A disulfide bond-containing alkaline phosphatase triggers a BdbC-dependent secretion stress response in Bacillus subtilis

Appl Environ Microbiol. 2006 Nov;72(11):6876-85. doi: 10.1128/AEM.01176-06.

Abstract

The gram-positive bacterium Bacillus subtilis secretes high levels of proteins into its environment. Most of these secretory proteins are exported from the cytoplasm in an unfolded state and have to fold efficiently after membrane translocation. As previously shown for alpha-amylases of Bacillus species, inefficient posttranslocational protein folding is potentially detrimental and stressful. In B. subtilis, this so-called secretion stress is sensed and combated by the CssRS two-component system. Two known members of the CssRS regulon are the htrA and htrB genes, encoding potential extracytoplasmic chaperone proteases for protein quality control. In the present study, we investigated whether high-level production of a secretory protein with two disulfide bonds, PhoA of Escherichia coli, induces secretion stress in B. subtilis. Our results show that E. coli PhoA production triggers a relatively moderate CssRS-dependent secretion stress response in B. subtilis. The intensity of this response is significantly increased in the absence of BdbC, which is a major determinant for posttranslocational folding of disulfide bond-containing proteins in B. subtilis. Our findings show that BdbC is required to limit the PhoA-induced secretion stress. This conclusion focuses interest on the BdbC-dependent folding pathway for biotechnological production of proteins with disulfide bonds in B. subtilis and related bacilli.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaline Phosphatase / chemistry
  • Alkaline Phosphatase / genetics
  • Alkaline Phosphatase / metabolism*
  • Bacillus subtilis / enzymology
  • Bacillus subtilis / genetics
  • Bacillus subtilis / metabolism
  • Bacillus subtilis / physiology
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Biotechnology / methods
  • Escherichia coli Proteins
  • Gene Expression Regulation, Bacterial*
  • Heat-Shock Response*
  • Mutation
  • Protein Disulfide Reductase (Glutathione) / metabolism*
  • Protein Folding
  • Proteomics
  • Serine Endopeptidases / genetics
  • Serine Endopeptidases / metabolism

Substances

  • Bacterial Proteins
  • Escherichia coli Proteins
  • BdbC protein, Bacillus subtilis
  • Protein Disulfide Reductase (Glutathione)
  • Alkaline Phosphatase
  • phoA protein, E coli
  • Serine Endopeptidases
  • YkdA protein, Bacillus subtilis
  • YvtA protein, Bacillus subtilis