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排序方式: 共有1500条查询结果,搜索用时 31 毫秒
891.
Vishnivetskaya TA Lucas S Copeland A Lapidus A Glavina del Rio T Dalin E Tice H Bruce DC Goodwin LA Pitluck S Saunders E Brettin T Detter C Han C Larimer F Land ML Hauser LJ Kyrpides NC Ovchinnikova G Kathariou S Ramaley RF Rodrigues DF Hendrix C Richardson P Tiedje JM 《Journal of bacteriology》2011,193(11):2880-2881
Here we present the genome of strain Exiguobacterium sp. AT1b, a thermophilic member of the genus Exiguobacterium whose representatives were isolated from various environments along a thermal and physicochemical gradient. This genome was sequenced to be a comparative resource for the study of thermal adaptation with a psychroactive representative of the genus, Exiguobacterium sibiricum strain 255-15, that was previously sequenced by the U.S. Department of Energy's (DOE's) Joint Genome Institute (JGI) (http://genome.ornl.gov/microbial/exig/). 相似文献
892.
van Passel MW Kant R Palva A Lucas S Copeland A Lapidus A Glavina del Rio T Dalin E Tice H Bruce D Goodwin L Pitluck S Davenport KW Sims D Brettin TS Detter JC Han S Larimer FW Land ML Hauser L Kyrpides N Ovchinnikova G Richardson PP de Vos WM Smidt H Zoetendal EG 《Journal of bacteriology》2011,193(9):2373-2374
Victivallis vadensis ATCC BAA-548 represents the first cultured representative from the novel phylum Lentisphaerae, a deep-branching bacterial lineage. Few cultured bacteria from this phylum are known, and V. vadensis therefore represents an important organism for evolutionary studies. V. vadensis is a strictly anaerobic sugar-fermenting isolate from the human gastrointestinal tract. 相似文献
893.
The ascomycete fungus Mycosphaerella graminicola is an important pathogen of wheat that causes Septoria tritici blotch. Despite the serious impact of M. graminicola on wheat production worldwide, knowledge about its molecular biology is limited. The velvet gene, veA, is one of the key regulators of diverse cellular processes, including development and secondary metabolism in many fungi. However, the species analyzed to date are not related to the Dothideomycetes, the largest class of plant-pathogenic fungi, and the function of veA in this group is not known. To test the hypothesis that the velvet gene has similar functions in the Dothideomycetes, a veA-homologous gene, MVE1, was identified and gene deletion mutations (Δmve1) were generated in M. graminicola. All of the MVE1 mutants exhibited consistent pleiotropic phenotypes, indicating the involvement of MVE1 in multiple signaling pathways. Δmve1 strains displayed albino phenotypes with significant reductions in melanin biosynthesis and less production of aerial mycelia on agar plates. In liquid culture, Δmve1 strains showed abnormal hyphal swelling, which was suppressed completely by osmotic stress or lower temperature. In addition, MVE1 gene deletion led to hypersensitivity to shaking, reduced hydrophobicity, and blindness to light-dependent stimulation of aerial mycelium production. However, pathogenicity was not altered in Δmve1 strains. Therefore, the light-signaling pathway associated with MVE1 does not appear to be important for Septoria tritici blotch disease. Our data suggest that the MVE1 gene plays crucial roles in multiple key signaling pathways and is associated with light signaling in M. graminicola. 相似文献
894.
Arbuckle W Baker J Barn D Bingham M Brown A Buchanan K Craighead M Goodwin R Goutcher S Kiczun M Lyons A Milne R Montgomery B Napier S Presland J Sloan H Turnbull Z Wishart G 《Bioorganic & medicinal chemistry letters》2011,21(15):4622-4628
The previously described lead compound 5 is a potent and selective V1A antagonist with affinity at both the rat and human receptor, but displays poor oral bioavailability and moderate clearance. We report herein the successful optimisation of the pharmacokinetic (PK) properties to afford the potent, selective, orally bioavailable and CNS penetrant compound 15f. A custom optimisation approach was required which demonstrated the value of using early, rapid in vivo PK studies to show improvements in oral exposure. Such assays may be of particular value where low oral bioavailability is anticipated to be multifactorial (e.g., permeability, gut wall metabolism and/or transport) where satisfactory modelling of in vitro data is likely to be difficult within a drug discovery context. 相似文献
895.
In Sinorhizobium meliloti, catabolite repression is influenced by a noncanonical nitrogen-type phosphotransferase system (PTSNtr). In this PTSNtr, the protein HPr is phosphorylated on histidine-22 by the enzyme EINtr and the flux of phosphate through this residue onto downstream proteins leads to an increase in succinate-mediated catabolite repression (SMCR). In order to explore the molecular determinants of HPr phosphorylation by EINtr, both proteins were purified and the activity of EINtr was measured. Experimentally determined kinetic parameters of EINtr activity were significantly slower than those determined for the carbohydrate-type EI in Escherichia coli. Enzymatic assays showed that glutamine, a signal of nitrogen availability in many Gram-negative bacteria, strongly inhibits EINtr. Binding experiments using the isolated GAF domain of EINtr (EIGAF) showed that it is the domain responsible for detection of glutamine. EINtr activity was not affected by α-ketoglutarate, and no binding between the EIGAF and α-ketoglutarate could be detected. These data suggest that in S. melilloti, EINtr phosphorylation of HPr is regulated by signals from both carbon metabolism (phosphoenolpyruvate) and nitrogen metabolism (glutamine). 相似文献
896.
Paul R McAdam Charles W Vander Broek Diane SJ Lindsay Melissa J Ward Mary F Hanson Michael Gillies Mick Watson Joanne M Stevens Giles F Edwards J Ross Fitzgerald 《Genome biology》2014,15(11)
Background
Legionnaires’ disease is a severe form of pneumonia caused by the environmental bacterium Legionella pneumophila. Outbreaks commonly affect people with known risk factors, but the genetic and pathogenic complexity of L. pneumophila within an outbreak is not well understood. Here, we investigate the etiology of the major Legionnaires’ disease outbreak that occurred in Edinburgh, UK, in 2012, by examining the evolutionary history, genome content, and virulence of L. pneumophila clinical isolates.Results
Our high resolution genomic approach reveals that the outbreak was caused by multiple genetic subtypes of L. pneumophila, the majority of which had diversified from a single progenitor through mutation, recombination, and horizontal gene transfer within an environmental reservoir prior to release. In addition, we discover that some patients were infected with multiple L. pneumophila subtypes, a finding which can affect the certainty of source attribution. Importantly, variation in the complement of type IV secretion systems encoded by different genetic subtypes correlates with virulence in a Galleria mellonella model of infection, revealing variation in pathogenic potential among the outbreak source population of L. pneumophila.Conclusions
Taken together, our study indicates previously cryptic levels of pathogen heterogeneity within a Legionnaires’ disease outbreak, a discovery that impacts on source attribution for future outbreak investigations. Furthermore, our data suggest that in addition to host immune status, pathogen diversity may be an important influence on the clinical outcome of individual outbreak infections.Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0504-1) contains supplementary material, which is available to authorized users. 相似文献897.
David A. C. Beck Tami L. McTaggart Usanisa Setboonsarng Alexey Vorobev Marina G. Kalyuzhnaya Natalia Ivanova Lynne Goodwin Tanja Woyke Mary E. Lidstrom Ludmila Chistoserdova 《PloS one》2014,9(7)
We describe five novel Methylophilaceae ecotypes from a single ecological niche in Lake Washington, USA, and compare them to three previously described ecotypes, in terms of their phenotype and genome sequence divergence. Two of the ecotypes appear to represent novel genera within the Methylophilaceae. Genome-based metabolic reconstruction highlights metabolic versatility of Methylophilaceae with respect to methylotrophy and nitrogen metabolism, different ecotypes possessing different combinations of primary substrate oxidation systems (MxaFI-type methanol dehydrogenase versus XoxF-type methanol dehydrogenase; methylamine dehydrogenase versus N-methylglutamate pathway) and different potentials for denitrification (assimilatory versus respiratory nitrate reduction). By comparing pairs of closely related genomes, we uncover that site-specific recombination is the main means of genomic evolution and strain divergence, including lateral transfers of genes from both closely- and distantly related taxa. The new ecotypes and the new genomes contribute significantly to our understanding of the extent of genomic and metabolic diversity among organisms of the same family inhabiting the same ecological niche. These organisms also provide novel experimental models for studying the complexity and the function of the microbial communities active in methylotrophy. 相似文献
898.
Suman R. Rawat Minna K. M?nnist? Valentin Starovoytov Lynne Goodwin Matt Nolan Loren Hauser Miriam Land Karen Walston Davenport Tanja Woyke Max M. H?ggblom 《Standards in genomic sciences》2014,9(3):449-461
Granulicella tundricola strain MP5ACTX9T is a novel species of the genus Granulicella in subdivision 1 Acidobacteria. G. tundricola is a predominant member of soil bacterial communities, active at low temperatures and nutrient limiting conditions in Arctic alpine tundra. The organism is a cold-adapted acidophile and a versatile heterotroph that hydrolyzes a suite of sugars and complex polysaccharides. Genome analysis revealed metabolic versatility with genes involved in metabolism and transport of carbohydrates, including gene modules encoding for the carbohydrate-active enzyme (CAZy) families for the breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides such as plant based carbon polymers. The genome of G. tundricola strain MP5ACTX9T consists of 4,309,151 bp of a circular chromosome and five mega plasmids with a total genome content of 5,503,984 bp. The genome comprises 4,705 protein-coding genes and 52 RNA genes. 相似文献
899.
Kemanthi Nandasena Ron Yates Ravi Tiwari Graham O’Hara John Howieson Mohamed Ninawi Olga Chertkov Chris Detter Roxanne Tapia Shunseng Han Tanja Woyke Sam Pitluck Matt Nolan Miriam Land Konstantinos Liolios Amrita Pati Alex Copeland Nikos Kyrpides Natalia Ivanova Lynne Goodwin Uma Meenakshi Wayne Reeve 《Standards in genomic sciences》2014,9(3):462-472
Mesorhizobium ciceri bv. biserrulae strain WSM1271T was isolated from root nodules of the pasture legume Biserrula pelecinus growing in the Mediterranean basin. Previous studies have shown this aerobic, motile, Gram negative, non-spore-forming rod preferably nodulates B. pelecinus – a legume with many beneficial agronomic attributes for sustainable agriculture in Australia. We describe the genome of Mesorhizobium ciceri bv. biserrulae strain WSM1271T consisting of a 6,264,489 bp chromosome and a 425,539 bp plasmid that together encode 6,470 protein-coding genes and 61 RNA-only encoding genes. 相似文献
900.
Sven Breider Hazuki Teshima J?rn Petersen Olga Chertkov Hajnalka Dalingault Amy Chen Amrita Pati Natalia Ivanova Alla Lapidus Lynne A. Goodwin Patrick Chain John C. Detter Manfred Rohde Brian J. Tindall Nikos C. Kyrpides Tanja Woyke Meinhard Simon Markus G?ker Hans-Peter Klenk Thorsten Brinkhoff 《Standards in genomic sciences》2014,9(3):687-703