We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Characterization of the cspB gene encoding PS2, an ordered surface-layer protein in Corynebacterium glutamicum.
- Authors
Peyret, J. L.; Bayan, N.; Joliff, G.; Gulik-Krzywicki, T.; Mathieu, L.; Shechter, E.; Leblon, G.
- Abstract
PS2 is one of two major proteins detected in the culture media of various <em>Corynebacterium glutamicum</em> strains. The coding and promoter regions of the <em>cspB</em> gene encoding PS2 were cloned in tambda gt11 using polyclonal antibodies raised against PS2 for screening. Expression of the <em>cspB</em> gene in <em>Escherichia coli</em> led to the production of a major anti-PS2 labelled peptide of 63 000 Da, corresponding presumably to the mature form of PS2. it was detected in the cytoplasm, periplasm and surrounding medium of <em>E. coli</em>. Three other slower migrating bands of 65000, 68 000 and 72000Da were detected. The largest one probably corresponds to the precursor form of PS2 in <em>E. coli</em> Analysis of the nucleotide sequence revealed an open reading frame (ORF) of 1533 nucleotides. The deduced 510-amino-acid polypeptide had a calculated molecular mass of 55 426 Da. According to the predicted amino acid sequence, PS2 is synthesized with a <em>N</em>-terminal segment of 30-amino-acid residues reminiscent of eukaryotic and prokaryotic signal peptides, and a hydrophobic domain of 21 residues near the <em>C</em>-terminus. Although no significant homologies were found with other proteins, it appears that some characteristics and the amino acid composition of PS2 share several common features with surface-layer proteins. The <em>cspB</em> gene was then disrupted in <em>C. glutamicum</em> by gene replacement. Freeze-etching electron microscopy performed on the wild-type strain indicated that the cell wall of <em>C. glutamicum</em> is covered with an ordered surface of proteins (surface layer, S-layer) which is in very close contact with other cell-wall components. These structures are absent from the <em>cspB</em>-disrupted strain but are present after reintroduction of the <em>cspB</em> gene on a plasmid into this mutant. Thus we demonstrate that the S-layer protein is the product of the <em>cspB</em> gene.
- Subjects
PROTEINS; ESCHERICHIA coli; CORYNEBACTERIUM; CYTOPLASM; NUCLEOTIDE sequence; AMINO acid sequence
- Publication
Molecular Microbiology, 1993, Vol 9, Issue 1, p97
- ISSN
0950-382X
- Publication type
Article
- DOI
10.1111/j.1365-2958.1993.tb01672.x