刚果红平板法筛选血链球菌胞外多糖缺失突变株

摘要

Exopolysaccharide ( EPS) of bacteria not only can protect the cell from the changes of adverse circum-stances and invaders, but also has special biological activities in medical microbiology, including anti-radiation, anti-oxidation, and other properties.Although the EPS has caught the researchers’ extensive attention, yet the synthesis mechanism of EPS is still unclear.In this study, Streptococcus sanguis was used as a model organism, and a gene li-brary of the EPS formation mechanism by S.sanguis built by random insertion mutagenesis technique as tested sub-ject, an easy and practicable Congo red agar plate method was developed for screening the EPS deficient mutants, in order to provide a foundation for studying the formation mechanism of the EPS and screening the S.sanguis exopo-lysaccharide mutants in clinic in the days to come.%细菌胞外多糖不但能够保护细菌，防止外界环境变化和侵蚀者对菌体细胞的侵害，而且在医学微生物学中还具有特有的生物学活性，包括抗辐射、抗氧化等特性。尽管细菌胞外多糖受到了学者的广泛关注，但胞外多糖的生物合成机制还不十分清楚。以血链球菌为模式生物，以随机插入突变机制构建的血链球菌胞外多糖形成基因文库为受试对象，建立了一种简单易行的刚果红平板法用于筛选血链球菌细胞外粘多糖形成缺失突变株的方法，为日后研究细菌胞外多糖形成机制以及临床上筛选胞外多糖缺失突变株奠定了基础。