Cold shock proteins CspB and CspC are major stationary-phase-induced proteins in Bacillus subtilis

Shortly after the transition from exponential growth to stationary phase, t he pattern of protein synthesis in Bacillus subtilis changes markedly. Amon g the most profoundly induced proteins are two homologous small acidic prot eins, CspB and CspC, which are also major cold-shock-induced proteins. The third cold shock protein (CSP) in B. subtilis, CspD, is not induced followi ng entry into stationary phase. Deletion of both cspB and cspC genes has be en previously shown to lead to lysis of cells during stationary phase. Thes e findings reveal that CSPs in B. subtilis are induced under several stress conditions, and that an increase in the synthesis of CspB and CspC is need ed for efficient adaptation to stationary phase. Enhanced synthesis of CspB occurs through a combination of transcriptional and post-transcriptional a ctivation, indicating a mechanism similar to that mediating cold shock indu ction of CSPs. induction of CSPs in bacteria may be triggered by a common s ignal, the inactivation of ribosomes, occurring under both cold shock and s tationary-phase conditions.