肠道沙门氏菌O-抗原多糖的研究进展

Research advances in O-antigen polysaccharide of Salmonella enterica

摘要:

O-抗原是由多糖重复单元组成的多聚糖，表达于细菌的外膜，具有多样性，是划分沙门菌血清型的重要依据。O-抗原多糖由多基因协同作用而合成，这些基因在沙门菌基因组上成簇存在，形成O-抗原基因簇。O-抗原多糖也是重要的毒力因子，在沙门菌入侵宿主、体内存活、定殖等致病过程中均发挥着重要的作用。此外，O-抗原还是沙门菌主要的保护性抗原，能激发宿主产生高水平抗体并发挥免疫保护作用，成为疫苗研究的靶点。本文综述O-抗原多糖的基因结构和合成、生物学功能及其在疫苗研制中的应用与前景。

关键词:沙门氏菌，O-抗原多糖，基因结构，毒力，疫苗

Abstract:

O-antigen (O-polysaccharide) is a part of the lipopolysaccharide component of the outer membrane of Salmonella and consists of oligosaccharide repeats (O units). It is one of the most variable cell constituents and the diversity is a common basis for bacterial serotyping. Genes, which are responsible for O-polysaccharide synthesis and translocation, exist in Salmonella genome into cluster, called O-antigen gene cluster. The presence of O antigen plays a role in bacterial virulence and is essential for invasion, survival and colonization of bacteria in their natural environment. Besides, O-antigen is also a major protective antigen of Salmonella, and it can stimulate the host to produce strong immune responses, which contribute to bacteria elimination. Thus, it has extensively been targeted for vaccine development. This review summarizes O-antigen in terms of gene structures, synthesis, function and its application in vaccine development.

Key words:Salmonella, O-antigen polysaccharide, Gene structure, Virulence, Vaccine