The bacterial cell wall is the target for many antibiotics, which disturb the balance between extracellular autolytic enzymes and the cell wall biosynthesis necessary for growth. Novak et al. screened a library of loss-of-function mutants for penicillin tolerance in order to pinpoint genes that are responsible for regulating bacterial autolysis. A two-component signaling system, VncR-VncS, was identified along with a 27-amino acid peptide (Pep27) and a membrane transporter, Vex. Secretion of endogenous Pep27 and detection by the VncR/S system was important for antibiotic-mediated cell death. Cells with disrupted pep27 and vex genes or disrupted vncS were tolerant to a broad range of antibiotics.—NG
Mol. Cell5, 49 (2000).