变异链球菌UA159细胞壁蛋白的预测和功能分析

摘要

[目的] 对变异链球菌UA159细胞壁蛋白进行预测和功能分析,为后续研究该菌致病机制奠定基础.[方法] 用Phobius和SignalP 4.0软件预测变异链球菌UA159的细胞壁蛋白,并采用COG功能数据库对细胞壁蛋白进行功能注释.[结果] 变异链球菌UA159共含有 22个细胞壁蛋白,其中含有LPxTG锚定基序的有12个,含有LysM基序的有3个,含有CW基序的有5个,含有GW基序的有1个,含有PG锚定基序的有1个.功能分析结果显示,22个细胞壁蛋白中有18个蛋白没有具体的功能注释,4个蛋白有具体的功能注释,其中 beta-lactamase与防御机制功能有关;exo-beta-D-fructosidase与碳水化合物代谢与转运有关;分子伴侣蛋白ATP-dependent protease ClpE与蛋白质翻译后修饰和蛋白质折叠有关;cell wall-associated protein WapA与细胞壁和细胞膜的生物合成有关.[结论] 变异链球菌UA159全基因组大多数的细胞壁蛋白功能未知,需在以后研究中进行进一步的功能注释.%[Objective]The genome sequence of Streptococcus mutans UA159 was studied to predict the proteins anchored in the cell wall by bioinformatics method,which lay the foundation for further study of the pathogenic mechanism of the strain.[Method]The cell wall proteins of S.mutans UA159 were predicted by using Phobius and SignalP 4.0 softwares.The function analysis of cell wall proteins were predicted by using the functional database of Cluster of Orthologous Groups of proteins (COG).[Result]There had 22 cell wall proteins in the genome of S.mutans UA159,in which 12 proteins had LPxTG anchor motif,3 proteins had LysM motif,5 proteins had CW motif,1 protein had GW motif,and 1 protein had PG anchor motif.Functional analysis results showed that 18 proteins of the 22 cell wall proteins had no functional annotations,4 proteins had functional annotations,beta-lactamase protein was related to defensive mechanism function; exo-beta-D-fructosidase protein was related to carbohydrate metabolism and transport; ATP-dependent protease ClpE protein was molecular chaperone protein ,which related to protein post-translational modification and protein folding,cell wall-associatied protein WapA was related to cell wall/membrane biosynthesis.[Conclusion]Most of the cell wall proteins of S.mutans UA159 genome are unknown,and further functional annotations are needed in future study.