Similar Datasets
Project description:We used microarray analysis to investigate whole genome transcriptome dynamics of the marine cyanobacterium Prochlorococcus sp. strain MED4 and the T7-like podovirus P-SSP7 over a time course during the 8 hour latent period of lytic infection prior to cell lysis. Manuscript Summary: Interactions between bacterial hosts and their viruses (phages) lead to reciprocal genome evolution through a dynamic co-evolutionary process1-5. Phage-mediated transfer of host genes – often located in genome islands – has had a major impact on microbial evolution1, 4, 6. Furthermore, phage genomes have clearly been shaped by the acquisition of genes from their hosts2, 3, 5. Here we investigate whole-genome expression of a host and phage, the marine cyanobacterium Prochlorococcus and a T7-like cyanophage during lytic infection, to gain insight into these co-evolutionary processes. While most of the phage genome was linearly transcribed over the course of infection, 4 phage-encoded bacterial metabolism genes were part of the same expression cluster, even though they are physically separated on the genome. These genes — encoding photosystem II D1 (psbA), high-light inducible protein (hli), transaldolase (talC) and ribonucleotide reductase (nrd) — are transcribed together with phage DNA replication genes and appear to make up a functional unit involved in energy and deoxynucleotide production needed for phage replication in resource-poor oceans. Also unique to this system was the upregulation of numerous genes in the host during infection. These may be host stress response genes, and/or genes induced by the phage. Many of these host genes are located in genome islands and have homologues in cyanophage genomes. We hypothesize that phage have evolved to utilize upregulated host genes, leading to their stable incorporation into phage genomes and their subsequent transfer back to hosts in genome islands. Thus activation of host genes during infection may be directing the co-evolution of gene content in both host and phage genomes. Keywords: time course, viral infection, marine cyanobacteria, podovirus, bacteriophage, stress response
2007-09-07 | GSE8382 | GEO
Project description:Bacteriophages (phages) are widespread in Streptococcus pneumoniae, with most strains carrying phage genomes integrated into the chromosome. RNA sequencing was utilised to explore whether phage gene expression could be detected. The pneumococcal reference strain PMEN3 (Spain9V-3), which contained two full-length phages and one partial phage, was grown in broth culture and mitomycin C was added to facilitate phage induction. PMEN3 culture samples were taken at sequential time points and RNA was extracted and sequenced.
2017-02-20 | GSE89200 | GEO
Project description:Whole-genome sequencing is an important way to understand the genetic information, gene function, biological characteristics, and living mechanisms of organisms. There is no difficulty to have mega-level genomes sequenced at present. However, we encountered a hard-to-sequence genome of Pseudomonas aeruginosa phage PaP1. The shotgun sequencing method failed to dissect this genome. After insisting for 10 years and going over 3 generations of sequencing techniques, we successfully dissected the PaP1 genome with 91,715 bp in length. Single-molecule sequencing revealed that this genome contains lots of modified bases, including 51 N6-methyladenines (m6A) and 152 N4-methylcytosines (m4C). At the same time, further investigations revealed a novel immune mechanism of bacteria, by which the host bacteria can recognize and repel the modified bases containing inserts in large scale, and this led to the failure of the shotgun method in PaP1 genome sequencing. Strategy of resolving this problem is use of non-library dependent sequencing techniques or use of the nfi- mutant of E. coli DH5M-NM-1 as the host bacteria to construct the shotgun library. In conclusion, we unlock the mystery of phage PaP1 genome hard to be sequenced, and discover a new mechanism of bacterial immunity in present study. Methylation profiling of Pseudomonas aeruginosa phage PaP1 using kinetic data generated by single-molecule, real-time (SMRT) sequencing on the PacBio RS.
2013-08-22 | E-GEOD-50100 | biostudies-arrayexpress
Project description:Provided herein is the first evidence that mycobacteriophage, indeed phage of any kind, have surface proteins (capsid and/or tail tube proteins) that are O-glycosylated. The glycosyltranferases that glycosylate these proteins are encoded in the phage genomes. In addition, for the three mycobacteriophages invested in this study, the glycans appear to be attached exclusively at a C-terminal serine residue. Each phage expresses a unique and novel O-glycan. The LC-MS files deposited here are the preliminary evidence that these mycobacteriophage proteins are glycosylated. A follow-up investigation will examine the composition and structure of the O-glycans in more detail.
2024-08-10 | PXD041690 | Pride
Project description:By entering a reversible state of reduced metabolic activity, dormant microorganisms are able to contend with suboptimal conditions that would otherwise reduce their fitness. In addition, certain types of dormancy like sporulation, can serve as a refuge from parasitic infections. Phages are unable to attach to spores, but their genomes can be entrapped in the resting structures and are able to resume infection upon host germination. Thus, dormancy has the potential to affect both the reproductive and survival components of phage fitness. Here, we characterized the distribution and diversity of sigma factors in nearly 3,500 phage genomes. Homologs of bacterial sigma factors that are responsible for directing transcription during sporulation were preferentially recovered in phages that infect spore-forming hosts. While non-essential for lytic infection, when expressed in Bacillus subtilis, we demonstrate that phage-encoded sigma factors activated sporulation gene networks and reduced spore yield. Our findings suggest that the acquisition of host-like transcriptional regulators may allow phages to manipulate the expression of complex traits, like the transitions involved in bacterial dormancy.
2021-11-05 | GSE187004 | GEO
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
2006-08-29 | GSE4690 | GEO
Project description:ϕXacN1 is a novel jumbo myovirus infecting the causative agent of Asian citrus canker, Xanthomonas citri. Its linear 384,670 bp double-stranded DNA genome encodes 592 predicted protein coding genes and shows 65,875 bp direct terminal repeats (DTRs), so far the longest DTRs among sequence phage genomes. The DTRs harbor 56 tRNA genes, corresponding to all 20 amino acids. This is the highest number of tRNA genes reported in a phage genome. Codon usage analyses revealed a propensity that the phage encoded tRNAs target codons that are highly used by the phage but less frequently by its host. The existence of these tRNA genes, additional seven translation-related genes as well as a chaperonin gene found in the ϕXacN1 genome suggests an increased level of independence of phage replication on host molecular machinery and a wide host range. Consistently, ϕXacN1 showed a wider host range than other X. citri phages in an infection test against a panel of X. citri strains. Phylogenetic analyses revealed a clade of phages composed of ϕXacN1 and ten other jumbo phages showing an evolutionary stability in their large genome sizes.
2018-10-30 | PXD008065 | JPOST Repository
Project description:We designed a pan-Microbial Detection Array (MDA) to detect all known viruses (including phage), bacteria, and plasmids. Family-specific probes were selected for all sequenced viral and bacterial complete genomes, segments, and plasmids. Probes were designed to tolerate some sequence variation to enable detection of divergent species with homology to sequenced organisms. The array has wider coverage of bacterial and viral targets based on more recent sequence data and more probes per target than other microbial detection/discovery arrays in the literature. In blinded lab testing on spiked samples with single or multiple viruses, the MDA was able to correctly identify species or strains. In clinical fecal, serum, and respiratory samples, the MDA was able to detect and characterize multiple viruses, phage, and bacteria in a sample to the family and species level, as confirmed by PCR. Testing of microbial detection array with mixtures of known viruses, blinded clinical samples and viral cell culture samples.
2010-10-15 | E-GEOD-24626 | biostudies-arrayexpress