Listeria monocytogenes EGD lacking penicillin-binding protein 5 (PBP5) produces a thicker cell wall.
We report on the cloning of the structural gene for penicillin-binding protein 5 (PBP5), lmo2754. We also describe the enzymatic activity of PBP5 and characterize a mutant lacking this activity. Purified PBP5 has dd-carboxypeptidase activity, removing the terminal D-alanine residue from murein pentapeptide side chains. It shows higher activity against low molecular weight monomeric pentapeptide substrates compared to dimeric pentapeptide compound. Similarly, PBP5 preferentially cleaves monomeric pentapeptides present in high-molecular weight murein sacculi. A Listeria monocytogenes mutant lacking functional PBP5 was constructed. Cells of the mutant are viable, showing that the protein is dispensable for growth, but grow slower and have thickened cell walls.
Korsak
Dorota
D
Department of General Microbiology, Institute of Microbiology, Warsaw University, Warsaw, Poland.
Vollmer
Waldemar
W
Markiewicz
Zdzislaw
Z
D001426:Bacterial Proteins / Q000378:metabolism; D002268:Carboxypeptidases / Q000378:metabolism; D002473:Cell Wall / Q000502:physiology*; D008089:Listeria monocytogenes / Q000201:enzymology / Q000378:metabolism* / Q000648:ultrastructure; D046915:Penicillin-Binding Proteins / Q000172:deficiency*; D010457:Peptidoglycan / Q000737:chemistry / Q000378:metabolism*
D001426:Bacterial Proteins; D046915:Penicillin-Binding Proteins; D010457:Peptidoglycan; D002268:Carboxypeptidases