The 1.9 Å crystal structure of Escherichia coli MurG, a membrane-associated glycosyltransferase involved in peptidoglycan biosynthesis
The 1.9 Å crystal structure of Escherichia coli MurG, a membrane-associated glycosyltransferase involved in peptidoglycan biosynthesis
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DOI：
10.1110/ps.9.6.1045
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发表时间：
2000-06-01
期刊：
影响因子：
8
通讯作者：
Walker, S
中科院分区：
文献类型：
--
作者：
Ha, S;Walker, D;Walker, S
报道了一种参与肽聚糖生物合成的膜相关糖基转移酶的1.9埃X射线结构。这种名为MURG的酶含有两个被深裂隙隔开的α/β开放片域。结构分析表明，C-末端含有UDP-GlcNAc结合部位，N-末端含有受体结合部位和可能的膜结合部位。结合来自其他Murg同系物的序列数据，这一结构提供了对底物结合和催化重要的残基的洞察。我们还注意到，在许多UDP-糖转移酶中发现的保守区域映射到Murg供体结合区的β/α/β/α超二级结构基序，这一观察结果可能有助于糖基转移酶结构的预测。在不同的UDP-糖转移酶中涉及供体结合的保守结构基序的鉴定也表明，有可能识别-甚至改变-帮助确定供体特异性的残基。
The 1.9 Angstrom X-ray structure of a membrane-associated glycosyltransferase involved in peptidoglycan biosynthesis is reported. This enzyme, MurG, contains two alpha/beta open sheet domains separated by a deep cleft. Structural analysis suggests that the C-terminal domain contains the UDP-GlcNAc binding site while the N-terminal domain contains the acceptor binding site and likely membrane association site. Combined with sequence data from other MurG homologs, this structure provides insight into the residues that are important in substrate binding and catalysis. We have also noted that a conserved region found in many UDP-sugar transferases maps to a beta/alpha/beta/alpha supersecondary structural motif in the donor binding region of MurG, an observation that may be helpful in glycosyltransferase structure prediction. The identification of a conserved structural motif involved in donor binding in different UDP-sugar transferases also suggests that it may be possible to identify-and perhaps alter-the residues that help determine donor specificity.