中文摘要：

研究了从家蚕消化道内分离出的4株肠球菌（C1、GC、FD、A20）的生理生化特征和16S rDNA序列，并与肠球菌种特异性探针序列进行了比较。生理生化特征测定结果表明，除A20外，C1、GC和FD与蒙氏肠球菌种的特征基本一致。由16S rDNA序列分析结果可知，分离菌株均与蒙氏肠球菌（Ent．mundtii AJ301836）有高度同源性，在系统发育树内位于同一分支。分析肠球菌种特异性探针序列，分离菌株的16S rDNA含有与蒙氏肠球菌种特异性探针完全相同的序列。因此认为家蚕消化道内存在蒙氏肠球菌。

英文摘要：

Four Enterococcus strains, namely C1, FD, GC and A20, were isolated from the intestine of the silkworm, Bombyx mori. The biochemical characteristics and 16S rDNA sequences of the isolates were studied and the sequence similarity between the 16S rDNAs and species-specific probes of Enterococci were compared. The results showed that the biochemical characteristics of all isolates were coincided with that of Enterococcus munddtii, except A20. Blast analysis and the phylogenetic tree showed their 16S rDNAs were highly homologous to that of Ent. mundtii （AJ301836）. Sequence analysis revealed that the 16S rDNA sequences of the isolates included the same sequence as the species-specific probe of Ent. mundtii implying that Ent. mundtii exists in the intestine of the silkworm.