摘要
目的对两株来源于健康人肠道的耐酸耐胆盐菌株R92-2和R111进行鉴定和系统发育分析,以筛选优良的宿主菌株为最终构建能高效表达和分泌β-半乳糖苷酶的工程菌奠定基础。方法表型特征分析后,利用16SrDNA两端的保守序列作为PCR引物,扩增两株菌的16S rDNA序列并测序,测序结果于GenBank中Blastn并构建系统发育树。结果表型特征分析初步鉴定两株菌为乳酸菌。R92-2的16S rDNA序列与Weissella cibaria的16SrDNA序列同源性为100%;R111的16S rDNA序列与Enterococcus faecium的16S rDNA序列同源性为100%。结论R92-2为Weissella cibaria;R111为Enterococcus faecium。两株菌有望用于构建能高效表达和分泌β-半乳糖苷酶的工程菌。
Objective To screen bacteria for the engineering bacteria expressing and secreting high activity β-galactosidase, and two bacterial strains called as R92-2 and R111 with acid and bile resistances would be isolated from health human intestine to strain identification and phylogenetic analysis. Methods These two strains were first been identified with phenotype characteristic analysis. Then the 16S rDNAs of these two bacterial strains were amplified and sequenced with the primers designed by the conserve sequences. DNA sequences were blasted against GenBank, and the phylogenetic trees were constructed. Results Phenotype characteristic analysis showed that both of the bacterial strains belonged to lactic acid bacteria. Results of Blastn showed that 16S rDNAs of R92- 2 and Weissella cibaria had 100% homology; 16S rDNAs of R111 and Enterococcus faecium had 100% homology too. Conclusion R92-2 belongs to Weissella cibaria strain; R111 belongs to Enterococcus faecium strain. These two stains may be used to construct the engineering bacteria expressing and secreting high activity β-galactosidase.
出处
《四川大学学报（医学版）》
CAS
CSCD
北大核心
2008年第2期263-266,共4页
Journal of Sichuan University(Medical Sciences)
