A glycosyltransferase involved in biosynthesis of triglycosylated glycopeptidolipids in Mycobacterium smegmatis:: Impact on surface properties
A glycosyltransferase involved in biosynthesis of triglycosylated glycopeptidolipids in Mycobacterium smegmatis:: Impact on surface properties
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DOI：
10.1128/jb.187.21.7283-7291.2005
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发表时间：
2005-11-01
影响因子：
3.2
通讯作者：
Reyrat, JM
中科院分区：
文献类型：
--
作者：
Deshayes, C;Laval, F;Reyrat, JM
分枝杆菌的细胞膜是一种复杂的结构，在细胞与环境的相互作用和免疫系统的抗菌活性保护中发挥着重要作用。糖肽糖脂是存在于许多分枝杆菌表面的物种或类型特异性糖脂，其特征是糖基化模式具有很高的可变性。这些GPL具有各种生物活性，这些生物活性主要依赖于覆盖核心分子的糖。在污垢分枝杆菌中，GPL核心可以被两个或三个脱氧己糖取代。在这项研究中，我们证明Gtf3是一种糖基转移酶，负责合成三糖化的GPLs。结合质谱学和化学降解法对这些分子进行的生化分析表明，它们含有三个脱氧己糖部分。三聚糖化GPL的存在与细胞表面修饰有关，这种修饰导致滑动运动性降低，以及刚果红上细胞聚集和集落外观的改变。系统发育分析表明，GO是一个在分枝杆菌中保守的糖基转移酶家族成员。
The cell envelope of mycobacteria is a complex structure that plays an important role in the interactions of the cell with its environment and in the protection against the antimicrobial activity of the immune system. Glycopeptidolipids (GPLs) are species- or type species-specific glycolipids that are present at the surface of a number of mycobacteria and that are characterized by a high variability in glycosylation patterns. These GPLs possess various biological activities that depend mostly on the sugars capping the core molecule. In Mycobacterium smegmatis, the GPL core can be substituted by either two or three deoxyhexoses. In this study, we show that Gtf3 is a glycosyltransferase responsible for the synthesis of the triglycosylated GPLs. Biochemical analysis of these molecules, with a combination of mass spectrometry and chemical degradation methods, has shown that they contain three deoxyhexose moieties. The presence of the triglycosylated GPLs is associated with cell surface modifications that lead to a decrease in sliding motility as well as a modification in cellular aggregation and colony appearance on Congo red. Phylogenetic analysis indicated that GO is a member of a yet-uncharacterized glycosyltransferase family conserved among the mycobacteria.