genes polyketide synthase (PKS-I) and non-ribosomal peptide synthetase (NRPS) showed that the endophytic actinomycetes associated with the selected medicinal plants have broad-spectrum antimicrobial activity. This is the first report of the isolation of Brevibacterium sp., Microbacterium sp., and Leifsonia xyli from endophytic environments of medicinal plants, Mirabilis jalapa and Clerodendrum colebrookianum. Our results emphasize that endophytic actinomycetes associated with medicinal plants are an unexplored resource for the discovery of biologically active

  15. Vehicular Causation Factors and Conceptual Design Modifications to Reduce Aortic Strain in Numerically Reconstructed Real World Nearside Lateral Automotive Crashes.

    PubMed

    Belwadi, Aditya; Yang, King H

    2015-01-01

    Aortic injury (AI) leading to disruption of the aorta is an uncommon but highly lethal consequence of trauma in modern society. Most recent estimates range from 7,500 to 8,000 cases per year from a variety of causes. It is observed that more than 80% of occupants who suffer an aortic injury die at the scene due to exsanguination into the chest cavity. It is evident that effective means of substantially improving the outcome of motor vehicle crash-induced AIs is by preventing the injury in the first place. In the current study, 16 design of computer experiments (DOCE) were carried out with varying levels of principal direction of force (PDOF), impact velocity, impact height, and impact position of the bullet vehicle combined with occupant seating positions in the case vehicle to determine the effects of these factors on aortic injury. Further, a combination of real world crash data reported in the Crash Injury Research and Engineering Network (CIREN) database, Finite Element (FE) vehicle models, and the Wayne State Human Body Model-II (WSHBM-II) indicates that occupant seating position, impact height, and PDOF, in that order play, a primary role in aortic injury. PMID:26448781

  16. Vehicular Causation Factors and Conceptual Design Modifications to Reduce Aortic Strain in Numerically Reconstructed Real World Nearside Lateral Automotive Crashes

    PubMed Central

    Belwadi, Aditya; Yang, King H.

    2015-01-01

    Aortic injury (AI) leading to disruption of the aorta is an uncommon but highly lethal consequence of trauma in modern society. Most recent estimates range from 7,500 to 8,000 cases per year from a variety of causes. It is observed that more than 80% of occupants who suffer an aortic injury die at the scene due to exsanguination into the chest cavity. It is evident that effective means of substantially improving the outcome of motor vehicle crash-induced AIs is by preventing the injury in the first place. In the current study, 16 design of computer experiments (DOCE) were carried out with varying levels of principal direction of force (PDOF), impact velocity, impact height, and impact position of the bullet vehicle combined with occupant seating positions in the case vehicle to determine the effects of these factors on aortic injury. Further, a combination of real world crash data reported in the Crash Injury Research and Engineering Network (CIREN) database, Finite Element (FE) vehicle models, and the Wayne State Human Body Model-II (WSHBM-II) indicates that occupant seating position, impact height, and PDOF, in that order play, a primary role in aortic injury. PMID:26448781

  17. Geodetic Strain Analysis Tool

    NASA Technical Reports Server (NTRS)

    Kedar, Sharon; Baxter, Sean C.; Parker, Jay W.; Webb, Frank H.; Owen, Susan E.; Sibthorpe, Anthony J.; Dong, Danan

    2011-01-01

    A geodetic software analysis tool enables the user to analyze 2D crustal strain from geodetic ground motion, and create models of crustal deformation using a graphical interface. Users can use any geodetic measurements of ground motion and derive the 2D crustal strain interactively. This software also provides a forward-modeling tool that calculates a geodetic velocity and strain field for a given fault model, and lets the user compare the modeled strain field with the strain field obtained from the user s data. Users may change parameters on-the-fly and obtain a real-time recalculation of the resulting strain field. Four data products are computed: maximum shear, dilatation, shear angle, and principal components. The current view and data dependencies are processed first. The remaining data products and views are then computed in a round-robin fashion to anticipate view changes. When an analysis or display parameter is changed, the affected data products and views are invalidated and progressively re-displayed as available. This software is designed to facilitate the derivation of the strain fields from the GPS and strain meter data that sample it to facilitate the understanding of the strengths and weaknesses of the strain field derivation from continuous GPS (CGPS) and other geodetic data from a variety of tectonic settings, to converge on the "best practices" strain derivation strategy for the Solid Earth Science ESDR System (SESES) project given the CGPS station distribution in the western U.S., and to provide SESES users with a scientific and educational tool to explore the strain field on their own with user-defined parameters.

  18. Non-linear visco-elastic analysis and the design of super-pressure balloons : stress, strain and stability

    NASA Astrophysics Data System (ADS)

    Wakefield, David

    Tensys have a long-established background in the shape generation and load analysis of architectural stressed membrane structures. Founded upon their inTENS finite element analysis suite, these activities have broadened to encompass ‘lighter than air' structures such as aerostats, hybrid air-vehicles and stratospheric balloons. Since 2004 Tensys have acted as consultants to the NASA Ultra Long Duration Balloon (ULDB) Program. Early implementations of the super-pressure balloon design chosen for ULDB have shown problems of geometric instability, characterised by improper deployment and the potential for overall geometric instability once deployed. The latter has been reproduced numerically using inTENS, and the former are better understood following a series of large-scale hangar tests simulating launch and ascent. In both cases the solution lies in minimising the film lobing between the tendons. These tendons, which span between base and apex end fittings, cause the characteristic pumpkin shape of the balloons and also provide valuable constraint against excessive film deformation. There is also the requirement to generate a biaxial stress field in order to mobilise in-plane shear stiffness. A consequence of reduced lobing between tendons is the development of higher stresses in the balloon film under pressure. The different thermal characteristics between tendons and film lead to further significant meridional stress under low temperature flight conditions. The non-linear viscoelastic response of the envelope film acts positively to help dissipate excessive stress and local concentrations. However, creep over time may produce lobe geometry variations sufficient to compromise the geometric stability of the balloon. The design of a balloon requires an analysis approach that addresses the questions of stress and stability over the duration of a flight by time stepping analyses using an appropriate material model. This paper summarises the Dynamic Relaxation

  19. A new curvularin glycoside and its cytotoxic and antibacterial analogues from marine actinomycete Pseudonocardia sp. HS7.

    PubMed

    Ye, Xuewei; Anjum, Komal; Song, Tengfei; Wang, Wenling; Yu, Siran; Huang, Haocai; Lian, Xiao-Yuan; Zhang, Zhizhen

    2016-05-01

    Five curvularin macrolides (1-5) were isolated from the cultured broth of marine actinomycete Pseudonocardia sp. HS7 that was obtained from the cloacal aperture of sea cucumber Holothuria moebii. The structures of these isolates were characterized as (11S,15R)-11-hydroxycurvularin (1), (11R,15R)-11-hydroxycurvularin (2), curvularin-7-O-α-D-glucopyranoside (3), trans-dehydrocurvularin (4) and curvularin (5) based on their NMR and HRESIMS data as well as chemical degradation. Compound 3 is a new macrolide with a rare α-D-glucopyranose substituent. Compounds 1-4, 5a and 5c (the acyl products of 5), suppressed the proliferation of all six tested cancer cell lines and 4 is the most active compound with IC50 values ranging from 0.59 to 3.39 μM. The 11-hydroxycurvularins 1 and 2 also showed antibacterial activity inhibiting the growth of Escherichia coli. PMID:26119337

  20. Strain Gage

    NASA Technical Reports Server (NTRS)

    1995-01-01

    HITEC Corporation developed a strain gage application for DanteII, a mobile robot developed for NASA. The gage measured bending forces on the robot's legs and warned human controllers when acceptable forces were exceeded. HITEC further developed the technology for strain gage services in creating transducers out of "Indy" racing car suspension pushrods, NASCAR suspension components and components used in motion control.

  1. Paper Mill Effluent Decolorization by Fifty Streptomyces Strains

    PubMed Central

    Hernández, Manuel; Rodríguez, Juana; Soliveri, Juan; Copa, José L.; Pérez, María I.; Arias, María E.

    1994-01-01

    Fifty actinomycete strains isolated from lignocellulosic substrates were examined for the ability to remove the color from a paper mill effluent obtained after semichemical alkaline pulping of wheat straw. Streptomyces sp. strains UAH 15, UAH 23, UAH 30, and UAH 51 were selected for their ability to decolorize the effluent in a liquid medium containing 1% (wt/vol) glycerol, 0.2% (wt/vol) ammonium sulfate, and 80% (vol/vol) effluent. The highest levels of decolorization achieved after the strains grew were 60 to 65%. Strains UAH 30 and UAH 51 were selected for further study because of their different patterns of effluent decolorization during growth. Fractionation of the decolorized effluent by gel permeation chromatography demonstrated that there were reductions in the levels of absorbance of the high- and medium-molecular-weight compounds. These fractions were mainly responsible for the color of the effluent, while the last fractions, the low-molecular-weight compounds, could have been responsible for the residual color of the decolorized effluent. Thin-layer chromatography revealed significant differences among the patterns of bands corresponding to the acidified supernatants obtained after precipitation of alkali-lignin from the effluent samples decolorized by different Streptomyces strains. Images PMID:16349426

  2. Degradation and induction specificity in actinomycetes that degrade p-nitrophenol

    SciTech Connect

    Hanne, L.F.; Kirk, L.L.; Appel, S.M.; Narayan, A.D.; Bains, K.K. )

    1993-10-01

    We have isolated two soil bacteria (identified as Arthrobacter aurescens TW17 and Nocardia sp. strain TW2) capable of degrading p-nitrophenol (PNP) and numerous other phenolic compounds. A. aurescens TW17 contains a large plasmid which correlated with the PNP degradation phenotype. Degradation of PNP by A. aurescens TW 17 was induced by preexposure to PNP, 4-nitrocatechol, 3-methyl-4-nitrophenol, or m-nitrophenol, whereas PNP degradation by Nocardia sp. strain TW2 was induced by PNP, 4-nitrocatechol, phenol, p-cresol, or m-nitrophenol. A. aurescens TW17 initially degraded PNP to hydroquinone and nitrite. Nocardia sp. strain TW2 initially converted PNP to hydroquinone or 4-nitrocatechol, depending upon the inducing compound.

  3. Achieving high performance electric field induced strain: a rational design of hyperbranched aromatic polyamide functionalized graphene-polyurethane dielectric elastomer composites.

    PubMed

    Chen, Tian; Qiu, Jinhao; Zhu, Kongjun; Li, Jinhuan; Wang, Jingwen; Li, Shuqin; Wang, Xiaoliang

    2015-03-26

    Dielectric elastomers have great potentials as flexible actuators in micro-electromechanical systems (MEMS) due to their large deformation, light weight, mechanical compliancy, and low cost. The low dielectric constant of these elastomers requires a rather high voltage electric field, which has greatly limited their applications. In this work, a diaphragm-type flexible microactuator comprising a hyperbranched aromatic polyamide functionalized graphene (HAPFG) filler embedded into the polyurethane (PU) dielectric elastomer matrix is described. The rational designed HAPFG sheets exhibits uniform dispersion in PU matrix and strong adhesion with the matrix by hydrogen-bond coupling. Consequently, the HAPFG-PU composites possess high dielectric performance and low loss modulus. The effect of hyperbranched aromatic polyamide functionalized graphene on high voltage electric field induced strain was experimentally investigated using the Fotonic sensor. The high electric field response of the composite was discussed by applying different kinds of alternating-current field. In addition, a comparison of the breakdown strength between the HAPFG-PU composite and the pure PU was carried out. PMID:25741878

  4. Natural merodiploidy involving duplicated rpoB alleles affects secondary metabolism in a producer actinomycete.

    PubMed

    Vigliotta, Giovanni; Tredici, Salvatore Maurizio; Damiano, Fabrizio; Montinaro, Maria Rosa; Pulimeno, Rita; di Summa, Roberta; Massardo, Domenica Rita; Gnoni, Gabriele V; Alifano, Pietro

    2005-01-01

    Actinomadura sp. ATCC 39727 produces the glycopeptide antibiotic A40926, structurally similar to teicoplanin. Production of A40926 is governed by the stringent response at the transcriptional level. In fact, addition of an amino acid pool prevented the transcription of dbv cluster genes involved in the A40926 biosynthesis and the antibiotic production in chemically defined media, and a thiostrepton-resistant relaxed mutant was severely impaired in its ability to produce the antibiotic. The derivative strain rif19, highly resistant to rifampicin (minimal inhibitory concentration, MIC > 200 microg ml(-1)), was isolated from the wild type strain that exhibited low resistance to rifampicin (MIC < 25 microg ml(-1)). In this strain A40926 production started earlier than in the wild type, and reached higher final levels. Moreover, the antibiotic production was not subjected to the stringent control. Molecular analysis led to the identification of two distinct rpoB alleles, rpoBS and rpoBR, in both the wild type and the rif19. rpoBR harboured the H426N missense which is responsible for rifampicin-resistance in bacteria, in addition to other nucleotide substitutions affecting the primary structure of the RNA polymerase beta-chain. Transcript analysis revealed that rpoBR was expressed at a very low level in the wild type strain during the pseudo-exponential growth phase, and that the amount of rpoBR mRNA increased during the transition to the stationary phase. In contrast, expression of rpoBR was constitutive in the rif19. The results of mRNA half-life analysis did not support the hypothesis that post-transcriptional events are responsible for the different rpoB expression patterns in the two strains, suggesting a role of transcriptional mechanisms. PMID:15659159

  5. Geomechanical Modeling of CO2 Injection Site to Predict Wellbore Stresses and Strains for the Design of Wellbore Seal Repair Materials

    NASA Astrophysics Data System (ADS)

    Sobolik, S. R.; Gomez, S. P.; Matteo, E. N.; Stormont, J.

    2015-12-01

    This paper will present the results of large-scale three-dimensional calculations simulating the hydrological-mechanical behavior of a CO2injection reservoir and the resulting effects on wellbore casings and sealant repair materials. A critical aspect of designing effective wellbore seal repair materials is predicting thermo-mechanical perturbations in local stress that can compromise seal integrity. The DOE-NETL project "Wellbore Seal Repair Using Nanocomposite Materials," is interested in the stress-strain history of abandoned wells, as well as changes in local pressure, stress, and temperature conditions that accompany carbon dioxide injection or brine extraction. Two distinct computational models comprise the current modeling effort. The first is a field scale model that uses the stratigraphy, material properties, and injection history from a pilot CO2injection operation in Cranfield, MS to develop a stress-strain history for wellbore locations from 100 to 400 meters from an injection well. The results from the field scale model are used as input to a more detailed model of a wellbore casing. The 3D wellbore model examines the impacts of various loading scenarios on a casing structure. This model has been developed in conjunction with bench-top experiments of an integrated seal system in an idealized scaled wellbore mock-up being used to test candidate seal repair materials. The results from these models will be used to estimate the necessary mechanical properties needed for a successful repair material. This material is based upon work supported by the US Department of Energy (DOE) National Energy Technology Laboratory (NETL) under Grant Number DE-FE0009562. This project is managed and administered by the Storage Division of the NETL and funded by DOE/NETL and cost-sharing partners. This work was funded in part by the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science

  6. Geomechanical Modeling of CO2 Injection Site to Predict Wellbore Stresses and Strains for the Design of Wellbore Seal Repair Materials

    NASA Astrophysics Data System (ADS)

    Sobolik, S. R.; Gomez, S. P.; Matteo, E. N.; Stormont, J.

    2014-12-01

    This paper will present the results of large-scale three-dimensional calculations simulating the hydrological-mechanical behavior of a CO2injection reservoir and the resulting effects on wellbore casings and sealant repair materials. A critical aspect of designing effective wellbore seal repair materials is predicting thermo-mechanical perturbations in local stress that can compromise seal integrity. The DOE-NETL project "Wellbore Seal Repair Using Nanocomposite Materials," is interested in the stress-strain history of abandoned wells, as well as changes in local pressure, stress, and temperature conditions that accompany carbon dioxide injection or brine extraction. Two distinct computational models comprise the current modeling effort. The first is a field scale model that uses the stratigraphy, material properties, and injection history from a pilot CO2injection operation in Cranfield, MS to develop a stress-strain history for wellbore locations from 100 to 400 meters from an injection well. The results from the field scale model are used as input to a more detailed model of a wellbore casing. The 3D wellbore model examines the impacts of various loading scenarios on a casing structure. This model has been developed in conjunction with bench-top experiments of an integrated seal system in an idealized scaled wellbore mock-up being used to test candidate seal repair materials. The results from these models will be used to estimate the necessary mechanical properties needed for a successful repair material. This material is based upon work supported by the US Department of Energy (DOE) National Energy Technology Laboratory (NETL) under Grant Number DE-FE0009562. This project is managed and administered by the Storage Division of the NETL and funded by DOE/NETL and cost-sharing partners. This work was funded in part by the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science

  7. Geomechanical Modeling of CO2 Injection Site to Predict Wellbore Stresses and Strains for the Design of Wellbore Seal Repair Materials

    NASA Astrophysics Data System (ADS)

    Sobolik, S. R.; Matteo, E. N.; Dewers, T. A.; Newell, P.; Gomez, S. P.; Stormont, J.

    2014-12-01

    This paper will present the results of large-scale three-dimensional calculations simulating the hydrological-mechanical behavior of a CO2 injection reservoir and the resulting effects on wellbore casings and sealant repair materials. A critical aspect of designing effective wellbore seal repair materials is predicting thermo-mechanical perturbations in local stress that can compromise seal integrity. The DOE-NETL project "Wellbore Seal Repair Using Nanocomposite Materials," is interested in the stress-strain history of abandoned wells, as well as changes in local pressure, stress, and temperature conditions that accompany carbon dioxide injection or brine extraction. Two distinct computational models comprise the current modeling effort. The first is a field scale model that uses the stratigraphy, material properties, and injection history from a pilot CO2 injection operation in Cranfield, MS to develop a stress-strain history for wellbore locations from 100 to 400 meters from an injection well. The results from the field scale model are used as input to a more detailed model of a wellbore casing. The 3D wellbore model examines the impacts of various loading scenarios on a casing structure. This model has been developed in conjunction with bench-top experiments of an integrated seal system in an idealized scaled wellbore mock-up being used to test candidate seal repair materials. The results from these models will be used to estimate the necessary mechanical properties needed for a successful repair material. This material is based upon work supported by the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) under Grant Number DE-FE0009562. This project is managed and administered by the University of New Mexico and funded by DOE/NETL and cost-sharing partners. This work was funded in part by the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of

  8. Three-dimensional mapping of mechanical activation patterns, contractile dyssynchrony and dyscoordination by two-dimensional strain echocardiography: Rationale and design of a novel software toolbox

    PubMed Central

    De Boeck, Bart WL; Kirn, Borut; Teske, Arco J; Hummeling, Ralph W; Doevendans, Pieter A; Cramer, Maarten J; Prinzen, Frits W

    2008-01-01

    Background Dyssynchrony of myocardial deformation is usually described in terms of variability only (e.g. standard deviations SD's). A description in terms of the spatio-temporal distribution pattern (vector-analysis) of dyssynchrony or by indices estimating its impact by expressing dyscoordination of shortening in relation to the global ventricular shortening may be preferential. Strain echocardiography by speckle tracking is a new non-invasive, albeit 2-D imaging modality to study myocardial deformation. Methods A post-processing toolbox was designed to incorporate local, speckle tracking-derived deformation data into a 36 segment 3-D model of the left ventricle. Global left ventricular shortening, standard deviations and vectors of timing of shortening were calculated. The impact of dyssynchrony was estimated by comparing the end-systolic values with either early peak values only (early shortening reserve ESR) or with all peak values (virtual shortening reserve VSR), and by the internal strain fraction (ISF) expressing dyscoordination as the fraction of deformation lost internally due to simultaneous shortening and stretching. These dyssynchrony parameters were compared in 8 volunteers (NL), 8 patients with Wolff-Parkinson-White syndrome (WPW), and 7 patients before (LBBB) and after cardiac resynchronization therapy (CRT). Results Dyssynchrony indices merely based on variability failed to detect differences between WPW and NL and failed to demonstrate the effect of CRT. Only the 3-D vector of onset of shortening could distinguish WPW from NL, while at peak shortening and by VSR, ESR and ISF no differences were found. All tested dyssynchrony parameters yielded higher values in LBBB compared to both NL and WPW. CRT reduced the spatial divergence of shortening (both vector magnitude and direction), and improved global ventricular shortening along with reductions in ESR and dyscoordination of shortening expressed by ISF. Conclusion Incorporation of local 2-D

  9. Streptomyces lunalinharesii strain 235 shows the potential to inhibit bacteria involved in biocorrosion processes.

    PubMed

    Pacheco da Rosa, Juliana; Korenblum, Elisa; Franco-Cirigliano, Marcella Novaes; Abreu, Fernanda; Lins, Ulysses; Soares, Rosângela M A; Macrae, Andrew; Seldin, Lucy; Coelho, Rosalie R R

    2013-01-01

    Four actinomycete strains previously isolated from Brazilian soils were tested for their antimicrobial activity against Bacillus pumilus LF-4 and Desulfovibrio alaskensis NCIMB 13491, bacteria that are well known to be involved in biofilm formation and biocorrosion. Strain 235, belonging to the species Streptomyces lunalinharesii, inhibited the growth of both bacteria. The antimicrobial activity was seen over a wide range of pH, and after treatment with several chemicals and heat but not with proteinase K and trypsin. The antimicrobial substances present in the concentrated supernatant from growth media were partially characterized by SDS-PAGE and extracellular polypeptides were seen. Bands in the size range of 12 to 14.4 kDa caused antimicrobial activity. Transmission electron microscopy of D. alaskensis cells treated with the concentrated supernatant containing the antimicrobial substances revealed the formation of prominent bubbles, the spherical double-layered structures on the cell membrane, and the periplasmic space completely filled with electron-dense material. This is the first report on the production of antimicrobial substances by actinomycetes against bacteria involved in biocorrosion processes, and these findings may be of great relevance as an alternative source of biocides to those currently employed in the petroleum industry. PMID:23484107

  10. Streptomyces lunalinharesii Strain 235 Shows the Potential to Inhibit Bacteria Involved in Biocorrosion Processes

    PubMed Central

    Pacheco da Rosa, Juliana; Korenblum, Elisa; Franco-Cirigliano, Marcella Novaes; Abreu, Fernanda; Lins, Ulysses; Soares, Rosângela M. A.; Macrae, Andrew; Seldin, Lucy; Coelho, Rosalie R. R.

    2013-01-01

    Four actinomycete strains previously isolated from Brazilian soils were tested for their antimicrobial activity against Bacillus pumilus LF-4 and Desulfovibrio alaskensis NCIMB 13491, bacteria that are well known to be involved in biofilm formation and biocorrosion. Strain 235, belonging to the species Streptomyces lunalinharesii, inhibited the growth of both bacteria. The antimicrobial activity was seen over a wide range of pH, and after treatment with several chemicals and heat but not with proteinase K and trypsin. The antimicrobial substances present in the concentrated supernatant from growth media were partially characterized by SDS-PAGE and extracellular polypeptides were seen. Bands in the size range of 12 to 14.4 kDa caused antimicrobial activity. Transmission electron microscopy of D. alaskensis cells treated with the concentrated supernatant containing the antimicrobial substances revealed the formation of prominent bubbles, the spherical double-layered structures on the cell membrane, and the periplasmic space completely filled with electron-dense material. This is the first report on the production of antimicrobial substances by actinomycetes against bacteria involved in biocorrosion processes, and these findings may be of great relevance as an alternative source of biocides to those currently employed in the petroleum industry. PMID:23484107

  11. Strain isolated ceramic coatings

    NASA Technical Reports Server (NTRS)

    Tolokan, R. P.; Brady, J. B.; Jarrabet, G. P.

    1985-01-01

    Plasma sprayed ceramic coatings are used in gas turbine engines to improve component temperature capability and cooling air efficiency. A compliant metal fiber strain isolator between a plasma sprayed ceramic coating and a metal substrate improves ceramic durability while allowing thicker coatings for better insulation. Development of strain isolated coatings has concentrated on design and fabrication of coatings and coating evaluation via thermal shock testing. In thermal shock testing, five types of failure are possible: buckling failure im compression on heat up, bimetal type failure, isothermal expansion mismatch failure, mudflat cracking during cool down, and long term fatigue. A primary failure mode for thermally cycled coatings is designated bimetal type failure. Bimetal failure is tensile failure in the ceramic near the ceramic-metal interface. One of the significant benefits of the strain isolator is an insulating layer protecting the metal substrate from heat deformation and thereby preventing bimetal type failure.

  12. Amycolatopsis rhabdoformis sp. nov., an actinomycete isolated from a tropical forest soil.

    PubMed

    Souza, Wallace Rafael; Silva, Rafael Eduardo; Goodfellow, Michael; Busarakam, Kanungnid; Figueiro, Fernanda Sales; Ferreira, Douglas; Rodrigues-Filho, Edson; Moraes, Luiz Alberto Beraldo; Zucchi, Tiago Domingues

    2015-06-01

    Strain SB026T was isolated from Brazilian rainforest soil and its taxonomic position established using data from a polyphasic study. The organism showed a combination of chemotaxonomic and morphological features consistent with its classification in the genus Amycolatopsis and formed a branch in the Amycolatopsis 16S rRNA gene tree together with Amycolatopsis bullii NRRL B-24847T, Amycolatopsis plumensis NRRL B-24324T, Amycolatopsis tolypomycina DSM 44544T and Amycolatopsis vancoresmycina NRRL B-24208T. It was related most closely to A. bullii NRRL B-24847T (99.0 % 16S rRNA gene sequence similarity), but was distinguished from this strain by a low level of DNA-DNA relatedness (~46 %) and discriminatory phenotypic properties. Based on the combined genotypic and phenotypic data, it is proposed that the isolate should be classified in the genus Amycolatopsis as representing a novel species, Amycolatopsis rhabdoformis sp. nov. The type strain is SB026T ( = CBMAI 1694T = CMAA 1285T = NCIMB 14900T). PMID:25744584

  13. Structure of an MmyB-Like Regulator from C. aurantiacus, Member of a New Transcription Factor Family Linked to Antibiotic Metabolism in Actinomycetes

    PubMed Central

    Xu, Qingping; van Wezel, Gilles P.; Chiu, Hsiu-Ju; Jaroszewski, Lukasz; Klock, Heath E.; Knuth, Mark W.; Miller, Mitchell D.; Lesley, Scott A.; Godzik, Adam; Elsliger, Marc-André; Deacon, Ashley M.; Wilson, Ian A.

    2012-01-01

    Actinomycetes are important bacterial sources of antibiotics and other secondary metabolites. Many antibiotic gene clusters are controlled by pathway-specific activators that act in response to growth conditions. Here we present the crystal structure of an MmyB-like transcription regulator MltR (PDB code 3pxp) (Caur_2278) from Chloroflexus aurantiacus, in complex with a fatty acid (myristic acid). MltR is a distant homolog of the methylenomycin activator MmyB and consists of an Xre-type N-terminal DNA-binding domain and a C-terminal ligand-binding module that is related to the Per-Arnt-Sim (PAS) domain. This structure has enabled identification of a new family of bacterial transcription factors that are distributed predominantly in actinomycetes. Bioinformatics analysis of MltR and other characterized family members suggest that they are likely associated with antibiotic and fatty acid metabolism in actinomycetes. Streptomyces coelicolor SCO4944 is a candidate as an ancestral member of the family. Its ortholog in S. griseus, SGR_6891, is induced by A-factor, a γ-butyrolactone that controls antibiotic production and development, and is adjacent to the A-factor synthase gen, afsA. The location of mltR/mmyB homologs, in particular those adjacent to less well-studied antibiotic-related genes, makes them interesting genetic markers for identifying new antibiotic genes. A model for signal-triggered DNA-binding by MltR is proposed. PMID:22844465

  14. Improvement of LysM-Mediated Surface Display of Designed Ankyrin Repeat Proteins (DARPins) in Recombinant and Nonrecombinant Strains of Lactococcus lactis and Lactobacillus Species

    PubMed Central

    Zadravec, Petra; Štrukelj, Borut

    2015-01-01

    Safety and probiotic properties make lactic acid bacteria (LAB) attractive hosts for surface display of heterologous proteins. Protein display on nonrecombinant microorganisms is preferred for therapeutic and food applications due to regulatory requirements. We displayed two designed ankyrin repeat proteins (DARPins), each possessing affinity for the Fc region of human IgG, on the surface of Lactococcus lactis by fusing them to the Usp45 secretion signal and to the peptidoglycan-binding C terminus of AcmA, containing lysine motif (LysM) repeats. Growth medium containing a secreted fusion protein was used to test its heterologous binding to 10 strains of species of the genus Lactobacillus, using flow cytometry, whole-cell enzyme-linked immunosorbent assay (ELISA), and fluorescence microscopy. The fusion proteins bound to the surfaces of all lactobacilli; however, binding to the majority of bacteria was only 2- to 5-fold stronger than that of the control. Lactobacillus salivarius ATCC 11741 demonstrated exceptionally strong binding (32- to 55-fold higher than that of the control) and may therefore be an attractive host for nonrecombinant surface display. Genomic comparison of the species indicated the exopolysaccharides of Lb. salivarius as a possible reason for the difference. Additionally, a 15-fold concentration-dependent increase in nonrecombinant surface display on L. lactis was demonstrated by growing bacteria with sublethal concentrations of the antibiotics chloramphenicol and erythromycin. Nonrecombinant surface display on LAB, based on LysM repeats, was optimized by selecting Lactobacillus salivarius ATCC 11741 as the optimal host and by introducing antibiotics as additives for increasing surface display on L. lactis. Additionally, effective display of DARPins on the surfaces of nonrecombinant LAB has opened up several new therapeutic possibilities. PMID:25576617

  15. Cloning and recombinant expression of a cellulase from the cellulolytic strain Streptomyces sp. G12 isolated from compost

    PubMed Central

    2012-01-01

    Background The use of lignocellulosic materials for second generation ethanol production would give several advantages such as minimizing the conflict between land use for food and fuel production, providing less expensive raw materials than conventional agricultural feedstock, allowing lower greenhouse gas emissions than those of first generation ethanol. However, cellulosic biofuels are not produced at a competitive level yet, mainly because of the high production costs of the cellulolytic enzymes. Therefore, this study was aimed at discovering new cellulolytic microorganisms and enzymes. Results Different bacteria isolated from raw composting materials obtained from vegetable processing industry wastes were screened for their cellulolytic activity on solid medium containing carboxymethylcellulose. Four strains belonging to the actinomycetes group were selected on the basis of their phenotypic traits and cellulolytic activity on solid medium containing carboxymethylcellulose. The strain showing the highest cellulolytic activity was identified by 16S rRNA sequencing as belonging to Streptomyces genus and it was designated as Streptomyces sp. strain G12. Investigating the enzymes responsible for cellulase activity produced by Streptomyces G12 by proteomic analyses, two endoglucanases were identified. Gene coding for one of these enzymes, named CelStrep, was cloned and sequenced. Molecular analysis showed that the celstrep gene has an open reading frame encoding a protein of 379 amino acid residues, including a signal peptide of 37 amino acid residues. Comparison of deduced aminoacidic sequence to the other cellulases indicated that the enzyme CelStrep can be classified as a family 12 glycoside hydrolase. Heterologous recombinant expression of CelStrep was carried out in Escherichia coli, and the active recombinant enzyme was purified from culture supernatant and characterized. It catalyzes the hydrolysis of carboxymethylcellulose following a Michaelis

  16. Comparative analysis of mycobacterium and related actinomycetes yields insight into the evolution of mycobacterium tuberculosis pathogenesis

    PubMed Central

    2012-01-01

    Background The sequence of the pathogen Mycobacterium tuberculosis (Mtb) strain H37Rv has been available for over a decade, but the biology of the pathogen remains poorly understood. Genome sequences from other Mtb strains and closely related bacteria present an opportunity to apply the power of comparative genomics to understand the evolution of Mtb pathogenesis. We conducted a comparative analysis using 31 genomes from the Tuberculosis Database (TBDB.org), including 8 strains of Mtb and M. bovis, 11 additional Mycobacteria, 4 Corynebacteria, 2 Streptomyces, Rhodococcus jostii RHA1, Nocardia farcinia, Acidothermus cellulolyticus, Rhodobacter sphaeroides, Propionibacterium acnes, and Bifidobacterium longum. Results Our results highlight the functional importance of lipid metabolism and its regulation, and reveal variation between the evolutionary profiles of genes implicated in saturated and unsaturated fatty acid metabolism. It also suggests that DNA repair and molybdopterin cofactors are important in pathogenic Mycobacteria. By analyzing sequence conservation and gene expression data, we identify nearly 400 conserved noncoding regions. These include 37 predicted promoter regulatory motifs, of which 14 correspond to previously validated motifs, as well as 50 potential noncoding RNAs, of which we experimentally confirm the expression of four. Conclusions Our analysis of protein evolution highlights gene families that are associated with the adaptation of environmental Mycobacteria to obligate pathogenesis. These families include fatty acid metabolism, DNA repair, and molybdopterin biosynthesis. Our analysis reinforces recent findings suggesting that small noncoding RNAs are more common in Mycobacteria than previously expected. Our data provide a foundation for understanding the genome and biology of Mtb in a comparative context, and are available online and through TBDB.org. PMID:22452820

  17. Geodermatophilus telluris sp. nov., an actinomycete isolated from Saharan desert sand.

    PubMed

    Montero-Calasanz, Maria del Carmen; Göker, Markus; Pötter, Gabriele; Rohde, Manfred; Spröer, Cathrin; Schumann, Peter; Klenk, Hans-Peter; Gorbushina, Anna A

    2013-06-01

    A novel Gram-positive, multiloculated thalli-forming, aerobic, actinobacterial strain, CF9/1/1(T), was isolated in 2007 during environmental screening for xerophilic fungi in arid desert soil from the Sahara desert, Chad. The isolate grew best at a temperature range of 20-35 °C and at pH 6.0-8.5 and with 0-4% (w/v) NaCl, forming black-coloured and irregular colonies on GYM agar. Chemotaxonomic and molecular characteristics of the isolate matched those described for members of the genus Geodermatophilus. The DNA G+C content of the novel strain was 75.4 mol%. The peptidoglycan contained meso-diaminopimelic acid as a diagnostic diamino acid. The main phospholipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, a not yet structurally identified aminophospholipid and a small amount of phosphatidylglycerol; MK-9(H4) was identified as the dominant menaquinone and galactose was a diagnostic sugar. The major cellular fatty acids were branched-chain saturated acids: iso-C16:0 and iso-C15:0. The 16S rRNA gene sequence of the isolate showed 94.6-97.0% sequence similarities with those of five members of the genus: Geodermatophilus ruber DSM 45317(T) (94.6%), Geodermatophilus obscurus DSM 43160(T) (94.8%), Geodermatophilus siccatus DSM 45419(T) (96.2%), Geodermatophilus nigrescens DSM 45408(T) (96.7%) and Geodermatophilus arenarius DSM 45418(T) (97.0%). Based on the evidence from this polyphasic taxonomic study, a novel species, Geodermatophilus telluris sp. nov., is proposed; the type strain is CF9/1/1(T) (=DSM 45421(T)=CCUG 62764(T)). PMID:23159748

  18. [Yeast cell wall-dissolving enzymes of the thermotolerant actinomycete Thermoactinomyces vulgaris].

    PubMed

    Loginova, L G; Iakovleva, M B; Golovina, I G; Bogdanova, T I

    1976-01-01

    The thermotolerant culture of Thermoactinomyces vulgaris PA II-4A was cultivated in the Biotec fermenter to obtain the enzyme preparation with a high proteolytic and lytic activity. Resistance of the cells of Candida utilis and Saccharomyces fragilis (mesophilic and thermotolerant strains) to the lytic action of the enzyme preparation was different. Preliminary treatment of the yeast cells by L-cysteine increased their susceptibility to the lytic action of the preparation. The degree of lysis of the cells depended also on their age: the cells growing during 10-12 hours were lysed easier than the cells cultivated during 24 hours. PMID:6860

  19. Analysis of pFQ31, a 8551-bp cryptic plasmid from the symbiotic nitrogen-fixing actinomycete Frankia.

    PubMed

    Lavire, C; Louis, D; Perrière, G; Briolay, J; Normand, P; Cournoyer, B

    2001-04-01

    The actinomycete Frankia has never been transformed genetically. To favour the development of Frankia cloning vectors, we have fully sequenced the Frankia alni pFQ31 cryptic plasmid and performed analyses to characterise its coding and non-coding regions. This plasmid is 8551 bp-long and contains 72% G+C. Computer-assisted analyses identified 18 open reading frames (ORFs). These ORFs show a synonymous codon usage different from the one of Frankia chromosomal genes, suggesting an evolutionary bias linked to the nature of the replicon or a horizontal transfer. Three ORFs were found to encode genes likely to be involved in plasmid replication and stability: parFA (partition protein), ptrFA (transcriptional repressor of the GntR family) and repFA (initiation of replication). DNA signatures of a replication origin were identified in the ptrFA-repFA intergenic region. These structural motifs are similar to those observed among origins of iteron-containing plasmids replicating via a θ mode. PMID:11287155

  20. Complete genome sequence of Saccharomonospora viridis type strain (P101T)

    SciTech Connect

    Pati, Amrita; Sikorski, Johannes; Nolan, Matt; Lapidus, Alla; Copeland, Alex; Glavina Del Rio, Tijana; Lucas, Susan; Chen, Feng; Tice, Hope; Pitluck, Sam; Cheng, Jan-Fang; Chertkov, Olga; Brettin, Thomas; Han, Cliff; Detter, John C.; Kuske, Cheryl; Bruce, David; Goodwin, Lynne; Chain, Patrick; D'haeseleer, Patrik; Chen, Amy; Palaniappan, Krishna; Ivanova, Natalia; Mavromatis, Konstantinos; Mikhailova, Natalia; Rohde, Manfred; Tindall, Brian J.; Goker, Markus; Bristow, Jim; Eisen, Jonathan A.; Markowitz, Victor; Hugenholtz, Philip; Kyrpides1, Nikos C.; Klenk, Hans-Peter

    2009-05-20

    Saccharomonospora viridis (Schuurmans et al. 1956) Nonomurea and Ohara 1971 is the type species of the genus Saccharomonospora which belongs to the family Pseudonocardiaceae. S. viridis is of interest because it is a Gram-negative organism classified amongst the usually Gram-positive actinomycetes. Members of the species are frequently found in hot compost and hay, and its spores can cause farmer?s lung disease, bagassosis, and humidifier fever. Strains of the species S. viridis have been found to metabolize the xenobiotic pentachlorophenol (PCP). The strain described in this study has been isolated from peat-bog in Ireland. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the family Pseudonocardiaceae, and the 4,308,349 bp long single replicon genome with its 3906 protein-coding and 64 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.

  1. Natural Diversity of Frankia Strains in Actinorhizal Root Nodules from Promiscuous Hosts in the Family Myricaceae

    PubMed Central

    Clawson, Michael L.; Benson, David R.

    1999-01-01

    Actinorhizal plants invade nitrogen-poor soils because of their ability to form root nodule symbioses with N2-fixing actinomycetes known as Frankia. Frankia strains are difficult to isolate, so the diversity of strains inhabiting nodules in nature is not known. To address this problem, we have used the variability in bacterial 16S rRNA gene sequences amplified from root nodules as a means to estimate molecular diversity. Nodules were collected from 96 sites primarily in northeastern North America; each site contained one of three species of the family Myricaceae. Plants in this family are considered to be promiscuous hosts because several species are effectively nodulated by most isolated strains of Frankia in the greenhouse. We found that strain evenness varies greatly between the plant species so that estimating total strain richness of Frankia within myricaceous nodules with the sample size used was problematical. Nevertheless, Myrica pensylvanica, the common bayberry, was found to have sufficient diversity to serve as a reservoir host for Frankia strains that infect plants from other actinorhizal families. Myrica gale, sweet gale, yielded a few dominant sequences, indicating either symbiont specialization or niche selection of particular ecotypes. Strains in Comptonia peregrina nodules had an intermediate level of diversity and were all from a single major group of Frankia. PMID:10508084

  2. Study on the flocculability of the Arthrobacter sp., an actinomycete resuscitated from the VBNC state.

    PubMed

    Su, Xiaomei; Shen, Xiuying; Ding, Linxian; Yokota, Akira

    2012-01-01

    A bioflocculant with high flocculating activity, LC13-SF, produced by strain LC13(T) which was in a viable but nonculturable (VBNC) state, and which was woken up by Rpf (resuscitation promoting factor), was systematically investigated with regard to its fermentation conditions and flocculating activity. The key parameters influencing the bioflocculant LC13-SF were investigated through measuring the optical density at 660 (OD(660)) of the fermentation liquid and the optical density at 550 (OD(550)) of the centrifugal supernatant. The flocculating efficiency and the Zeta potentials were chosen as the response variables for the study of the flocculating activity. The results showed that the optimal conditions for bioflocculant LC13-SF production were a fermentation time of 72 h, an initial pH of 7.0, a fermentation temperature of 30°C and a shaking speed of 150 r/min. The optimized flocculating process was as follows: a final volume percentage of bioflocculant LC13-SF and 0.5% (w/w) CaCl(2) were 1.5 and 5%, respectively in a 4 g/L Kaolin suspension, and the system pH was adjusted to 8.0. Under these conditions, the flocculating efficiency and the absolute value of the Zeta potential reached 94.83% and 4.37, respectively. PMID:22806783

  3. A marine algicidal actinomycete and its active substance against the harmful algal bloom species Phaeocystis globosa.

    PubMed

    Zheng, Xiaowei; Zhang, Bangzhou; Zhang, Jinlong; Huang, Liping; Lin, Jing; Li, Xinyi; Zhou, Yanyan; Wang, Hui; Yang, Xiaoru; Su, Jianqiang; Tian, Yun; Zheng, Tianling

    2013-10-01

    A strain O4-6, which had pronounced algicidal effects to the harmful algal bloom causing alga Phaeocystis globosa, was isolated from mangrove sediments in the Yunxiao Mangrove National Nature Reserve, Fujian, China. Based on the 16S rRNA gene sequence and morphological characteristics, the isolate was found to be phylogenetically related to the genus Streptomyces and identified as Streptomyces malaysiensis O4-6. Heat stability, pH tolerance, molecular weight range and aqueous solubility were tested to characterize the algicidal compound secreted from O4-6. Results showed that the algicidal activity of this compound was not heat stable and not affected by pH changes. Residue extracted from the supernatant of O4-6 fermentation broth by ethyl acetate, was purified by Sephadex LH-20 column and silica gel column chromatography before further structure determination. Chemical structure of the responsible compound, named NIG355, was illustrated based on quadrupole time-of-flight mass spectrometry (Q-TOF-MS) and nuclear magnetic resonance (NMR) spectra. And this compound showed a stronger algicidal activity compared with other reported algicides. Furthermore, this article represents the first report of an algicide against P. globosa, and the compound may be potentially used as a bio-agent for controlling harmful algal blooms. PMID:23224407

  4. Hip flexor strain - aftercare

    MedlinePlus

    Pulled hip flexor - aftercare; Hip flexor injury - aftercare; Hip flexor tear - aftercare; Iliopsoas strain - aftercare; Strained iliopsoas muscle - aftercare; Torn iliopsoas muscle - aftercare; Psoas strain - aftercare

  5. Sannastatin, a novel toxic macrolactam polyketide glycoside produced by actinomycete Streptomyces sannanensis.

    PubMed

    Yang, Sheng-Xiang; Gao, Jin-Ming; Zhang, An-Ling; Laatsch, Hartmut

    2011-07-01

    A new rare 20-membered macrocyclic lactam incorporating a diene conjugated olefin, designated sannastatin (1), together with the known structurally related vicenistatin (2), has been isolated from the cultures of Streptomyces sannanensis, a bacteria found in the feces of Ailuropoda melanoleuca. The structure of the new compound was established on the basis of extensive spectroscopic analyses including 1D- and 2D-NMR ((1)H-(1)H COSY, TOCSY, HSQC, HMBC, and NOESY) experiments. Compounds 1 and 2 displayed significant growth inhibitory activity against the brine shrimp (Artemia salina) larvae. PMID:21640585

  6. Design

    ERIC Educational Resources Information Center

    Buchanan, Richard; Cross, Nigel; Durling, David; Nelson, Harold; Owen, Charles; Valtonen, Anna; Boling, Elizabeth; Gibbons, Andrew; Visscher-Voerman, Irene

    2013-01-01

    Scholars representing the field of design were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Richard Buchanan, Nigel Cross, David Durling, Harold Nelson, Charles Owen, and Anna Valtonen. Scholars…

  7. Production of Induced Secondary Metabolites by a Co-Culture of Sponge-Associated Actinomycetes, Actinokineospora sp. EG49 and Nocardiopsis sp. RV163

    PubMed Central

    Dashti, Yousef; Grkovic, Tanja; Abdelmohsen, Usama Ramadan; Hentschel, Ute; Quinn, Ronald J.

    2014-01-01

    Two sponge-derived actinomycetes, Actinokineospora sp. EG49 and Nocardiopsis sp. RV163, were grown in co-culture and the presence of induced metabolites monitored by 1H NMR. Ten known compounds, including angucycline, diketopiperazine and β-carboline derivatives 1–10, were isolated from the EtOAc extracts of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163. Co-cultivation of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163 induced the biosynthesis of three natural products that were not detected in the single culture of either microorganism, namely N-(2-hydroxyphenyl)-acetamide (11), 1,6-dihydroxyphenazine (12) and 5a,6,11a,12-tetrahydro-5a,11a-dimethyl[1,4]benzoxazino[3,2-b][1,4]benzoxazine (13a). When tested for biological activity against a range of bacteria and parasites, only the phenazine 12 was active against Bacillus sp. P25, Trypanosoma brucei and interestingly, against Actinokineospora sp. EG49. These findings highlight the co-cultivation approach as an effective strategy to access the bioactive secondary metabolites hidden in the genomes of marine actinomycetes. PMID:24857962

  8. Evaluation of Matrix-Assisted Laser Desorption Ionization−Time of Flight Mass Spectrometry for Identification of Mycobacterium species, Nocardia species, and Other Aerobic Actinomycetes

    PubMed Central

    Buckwalter, S. P.; Olson, S. L.; Connelly, B. J.; Lucas, B. C.; Rodning, A. A.; Walchak, R. C.; Deml, S. M.; Wohlfiel, S. L.

    2015-01-01

    The value of matrix-assisted laser desorption ionization−time of flight mass spectrometry (MALDI-TOF MS) for the identification of bacteria and yeasts is well documented in the literature. Its utility for the identification of mycobacteria and Nocardia spp. has also been reported in a limited scope. In this work, we report the specificity of MALDI-TOF MS for the identification of 162 Mycobacterium species and subspecies, 53 Nocardia species, and 13 genera (totaling 43 species) of other aerobic actinomycetes using both the MALDI-TOF MS manufacturer's supplied database(s) and a custom database generated in our laboratory. The performance of a simplified processing and extraction procedure was also evaluated, and, similar to the results in an earlier literature report, our viability studies confirmed the ability of this process to inactivate Mycobacterium tuberculosis prior to analysis. Following library construction and the specificity study, the performance of MALDI-TOF MS was directly compared with that of 16S rRNA gene sequencing for the evaluation of 297 mycobacteria isolates, 148 Nocardia species isolates, and 61 other aerobic actinomycetes isolates under routine clinical laboratory working conditions over a 6-month period. MALDI-TOF MS is a valuable tool for the identification of these groups of organisms. Limitations in the databases and in the ability of MALDI-TOF MS to rapidly identify slowly growing mycobacteria are discussed. PMID:26637381

  9. Evaluation of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Mycobacterium species, Nocardia species, and Other Aerobic Actinomycetes.

    PubMed

    Buckwalter, S P; Olson, S L; Connelly, B J; Lucas, B C; Rodning, A A; Walchak, R C; Deml, S M; Wohlfiel, S L; Wengenack, N L

    2016-02-01

    The value of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for the identification of bacteria and yeasts is well documented in the literature. Its utility for the identification of mycobacteria and Nocardia spp. has also been reported in a limited scope. In this work, we report the specificity of MALDI-TOF MS for the identification of 162 Mycobacterium species and subspecies, 53 Nocardia species, and 13 genera (totaling 43 species) of other aerobic actinomycetes using both the MALDI-TOF MS manufacturer's supplied database(s) and a custom database generated in our laboratory. The performance of a simplified processing and extraction procedure was also evaluated, and, similar to the results in an earlier literature report, our viability studies confirmed the ability of this process to inactivate Mycobacterium tuberculosis prior to analysis. Following library construction and the specificity study, the performance of MALDI-TOF MS was directly compared with that of 16S rRNA gene sequencing for the evaluation of 297 mycobacteria isolates, 148 Nocardia species isolates, and 61 other aerobic actinomycetes isolates under routine clinical laboratory working conditions over a 6-month period. MALDI-TOF MS is a valuable tool for the identification of these groups of organisms. Limitations in the databases and in the ability of MALDI-TOF MS to rapidly identify slowly growing mycobacteria are discussed. PMID:26637381

  10. Novel strained superjunction VDMOS

    NASA Astrophysics Data System (ADS)

    Naugarhiya, Alok; Dubey, Shashank; Kondekar, Pravin N.

    2015-09-01

    In this paper, we have proposed novel strained superjunction (s-SJ) vertical double diffused MOS (VDMOS). Through channel engineering, we have introduced strain effects in s-SJ device using thin separate p-type silicon-germanium (p-SiGe) layer over silicon p-pillar. Further, we have designed process flow for the possible fabrication of s-SJ VDMOS. The proposed s-SJ devices fitted with less input capacitance (Cin) and 1.2∼3 times higher output current density than conventional SJ VDMOS. Therefore, 40% less gate charge (Qg) is required to turn-on the s-SJ VDMOS and Ron A is optimized in between 12% and 46%.

  11. Numerical demonstration of MEMS strain sensor

    NASA Astrophysics Data System (ADS)

    Saboonchi, Hossain; Ozevin, Didem

    2012-04-01

    Silicon has piezoresistive property that allows designing strain sensor with higher gauge factor compared to conventional metal foil gauges. The sensing element can be micro-scale using MEMS, which minimizes the effect of strain gradient on measurement at stress concentration regions such as crack tips. The challenge of MEMS based strain sensor design is to decouple the sensing element from substrate for true strain measurement and to compensate the temperature effect on the piezoresistive coefficients of silicon. In this paper, a family of MEMS strain sensors with different geometric designs is introduced. Each strain sensor is made of single crystal silicon and manufactured using deposition/ etching/oxidation steps on a n- doped silicon wafer in (100) plane. The geometries include sensing element connected to the free heads of U shape substrate, a set of two or more sensing elements in an array in order to capture strain gradients and two directional sensors. The response function and the gauge factor of the strain sensors are identified using multi-physics models that combine structural and electrical behaviors of sensors mounted on a strained structure. The relationship between surface strain and strain at microstructure is identified numerically in order to include the relationship in the response function calculation.

  12. High temperature strain gage apparent strain compensation

    NASA Technical Reports Server (NTRS)

    Holmes, Harlan K.; Moore, T. C., Sr.

    1992-01-01

    Once an installed strain gage is connected to a strain indicating device and the instrument is balanced, a subsequent change in temperature of the gage installation will generally produce a resistance change in the gage. This purely temperature-induced resistance will be registered by the indicating device as a strain and is referred to as 'apparent strain' to distinguish it from strain due to applied stress. One desirable technique for apparent strain compensation is to employ two identical gages with identical mounting procedures which are connected with a 'half bridge' configuration where gages see the same thermal environment but only one experiences a mechanical strain input. Their connection in adjacent arms of the bridge will then balance the thermally induced apparent strains and, in principle, only the mechanical strain remains. Two approaches that implement this technique are discussed.

  13. Morphological, biochemical, and serological studies on 64 strains of Actinomyces israelii.

    PubMed

    Slack, J M; Landfried, S; Gerencser, M A

    1969-02-01

    A comparative study of 64 strains of Actinomyces israelii was done with the use of techniques standardized by the Subgroup on Taxonomy of the Microaerophilic Actinomycetes. Emphasis was placed on the range of variation to assist recognition of clinical isolates and aid in differentiation from Actinomyces-like organisms. None of the strains was positive for catalase or indole, or in the Voges-Proskauer test; 90% were methyl red-positive and 62% were nitrate-positive. Acid was produced from: glucose (100%), xylose (100%), salicin (98%), raffinose (95%), lactose (89%), cellobiose (83%), mannose (78%), arabinose (76%), inositol (58%), mannitol (48%), starch (31%), glycogen (0%), glycerol (0%), and rhamnose (0%). A. israelii can be identified by the fluorescent-antibody method, but there is no single morphological or biochemical characteristic which can be used for its identification. By both fluorescent-antibody and gel-diffusion techniques, the serological classification of A. israelii group D with serotypes 1 and 2 was verified. Eleven serotype 2 strains were compared morphologically, biochemically, and serologically with 53 serotype 1 strains. All but two of the serotype 2 strains produced viscous growth in broth and none fermented arabinose. PMID:4975155

  14. Complete genome sequence of Nakamurella multipartita type strain (Y-104T)

    SciTech Connect

    Tice, Hope; Mayilraj, Shanmugam; Sims, David; Lapidus, Alla L.; Nolan, Matt; Lucas, Susan; Glavina Del Rio, Tijana; Copeland, A; Cheng, Jan-Fang; Meincke, Linda; Bruce, David; Goodwin, Lynne A.; Pitluck, Sam; Ivanova, N; Mavromatis, K; Ovchinnikova, Galina; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Land, Miriam L; Hauser, Loren John; Chang, Yun-Juan; Jeffries, Cynthia; Detter, J. Chris; Rohde, Manfred; Goker, Markus; Bristow, James; Eisen, Jonathan; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C; Klenk, Hans-Peter; Chen, Feng

    2010-01-01

    Nakamurella multipartita (Yoshimi et al. 1996) Tao et al. 2004 is the type species of the small one-species genus Nakamurella in the actinomycetal suborder Frankineae. The nonmotile, coccus-shaped strain was isolated from activated sludge acclimated with sugar-containing synthetic wastewater, and is able of accumulating large amounts of polysaccharides in its cells. Here we describe the features of the organism, together with the complete genome sequence and annotation. This is the first complete genome sequence of a member of the family Nakamurellaceae. The 6,060,298 bp long single replicon genome with its 5415 protein-coding and 53 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.

  15. Competitiveness of a Genetically Engineered Strain of Trichoderma virens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The intraspecific competitiveness of a genetically engineered strain of Trichoderma virens was assessed relative to the non-transformed, progenitor strain and an isogenic, auxotrophic strain using a replacement series design. The transformed strain was less fit, but appeared more competitive than t...

  16. Geobacteraceae strains and methods

    DOEpatents

    Lovley, Derek R.; Nevin, Kelly P.; Yi, Hana

    2015-07-07

    Embodiments of the present invention provide a method of producing genetically modified strains of electricigenic microbes that are specifically adapted for the production of electrical current in microbial fuel cells, as well as strains produced by such methods and fuel cells using such strains. In preferred embodiments, the present invention provides genetically modified strains of Geobacter sulfurreducens and methods of using such strains.

  17. Strain actuated aeroelastic control

    NASA Technical Reports Server (NTRS)

    Lazarus, Kenneth B.

    1992-01-01

    Viewgraphs on strain actuated aeroelastic control are presented. Topics covered include: structural and aerodynamic modeling; control law design methodology; system block diagram; adaptive wing test article; bench-top experiments; bench-top disturbance rejection: open and closed loop response; bench-top disturbance rejection: state cost versus control cost; wind tunnel experiments; wind tunnel gust alleviation: open and closed loop response at 60 mph; wind tunnel gust alleviation: state cost versus control cost at 60 mph; wind tunnel command following: open and closed loop error at 60 mph; wind tunnel flutter suppression: open loop flutter speed; and wind tunnel flutter suppression: closed loop state cost curves.

  18. Strains and Sprains

    MedlinePlus

    ... Children's Sports Injuries Computer-Related Repetitive Stress Injuries Knee Injuries Broken Bones, Sprains, and Strains Strains and Sprains ... Pain Going to a Physical Therapist Hamstring Strain Knee Injuries Sports and Exercise Safety Dealing With Sports Injuries ...

  19. Muscle strain (image)

    MedlinePlus

    A muscle strain is the stretching or tearing of muscle fibers. A muscle strain can be caused by sports, exercise, a ... something that is too heavy. Symptoms of a muscle strain include pain, tightness, swelling, tenderness, and the ...

  20. Muscle strain treatment

    MedlinePlus

    Treatment - muscle strain ... Question: How do you treat a muscle strain ? Answer: Rest the strained muscle and apply ice for the first few days after the injury. Anti-inflammatory medicines or acetaminophen ( ...

  1. Strainrange partitioning: A total strain range version

    NASA Technical Reports Server (NTRS)

    Halford, G. R.; Saltsman, J. F.

    1983-01-01

    Procedures are presented for expressing the Strainrange Partitioning (SRP) method for creep fatigue life prediction in terms of total strain range. Inelastic and elastic strain-range - life relations are summed to give total strain-range - life relations. The life components due to inelastic strains are dealt with using conventional SRP procedures while the life components due to elastic strains are expressed as families of time-dependent terms for each type of SRP cycle. Cyclic constitutive material behavior plays an important role in establishing the elastic strain-range - life relations as well as the partitioning of the inelastic strains. To apply the approach, however, it is not necessary to have to determine the magnitude of the inelastic strain range. The total strain SRP approach is evaluated and verified using two nickel base superalloys, AF2-1DA and Rene 95. Excellent agreement is demonstrated between observed and predicted cyclic lifetimes with 70 to 80 percent of the predicted lives falling within factors of two of the observed lives. The total strain-range SRP approach should be of considerable practical value to designers who are faced with creep-fatigue problems for which the inelastic strains cannot be calculated with sufficient accuracy to make reliable life predictions by the conventional inelastic strain range SRP approach.

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

    PubMed

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

    2016-02-01

    Strain ATCC 39727, which produces the antibiotic A40926 (the natural precursor of the antibiotic dalbavancin), was isolated from a soil sample collected in India, and it was originally classified as a member of the genus Actinomadura on the base of morphology and cell-wall composition. A phylogenetic analysis based on 16S rRNA gene sequences indicates that the strain forms a distinct clade within the genus Nonomuraea, and it is most closely related to Nonomuraea angiospora DSM 43173T (98.72 % similarity) and Nonomuraea jabiensis A4036T (98.69 %). The strain forms an extensively branched substrate mycelium and aerial hyphae that form spiral chains of spores with ridged surfaces. The cell wall contains meso-diaminopimelic acid and the whole-cell sugars are glucose, ribose, galactose, mannose and madurose (madurose as the diagnostic sugar). The N-acyl type of muramic acid is acetyl. The predominant menaquinone is MK-9(H4), with minor amounts of MK-9(H2), MK-9(H6) and MK-9(H0). The polar-lipid profile includes diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylmethylethanolamine, hydroxyphosphatidylmethylethanolamine, phosphatidylinositol and a series of uncharacterized phospholipids, glycolipids and phosphoglycolipids. The major cellular fatty acids are iso-C16 : 0 and 10-methyl C17 : 0. The genomic DNA G+C content is 71.2 mol%. Significant differences in the morphological, chemotaxonomic and biochemical data, together with DNA-DNA relatedness between strain ATCC 39727 and closely related type strains, clearly demonstrated that strain ATCC 39727 represents a novel species of the genus Nonomuraea, for which the name Nonomuraea gerenzanensis sp. nov. is proposed. The type strain is ATCC 39727T ( = DSM 100948T). PMID:26944798

  3. Thick film wireless and powerless strain sensor

    NASA Astrophysics Data System (ADS)

    Jia, Yi; Sun, Ke

    2006-03-01

    The development of an innovative wireless strain sensing technology has a great potential to extend its applications in manufacturing, civil engineering and aerospace industry. This paper presents a novel wireless and powerless strain sensor with a multi-layer thick film structure. The sensor employs a planar inductor (L) and capacitive transducer (C) resonant tank sensing circuit, and a strain sensitive material of a polarized polyvinylidene fluoride (PVDF) piezoelectric thick film to realize the wireless strain sensing by strain to frequency conversion and to receive radio frequency electromagnetic energy for powering the sensor. The prototype sensor was designed and fabricated. The results of calibration on a strain constant cantilever beam show a great linearity and sensitivity about 0.0013 in a strain range of 0-0.018.

  4. Atypical OmpR/PhoB Subfamily Response Regulator GlnR of Actinomycetes Functions as a Homodimer, Stabilized by the Unphosphorylated Conserved Asp-focused Charge Interactions*

    PubMed Central

    Lin, Wei; Wang, Ying; Han, Xiaobiao; Zhang, Zilong; Wang, Chengyuan; Wang, Jin; Yang, Huaiyu; Lu, Yinhua; Jiang, Weihong; Zhao, Guo-Ping; Zhang, Peng

    2014-01-01

    The OmpR/PhoB subfamily protein GlnR of actinomycetes is an orphan response regulator that globally coordinates the expression of genes related to nitrogen metabolism. Biochemical and genetic analyses reveal that the functional GlnR from Amycolatopsis mediterranei is unphosphorylated at the potential phosphorylation Asp50 residue in the N-terminal receiver domain. The crystal structure of this receiver domain demonstrates that it forms a homodimer through the α4-β5-α5 dimer interface highly similar to the phosphorylated typical response regulator, whereas the so-called “phosphorylation pocket” is not conserved, with its space being occupied by an Arg52 from the β3-α3 loop. Both in vitro and in vivo experiments confirm that GlnR forms a functional homodimer via its receiver domain and suggest that the charge interactions of Asp50 with the highly conserved Arg52 and Thr9 in the receiver domain may be crucial in maintaining the proper conformation for homodimerization, as also supported by molecular dynamics simulations of the wild type GlnR versus the deficient mutant GlnR(D50A). This model is backed by the distinct phenotypes of the total deficient GlnR(R52A/T9A) double mutant versus the single mutants of GlnR (i.e. D50N, D50E, R52A and T9A), which have only minor effects upon both dimerization and physiological function of GlnR in vivo, albeit their DNA binding ability is weakened compared with that of the wild type. By integrating the supportive data of GlnRs from the model Streptomyces coelicolor and the pathogenic Mycobacterium tuberculosis, we conclude that the actinomycete GlnR is atypical with respect to its unphosphorylated conserved Asp residue being involved in the critical Arg/Asp/Thr charge interactions, which is essential for maintaining the biologically active homodimer conformation. PMID:24733389

  5. Medically Complex Home Care and Caregiver Strain

    ERIC Educational Resources Information Center

    Moorman, Sara M.; Macdonald, Cameron

    2013-01-01

    Purpose of the study: To examine (a) whether the content of caregiving tasks (i.e., nursing vs. personal care) contributes to variation in caregivers' strain and (b) whether the level of complexity of nursing tasks contributes to variation in strain among caregivers providing help with such tasks. Design and methods: The data came from the Cash…

  6. Whole genome sequences of four Brucella strains.

    PubMed

    Ding, Jiabo; Pan, Yuanlong; Jiang, Hai; Cheng, Junsheng; Liu, Taotao; Qin, Nan; Yang, Yi; Cui, Buyun; Chen, Chen; Liu, Cuihua; Mao, Kairong; Zhu, Baoli

    2011-07-01

    Brucella melitensis and Brucella suis are intracellular pathogens of livestock and humans. Here we report four genome sequences, those of the virulent strain B. melitensis M28-12 and vaccine strains B. melitensis M5 and M111 and B. suis S2, which show different virulences and pathogenicities, which will help to design a more effective brucellosis vaccine. PMID:21602346

  7. Program Calibrates Strain Gauges

    NASA Technical Reports Server (NTRS)

    Okazaki, Gary D.

    1991-01-01

    Program dramatically reduces personnel and time requirements for acceptance tests of hardware. Data-acquisition system reads output from Wheatstone full-bridge strain-gauge circuit and calculates strain by use of shunt calibration technique. Program nearly instantaneously tabulates and plots strain data against load-cell outputs. Modified to acquire strain data for other specimens wherever full-bridge strain-gauge circuits used. Written in HP BASIC.

  8. Superlattice strain gage

    DOEpatents

    Noel, Bruce W.; Smith, Darryl L.; Sinha, Dipen N.

    1990-01-01

    A strain gage comprising a strained-layer superlattice crystal exhibiting piezoelectric properties is described. A substrate upon which such a strained-layer superlattice crystal has been deposited is attached to an element to be monitored for strain. A light source is focused on the superlattice crystal and the light reflected from, passed through, or emitted from the crystal is gathered and compared with previously obtained optical property data to determine the strain in the element.

  9. Superlattice strain gage

    DOEpatents

    Noel, B.W.; Smith, D.L.; Sinha, D.N.

    1988-06-28

    A strain gage comprising a strained-layer superlattice crystal exhibiting piezoelectric properties is described. A substrate upon which such a strained-layer superlattice crystal has been deposited is attached to an element to be monitored for strain. A light source is focused on the superlattice crystal and the light reflected from, passed through, or emitted from the crystal is gathered and compared with previously obtained optical property data to determine the strain in the element. 8 figs.

  10. Miniature biaxial strain transducer

    NASA Technical Reports Server (NTRS)

    Hoffman, I. S. (Inventor)

    1976-01-01

    A reusable miniature strain transducer for use in the measurement of static or quasi-static, high level, biaxial strain on the surface of test specimens or structures was studied. Two cantilever arms, constructed by machining the material to appropriate flexibility, are self-aligning and constitute the transducing elements of the device. Used in conjunction with strain gages, the device enables testing beyond normal gage limits for high strains and number of load cycles. The device does not require conversion computations since the electrical output of the strain gages is directly proportional to the strain measured.

  11. Construction of expression vectors for metabolic engineering of the vanillin-producing actinomycete Amycolatopsis sp. ATCC 39116.

    PubMed

    Fleige, Christian; Steinbüchel, Alexander

    2014-01-01

    Amycolatopsis sp. ATCC 39116 is able to synthesize the important flavoring agent vanillin from cheap natural substrates. The bacterium is therefore of great interest for the industry and used for the fermentative production of vanillin. In order to improve the production of natural vanillin with Amycolatopsis sp. ATCC 39116, the strain has been genetically engineered to optimize the metabolic flux towards the desired product. Extensive metabolic engineering was hitherto hampered, due to the lack of genetic tools like functional promoters and expression vectors. In this study, we report the establishment of a plasmid-based gene expression system for Amycolatopsis sp. ATCC 39116 that allows a further manipulation of the genotype. Four new Escherichia coli-Amycolatopsis shuttle vectors harboring different promoter elements were constructed, and the functionality of these regulatory elements was proven by the expression of the reporter gene gusA, encoding a β-glucuronidase. Glucuronidase activity was detected in all plasmid-harboring strains, and remarkable differences in the expression strength of the reporter gene depending on the used promoter were observed. The new expression vectors will promote the further genetic engineering of Amycolatopsis sp. ATCC 39116 to get insight into the metabolic network and to improve the strain for a more efficient industrial use. PMID:24743982

  12. Isolation and partial characterization of antimicrobial compounds from a new strain Nonomuraea sp. NM94.

    PubMed

    Badji, Boubekeur; Mostefaoui, Abdellah; Sabaou, Nasserdine; Lebrihi, Ahmed; Mathieu, Florence; Seguin, Elisabeth; Tillequin, François

    2007-06-01

    An actinomycete strain NM94 was isolated from a Saharan soil sample by a dilution agar plating method using chitin-vitamins B medium supplemented with penicillin. The strain presented the morphological and chemical characteristics of the genus Nonomuraea. On the basis of 16S rDNA analysis and physiological tests, this isolate was found to be quite different from the known species of Nonomuraea and might be new. The strain NM94 secreted several antibiotics on yeast extract malt extract glucose medium that were active against some Gram-positive bacteria, yeast, and fungi. The antibiotics were extracted with dichloromethane and detected by bioautography on silica gel plates using Mucor ramannianus and Bacillus subtilis as the test organisms. Among these antibiotics, a complex called 94A showed interesting antifungal activity. It was selected and purified by reverse-phase HPLC. This complex was composed of five compounds. Spectroscopic studies by infrared, mass, and (1)H NMR of the compounds were carried out. Initial results showed that these molecules differed from the known antibiotics produced by other Nonomuraea species. PMID:17318487

  13. Effects of systematic clinical supervision on psychiatric nurses' sense of coherence, creativity, work-related strain, job satisfaction and view of the effects from clinical supervision: a pre-post test design.

    PubMed

    Berg, A; Hallberg, I R

    1999-10-01

    There are few investigations of the type and the outcome of interventions aimed at supporting nurses caring for psychiatric patients. Therefore a prepost-test design study was used in which 22 psychiatric nurses, on a general psychiatric ward were examined before, during and after one year of systematic clinical supervision combined with supervised documented, planned, individualized care. The methods used were the Sense of Coherence scale (SOC), the Creative Climate Questionnaire (CCQ), the Work-Related Strain Inventory and 34 statements from the Satisfaction with Nursing Care and Work Questionnaire (SNCW). In addition 14 statements were developed to evaluate the nurses' view of the effects from clinical supervision. The baseline values for the CCQ indicated a stagnant organization and a high score in the conflict dimension indicated personal and emotional tensions within the organization. The intervention led to a significantly increased creative and innovative climate in the dimensions for trust, idea time and reduced conflicts. However, the organizational climate remained stagnant. The nurses' view of the effects from clinical supervision also increased significantly. There were no significant changes in the nurses' SNCW, WRSI or SOC score. The result of the correlation analysis indicated that a strong sense of coherence was related to low work-related strain but not to unsatisfactory working conditions/milieu. The results gave some support to the idea that systematic clinical supervision and supervised nursing care plans constitute one type of support strategy that improves creativity and the organizational climate. It may, not, however, buffer for interpersonal problems. Further research is required to explore the need for effects of various support systems depending on the circumstances in the organization. PMID:10827645

  14. Strains and Sprains

    MedlinePlus

    ... move the injured part, and you might even think you have broken a bone. How Does a Strain or Sprain Happen? Strains often happen when you put a lot of pressure on a muscle or you push it too far, such as when lifting a heavy object. Strains may be more likely to happen if ...

  15. Sprains and Strains

    MedlinePlus

    ... happens. A strain is a stretched or torn muscle or tendon. Tendons are tissues that connect muscle to bone. Twisting or pulling these tissues can ... suddenly or develop over time. Back and hamstring muscle strains are common. Many people get strains playing ...

  16. Can a strain yield a qubit?

    NASA Astrophysics Data System (ADS)

    Benjamin, Colin

    2015-03-01

    A Josepshon qubit is designed via the application of a tensile strain to a topological insulator surface, sandwiched between two s-wave superconductors. The strain applied leads to a shift in Dirac point without changing the conducting states existing on the surface of a topological insulator. This strain applied can be tuned to form a π-junction in such a structure. Combining two such junctions in a ring architecture leads to the ground state of the ring being in a doubly degenerate state- ``0'' and ``1'' states of the qubit. A qubit designed this way is easily controlled via the tunable strain. We report on the conditions necessary to design such a qubit. Finally the operating time of a single qubit phase gate is derived. This work was supported by funds from Dept. of Science and Technology (Nanomission), Govt. of India, Grant No. SR/NM/NS-1101/2011.

  17. New Orientia tsutsugamushi strain from scrub typhus in Australia.

    PubMed Central

    Odorico, D. M.; Graves, S. R.; Currie, B.; Catmull, J.; Nack, Z.; Ellis, S.; Wang, L.; Miller, D. J.

    1998-01-01

    In a recent case of scrub typhus in Australia, Orientia tsutsugamushi isolated from the patient's blood was tested by sequence analysis of the 16S rDNA gene. The sequence showed a strain of O. tsutsugamushi that was quite different from the classic Karp, Kato, and Gilliam strains. The new strain has been designated Litchfield. PMID:9866742

  18. AN ORGANOTYPIC UNIAXIAL STRAIN MODEL USING MICROFLUIDICS

    PubMed Central

    Dollé, Jean-Pierre; Morrison, Barclay; Schloss, Rene R.; Yarmush, Martin L.

    2012-01-01

    Traumatic brain injuries are the leading cause of disability each year in the US. The most common and devastating consequence is the stretching of axons caused by shear deformation that occurs during rotational acceleration of the brain during injury. The injury effects on axonal molecular and functional events are not fully characterized. We have developed a strain injury model that maintains the three dimensional cell architecture and neuronal networks found in vivo with the ability to visualize individual axons and their response to a mechanical injury. The advantage of this model is that it can apply uniaxial strains to axons that make functional connections between two organotypic slices and injury responses can be observed in real-time and over long term. This uniaxial strain model was designed to be capable of applying an array of mechanical strains at various rates of strain, thus replicating a range of modes of axonal injury. Long term culture, preservation of slice and cell orientation, and slice-slice connection on the device was demonstrated. The device has the ability to strain either individual axons or bundles of axons through the control of microchannel dimensions. The fidelity of the model was verified by observing characteristic responses to various strain injuries which included axonal beading, delayed elastic effects and breakdown in microtubules. Microtubule breakdown was shown to be dependent on the degree of the applied strain field, where maximal breakdown was observed at peak strain and minimal breakdown is observed at low strain. This strain injury model could be a powerful tool in assessing strain injury effects on functional axonal connections. PMID:23233120

  19. Effects of plant stress signal molecules on the production of wilforgine in an endophytic actinomycete isolated from Tripterygium wilfordii Hook.f.

    PubMed

    Miao, Guo-peng; Zhu, Chuan-shu; Feng, Jun-tao; Han, Li-rong; Zhang, Xing

    2015-04-01

    The endophytic actinomycete F4-20 was isolated from Tripterygium wilfordii Hook.f. and was confirmed to produce wilforgine, a secondary metabolite discovered in its host. F4-20 showed a close phylogenetic relationship to Streptomyces species. To seek elicitors that may enhance the production of wilforgine in F4-20, four plant stress molecules were applied to the in vitro liquid cultures. Results showed that methyl jasmonate (MeJA), salicylic acid (SA), and hydrogen peroxide (H2O2) inhibited bacterial growth, whereas glutathione (GSH) treatment significantly increased bacterial growth. The wilforgine contents in the mycelia of F4-20 were reduced by MeJA and GSH but were induced by SA and H2O2. When added in the end of the culture period (7 day), 1 mM SA and 5 mM H2O2 resulted in 69.35 ± 1.71 and 71.80 ± 3.35 µg/g DW of wilforgine production, 1.55 and 1.60 fold to that of control (44.83 ± 1.35 µg/g DW), respectively. Though this improved production was about 6.5 times lower than that of the natural root (454.00 µg/g dry root bark), it provided an alternative method for the production of valuable plant secondary metabolites. PMID:25523369

  20. Antifungal properties of an actinomycin D-producing strain, Streptomyces sp. IA1, isolated from a Saharan soil.

    PubMed

    Toumatia, Omrane; Yekkour, Amine; Goudjal, Yacine; Riba, Amar; Coppel, Yannick; Mathieu, Florence; Sabaou, Nasserdine; Zitouni, Abdelghani

    2015-02-01

    An actinomycete strain named IA1, which produced an antimicrobial compound, was isolated from a Saharan soil in In Amenas, Algeria. The study of the 16S rDNA sequence of this strain permitted to relate it to Streptomyces mutabilis NBRC 12800(T) (99.93% of similarity). Strain IA1 exhibited strong activity against a wide range of plant pathogenic fungi. One bioactive compound produced in large amounts (46.7 mg L(-1)  day(-1) ), named YA, was isolated and purified by TLC and reverse phase HPLC. The structure elucidation of the pure substance, using combined data from UV visible, NMR spectra, and mass spectrometry, permitted to identify it as actinomycin D, and was thus found for the first time in S. mutabilis related species. The biocontrol abilities of the strain IA1 and compound YA were evaluated through two diseases, i.e., chocolate spot of field bean and Fusarium wilt of flax. The occurrence of the two fungal diseases was effectively reduced. The reduction of chocolate spot disease symptoms reached 80 and 91.7% with IA1 and YA seedlings pretreatments, respectively. Soil pretreatment with IA1 or YA also allowed to reduce Fusarium wilt disease impact by almost 60%. PMID:25284744

  1. Elastocaloric cooling processes: The influence of material strain and strain rate on efficiency and temperature span

    NASA Astrophysics Data System (ADS)

    Schmidt, Marvin; Schütze, Andreas; Seelecke, Stefan

    2016-06-01

    This paper discusses the influence of material strain and strain rate on efficiency and temperature span of elastocaloric cooling processes. The elastocaloric material, a newly developed quaternary Ni-Ti-Cu-V alloy, is characterized at different maximum strains and strain rates. The experiments are performed with a specially designed test setup, which enables the measurement of mechanical and thermal process parameters. The material efficiency is compared to the efficiency of the Carnot process at equivalent thermal operation conditions. This method allows for a direct comparison of the investigated material with other caloric materials.

  2. Genome-Based Discovery of a Novel Membrane-Bound 1,6-Dihydroxyphenazine Prenyltransferase from a Marine Actinomycete

    PubMed Central

    Zeyhle, Philipp; Bauer, Judith S.; Kalinowski, Jörn; Shin-ya, Kazuo; Gross, Harald; Heide, Lutz

    2014-01-01

    Recently, novel prenylated derivatives of 1,6-dihydroxyphenazine have been isolated from the marine sponge-associated Streptomyces sp. SpC080624SC-11. Genome sequencing of this strain now revealed a gene cluster containing all genes necessary for the synthesis of the phenazine and the isoprenoid moieties. Unexpectedly, however, the cluster did not contain a gene with similarity to previously investigated phenazine prenyltransferases, but instead a gene with modest similarity to the membrane-bound prenyltransferases of ubiquinone and menaquinone biosynthesis. Expression of this gene in E. coli and isolation of the membrane fraction proved that the encoded enzyme, Mpz10, catalyzes two successive prenylations of 1,6-dihydroxyphenazine. Mpz10 is the first example of a membrane-bound enzyme catalyzing the prenylation of a phenazine substrate, and one of few examples of membrane-bound enzymes involved in the prenylation of aromatic secondary metabolites in microorganisms. PMID:24892559

  3. Strain gage balances and buffet gages

    NASA Technical Reports Server (NTRS)

    Ferris, A. T.

    1983-01-01

    One-piece strain gage force balances were developed for use in the National Transonic Facility (NTF). This was accomplished by studying the effects of the cryogenic environment on materials, strain gages, cements, solders, and moisture proofing agents, and selecting those that minimized strain gage output changes due to temperature. In addition, because of the higher loads that may be imposed by the NTF, these balances are designed to carry a larger load for a given diameter than conventional balances. Full cryogenic calibrations were accomplished, and wind tunnel results that were obtained from the Langley 0-3-Meter Transonic Cryogenic Tunnel were used to verify laboratory test results.

  4. High Temperature Capacitive Strain Gage

    NASA Technical Reports Server (NTRS)

    Wnuk, Stephen P., Jr.; Wnuk, Stephen P., III; Wnuk, V. P.

    1990-01-01

    Capacitive strain gages designed for measurements in wind tunnels to 2000 F were built and evaluated. Two design approaches were followed. One approach was based on fixed capacitor plates with a movable ground plane inserted between the plates to effect differential capacitive output with strain. The second approach was based on movable capacitor plates suspended between sapphire bearings, housed in a rugged body, and arranged to operate as a differential capacitor. A sapphire bearing gage (1/4 in. diameter x 1 in. in size) was built with a range of 50,000 and a resolution of 200 microstrain. Apparent strain on Rene' 41 was less than + or - 1000 microstrain from room temperature to 2000 F. Three gage models were built from the Ground Plane Differential concept. The first was 1/4 in. square by 1/32 in. high and useable to 700 F. The second was 1/2 in. square by 1/16 in. high and useable to 1440 F. The third, also 1/2 in. square by 1/16 in. high was expected to operate in the 1600 to 2000 F range, but was not tested because time and funding ended.

  5. The Development of Electrical Strain Gages

    NASA Technical Reports Server (NTRS)

    De Forest, A V; Leaderman, H

    1940-01-01

    The design, construction, and properties of an electrical-resistance strain gage consisting of fine wires molded in a laminated plastic are described. The properties of such gages are discussed and also the problems of molding of wires in plastic materials, temperature compensation, and cementing and removal of the gages. Further work to be carried out on the strain gage, together with instrument problems, is discussed.

  6. Strain limit criteria to predict failure

    SciTech Connect

    Flanders, H.E.

    1995-12-31

    In recent years extensive effort has been expended to qualify existing structures for conditions that are beyond the original design basis. Determination of the component failure load is useful for this type of evaluation. This paper presents criteria based upon strain limits to predict the load at failure. The failure modes addressed are excessive plastic deformations, localized plastic strains, and structural instability. The effects of analytical method sophistication, as built configurations, material properties degradation, and stress state are addressed by the criteria.

  7. Elevated temperature strain gages

    NASA Technical Reports Server (NTRS)

    Brittain, J. O.; Geslin, D.; Lei, J. F.

    1986-01-01

    One of the goals of the HOST Program is the development of electrical resistance strain gages for static strain measurements at temperatures equal to or greater than 1273 K. Strain gage materials must have a reproducible or predictable response to temperature, time and strain. It is the objective of this research to investigate criteria for the selection of materials for such applications through electrical properties studies. The results of the investigation of two groups of materials, refractory compounds and binary alloy solid solutions are presented.

  8. Thin film strain transducer

    NASA Technical Reports Server (NTRS)

    Rand, J. L. (Inventor)

    1984-01-01

    A strain transducer system and process for making the same is disclosed. A beryllium copper ring having four strain gages is electrically connected in Wheatstone bridge fashion to the output instrumentation. Tabs are bonded to a balloon or like surface with strain on the surface causing bending of a ring which provides an electrical signal through the gages proportional to the surface strain. A photographic pattern of a one half ring segment as placed on a sheet of beryllium copper for chem-mill etch formation is illustrated.

  9. Can strain magnetize light?

    NASA Astrophysics Data System (ADS)

    2013-02-01

    Strain in photonic structures can induce pseudomagnetic fields and Landau levels. Nature Photonics spoke to Mordechai Segev, Mikael Rechtsman, Alexander Szameit and Julia Zeuner about their unique approach.

  10. Mechanical strain isolator mount

    NASA Technical Reports Server (NTRS)

    James, Gordon E. (Inventor)

    1991-01-01

    Certain devices such as optical instruments must preserve their alignmental integrity while being subjected to mechanical strain. A mechanical strain isolator mount is provided to preserve the alignmental integrity of an alignment sensitive instrument. An alignment sensitive instrument is mounted on a rectangular base. Flexural legs are connected at their proximal ends to the rectangular base. Flexural legs are also spaced parallel to the sides. Mounting pads are connected to the legs at the distal end and the mechanical strain isolator mount is attached to the substrate by means of threaded bolts. When a mounting pad and its respective leg is subjected to lateral strain in either the X or Y direction via the substrate, the respective leg relieves the strain by bending in the direction of the strain. An axial strain on a mounting pad in the Z direction is relieved by a rotational motion of the legs in the direction of the strain. When the substrate is stress free, the flexural legs return to their original condition and thus preserve the original alignment integrity of the alignment sensitive instrument.

  11. Light intensity strain analysis

    NASA Technical Reports Server (NTRS)

    Williams, J. G. (Inventor)

    1973-01-01

    A process is described for the analysis of the strain field of structures subjected to large deformations involving a low modulus substrate having a high modulus, relatively thin coating. The optical properties of transmittance and reflectance are measured for the coated substrate while stressed and unstressed to indicate the strain field for the coated substrate.

  12. Quantitative Use of Fluorescent In Situ Hybridization To Examine Relationships between Mycolic Acid-Containing Actinomycetes and Foaming in Activated Sludge Plants

    PubMed Central

    Davenport, Russell J.; Curtis, Thomas P.; Goodfellow, Michael; Stainsby, Fiona M.; Bingley, Marc

    2000-01-01

    The formation of viscous foams on aeration basins and secondary clarifiers of activated sludge plants is a common and widespread problem. Foam formation is often attributed to the presence of mycolic acid-containing actinomycetes (mycolata). In order to examine the relationship between the number of mycolata and foam, we developed a group-specific probe targeting the 16S rRNA of the mycolata, a protocol to permeabilize mycolata, and a statistically robust quantification method. Statistical analyses showed that a lipase-based permeabilization method was quantitatively superior to previously described methods (P << 0.05). When mixed liquor and foam samples were examined, most of the mycolata present were rods or cocci, although filamentous mycolata were also observed. A nested analysis of variance showed that virtually all of the measured variance occurred between fields of view and not between samples. On this basis we determined that as few as five fields of view could be used to give a statistically meaningful sample. Quantitative fluorescent in situ hybridization (FISH) was used to examine the relationship between foaming and the concentration of mycolata in a 20-m3 completely mixed activated sludge plant. Foaming occurred when the number of mycolata exceeded a certain threshold value. Baffling of the plant affected foaming without affecting the number of mycolata. We tentatively estimated that the threshold foaming concentration of mycolata was about 2 × 106 cells ml−1 or 4 × 1012 cells m−2. We concluded that quantitative use of FISH is feasible and that quantification is a prerequisite for rational investigation of foaming in activated sludge. PMID:10698786

  13. Two Master Switch Regulators Trigger A40926 Biosynthesis in Nonomuraea sp. Strain ATCC 39727

    PubMed Central

    Lo Grasso, Letizia; Maffioli, Sonia; Sosio, Margherita; Bibb, Mervyn; Puglia, Anna Maria

    2015-01-01

    ABSTRACT The actinomycete Nonomuraea sp. strain ATCC 39727 produces the glycopeptide A40926, the precursor of dalbavancin. Biosynthesis of A40926 is encoded by the dbv gene cluster, which contains 37 protein-coding sequences that participate in antibiotic biosynthesis, regulation, immunity, and export. In addition to the positive regulatory protein Dbv4, the A40926-biosynthetic gene cluster encodes two additional putative regulators, Dbv3 and Dbv6. Independent mutations in these genes, combined with bioassays and liquid chromatography-mass spectrometry (LC-MS) analyses, demonstrated that Dbv3 and Dbv4 are both required for antibiotic production, while inactivation of dbv6 had no effect. In addition, overexpression of dbv3 led to higher levels of A40926 production. Transcriptional and quantitative reverse transcription (RT)-PCR analyses showed that Dbv4 is essential for the transcription of two operons, dbv14-dbv8 and dbv30-dbv35, while Dbv3 positively controls the expression of four monocistronic transcription units (dbv4, dbv29, dbv36, and dbv37) and of six operons (dbv2-dbv1, dbv14-dbv8, dbv17-dbv15, dbv21-dbv20, dbv24-dbv28, and dbv30-dbv35). We propose a complex and coordinated model of regulation in which Dbv3 directly or indirectly activates transcription of dbv4 and controls biosynthesis of 4-hydroxyphenylglycine and the heptapeptide backbone, A40926 export, and some tailoring reactions (mannosylation and hexose oxidation), while Dbv4 directly regulates biosynthesis of 3,5-dihydroxyphenylglycine and other tailoring reactions, including the four cross-links, halogenation, glycosylation, and acylation. IMPORTANCE This report expands knowledge of the regulatory mechanisms used to control the biosynthesis of the glycopeptide antibiotic A40926 in the actinomycete Nonomuraea sp. strain ATCC 39727. A40926 is the precursor of dalbavancin, approved for treatment of skin infections by Gram-positive bacteria. Therefore, understanding the regulation of its biosynthesis

  14. Imploding Liner Material Strength Measurements at High-Strain and High Strain Rate

    SciTech Connect

    Bartsch, R.R.; Lee, H.; Holtkamp, D.; Wright, B.; Stokes, J.; Morgan, D.; Anderson, W.; Broste, W.

    1998-10-18

    Imploding, cylindrical liners provide a unique, shockless means of simultaneously accessing high strain and high-strain-rate for measurement of strength of materials in plastic flow. The radial convergence in the liner geometry results in the liner thickening as the circumference becomes smaller. Strains of up to {approximately}1.25 and strain rates of up to {approximately}10{sup 6} sec{sup -1} can be readily achieved in a material sample placed inside of an aluminum driver liner, using the Pegasus II capacitor bank. This provides yield strength data at conditions where none presently exists. The heating from work done against the yield strength is measured with multichannel pyrometry from infrared radiation emitted by the material sample. The temperature data as a function of liner position are unfolded to give the yield strength along the strain, strain-rate trajectory. Proper design of the liner and sample configuration ensures that the current diffused into the sample adds negligible heating. An important issue, in this type of temperature measurement, is shielding of the pickup optics from other sources of radiation. At strains greater than those achievable on Pegasus, e.g. the LANL Atlas facility, some materials may be heated all the way to melt by this process. Recent data on 6061-T6 Aluminum will be compared with an existing model for strain and strain-rate heating. The liner configuration and pyrometry diagnostic will also be discussed.

  15. Absolute strain measurements made with fiber Bragg grating sensors

    NASA Astrophysics Data System (ADS)

    Song, In C.; Lee, Sun K.; Jeong, Sung H.; Lee, Byeong H.

    2004-02-01

    A strain sensor system based on optical fiber Bragg gratings (FBGs) is proposed with a new matched-filter design. The strain variation on the sensor FBG is continuously followed and matched by a filter FBG by use of a feedback control loop that produces an identical strain condition on the filter FBG. The matched strain on the filter FBG is then determined from the resonance vibration of the fiber piece embedding the filter FBG. The implementation and the performance of the proposed system are described. It is demonstrated that the proposed system can distinguish strain variation on the sensor FBG with resolution of one microstrain.

  16. Actinoquinolines A and B, anti-inflammatory quinoline alkaloids from a marine-derived Streptomyces sp., strain CNP975.

    PubMed

    Hassan, Hossam M; Boonlarppradab, Chollaratt; Fenical, William

    2016-07-01

    Actinomycete bacteria of the common genus Streptomyces can be routinely isolated from shallow and deep ocean sediments. Although commonly considered a terrestrial genus, and most abundantly found in soil, Streptomyces strains are found that have distinct requirements for seawater and routinely do not show significant similarity, with terrestrial strains by 16S ribosomal DNA phylogenetic sequence comparisons. Our examination of the culture broth of a Streptomyces sp., strain CNP975, isolated from a local La Jolla, California sediment sample, resulted in the isolation of actinoquinolines A and B (1, 2), which show significant inhibition of the arachidonic acid pathway enzymes cyclooxygenases-1 and -2. The new compounds contain the 3-hydroxyquinaldic acid (3HQA) motif found in numerous peptide antibiotics. In the actinoquinolines, 3HQA forms an amide linkage with a linear six-carbon fragment, formally a 2, 6-diamino-1, 5-dihydroxyhexane unit, a component of likely amino acid reductive off-loading origin. Actinoquinoline A illustrated amide rotational isomerism leading to complex NMR spectral data. Actinoquinoline B was assigned as the C-13 aldehyde analog isolated as an intramolecular hemiacetal. Reduction of 2 with NaBH4 yielded actinoquinoline A thus confirming the relative configurations of all centers in the actinoquinolines. PMID:27220408

  17. Strain gauge installation tool

    DOEpatents

    Conard, Lisa Marie

    1998-01-01

    A tool and a method for attaching a strain gauge to a test specimen by maaining alignment of, and applying pressure to, the strain gauge during the bonding of the gauge to the specimen. The tool comprises rigid and compliant pads attached to a spring-loaded clamp. The pads are shaped to conform to the specimen surface to which the gauge is to be bonded. The shape of the pads permits the tool to align itself to the specimen and to maintain alignment of the gauge to the specimen during the bond curing process. A simplified method of attaching a strain gauge is provided by use of the tool.

  18. Mechanochromic polyurethane strain sensor

    NASA Astrophysics Data System (ADS)

    Cellini, F.; Khapli, S.; Peterson, S. D.; Porfiri, M.

    2014-08-01

    In this Letter, we study the mechanical and optical response of a thermoplastic polyurethane blended with 0.5 wt. % of bis(benzoxazolyl)stilbene dye. The mechanochromic behavior of the material is characterized in a uniaxial stress-relaxation test by simultaneously acquiring the applied force, mechanical deformation, and fluorescence emission. To offer insight into the stress-strain response of the polymer-dye blend, we adapt a classical nonlinear constitutive behavior for elastomeric materials that accounts for stress-induced softening. We correlate the fluorescent response with the mechanical strain to demonstrate the possibility of accurate strain sensing for a broad range of deformations during both loading and unloading.

  19. Strain gauge installation tool

    SciTech Connect

    Conard, Lisa Marie

    1997-12-01

    A tool and a method for attaching a strain gauge to a test specimen by maintaining alignment of, and applying pressure to, the strain gauge during the bonding of the gauge to the specimen. The tool comprises rigid and compliant pads attached to a spring-loaded clamp. The pads are shaped to conform to the specimen surface to which the gauge is to be bonded. The shape of the pads permits the tool to align itself to the specimen and to maintain alignment of the gauge to the specimen during the bond curing process. A simplified method of attaching a strain gauge is provided by use of the tool.

  20. Thin film strain gage development program

    NASA Technical Reports Server (NTRS)

    Grant, H. P.; Przybyszewski, J. S.; Anderson, W. L.; Claing, R. G.

    1983-01-01

    Sputtered thin-film dynamic strain gages of 2 millimeter (0.08 in) gage length and 10 micrometer (0.0004 in) thickness were fabricated on turbojet engine blades and tested in a simulated compressor environment. Four designs were developed, two for service to 600 K (600 F) and two for service to 900 K (1200 F). The program included a detailed study of guidelines for formulating strain-gage alloys to achieve superior dynamic and static gage performance. The tests included gage factor, fatigue, temperature cycling, spin to 100,000 G, and erosion. Since the installations are 30 times thinner than conventional wire strain gage installations, and any alteration of the aerodynamic, thermal, or structural performance of the blade is correspondingly reduced, dynamic strain measurement accuracy higher than that attained with conventional gages is expected. The low profile and good adherence of the thin film elements is expected to result in improved durability over conventional gage elements in engine tests.

  1. Heat strain during explosive ordnance disposal.

    PubMed

    Stewart, Ian B; Rojek, Amanda M; Hunt, Andrew P

    2011-08-01

    Bomb technicians perform their work while encapsulated in explosive ordnance disposal suits. Designed primarily for safety, these suits have an unintended consequence of impairing the body's natural mechanisms for heat dissipation. Consequently, bomb technicians are known to experience symptoms of heat illness while performing their work. This research provides the first field based analysis of heat strain in bomb technicians. Six participants undertook simulated operational tasks across 2 days of variable climate. All subjects demonstrated high levels of heat strain as evidenced by elevated heart rate, core body temperature, and physiological strain index. Participants also reported signs and symptoms associated with heat illness. These results were exacerbated by more intense physical activity despite being undertaken in a cooler environment. The universal experience of heat strain in this sample has significant implications for the health of bomb technicians and additional research examining methods to improve temperature regulation and performance is warranted. PMID:21882791

  2. What Are Sprains and Strains?

    MedlinePlus

    ... sprain, one or more ligaments is stretched or torn. What Causes a Sprain? Where Do Sprains Usually ... strain, a muscle or tendon is stretched or torn. What Causes Strains? A strain is caused by ...

  3. Nanowires enabling strained photovoltaics

    SciTech Connect

    Greil, J.; Bertagnolli, E.; Lugstein, A.; Birner, S.

    2014-04-21

    Photovoltaic nano-devices have largely been relying on charge separation in conventional p-n junctions. Junction formation via doping, however, imposes major challenges in process control. Here, we report on a concept for photovoltaic energy conversion at the nano scale without the need for intentional doping. Our approach relies on charge carrier separation in inhomogeneously strained germanium nanowires (Ge NWs). This concept utilizes the strain-induced gradient in bandgap along tapered NWs. Experimental data confirms the feasibility of strain-induced charge separation in individual vapor-liquid-solid grown Ge NW devices with an internal quantum efficiency of ∼5%. The charge separation mechanism, though, is not inherently limited to a distinct material. Our work establishes a class of photovoltaic nano-devices with its opto-electronic properties engineered by size, shape, and applied strain.

  4. Flexible Bond Wire Capacitive Strain Sensor for Vehicle Tyres.

    PubMed

    Cao, Siyang; Pyatt, Simon; Anthony, Carl J; Kubba, Ammar I; Kubba, Ali E; Olatunbosun, Oluremi

    2016-01-01

    The safety of the driving experience and manoeuvrability of a vehicle can be improved by detecting the strain in tyres. To measure strain accurately in rubber, the strain sensor needs to be flexible so that it does not deform the medium that it is measuring. In this work, a novel flexible bond wire capacitive strain sensor for measuring the strain in tyres is developed, fabricated and calibrated. An array of 25 micron diameter wire bonds in an approximately 8 mm × 8 mm area is built to create an interdigitated structure, which consists of 50 wire loops resulting in 49 capacitor pairs in parallel. Laser machining was used to pattern copper on a flexible printed circuit board PCB to make the bond pads for the wire attachment. The wire array was finally packaged and embedded in polydimethylsiloxane (PDMS), which acts as the structural material that is strained. The capacitance of the device is in a linear like relationship with respect to the strain, which can measure the strain up to at least ±60,000 micro-strain (±6%) with a resolution of ~132 micro-strain (0.013%). In-tyre testing under static loading has shown the ability of the sensor to measure large tyre strains. The technology used for sensor fabrication lends itself to mass production and so the design is considered to be consistent with low cost commercialisable strain sensing technology. PMID:27338402

  5. Flexible Bond Wire Capacitive Strain Sensor for Vehicle Tyres

    PubMed Central

    Cao, Siyang; Pyatt, Simon; Anthony, Carl J.; Kubba, Ammar I.; Kubba, Ali E.; Olatunbosun, Oluremi

    2016-01-01

    The safety of the driving experience and manoeuvrability of a vehicle can be improved by detecting the strain in tyres. To measure strain accurately in rubber, the strain sensor needs to be flexible so that it does not deform the medium that it is measuring. In this work, a novel flexible bond wire capacitive strain sensor for measuring the strain in tyres is developed, fabricated and calibrated. An array of 25 micron diameter wire bonds in an approximately 8 mm × 8 mm area is built to create an interdigitated structure, which consists of 50 wire loops resulting in 49 capacitor pairs in parallel. Laser machining was used to pattern copper on a flexible printed circuit board PCB to make the bond pads for the wire attachment. The wire array was finally packaged and embedded in polydimethylsiloxane (PDMS), which acts as the structural material that is strained. The capacitance of the device is in a linear like relationship with respect to the strain, which can measure the strain up to at least ±60,000 micro-strain (±6%) with a resolution of ~132 micro-strain (0.013%). In-tyre testing under static loading has shown the ability of the sensor to measure large tyre strains. The technology used for sensor fabrication lends itself to mass production and so the design is considered to be consistent with low cost commercialisable strain sensing technology. PMID:27338402

  6. Test load verification through strain data analysis

    NASA Technical Reports Server (NTRS)

    Verderaime, V.; Harrington, F.

    1995-01-01

    A traditional binding acceptance criterion on polycrystalline structures is the experimental verification of the ultimate factor of safety. At fracture, the induced strain is inelastic and about an order-of-magnitude greater than designed for maximum expected operational limit. At this extreme strained condition, the structure may rotate and displace at the applied verification load such as to unknowingly distort the load transfer into the static test article. Test may result in erroneously accepting a submarginal design or rejecting a reliable one. A technique was developed to identify, monitor, and assess the load transmission error through two back-to-back surface-measured strain data. The technique is programmed for expediency and convenience. Though the method was developed to support affordable aerostructures, the method is also applicable for most high-performance air and surface transportation structural systems.

  7. Strain Engineering to Modify the Electrochemistry of Energy Storage Electrodes

    NASA Astrophysics Data System (ADS)

    Muralidharan, Nitin; Carter, Rachel; Oakes, Landon; Cohn, Adam P.; Pint, Cary L.

    2016-06-01

    Strain engineering has been a critical aspect of device design in semiconductor manufacturing for the past decade, but remains relatively unexplored for other applications, such as energy storage. Using mechanical strain as an input parameter to modulate electrochemical potentials of metal oxides opens new opportunities intersecting fields of electrochemistry and mechanics. Here we demonstrate that less than 0.1% strain on a Ni-Ti-O based metal-oxide formed on superelastic shape memory NiTi alloys leads to anodic and cathodic peak potential shifts by up to ~30 mV in an electrochemical cell. Moreover, using the superelastic properties of NiTi to enable strain recovery also recovers the electrochemical potential of the metal oxide, providing mechanistic evidence of strain-modified electrochemistry. These results indicate that mechanical energy can be coupled with electrochemical systems to efficiently design and optimize a new class of strain-modulated energy storage materials.

  8. Strain Engineering to Modify the Electrochemistry of Energy Storage Electrodes

    PubMed Central

    Muralidharan, Nitin; Carter, Rachel; Oakes, Landon; Cohn, Adam P.; Pint, Cary L.

    2016-01-01

    Strain engineering has been a critical aspect of device design in semiconductor manufacturing for the past decade, but remains relatively unexplored for other applications, such as energy storage. Using mechanical strain as an input parameter to modulate electrochemical potentials of metal oxides opens new opportunities intersecting fields of electrochemistry and mechanics. Here we demonstrate that less than 0.1% strain on a Ni-Ti-O based metal-oxide formed on superelastic shape memory NiTi alloys leads to anodic and cathodic peak potential shifts by up to ~30 mV in an electrochemical cell. Moreover, using the superelastic properties of NiTi to enable strain recovery also recovers the electrochemical potential of the metal oxide, providing mechanistic evidence of strain-modified electrochemistry. These results indicate that mechanical energy can be coupled with electrochemical systems to efficiently design and optimize a new class of strain-modulated energy storage materials. PMID:27283872

  9. Strain Engineering to Modify the Electrochemistry of Energy Storage Electrodes.

    PubMed

    Muralidharan, Nitin; Carter, Rachel; Oakes, Landon; Cohn, Adam P; Pint, Cary L

    2016-01-01

    Strain engineering has been a critical aspect of device design in semiconductor manufacturing for the past decade, but remains relatively unexplored for other applications, such as energy storage. Using mechanical strain as an input parameter to modulate electrochemical potentials of metal oxides opens new opportunities intersecting fields of electrochemistry and mechanics. Here we demonstrate that less than 0.1% strain on a Ni-Ti-O based metal-oxide formed on superelastic shape memory NiTi alloys leads to anodic and cathodic peak potential shifts by up to ~30 mV in an electrochemical cell. Moreover, using the superelastic properties of NiTi to enable strain recovery also recovers the electrochemical potential of the metal oxide, providing mechanistic evidence of strain-modified electrochemistry. These results indicate that mechanical energy can be coupled with electrochemical systems to efficiently design and optimize a new class of strain-modulated energy storage materials. PMID:27283872

  10. Strain Rate Dependence of Compressive Stress-Strain Loops of Several Polymers

    NASA Astrophysics Data System (ADS)

    Nakai, Kenji; Yokoyama, Takashi

    The compressive stress-strain loops of several commercial polymers at strain rates of nearly 700/s are determined in the standard split Hopkinson pressure bar. Four different polymers or typical thermoplastics: ABS, PA-6, PA-66 and PC are tested at room temperature. Cylindrical specimens with a slenderness ratio (= height l /diameter d) of 0.5 are used in the Hopkinson bar tests, and those with l/d = 1.5 as specified in the ASTM Designation E9-89a are used in the static tests. The stress-strain loops in compression at low and intermediate strain rates are measured in an Instron testing machine. The influences of strain rate on the Young's modulus, 2.5% flow stress and dissipation energy are investigated. It is demonstrated that the area within the stress-strain loop (or dissipation energy) increases with increasing strain rate as well as given strain, that is, all polymers tested exhibit intrinsic dynamic viscoelasticity and a high elastic aftereffect following complete unloading.

  11. MEMS Graphene Strain Sensor

    NASA Astrophysics Data System (ADS)

    Young, Clinton Wen-Chieh

    Graphene is a two dimensional honeycomb structure of sp2 hybridized carbon atoms that has possibilities in many applications due to its excellent mechanical and electrical properties. One application for Graphene is in the field of sensors. Graphene's electronic properties do not degrade when it undergoes mechanical strain which is advantageous for strain sensors. In this thesis, certain properties, such as the piezo-resistivity and flexibility, of graphene will be explored to show how they can be utilized to make a strain sensing device. Our original fabrication process of patterning graphene and the transfer process of graphene onto a flexible substrate will be discussed. The development of a stretchable and flexible graphene based rosette strain sensor will also be detailed. Developing a novel, reliable patterning process for the graphene is the first step to manufacture a stretchable graphene based sensor. The graphene was patterned using a photolithography and etching process that was developed by our research team, then it was transferred to a flexible polymer substrate with the use of a combination of soft lithography and wet etching of the Ni foil with ferric chloride solution. Graphene patterning is an essential step in fabricating reliable and sensitive sensors. With this process, graphene can be consistently patterned into different shapes and sizes. To utilize the graphene as the sensing material it also needs to be transferred onto a flexible substrate. The innovative transfer process developed by our research team consistently adheres graphene to a flexible PDMS substrate while removing the original nickel substrate. In the end, the graphene was transferred from the metal substrate to the desired flexible substrate. This process was repeated multiple times to create a stack and multilayer device. While many graphene-based strain sensors have been developed, they are uni-directional and can only measure the strain applied on the sensor in a principle

  12. Characterization of the iron-regulated desA promoter of Streptomyces pilosus as a system for controlled gene expression in actinomycetes

    PubMed Central

    Flores, Francisco J; Rincón, Javier; Martín, Juan F

    2003-01-01

    Background The bioavailability of iron is quite low since it is usually present as insoluble complexes. To solve the bioavailability problem microorganisms have developed highly efficient iron-scavenging systems based on the synthesis of siderophores that have high iron affinity. The systems of iron assimilation in microorganisms are strictly regulated to control the intracellular iron levels since at high concentrations iron is toxic for cells. Streptomyces pilosus synthesizes the siderofore desferrioxamine B. The first step in desferrioxamine biosynthesis is decarboxylation of L-lysine to form cadaverine, a desferrioxamine B precursor. This reaction is catalyzed by the lysine decarboxylase, an enzyme encoded by the desA gene that is repressed by iron. Results The binding of the DmdR (acronym for divalent metal dependent repressor) to the desA promoter in presence of Fe2+ or other divalent ions has been characterized. A 51 bp DNA fragment of the desA promoter containing the 9 bp inverted repeat was sufficient for binding of the DmdR repressor, as observed by the electrophoretic mobility shift assay. The desA mobility shift was prevented by neutralizing DmdR with anti-DmdR antibodies or by chelating the divalent metal in the binding reaction with 2,2'-dipyridyl. Binding to the desA promoter was observed with purified DmdR repressors of Streptomyces coelicolor or Rhodococcus fascians suggesting that there is a common mechanism of iron-regulation in actinomycetes. The complete desA promoter region was coupled using transcriptional fusions to the amy reporter gene (encoding α-amylase) in low copy or multicopy Streptomyces vectors. The iron-regulated desA promoter was induced by addition of the iron chelating agent 2,2'-dipyridyl resulting in a strong expression of the reporter gene. Conclusions The iron-regulated desA promoter can be used for inducible expression of genes in Streptomyces species, as shown by de-repression of the promoter when coupled to a reporter

  13. Metabolomics of the Bio-Degradation Process of Aflatoxin B1 by Actinomycetes at an Initial pH of 6.0

    PubMed Central

    Eshelli, Manal; Harvey, Linda; Edrada-Ebel, RuAngelie; McNeil, Brian

    2015-01-01

    Contamination of food and feed by Aflatoxin B1 (AFB1) is a cause of serious economic and health problems. Different processes have been used to degrade AFB1. In this study, biological degradation of AFB1 was carried out using three Actinomycete species, Rhodococcus erythropolis ATCC 4277, Streptomyces lividans TK 24, and S. aureofaciens ATCC 10762, in liquid cultures. Biodegradation of AFB1 was optimised under a range of temperatures from 25 to 40 °C and pH values of 4.0 to 8.0. An initial concentration of 20 µg/mL of AFB1 was used in this study. The amount of AFB1 remaining was measured against time by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC), coupled with UV and mass spectrometry (LC-MS). All species were able to degrade the AFB1, and no significant difference was found between them. AFB1 remained in the liquid culture for R. erythropolis, S. lividans and S. aureofaciens were 0.81 µg/mL, 2.41 µg/mL and 2.78 µg/mL respectively, at the end of the first 24 h. Degradation occurred at all incubation temperatures and the pH with the optimal conditions for R. erythropolis was achieved at 30 °C and pH 6, whereas for S. lividans and S. aureofaciens the optimum conditions for degradation were 30 °C and pH 5. Analysis of the degradative route indicated that each microorganism has a different way of degrading AFB1. The metabolites produced by R. erythropolis were significantly different from the other two microorganisms. Products of degradation were identified through metabolomic studies by utilizing high-resolution mass spectral data. Mass spectrometric analysis indicated that the degradation of AFB1 was associated with the appearance of a range of lower molecular weight compounds. The pathway of degradation or chemical alteration of AFB1 was followed by means of high resolution Fourier transform mass spectrometry (HR-FTMS) analysis as well as through the MS2 fragmentation to unravel the degradative pathway for AFB1. AFB1 bio

  14. Two exo-β-D-glucosaminidases/exochitosanases from actinomycetes define a new subfamily within family 2 of glycoside hydrolases

    PubMed Central

    Côté, Nathalie; Fleury, Alain; Dumont-Blanchette, Émilie; Fukamizo, Tamo; Mitsutomi, Masaru; Brzezinski, Ryszard

    2005-01-01

    A GlcNase (exo-β-D-glucosaminidase) was purified from culture supernatant of Amycolatopsis orientalis subsp. orientalis grown in medium with chitosan. The enzyme hydrolysed the terminal GlcN (glucosamine) residues in oligomers of GlcN with transglycosylation observed at late reaction stages. 1H-NMR spectroscopy revealed that the enzyme is a retaining glycoside hydrolase. The GlcNase also behaved as an exochitosanase against high-molecular-mass chitosan with Km and kcat values of 0.16 mg/ml and 2832 min−1. On the basis of partial amino acid sequences, PCR primers were designed and used to amplify a DNA fragment which then allowed the cloning of the GlcNase gene (csxA) associated with an open reading frame of 1032 residues. The GlcNase has been classified as a member of glycoside hydrolase family 2 (GH2). Sequence alignments identified a group of CsxA-related protein sequences forming a distinct GH2 subfamily. Most of them have been annotated in databases as putative β-mannosidases. Among these, the SAV1223 protein from Streptomyces avermitilis has been purified following gene cloning and expression in a heterologous host and shown to be a GlcNase with no detectable β-mannosidase activity. In CsxA and all relatives, a serine-aspartate doublet replaces an asparagine residue and a glutamate residue, which were strictly conserved in previously studied GH2 members with β-galactosidase, β-glucuronidase or β-mannosidase activity and shown to be directly involved in various steps of the catalytic mechanism. Alignments of several other GH2 members allowed the identification of yet another putative subfamily, characterized by a novel, serine-glutamate doublet at these positions. PMID:16316314

  15. Fiber-Optic Strain Sensors With Linear Characteristics

    NASA Technical Reports Server (NTRS)

    Egalon, Claudio O.; Rogowski, Robert S.

    1993-01-01

    Fiber-optic modal domain strain sensors having linear characteristics over wide range of strains proposed. Conceived in effort to improve older fiber-optic strain sensors. Linearity obtained by appropriate choice of design parameters. Pattern of light and dark areas at output end of optical fiber produced by interference between electromagnetic modes in which laser beam propagates in fiber. Photodetector monitors intensity at one point in pattern.

  16. Design and evaluation of two-stage multiplex real-time PCR method for detecting O157:H7 and non-O157 STEC strains from beef samples

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: E. coli O157:H7 was first recognized as a human pathogen in 1982 and until recently was the only E. coli strain mandated for testing by the USDA. In June 2012, the USDA declared six additional Shiga-toxin producing E. coli serogroups (O26, O45, O103, O111, O121, and O145) as adulterant...

  17. Isolation and antifungal and antioomycete activities of staurosporine from Streptomyces roseoflavus strain LS-A24.

    PubMed

    Park, Hee Jin; Lee, Jung Yeop; Hwang, In Sun; Yun, Bong Sik; Kim, Beom Seok; Hwang, Byung Kook

    2006-04-19

    The actinomycete strain LS-A24 active against some plant fungal and oomycete pathogens was isolated from a soil sample of the Sunghwan Lake in Korea. The cell wall composition and spore shape of strain LS-A24 were LL-diaminopimelic acid and spiral type, respectively. On the basis of the physiological and biochemical characteristics and 16S ribosomal DNA sequence analysis, strain LS-A24 was identical to Streptomyces roseoflavus. An antifungal and antioomycete antibiotic was isolated from LS-A24 using various chromatographic procedures. The molecular formular of the antibiotic was determined to be C(28)H(26)N(4)O(3), and on the basis of the NMR data, the antibiotic was confirmed to be staurosporine, 2,3,10,11,12,13-hexahydro-10R-methoxy-9S-methyl-11R-methylamino-9S,13R-epoxy-1H,9H-diindolo[1,2,3-gh:3',2',1'-lm]pyrrolo[3,4-j][1,7]benzodiazonin-1-one. Staurosporine completely inhibited the mycelial growth of Colletotrichum orbiculare, Phytophthora capsici, Rhizoctonia solani, Botrytis cinerea, and Cladosporium cucumerinum with minimum inhibitory concentration (MIC) values of 1-50 microg/mL for MICs. Staurosporine also was active against Saccharomyces cerevisiae, Bacillus subtilis ssp. subtilis, and Xanthomonas vesicatoria. Staurosporine and the commercial fungicide metalaxyl inhibited the development of Phytophthora blight on pepper plants. However, the control efficacy of staurosporine against the Phytophthora disease was somewhat less than that of metalaxyl. This is the first study to isolate staurosporine from S. roseoflavus and demonstrate its in vitro and in vivo antioomycete activity against P. capsici. PMID:16608228

  18. Fiber optic strain monitoring for pipelines

    SciTech Connect

    Berthold, J.W.

    1998-04-08

    The objective of this project was to demonstrate the feasibility of using fiber optic Bragg grating sensors (BGS) to measure axial and bending strain in pipes. Work was performed by McDermott Technology Inc. (MTI) and included BGS design and procurement. In addition to the pipe strain testing, a number of BGS evaluations were performed. Several methods were evaluated to protect and encapsulate the BGS, which are embedded inside an optical fiber, and strain transfer tests were performed on two of the encapsulation approaches. A high strain bending test to failure was performed on one BGS. A special test section was used to characterize the performance of the BGS and compare to standard electrical resistance foil strain gages. Two sets of pipe strain tests were performed. In the first test series, optical fiber was positioned along the pipe test section and embedded BGS were attached directly to the outside of the pipe wall. In the second tests series, the BGS were encapsulated inside a stainless steel tube which was attached to the outside of the pipe wall. All the tests were successfully completed, the data analyzed, and the results summarized in this report.

  19. Purification and Characterization of Phosphonoglycans from Glycomyces sp. Strain NRRL B-16210 and Stackebrandtia nassauensis NRRL B-16338

    PubMed Central

    Yu, Xiaomin; Price, Neil P. J.; Evans, Bradley S.

    2014-01-01

    Two related actinomycetes, Glycomyces sp. strain NRRL B-16210 and Stackebrandtia nassauensis NRRL B-16338, were identified as potential phosphonic acid producers by screening for the gene encoding phosphoenolpyruvate (PEP) mutase, which is required for the biosynthesis of most phosphonates. Using a variety of analytical techniques, both strains were subsequently shown to produce phosphonate-containing exopolysaccharides (EPS), also known as phosphonoglycans. The phosphonoglycans were purified by sequential organic solvent extractions, methanol precipitation, and ultrafiltration. The EPS from the Glycomyces strain has a mass of 40 to 50 kDa and is composed of galactose, xylose, and five distinct partially O-methylated galactose residues. Per-deutero-methylation analysis indicated that galactosyl residues in the polysaccharide backbone are 3,4-linked Gal, 2,4-linked 3-MeGal, 2,3-linked Gal, 3,6-linked 2-MeGal, and 4,6-linked 2,3-diMeGal. The EPS from the Stackebrandtia strain is comprised of glucose, galactose, xylose, and four partially O-methylated galactose residues. Isotopic labeling indicated that the O-methyl groups in the Stackebrandtia phosphonoglycan arise from S-adenosylmethionine. The phosphonate moiety in both phosphonoglycans was shown to be 2-hydroxyethylphosphonate (2-HEP) by 31P nuclear magnetic resonance (NMR) and mass spectrometry following strong acid hydrolysis of the purified molecules. Partial acid hydrolysis of the purified EPS from Glycomyces yielded 2-HEP in ester linkage to the O-5 or O-6 position of a hexose and a 2-HEP mono(2,3-dihydroxypropyl)ester. Partial acid hydrolysis of Stackebrandtia EPS also revealed the presence of 2-HEP mono(2,3-dihydroxypropyl)ester. Examination of the genome sequences of the two strains revealed similar pepM-containing gene clusters that are likely to be required for phosphonoglycan synthesis. PMID:24584498

  20. High-Temperature Adhesive Strain Gage Developed

    NASA Technical Reports Server (NTRS)

    Pereira, J. Michael; Roberts, Gary D.

    1997-01-01

    Researchers at the NASA Lewis Research Center have developed a unique strain gage and adhesive system for measuring the mechanical properties of polymers and polymer composites at elevated temperatures. This system overcomes some of the problems encountered in using commercial strain gages and adhesives. For example, typical commercial strain gage adhesives require a postcure at temperatures substantially higher than the maximum test temperature. The exposure of the specimen to this temperature may affect subsequent results, and in some cases may be higher than the glass-transition temperature of the polymer. In addition, although typical commercial strain gages can be used for short times at temperatures up to 370 C, their long-term use is limited to 230 C. This precludes their use for testing some high-temperature polyimides near their maximum temperature capability. Lewis' strain gage and adhesive system consists of a nonencapsulated, unbacked gage grid that is bonded directly to the polymer after the specimen has been cured but prior to the normal postcure cycle. The gage is applied with an adhesive specially formulated to cure under the specimen postcure conditions. Special handling, mounting, and electrical connection procedures were developed, and a fixture was designed to calibrate each strain gage after it was applied to a specimen. A variety of tests was conducted to determine the performance characteristics of the gages at elevated temperatures on PMR-15 neat resin and titanium specimens. For these tests, which included static tension, thermal exposure, and creep tests, the gage and adhesive system performed within normal strain gage specifications at 315 C. An example of the performance characteristics of the gage can be seen in the figure, which compares the strain gage measurement on a polyimide specimen at 315 C with an extensometer measurement.