TY - JOUR
T1 - A macromolecular complex formed by a pilin-like protein in competent Bacillus subtilis
AU - Chen, Inês
AU - Provvedi, Roberta
AU - Dubnau, David
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2006/8/4
Y1 - 2006/8/4
N2 - In competent Bacillus subtilis, the ComG proteins are required to allow exogenous DNA to access to membrane-bound receptor ComEA during transformation. Here we describe a multimeric complex containing the pilin-like protein ComGC. Due to similarities to the type 4 pilus and the type 2 secretion system pseudopilus, we have tentatively named it the "competence pseudopilus." The ComGC multimer is released from cells upon digestion of the cell wall with lysozyme and has a heterogeneous size, estimated to range between 40 and 100 monomers, covalently linked by disulfide bonds. We determined that the prepilin peptidase ComC, the thiol-disulfide oxidoreductase pair BdbDC, and all seven ComG proteins are necessary to form the pseudopilus. Furthermore, these proteins are also sufficient to form a functional complex, i.e. able to facilitate binding of exogenous DNA to ComEA. The initial steps of pseudopilus biogenesis include the processing of ComGC in the cytoplasmic membrane and consist of two independent events, proteolytic cleavage by ComC and formation of an intramolecular disulfide bond by BdbDC. The other ComG proteins are required to assemble the mature ComGC monomers in the membrane into a multimeric complex proposed to span the cell envelope. We discuss the possible role of the competence pseudopilus in DNA binding and uptake during transformation.
AB - In competent Bacillus subtilis, the ComG proteins are required to allow exogenous DNA to access to membrane-bound receptor ComEA during transformation. Here we describe a multimeric complex containing the pilin-like protein ComGC. Due to similarities to the type 4 pilus and the type 2 secretion system pseudopilus, we have tentatively named it the "competence pseudopilus." The ComGC multimer is released from cells upon digestion of the cell wall with lysozyme and has a heterogeneous size, estimated to range between 40 and 100 monomers, covalently linked by disulfide bonds. We determined that the prepilin peptidase ComC, the thiol-disulfide oxidoreductase pair BdbDC, and all seven ComG proteins are necessary to form the pseudopilus. Furthermore, these proteins are also sufficient to form a functional complex, i.e. able to facilitate binding of exogenous DNA to ComEA. The initial steps of pseudopilus biogenesis include the processing of ComGC in the cytoplasmic membrane and consist of two independent events, proteolytic cleavage by ComC and formation of an intramolecular disulfide bond by BdbDC. The other ComG proteins are required to assemble the mature ComGC monomers in the membrane into a multimeric complex proposed to span the cell envelope. We discuss the possible role of the competence pseudopilus in DNA binding and uptake during transformation.
UR - http://www.scopus.com/inward/record.url?scp=33746818692&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33746818692&partnerID=8YFLogxK
U2 - 10.1074/jbc.M604071200
DO - 10.1074/jbc.M604071200
M3 - Article
C2 - 16751195
AN - SCOPUS:33746818692
VL - 281
SP - 21720
EP - 21727
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 31
ER -