Project description:Multiple infection sources for enterohemorrhagic Escherichia coli O157:H7 are known, including food of animal origin and produce. The ecology of this pathogen outside its human host is largely unknown. One third of its annotated genes still are hypothetical. To identify genetic determinants expressed under environmental factors, we applied strand-specific RNA-sequencing of strain E. coli EDL933 under 11 different biotic and abiotic conditions: LB medium at pH4, pH7, pH9, or at 15°C; LB with nitrite or trimethoprim-sulfamethoxazole; LB-agar surface, M9 minimal medium, spinach leaf juice, surface of living radish sprouts, and cattle feces. Of 5379 annotated genes, only 144 are transcriptionally completely inactive under all conditions. Of 1,771 hypothetical genes, 1,672 exhibit significant transcriptional signals under at least one condition. The pathogenicity island LEE showed highest transcriptional activity in LB medium, minimal medium, and after treatment with antibiotics. Unique sets of genes, including many hypothetical genes, are highly up regulated on radish sprouts, cattle feces, or in the presence of antibiotics. For instance, azoR is biotechnologically important, but its environmental function has been elusive. This gene is highly active on radish sprouts. Further, we observed induction of the shiga-toxin carrying phages by antibiotics and confirmed active biofilm related genes on radish sprouts, in cattle feces, and on agar plates. Thus, environmental transcriptomics uncovers hitherto unknown gene functions and regulatory patterns of Escherichia coli O157:H7.
Project description:Multiple infection sources for enterohemorrhagic Escherichia coli O157:H7 are known, including food of animal origin and produce. The ecology of this pathogen outside its human host is largely unknown. One third of its annotated genes still are hypothetical. To identify genetic determinants expressed under environmental factors, we applied strand-specific RNA-sequencing of strain E. coli EDL933 under 11 different biotic and abiotic conditions: LB medium at pH4, pH7, pH9, or at 15°C; LB with nitrite or trimethoprim-sulfamethoxazole; LB-agar surface, M9 minimal medium, spinach leaf juice, surface of living radish sprouts, and cattle feces. Of 5379 annotated genes, only 144 are transcriptionally completely inactive under all conditions. Of 1,771 hypothetical genes, 1,672 exhibit significant transcriptional signals under at least one condition. The pathogenicity island LEE showed highest transcriptional activity in LB medium, minimal medium, and after treatment with antibiotics. Unique sets of genes, including many hypothetical genes, are highly up regulated on radish sprouts, cattle feces, or in the presence of antibiotics. For instance, azoR is biotechnologically important, but its environmental function has been elusive. This gene is highly active on radish sprouts. Further, we observed induction of the shiga-toxin carrying phages by antibiotics and confirmed active biofilm related genes on radish sprouts, in cattle feces, and on agar plates. Thus, environmental transcriptomics uncovers hitherto unknown gene functions and regulatory patterns of Escherichia coli O157:H7. Eleven different conditions were sequenced on the SOLiD system. Of two of the condtions, spinach medium and LB-nitrite, technical replicates were sequenced. Of LB medium and radish sprouts, biological replicates were sequenced on an Illumina MiSeq.
Project description:Cattle shedding > 10e4 CFU of Escherichia coli O157 per g of feces are defined as super-shedders. RNA-sequencing was performed to identify the transcriptome of tissues, including duodenum, proximal jejunum, distal jejunum, distal jejunum, cecum, spiral colon and descending colon of super-shedder cattle in comparison with non-shedders. The total number of genes detected in gut tissues ranged from 16,846 ± 639 (cecum) to 18,137 ± 696 (distal jejunum), and immune functions were enriched for the transcriptomes of small intestinal tissues, reflecting their greater immune activity than large intestine. Totally 351 differentially expression genes were identified between super-shedders and non-shedders, including 101 up-regulated and 250 down-regulated in super-shedders. Differential gene expression analysis suggested increased T-cell responses and cholesterol absorption in distal jejunum and descending colon, and inhibited B-cell maturation in intestines of super-shedders. distal jejunum of super-shedders. Our findings suggested that host genetics and E. coli O157 activities are involved in super-shedding phenomenon.
2017-08-21 | GSE85277 | GEO
Project description:ESBL producing Escherichia coli from cattle Feces
Project description:We report identification and characterization of antibiotic persister mutants carrying characteristic mutations in the Escherichia coli rpoB gene
2021-01-26 | GSE165446 | GEO
Project description:E. coli with blaCTX-M-15 and blaCTX-M-27 carrying plasmids
Project description:Oligonucleotide DNA microarrays were used as a platform to compare C. jejuni isolates from feedlot cattle and human clinical cases from Alberta. Comparative genomic hybridization (CGH) analysis was performed on 87 isolates (46 bovine, 41 human) obtained within the same geographical regions and time frame. In addition, We also performed gene association analysis to determine if any genes may be differentially distributed between human and cattle sources or between clusters dominated by either human or cattle isolates (“human enriched” vs “cattle enriched”). Keywords: Comparative Genomic Hybridization; Genomic epidemiology; Gene-association study