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Activation of the extracytoplasmic function ? factor ?^V by lysozyme.

ABSTRACT: ?^V is an extracytoplasmic function (ECF) ? factor that is found exclusively in Firmicutes including Bacillus subtilis and the opportunistic pathogens Clostridioides difficile and Enterococcus faecalis. ?^V is activated by lysozyme and is required for lysozyme resistance. The activity of ?^V is normally inhibited by the anti-? factor RsiV, a transmembrane protein. RsiV acts as a receptor for lysozyme. The binding of lysozyme to RsiV triggers a signal transduction cascade which results in degradation of RsiV and activation of ?^V . Like the anti-? factors for several other ECF ? factors, RsiV is degraded by a multistep proteolytic cascade that is regulated at the step of site-1 cleavage. Unlike other anti-? factors, site-1 cleavage of RsiV is not dependent upon a site-1 protease whose activity is regulated. Instead constitutively active signal peptidase cleaves RsiV at site-1 in a lysozyme-dependent manner. The activation of ?^V leads to the transcription of genes, which encode proteins required for lysozyme resistance.

SUBMITTER: Ho TD

PROVIDER: S-EPMC6703919 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Activation of the extracytoplasmic function σ factor σV by lysozyme.

Ho Theresa D TD Ellermeier Craig D CD

Molecular microbiology 20190718 2

σV is an extracytoplasmic function (ECF) σ factor that is found exclusively in Firmicutes including Bacillus subtilis and the opportunistic pathogens Clostridioides difficile and Enterococcus faecalis. σV is activated by lysozyme and is required for lysozyme resistance. The activity of σV is normally inhibited by the anti-σ factor RsiV, a transmembrane protein. RsiV acts as a receptor for lysozyme. The binding of lysozyme to RsiV triggers a signal transduction ca ...[more]

PMID: 31286585

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