In vitro synthesis of cross-linked murein and its attachment to sacculi by PBP1A from Escherichia coli
In vitro synthesis of cross-linked murein and its attachment to sacculi by PBP1A from Escherichia coli
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DOI：
10.1074/jbc.m604083200
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发表时间：
2006-09-15
影响因子：
4.8
通讯作者：
Vollmer, Waldemar
中科院分区：
文献类型：
--
作者：
Born, Petra;Breukink, Eefjan;Vollmer, Waldemar
青霉素结合蛋白（PBP）1A是大肠杆菌中主要的胞壁素（肽聚糖）合酶。以放射性脂质Ⅱ为底物，体外研究PBP1A的胞壁素合成活性。PBP1A通过转糖基化产生胞壁蛋白聚糖链，并通过转肽作用形成肽交联。时程实验表明，PBP1A，不像PBP1B，需要存在的聚合聚糖链携带单体肽的交联活性。PBP1A能够将由放射性脂质II合成的新生胞壁素附着到未标记的胞壁素球囊上。新材料的附着通过转肽反应发生，其中球囊中的单体三肽和四肽是受体。
The penicillin-binding protein (PBP) 1A is a major murein (peptidoglycan) synthase in Escherichia coli. The murein synthesis activity of PBP1A was studied in vitro with radioactive lipid II substrate. PBP1A produced murein glycan strands by transglycosylation and formed peptide cross-links by transpeptidation. Time course experiments revealed that PBP1A, unlike PBP1B, required the presence of polymerized glycan strands carrying monomeric peptides for cross-linking activity. PBP1A was capable of attaching nascent murein synthesized from radioactive lipid II to nonlabeled murein sacculi. The attachment of the new material occurred by transpeptidation reactions in which monomeric tri- and tetrapeptides in the sacculi were the acceptors.