Bacteria
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ABSTRACT:
PROVIDER: PRJNA511880 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Helicobacter pylori has a very plastic genome, reflecting its high rate of recombination and point mutation. This plasticity promotes divergence of the population by the development of subclones and presumably enhances adaptation to host niches. We have investigated the genotypic and phenotypic characteristics of two such subclones isolated from one patient as well as the genetic evolution of these isolates during experimental infection. Whole-genome genotyping of the isolates using DNA microarrays revealed that they were more similar to each other than to a panel of other genotyped strains recovered from different hosts. Nonetheless, they still showed significant differences. The genomic evolution of both isolates during the infection of conventionally raised and germ-free mice was monitored over the course of 3 months. The Cag PAI-positive isolate was also surveyed after a 10 month colonization of conventionally raised transgenic animals (n = 9 mice). Microarray analysis of the Cag PAI and sequence analysis of the cagA, recA, and 16S rRNA genes disclosed no changes in recovered isolates. Together, these results reveal that the H. pylori population infecting one individual can undergo significant divergence, creating stable subclones with substantial genotypic and phenotypic differences. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Keywords: Logical Set
2005-10-20 | GSE3478 | GEO
Project description:Introduction Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) are increasingly isolated, with USA300-0114 being the predominant clone in the USA. Comparative whole genome sequencing of USA300 isolates collected in 2002, 2003 and 2005 showed a limited number of single nucleotide polymorphisms and regions of difference. This suggests that USA300 has undergone rapid clonal expansion without great genomic diversification. However, whole genome comparison of CA-MRSA has been limited to isolates belonging to USA300. The aim of this study was to compare the genetic repertoire of different CA-MRSA clones with that of HA-MRSA from the USA and Europe through comparative genomic hybridization (CGH) to identify genetic clues that may explain the successful and rapid emergence of CA-MRSA. Materials and Methods Hierarchical clustering based on CGH of 48 MRSA isolates from the community and nosocomial infections from Europe and the USA revealed dispersed clustering of the 19 CA-MRSA isolates. This means that these 19 CA-MRSA isolates do not share a unique genetic make-up. Only the PVL genes were commonly present in all CA-MRSA isolates. However, 10 genes were variably present among 14 USA300 isolates. Most of these genes were present on mobile elements. Conclusion The genetic variation present among the 14 USA300 isolates is remarkable considering the fact that the isolates were recovered within one month and originated from a confined geographic area, suggesting continuous evolution of this clone. Data is also available from <ahref=http://bugs.sgul.ac.uk/E-BUGS-108 target=_blank>BuG@Sbase</a>
2011-04-15 | E-BUGS-108 | biostudies-arrayexpress
Project description:Helicobacter pylori has a very plastic genome, reflecting its high rate of recombination and point mutation. This plasticity promotes divergence of the population by the development of subclones and presumably enhances adaptation to host niches. We have investigated the genotypic and phenotypic characteristics of two such subclones isolated from one patient as well as the genetic evolution of these isolates during experimental infection. Whole-genome genotyping of the isolates using DNA microarrays revealed that they were more similar to each other than to a panel of other genotyped strains recovered from different hosts. Nonetheless, they still showed significant differences. The genomic evolution of both isolates during the infection of conventionally raised and germ-free mice was monitored over the course of 3 months. The Cag PAI-positive isolate was also surveyed after a 10 month colonization of conventionally raised transgenic animals (n = 9 mice). Microarray analysis of the Cag PAI and sequence analysis of the cagA, recA, and 16S rRNA genes disclosed no changes in recovered isolates. Together, these results reveal that the H. pylori population infecting one individual can undergo significant divergence, creating stable subclones with substantial genotypic and phenotypic differences. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Computed
2005-10-20 | E-GEOD-3478 | biostudies-arrayexpress
Project description:Mitigation of N2O-emissions from soils is needed to reduce climate forcing by food production. Inoculating soils with N2O-reducing bacteria would be effective, but costly and impractical as a standalone operation. Here we demonstrate that digestates obtained after biogas production may provide a low-cost and widely applicable solution. Firstly, we show that indigenous N2O-reducing bacteria in digestates grow to high levels during anaerobic enrichment under N2O. Gas kinetics and meta-omic analysis show that the N2O respiring organisms, recovered as metagenome-assembled genomes (MAGs) grow by harvesting fermentation intermediates of the methanogenic consortium. Three digestate-derived denitrifying bacteria were obtained through isolation, one of which matched the recovered MAG of a dominant Dechloromonas-affiliated N2O reducer. While the identified N2O-reducers encoded genes required for a full denitrification pathway and could thus both produce and sequester N2O, their regulatory traits predicted that they act as N2O-sinks in the current system. Secondly, moving towards practical application, we show that these isolates grow by aerobic respiration in digestates, and that fertilization with these enriched digestates reduces N2O emissions. This shows that the ongoing implementation of biogas production in agriculture opens a new avenue for cheap and effective reduction of N2O emissions from food production.
2022-02-16 | PXD023233 | Pride
Project description:Neisseria meningitidis (meningococcus) is usually transmitted via respiratory droplets, whereas its close relative, the gonococcus is sexually transmitted. Invasive meningococcal disease due to isolates of serogroup C increased in Europe and the United States among men who have sex with men (MSM). These isolates were also recovered from cases of urethritis suggesting sexual transmission. Genome sequencing of representative strains revealed that isolates from MSM and urethritis cases belonged to a unique clade within clonal complex11. Proteome analysis showed expression of nitrite reductase by these isolates, enabling anaerobic growth as in gonococci. Invasive isolates from MSM, but not urethritis isolates expressed functional human factor H (hfH) binding protein associated with enhanced survival in transgenic mice expressing hfH, a complement regulatory protein. Our data provide a unique example of meningococcal evolution with adaptation to sexual transmissibility, initially associated with low virulence but with subsequent fHbp-associated invasiveness. Implications for vaccination strategies are discussed.
2016-05-18 | PXD001498 | Pride
Project description:In Candida albicans, Upc2 is a zinc-cluster transcription factor that targets genes including those of the ergosterol biosynthesis pathway. To date there have been three documented UPC2 gain-of-function (GOF) mutations recovered from fluconazole-resistant clinical isolates that contribute to an increase in ERG11 expression and decreased fluconazole susceptibility. In a group of 62 fluconazole-resistant isolates, we found that 47 of these overexpressed ERG11 by at least two-fold over that of an average expression of 3 unrelated fluconazole susceptible strains. Of those 47 isolates, 29 contained a mutation in UPC2, whereas the remaining 18 isolates did not. Of the isolates containing mutations in UPC2, we recovered eight distinct mutations resulting in single putative amino acid substitutions: G648D, G648S, A643T, A643V, Y642F, G304R, A646V and W478C. Seven of these resulted in increased ERG11 expression, increased cellular ergosterol, and decreased susceptibility to fluconazole as compared to the wild-type strain. Genome-wide transcriptional analysis was performed for the four strongest Upc2 amino acid substitutions (A643V, G648D, G648S and Y642F). Genes commonly upregulated in all four mutations included those involved in ergosterol biosynthesis, in oxidoreductase activity, the major facilitator efflux pump encoded by the MDR1 gene, and the uncharacterized ATP binding cassette transporter CDR11. These findings demonstrate that gain-of-function mutations in UPC2 are more prevalent than previously thought among clinical isolates, make a significant contribution to azole antifungal resistance, but do not account for ERG11 overexpression in all such isolates of C. albicans.
2013-01-31 | GSE39201 | GEO
Project description:Comparative genomic of Streptococcus pyogenes isolates recovered from different isolation source
| PRJNA381156 | ENA
Project description:Comaprision of P.falciparum clinical isolates showing Uncomplicated disease with that shwoing complicated disease(Cerebral malaria) The experiment was designed to try and identify differences if any, at the genome level between P.falciparum isolates from patients with uncomplicated malaria vs. patients with complicated malaria (Cerebral malaria). The emphasis was to highlight possible amplifications/deletions in different regions of the parasite genome.
2017-01-06 | GSE77165 | GEO
Project description:Expression of the extensive arsenal of virulence factors by Streptococcus pyogenes are controlled by many regulators, of which covR/S is one of the best characterized and can influence ~15% of the genome. Animal models have established that mutants of CovR/S arise spontaneously in vivo resulting in highly invasive organisms. We analyzed a pharyngeal and a blood isolate of S. pyogenes recovered from the same individual 13 days apart. The two isolates varied in many phenotypic properties including speB production, which were reflected in transcriptome analyses. Pulsed field gel electrophoresis, multilocus sequence typing, and partial sequencing of some key genes failed to show any differences except for an 11-base insert in the covS gene in the blood isolate. These results showing that pharyngeal and blood isolates from a single individual which differ by a simple insertion, provide evidence for the model that regulatory gene mutations allow S. pyogenes to invade different niches in the body.
2010-05-01 | GSE21316 | GEO