Thomas Scott, Yen Ten-Yang, Macher Bruce A
Glycobiology. 2002 Feb;12(2):4G-7G.
Significant progress has been made in discovering and cloning a host of eukaryotic glycosyltransferases, demonstrating the intricacy and complexity of protein and lipid glycosylation. The availability of their predicted amino acid sequences extended our insights into the structure/function aspects of this family of proteins. However, our knowledge of their three-dimensional structures and how structure gives rise to substrate binding and specificity is still limited. Glycosyltransferase X-ray crystal structures have begun to provide significant information on a limited number of enzymes. To date, only three eukaryotic glycosyltransferase crystal structures have been solved, and all of them are for enzymes that utilize a UDP-sugar. One of the important structural elements of a protein is its disulfide bonds. These covalent interactions place conformational constraints on the overall protein structure,providing some important structural information. In this letter, we outline our current understanding of the free Cys residues and disulfide bonds in eukaryotic glycosyltransferases and discuss some of the important outcomes of these findings.
在发现和克隆许多真核生物糖基转移酶方面已经取得了重大进展，这表明了蛋白质和脂质糖基化的错综复杂和复杂性。它们预测的氨基酸序列的可得性扩展了我们对该蛋白家族结构/功能方面的认识。然而，我们对它们的三维结构以及结构如何导致底物结合和特异性的了解仍然有限。糖基转移酶的X射线晶体结构已开始为有限数量的酶提供重要信息。迄今为止，仅解析出了三种真核生物糖基转移酶的晶体结构，并且所有这些结构都是针对利用UDP-糖的酶。蛋白质的一个重要结构元件是其二硫键。这些共价相互作用对整个蛋白质结构施加构象限制，提供一些重要的结构信息。在这封信中，我们概述了我们目前对真核生物糖基转移酶中游离半胱氨酸残基和二硫键的理解，并讨论了这些发现的一些重要成果。
