Project description:We describe the design and evaluate the use of a high density oligonuclotide microarray covering seven sequenced E. coli genomes in addition to several sequenced E. coli plasmids, bacteriophages, pathogenicity islands and virulence genes. Its utility is demonstrated for comparative genomic profiling of two unsequenced strains, O175:H16 D1 and O157:H7 3538 as well as two well-known control strains, K-12 W3110 and O157:H7 EDL933. By using fluorescently labelled genomic DNA to query the microarrays and subsequently analyse common virulence genes and phage elements, and perform whole genome comparisons, we observed that O175:H16 D1 is a K-12 like strain and confirmed that its phi3538 phage element originated from the E. coli 3538 strain with which it shares a substantial proportion of phage elements. Moreover, a number of genes involved in DNA transfer and recombination was identified in both new strains providing a likely explanation for their capability to transfer phi3538 between them. Analyses of control samples demonstrated that results using our custom designed microarray were representative of the true biology, e.g. by confirming the presence of all known chromosomal phage elements as well as 98.8 and 97.7 percent of queried chromosomal genes for the two control strains. Finally, we demonstrate that use of spatial information, in terms of the physical chromosomal locations of probes, improves the analysis. Keywords: Genomic DNA hybridizations
Project description:In this study differences at the genetic level of 24 S. Enteritidis strains from six phage types were compared using Comparative Genomic Hybridisation (CGH) DNA microarrays to determine why some certain phage types are 'less successful' in causing human infection.
Project description:We used whole bodies of four different adult fire ant morphs (alate queens, workers, haploid males, and diploid males) from a single polygyne colony to generate single-base resolution DNA methylation maps. DNA was extracted from whole bodies of individual males, individual queens, and pooled workers. Bisulfite conversion and sequencing was performed by Beijing Genomics Institute (Shenzhen, China). Unmethylated enterobacteria phage lambda DNA (GenBank accession: J02459.1) was added to each genomic DNA sample as a control for bisulfite conversion efficiency.
Project description:Restriction-modification (R-M) systems protect against phage infection by detecting and degrading invading foreign DNA. However, like many prokaryotic anti-phage defenses, R-M systems pose a significant risk of auto-immunity, exacerbated by the presence of hundreds to thousands of potential cleavage sites in the bacterial genome. Pseudomonas aeruginosa strains experience the temporary inactivation of restriction endonucleases (tiREN) upon growth at high temperatures, but the mechanisms and implications of this are unknown. Here, we report that P. aeruginosa Type I restriction endonuclease (HsdR) is degraded, and the methyltransferase (HsdMS) is partially degraded, by two Lon-like proteases when replicating above 41 °C. This post-translational regulation prevents self-DNA targeting and leads to partial genomic hypomethylation, as demonstrated by SMRT sequencing and eTAM-seq. Interestingly, upon return to 37 ºC, restriction activity and full genomic methylation do not fully recover for up to 60 bacterial generations. Our findings demonstrate that Type I R-M is tightly regulated post-translationally with a long memory effect that ensures genomic stability and mitigates auto-toxicity.
Project description:Genomic material isolated from purified phage YerA41 lysate was shown to contain RNA. YerA41 phage lysate was RNase treated to remove phage-external RNA and total RNA was then isolated from the phage preparate using Qiagen Rneasy mini kit. The isolated RNA was sequenced to elucidate its origin. The results suggested that the RNA originated from intact ribosomes of the host bacterium that contaminated the phage lysate.
2022-04-04 | GSE199969 | GEO
Project description:Genomic DNA sequencing of vB_EcoM-RPN187 phage
| PRJNA1055028 | ENA
Project description:Genomic DNA sequencing of Escherichia phage nasanit
| PRJNA1223920 | ENA
Project description:Genomic DNA sequencing of Escherichia phage nithesis
| PRJNA1223940 | ENA
Project description:Genomic DNA sequencing of vB_EcoM-RPN226 phage
| PRJNA1055045 | ENA
Project description:Genomic DNA sequencing of Escherichia phage kaset