Determination of the cleavage site involved in C-terminal processing of penicillin-binding protein 3 of Escherichia coli.
Chromatographic peptide mapping of lysyl endopeptidase digests of penicillin-binding protein 3 (PBP 3) of Escherichia coli revealed peptides that differed in retention time between the precursor and mature forms. The peptides were purified from a processing-defective (prc) mutant and a wild-type (prc+) strain. These peptides were identified as the C-terminal region of the precursor form and mature PBP 3 by amino acid sequencing. Each of the C-terminal peptides was cleaved into two fragments by trypsin digestion. By sequencing the resultant carboxyl-side fragment derived from the mature form, it was concluded that the C-terminal residue of mature PBP 3 was Val-577, and thus the Val-577-Ile-578 bond is the cleavage site for processing. This conclusion was consistent with the amino acid compositions of the relevant peptides, which suggested that the peptide from the cleavage site to the end of the deduced sequence (Ile-578-Ser-588) was present in the precursor but absent in the mature form. One lysyl peptide bond resisted both lysyl endopeptidase and trypsin and remained uncleaved in the peptide analyzed above.
Nagasawa
H
H
Department of Agricultural Chemistry, University of Tokyo, Japan.
Sakagami
Y
Y
Suzuki
A
A
Suzuki
H
H
Hara
H
H
Hirota
Y
Y
D000217:Acyltransferases / Q000235:genetics*; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D001426:Bacterial Proteins; D002352:Carrier Proteins; D002851:Chromatography, High Pressure Liquid; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D029968:Escherichia coli Proteins; D006602:Hexosyltransferases / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000096:biosynthesis / Q000235:genetics*; D002267:Muramoylpentapeptide Carboxypeptidase; D046915:Penicillin-Binding Proteins; D010446:Peptide Fragments / Q000302:isolation & purification; D010447:Peptide Hydrolases; D010449:Peptide Mapping; D046928:Peptidoglycan Glycosyltransferase; D010458:Peptidyl Transferases / Q000096:biosynthesis / Q000235:genetics*; D011499:Protein Processing, Post-Translational
D000596:Amino Acids; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C478704:FtsI protein, E coli; D009097:Multienzyme Complexes; D046915:Penicillin-Binding Proteins; D010446:Peptide Fragments; D000217:Acyltransferases; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D046928:Peptidoglycan Glycosyltransferase; D010447:Peptide Hydrolases; D002267:Muramoylpentapeptide Carboxypeptidase