The activity of σv;, an extracytoplasmic function σ factor of bacillus subtilis, is controlled by regulated proteolysis of the anti-σ factor rsiv

Jessica L. Hastie, Kyle B. Williams, Craig D. Ellermeier

Research output: Contribution to journalArticlepeer-review

40 Scopus citations

Abstract

During growth in the environment, bacteria encounter stresses which can delay or inhibit their growth. To defend against these stresses, bacteria induce both resistance and repair mechanisms. Many bacteria regulate these resistance mechanisms using a group of alternative σ factors called extracytoplasmic function (ECF) σ factors. ECF σ factors represent the largest and most diverse family of σ factors. Here, we demonstrate that the activation of a member of the ECF30 subfamily of ECF σ factors, σV in Bacillus subtilis, is controlled by the proteolytic destruction of the anti-σ factor RsiV. We will demonstrate that the degradation of RsiV and, thus, the activation of σV requires multiple proteolytic steps. Upon exposure to the inducer lysozyme, the extracellular domain of RsiV is removed by an unknown protease, which cleaves at site 1. This cleavage is independent of PrsW, the B. subtilis site 1 protease, which cleaves the anti-σ factor RsiW. Following cleavage by the unknown protease, the N-terminal portion of RsiV requires further processing, which requires the site 2 intramembrane protease RasP. Our data indicate that the Nterminal portion of RsiV from amino acid 1 to 60, which lacks the extracellular domain, is constitutively degraded unless RasP is absent, indicating that RasP cleavage is constitutive. This suggests that the regulatory step in RsiV degradation and, thus, σV activation are controlled at the level of the site 1 cleavage. Finally, we provide evidence that increased resistance to lysozyme decreases σV activation. Collectively, these data provide evidence that the mechanism for σV activation in B. subtilis is controlled by regulated intramembrane proteolysis (RIP) and requires the site 2 protease RasP.

Original languageEnglish (US)
Pages (from-to)3135-3144
Number of pages10
JournalJournal of bacteriology
Volume195
Issue number14
DOIs
StatePublished - 2013
Externally publishedYes

Fingerprint

Dive into the research topics of 'The activity of σv;, an extracytoplasmic function σ factor of bacillus subtilis, is controlled by regulated proteolysis of the anti-σ factor rsiv'. Together they form a unique fingerprint.

Cite this