The catalytic mechanism of DD-peptidases: unexpected importance of tyrosine 280 in the transpeptidation reaction catalysed by the Streptomyces R61 DD-peptidase.
The study of the interactions between the Tyr280Phe mutant of the Streptomyces R61 DD-peptidase, various substrates and beta-lactam antibiotics shows that Tyr280 is involved not only in the formation of the acylenzyme with the peptide substrate and beta-lactam antibiotics, but also and specifically in the catalysis of the transpeptidation reaction. Surprisingly, this residue does not belong to the conserved structural and functional elements which characterise the penicillin-recognising enzymes.
Centre d'Ingénierie des Protéines, Université de Liège, Belgium.
J M
JM
Wilkin
J
J
Lamotte-Brasseur
J M
JM
Frère
D000596:Amino Acids / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000378:metabolism; D002268:Carboxypeptidases / Q000737:chemistry* / Q000378:metabolism; D002384:Catalysis; D004795:Enzyme Stability; D007700:Kinetics; D007769:Lactams; D009154:Mutation / Q000235:genetics; D010458:Peptidyl Transferases / Q000378:metabolism*; D011489:Protein Denaturation; D011994:Recombinant Proteins / Q000235:genetics; D046929:Serine-Type D-Ala-D-Ala Carboxypeptidase; D013302:Streptomyces / Q000201:enzymology*
D000596:Amino Acids; D000900:Anti-Bacterial Agents; D007769:Lactams; D011994:Recombinant Proteins; D010458:Peptidyl Transferases; D002268:Carboxypeptidases; D046929:Serine-Type D-Ala-D-Ala Carboxypeptidase