Investigation on the linkage units between cell surface substances

在本项目中，研究了细胞表面物质之间的连接单元的结构和作用。根据我们的研究，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-甘油磷酸)似乎通过特殊的连接单元与肽聚糖相连，而与它们在主链和糖苷支链中的结构多样性无关。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。结果表明，存在两种类型的连接糖部分，即在广泛的细菌中存在ManNAc-GlcNAc(或ManNAc-GlcN)型，在有限数量的细菌中存在GLC-GlcNAc型。另一方面，根据细菌种类的不同，细菌的外部结构也不同：在植物乳杆菌中为Gro-P；在枯草杆菌中为(Gro-P)_2&gt；在金黄色葡萄球菌中为(Gro-P)_3&gt；在金黄色葡萄球菌中为(Gro-P)_3&gt；在金黄色葡萄球菌中为…。更多的Ans；&lt；(Gro-P)_7&gt；，在B.puilus；GLC-Glc-Gro-P，在李斯特菌。磷酸甘油部分有望为革兰氏阳性细菌的系统发育分类提供有价值的标记。与上述磷壁酸不同，几乎所有的磷壁酸和少量具有复杂骨架重复单元的磷壁酸(在凝结杆菌中)都直接与肽聚糖相连，而不是任何特殊的连接单元。壁式聚合物与肽聚糖的连接类型似乎本质上与聚合物链的生物合成方式有关。硫代酸链的从头合成是通过在金黄色葡萄球菌、枯草杆菌、凝结杆菌和其他细菌的膜系统中预先形成连接单位结合的脂质中间体来进行的。另一方面，棕榈酸和壁中性多糖的生物合成是通过形成重复单位结合的脂类中间体进行的。这个项目的结果似乎对理解细胞表面物质的组装很有价值。较少

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