Specific and general stress proteins in Bacillus subtilis � a two-dimensional protein electrophoresis study

Abstract

A computer-aided analysis of high resolution two-dimensional polyacrylamide gels was used to investigate the changes in the protein synthesis profile in B. subtilis wild-type strains and sigB mutants in response to heat shock, salt and ethanol stress, and glucose or phosphate starvation. The data provided evidence that the induction of a t least 42 general stress proteins absolutely required the alternative sigma factor oB. However, a t least seven stress proteins, among them ClpC, ClpP, Sod, AhpC and AhpF, remained stressinducible in a sigB mutant. Such a detailed analysis also permitted the description of subgroups of general stress proteins which are subject to additional regulatory circuits, indicating a very thorough fine-tuning of this complex response. The relative synthesis rate of the general stress proteins constituted up to 40% of the total protein synthesis of stressed cells and thereby emphasizes the importance of the stress regulon. Besides the induction of these general or rather unspecific stress proteins, the induction of stress-specif ic proteins is shown and discussed.

Limited Stress Response in Streptococcus pneumoniae

“…This increase in synthesis upon heat shock is similar to the increase in mRNA level of clpL and groEL, respectively, in the stationary growth phase of pneumococcus (30). In E. colt and B. subtilts, the synthesis of GroEL and DnaK was increased approximately 5-to 10-fold upon heat shock (4,22). This suggests that HSP synthesis in pneumococcus is quite similar to that of E. coli and B. subtilis.…”

A family of cold shock proteins in Bacillus subtilis is essential for cellular growth and for efficient protein synthesis at optimal and low temperatures

“…Therefore, sequence selectivity in RNA binding is apparent for CSPs but may not be high. Schmid et al (1997) and Bernhardt et al (1997). Other spots identified in Graumann et al (1996).…”

Proteome-wide analysis of the functional roles of bacilysin biosynthesis in Bacillus subtilis

“…However, activation of σ B activity following metabolic or environmental stress dramatically increases the transcription of the general stress genes (from approximately 1% in growing cells to 20% or even more in starved or stressed bacteria (Bernhardt et al, 1997).…”

“…Stress induction of this protein group was shown to be mediated by the alternative sigma factor σ B , the general stress sigma factor of grampositive bacteria. So far, more than 150 σ B -dependent genes have been identified by proteome studies and transcription profiling (Antelmann et al, 1997;Helmann et al, 2001;Petersohn et al, 2001;Price et al, 2001;Yu et al 2008). Many of the general stress genes display basal level transcription from vegetative σ A -dependent promoters.…”

“…However, each of the nadE (outB) mutants with reduced NAD synthetase activities was also impaired in growth at a permissive temperature of 35 °C, indicating the essential nature of this protein (Albertini et al, 1987). NadE was subsequently shown to belong to the family of σ B -dependent general stress proteins (Antelmann et al, 1997;Malcolm et al, 2001). In addition, transcriptional studies showed that nadE is strongly induced in response to heat, ethanol and salt stress or after starvation for glucose in a σ B -dependent manner.…”