Unidad de Biofisica, Centro Mixto Consejo Superior de Investigaciones Cientificas-Universidad del País Vasco/Euskal Herriko Unibertsitatea, Leioa, Bizkaia 48940, Spain.
J Biol Chem. 2010 Oct 29;285(44):33577-83. doi: 10.1074/jbc.R110.168328. Epub 2010 Aug 27.
Phosphatidyl-myo-inositol mannosides (PIMs) are unique glycolipids found in abundant quantities in the inner and outer membranes of the cell envelope of all Mycobacterium species. They are based on a phosphatidyl-myo-inositol lipid anchor carrying one to six mannose residues and up to four acyl chains. PIMs are considered not only essential structural components of the cell envelope but also the structural basis of the lipoglycans (lipomannan and lipoarabinomannan), all important molecules implicated in host-pathogen interactions in the course of tuberculosis and leprosy. Although the chemical structure of PIMs is now well established, knowledge of the enzymes and sequential events leading to their biosynthesis and regulation is still incomplete. Recent advances in the identification of key proteins involved in PIM biogenesis and the determination of the three-dimensional structures of the essential phosphatidyl-myo-inositol mannosyltransferase PimA and the lipoprotein LpqW have led to important insights into the molecular basis of this pathway.
磷酸肌醇甘露糖脂（PIMs）是一种独特的糖脂，在所有分枝杆菌物种的细胞包膜的内外膜中大量存在。它们基于带有一个到六个甘露糖残基和多达四个酰基链的磷酸肌醇脂质锚。PIMs 不仅被认为是细胞包膜的重要结构组成部分，也是糖脂（甘露聚糖和阿拉伯半乳聚糖）的结构基础，所有这些在结核分枝杆菌和麻风分枝杆菌的宿主-病原体相互作用过程中都是重要的分子。尽管 PIMs 的化学结构现在已经确定，但对导致其生物合成和调节的酶和顺序事件的了解仍然不完整。最近在鉴定参与 PIM 生物发生的关键蛋白方面的进展以及确定必需的磷酸肌醇甘露糖基转移酶 PimA 和脂蛋白 LpqW 的三维结构，使人们对该途径的分子基础有了重要的了解。
