Shen Yang, Boulos Samy, Sumrall Eric, Gerber Benjamin, Julian-Rodero Alicia, Eugster Marcel R, Fieseler Lars, Nyström Laura, Ebert Marc-Olivier, Loessner Martin J
From the Laboratory of Food Microbiology, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich,
the Laboratory of Food Biochemistry, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zurich.
J Biol Chem. 2017 Oct 27;292(43):17832-17844. doi: 10.1074/jbc.M117.813964. Epub 2017 Sep 14.
Wall teichoic acids (WTAs) are the most abundant glycopolymers found on the cell wall of many Gram-positive bacteria, whose diverse surface structures play key roles in multiple biological processes. Despite recent technological advances in glycan analysis, structural elucidation of WTAs remains challenging due to their complex nature. Here, we employed a combination of ultra-performance liquid chromatography-coupled electrospray ionization tandem-MS/MS and NMR to determine the structural complexity of WTAs from species. We unveiled more than 10 different types of WTA polymers that vary in their linkage and repeating units. Disparity in GlcNAc to ribitol connectivity, as well as variable -acetylation and glycosylation of GlcNAc contribute to the structural diversity of WTAs. Notably, SPR analysis indicated that constitution of WTA determines the recognition by bacteriophage endolysins. Collectively, these findings provide detailed insight into cell wall-associated carbohydrates, and will guide further studies on the structure-function relationship of WTAs.
壁磷壁酸(WTAs)是许多革兰氏阳性细菌细胞壁上含量最丰富的糖聚合物,其多样的表面结构在多种生物学过程中发挥关键作用。尽管近年来聚糖分析技术取得了进展,但由于WTAs的性质复杂,其结构解析仍然具有挑战性。在这里,我们采用超高效液相色谱-电喷雾电离串联质谱/质谱和核磁共振相结合的方法来确定来自不同物种的WTAs的结构复杂性。我们揭示了10多种不同类型的WTA聚合物,它们在连接方式和重复单元上有所不同。GlcNAc与核糖醇连接的差异,以及GlcNAc可变的乙酰化和糖基化导致了WTAs的结构多样性。值得注意 的是,表面等离子体共振(SPR)分析表明,WTA的组成决定了噬菌体溶菌酶的识别。总的来说,这些发现为细胞壁相关碳水化合物提供了详细的见解,并将指导对WTAs结构-功能关系的进一步研究。