Phage-encoded sigma factors alter bacterial dormancy

Schwartz, D. A.; Lehmkuhl, B. K.; Lennon, J. T.

doi:10.1101/2021.11.12.468384

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bioRxiv · 10.1101/2021.11.12.468384

Phage-encoded sigma factors alter bacterial dormancy

Schwartz, D. A.·Lehmkuhl, B. K.·Lennon, J. T.

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Abstract

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 Firmicutes, where endospore development is transcriptionally regulated by the expression of sigma factors. A disruption of this process could influence the survivorship and reproduction of phages that infect spore-forming hosts with implications for coevolutionary dynamics. Here, we characterized the distribution and diversity of sigma factors in nearly 3,500 phage genomes. Homologs of sporulation-specific sigma factors were identified in phages that infect spore-forming hosts. Unlike sigma factors required for phage reproduction, the sporulation-like sigma factors were non-essential for lytic infection. However, when expressed in the spore-forming Bacillus subtilis, sigma factors from phages activated the bacterial sporulation gene network and reduced 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.

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Schwartz, D. A., Lehmkuhl, B. K., Lennon, J. T.. 2021-11-12. Phage-encoded sigma factors alter bacterial dormancy. https://doi.org/10.1101/2021.11.12.468384

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