Phage-encoded sigma factors alter bacterial dormancy
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ABSTRACT:
PROVIDER: PRJNA777257 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR16701000_1.fastq.gz | Fastqsanger.gz | |||
| SRR16701000_2.fastq.gz | Fastqsanger.gz | |||
| SRR16701001_1.fastq.gz | Fastqsanger.gz | |||
| SRR16701001_2.fastq.gz | Fastqsanger.gz | |||
| SRR16701002_1.fastq.gz | Fastqsanger.gz |
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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.
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Project description:By entering a reversible state of reduced metabolic activity, dormant microorganisms are able to tolerate suboptimal conditions that would otherwise reduce their fitness. Dormancy may also benefit bacteria by serving as a refuge from parasitic infections. Here, we focus on dormancy in the Bacillota, where endospore development is transcriptionally regulated by the expression of sigma factors. A disruption of this process could influence the survivorship or reproduction of phages that infect spore-forming hosts with implications for coevolutionary dynamics. We characterized the distribution of sigma factors in over 4,000 genomes of diverse phages capable of infecting hosts that span the bacterial domain. From this, we identified homologs of sporulation-specific sigma factors in phages that infect spore-forming hosts. Unlike sigma factors required for phage reproduction, we provide evidence that sporulation-like sigma factors are nonessential for lytic infection. However, when expressed in the spore-forming Bacillus subtilis, some of these phage-derived sigma factors can activate the bacterial sporulation gene network and lead to a reduction in spore yield. Our findings suggest that the acquisition of host-like transcriptional regulators may allow phages to manipulate a complex and ancient trait in one of the most abundant cell types on Earth. IMPORTANCE As obligate parasites, phages exert strong top-down pressure on host populations with eco-evolutionary implications for community dynamics and ecosystem functioning. The process of phage infection, however, is constrained by bottom-up processes that influence the energetic and nutritional status of susceptible hosts. Many phages have acquired auxiliary genes from bacteria, which can be used to exploit host metabolism with consequences for phage fitness. In this study, we demonstrate that phages infecting spore-forming bacteria carry homologs of sigma factors, which their hosts use to orchestrate gene expression during spore development. By tapping into regulatory gene networks, phages may manipulate the physiology and survival strategies of nongrowing bacteria in ways that influence host-parasite coevolution.
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Project description:Bacteriophages (phages) significantly influence bacterial populations in their natural environment. However, one aspect that has not been thoroughly explored in the context of phage-bacteria interactions is the post-transcriptional regulation of gene expression, despite the growing attention it has received for bacterial physiology over the last two decades. Important players in this process are small RNAs (sRNAs) that regulate target mRNAs via base-pairing, typically using RNA chaperones like Hfq to facilitate this regulation. Here, we apply RIL-seq, to map in-vivo the sRNA-RNA network in Escherichia coli upon lambda phage infection. We highlight changes in the bacterial transcriptome and sRNA interactome while uncovering a novel phage-encoded sRNA that regulates key genes in E. coli. We decipher the molecular mechanism of the sRNA-mediated regulation and illustrate how it hijacks the host replication machinery and helps the infection cycle. Overall, we uncover an RNA-level regulatory layer that shapes the E. coli - lambda interactions.
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Project description:Bacteriophages (phages) significantly influence bacterial populations in their natural environment. However, one aspect that has not been thoroughly explored in the context of phage-bacteria interactions is the post-transcriptional regulation of gene expression, despite the growing attention it has received for bacterial physiology over the last two decades. Important players in this process are small RNAs (sRNAs) that regulate target mRNAs via base-pairing, typically using RNA chaperones like Hfq to facilitate this regulation. Here, we apply RIL-seq, to map in-vivo the sRNA-RNA network in Escherichia coli upon lambda phage infection. We highlight changes in the bacterial transcriptome and sRNA interactome while uncovering a novel phage-encoded sRNA that regulates key genes in E. coli. We decipher the molecular mechanism of the sRNA-mediated regulation and illustrate how it hijacks the host replication machinery and helps the infection cycle. Overall, we uncover an RNA-level regulatory layer that shapes the E. coli - lambda interactions.
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Project description:Transcriptional Regulation and Mechanism of SigN (ZpdN), a pBS32 encoded Sigma Factor
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