TY - JOUR
T1 - Functional analysis of paralogous thiol-disulfide oxidoreductases in Bacillus subtilis
AU - Bolhuis, Albert
AU - Venema, Gerard
AU - Quax, Wim J.
AU - Bron, Sierd
AU - Van Dijl, Jan Maarten
PY - 1999/8/27
Y1 - 1999/8/27
N2 - The in vivo formation of disulfide bonds, which is critical for the stability and/or activity of many proteins, is catalyzed by thiol-disulfide oxidoreductases. In the present studies, we show that the Gram-positive eubacterium Bacillus subtilis contains three genes, denoted bdbA, bdbB, and bdbC, for thiol-disulfide oxidoreductases. Escherichia coli alkaline phosphatase, containing two disulfide bonds, was unstable when secreted by B. subtilis cells lacking BdbB or BdbC, and notably, the expression levels of bdbB and bdbC appeared to set a limit for the secretion of active alkaline phosphatase. Cells lacking BdbC also showed decreased stability of cell- associated forms of E. coli TEM-β-lactamase, containing one disulfide bond. In contrast, BdbA was not required for the stability of alkaline phosphatase or β-lactamase. Because BdbB and BdbC are typical membrane proteins, our findings suggest that they promote protein folding at the membrane-cell wall interface. Interestingly, pre-β-lactamase processing to its mature form was stimulated in cells lacking BdbC, suggesting that the unfolded form of this precursor is a preferred substrate for signal peptidase. Surprisingly, cells lacking BdbC did not develop competence for DNA uptake, indicating the involvement of disulfide bond-containing proteins in this process. Unlike E. coli and yeast, none of the thiol-disulfide oxidoreductases of B. subtilis was required for growth in the presence of reducing agents. In conclusion, our observations indicate that BdbB and BdbC have a general role in disulfide bond formation, whereas BdbA may be dedicated to a specific process.
AB - The in vivo formation of disulfide bonds, which is critical for the stability and/or activity of many proteins, is catalyzed by thiol-disulfide oxidoreductases. In the present studies, we show that the Gram-positive eubacterium Bacillus subtilis contains three genes, denoted bdbA, bdbB, and bdbC, for thiol-disulfide oxidoreductases. Escherichia coli alkaline phosphatase, containing two disulfide bonds, was unstable when secreted by B. subtilis cells lacking BdbB or BdbC, and notably, the expression levels of bdbB and bdbC appeared to set a limit for the secretion of active alkaline phosphatase. Cells lacking BdbC also showed decreased stability of cell- associated forms of E. coli TEM-β-lactamase, containing one disulfide bond. In contrast, BdbA was not required for the stability of alkaline phosphatase or β-lactamase. Because BdbB and BdbC are typical membrane proteins, our findings suggest that they promote protein folding at the membrane-cell wall interface. Interestingly, pre-β-lactamase processing to its mature form was stimulated in cells lacking BdbC, suggesting that the unfolded form of this precursor is a preferred substrate for signal peptidase. Surprisingly, cells lacking BdbC did not develop competence for DNA uptake, indicating the involvement of disulfide bond-containing proteins in this process. Unlike E. coli and yeast, none of the thiol-disulfide oxidoreductases of B. subtilis was required for growth in the presence of reducing agents. In conclusion, our observations indicate that BdbB and BdbC have a general role in disulfide bond formation, whereas BdbA may be dedicated to a specific process.
UR - http://www.scopus.com/inward/record.url?scp=0033609929&partnerID=8YFLogxK
U2 - 10.1074/jbc.274.35.24531
DO - 10.1074/jbc.274.35.24531
M3 - Article
C2 - 10455116
AN - SCOPUS:0033609929
SN - 0021-9258
VL - 274
SP - 24531
EP - 24538
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 35
ER -