Structural dissection and high-throughput screening of mannosylglycerate synthase
Structural dissection and high-throughput screening of mannosylglycerate synthase
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DOI：
10.1038/nsmb950
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发表时间：
2005-07-01
影响因子：
16.8
通讯作者：
Davies, GJ
中科院分区：
文献类型：
--
作者：
Flint, J;Taylor, E;Davies, GJ
活化甘露糖的酶促转移产生糖缀合物和寡糖和多糖中的甘露糖苷。然而，尽管其生物学的必要性，糖基转移酶识别甘露糖和催化其转移到受体分子的机制知之甚少。在这里，我们报告了广泛的高通量筛选和动力学分析的天然和合成底物的Rhodothermus marinus甘露糖甘油酸合酶（MGS），催化形成的应力保护剂2-O-α-D-甘露糖甘油酸。MGS的序列表明，它是在倒位和保留转移酶的尖端。载脂蛋白MGS的结构和与供体和受体分子（包括GDP-甘露糖）的复合物，结合结合和催化位点的诱变，揭示了甘露糖转移中心。核苷酸特异性在GDP-D-甘露糖识别中与供体糖的性质一样重要。
The enzymatic transfer of activated mannose yields mannosides in glycoconjugates and oligo- and polysaccharides. Yet, despite its biological necessity, the mechanism by which glycosyltransferases recognize mannose and catalyze its transfer to acceptor molecules is poorly understood. Here, we report broad high-throughput screening and kinetic analyses of both natural and synthetic substrates of Rhodothermus marinus mannosylglycerate synthase (MGS), which catalyzes the formation of the stress protectant 2-O-alpha-D-mannosyl glycerate. The sequence of MGS indicates that it is at the cusp of inverting and retaining transferases. The structures of apo MGS and complexes with donor and acceptor molecules, including GDP-mannose, combined with mutagenesis of the binding and catalytic sites, unveil the mannosyl transfer center. Nucleotide specificity is as important in GDP-D-mannose recognition as the nature of the donor sugar.