Investigation on the linkage units between cell surface substances

本课题研究了细胞表面物质间连接单元的结构和作用。就我们所研究的而言，具有相当简单的骨架重复单元的磷壁酸链，如甘油磷壁酸、核糖醇磷壁酸、聚（GlcNAc-1-P）和聚（半乳糖基-甘油磷酸），似乎通过特殊的连接单元与肽聚糖连接，而不管它们在骨架链和糖苷分支中的结构多样性。每个连接单元由连接糖部分和含有一个或多个甘油磷酸残基的外部部分组成。显示了两种类型的连接糖部分的存在，即在多种细菌中的ManNAc-GlcNAc（或ManNAc-GlcN）类型和在有限数量的细菌中的Glc-GlcNAc类型。另一方面，外部部分的结构根据细菌种类而分化：Gro-P，在L. plantarum; <（Gro-P）_2>，在B. <（Gro-P）_3>，在S. aureus和B.凝结 ...更多信息 ans; <（Gro-P）_7>，在B中。短小杆菌属;李斯特菌属中的Glc-Glc-Gro-P。与上述磷壁酸相比，几乎所有的磷壁酸和少量的磷壁酸（在B.具有复杂骨架重复单元的蛋白质（例如，蛋白质）（例如，凝结蛋白）显示直接连接到肽聚糖，而没有任何特殊的连接单元。壁聚合物与肽聚糖的连接类型似乎与聚合物链的生物合成模式基本相关。铁胡酸链的从头生物合成是通过在S. aureus，B. B.枯草芽孢杆菌（B. subtilis）、B.凝结物和其他细菌。另一方面，磷糖醛酸和壁中性多糖的生物合成被证明是通过形成重复单元结合的脂质中间体进行的。该项目的结果似乎对理解细胞表面物质的组装有价值。少

In this project, the structure and role of linkage units between the cell surface substances were investigated. As far as we have studied, teichoic acid chains with rather simple backbone repeating units, such as glycerol teichoic acid, ribitol teichoic acid, poly(GlcNAc-1-P), and poly(galactosyl-glycerol phosphate), seem to be linked to peptidoglycan through special linkage units, irrespective of their structural diversity in the backbone chains and glycosidic branches. Each of the linkage units consists of a linkage sugar part and an outer part containing one or more glycerol phosphate residues. The presence of two types of the linkage sugar parts is shown, namely the ManNAc-GlcNAc (or ManNAc-GlcN) type in a wide variety of bacteria and the Glc-GlcNAc type in a limited number of bacteria. On the other hand, the structures of the outer parts are divesified depending on the bacterial species: Gro-P, in L. plantarum; <(Gro-P)_2> , in B. subtilis; <(Gro-P)_3> , in S. aureus and B. coagul … More ans; <(Gro-P)_7> , in B. pumilus; Glc-Glc-Gro-P, in Listeria. The glycerol phosphate part is expected to provide a valuable markers in phylogenetic classification of gram-positive bacteria.In contrast to above teichoic acids, almost all of teichuronic acids and a minor teichoic acid (in B. coagulans) with complex backbone repeating units are shown to be directly linked to peptidoglycan without any special linkage unit. The types of junction of wall polymers to peptidoglycan seem to be essentially related to the modes of biosynthesis of the polymer chains. The de novo biosynthesis of tiechoic acid chains is shown to proceed through the prior formation of linkage-unit-bound lipid intermediates in the membrane systems of S. aureus, B. subtilis, B. coagulans, and other bacteria. On the other hand, the biosynthesis of teichuronic acids and wall neutral polysaccharides is shown to proceed through the formation of repeating-unit-bound lipid intermediates. The results of this project seem to be valuable for understanding the assembly of cell surface substances. Less