Wzz酶对O抗原糖链聚合度的调控

Regulation of the O-antigen polysaccharide chain length by Wzz－A review

摘要:

摘要:革兰氏阴性细菌表面的O 抗原在信号识别、黏附、免疫逃避等过程中发挥着重要作用。根据翻转酶的不同，O 抗原的合成可划分为3 种机制，其中依赖于Wzy的合成途径(Wzy-dependent)较为普遍。该机制中，wzz基因参与调节O抗原多糖的聚合度。O抗原糖链能够影响致病菌的抗原性并不同程度的刺激免疫系统。基于Wzz的蛋白晶体结构，对wzz基因进行分子改造可以使菌株合成不同大小的O抗原糖链。利用病原菌的O抗原与特定载体蛋白结合而成的糖缀合物疫苗，既具有很好的靶向性，又有较强的免疫原性。因此了解Wzz(调节糖链长短的蛋白)的功能、结构及作用机制对今后糖缀合物疫苗的开发与生产具有重要意义。

Abstract:

Abstract:The O-antigen of Gram-negative bacterium plays an important role in the signal identification，adhesion，immune evasion and other processes．There are three O-antigen polysaccharides biosynthesis mechanisms according to the type of the flippase that is involved． The Wzy-dependent mechanism is more commonly seen．In Wzy-dependent mechanism，the wzz gene is involved in regulating the length of O-antigen polysaccharide chain which can affect antigenicity of the pathogen and immune response of the host． Based on the crystal structure of Wzz ( regulator of the Oantigen polysaccharides length)，different length of O-antigen chain can be obtained through molecular modification of the gene wzz．Conjugating O-antigen or its mutants of a pathogen to a carrier protein could help to develop a vaccine that have both a good target specificity and a strong immunogenicity．Therefore，it is important to understand the function，structure and mechanism of Wzz for the development and production of glycoconjugates vaccine．