Premium
Activation of the extracytoplasmic function σ factor σ V by lysozyme
Author(s) -
Ho Theresa D.,
Ellermeier Craig D.
Publication year - 2019
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/mmi.14348
Subject(s) - lysozyme , biology , signal peptidase , bacillus subtilis , protease , transmembrane protein , microbiology and biotechnology , cleavage (geology) , transcription factor , biochemistry , signal peptide , receptor , gene , enzyme , genetics , peptide sequence , bacteria , paleontology , fracture (geology)
Summary σ V 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 . σ V is activated by lysozyme and is required for lysozyme resistance. The activity of σ V 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 cascade which results in degradation of RsiV and activation of σ V . Like the anti‐σ factors for several other ECF σ factors, RsiV is degraded by a multistep proteolytic cascade that is regulated at the step of site‐1 cleavage. Unlike other anti‐σ 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 σ V leads to the transcription of genes, which encode proteins required for lysozyme resistance.