Transpeptidase-Mediated Incorporation of d-Amino Acids into Bacterial Peptidoglycan

详细信息    查看全文

• 作者：Tania J. Lupoli ; Hirokazu Tsukamoto ; Emma H. Doud ; Tsung-Shing Andrew Wang ; Suzanne Walker ; Daniel Kahne
• 刊名：Journal of the American Chemical Society
• 出版年：2011
• 出版时间：July 20, 2011
• 年：2011
• 卷：133
• 期：28
• 页码：10748-10751
• 全文大小：816K
• 年卷期：v.133,no.28(July 20, 2011)
• ISSN：1520-5126

文摘

The 尾-lactams are the most important class of antibiotics in clinical use. Their lethal targets are the transpeptidase domains of penicillin binding proteins (PBPs), which catalyze the cross-linking of bacterial peptidoglycan (PG) during cell wall synthesis. The transpeptidation reaction occurs in two steps, the first being formation of a covalent enzyme intermediate and the second involving attack of an amine on this intermediate. Here we use defined PG substrates to dissect the individual steps catalyzed by a purified E. coli transpeptidase. We demonstrate that this transpeptidase accepts a set of structurally diverse d-amino acid substrates and incorporates them into PG fragments. These results provide new information on donor and acceptor requirements as well as a mechanistic basis for previous observations that noncanonical d-amino acids can be introduced into the bacterial cell wall.