肠球菌毒力岛基因的检测

Detection of pathogenicity island-associated genes in enterococcal isolates

目的探索肠球菌中毒力岛基因的存在情况。方法使用PCR和杂交方法对155株肠球菌进行毒力岛相关基因检测。结果155株肠球菌中,88.39%携带至少一个毒力岛基因,各基因阳性率由高至低依次为hyd(81.94%),psaA(78.06%)、nuc(57.42%)、esp(53.55%)、cylB(52.90%)和gls24-like(38.06%);除esp基因,其他5个基因的阳性率均是粪肠球菌高于屎肠球菌,其中nuc、cylB、gls24-like三个基因的阳性率有统计学差异。粪肠球菌中临床分离株各基因的阳性率和所携带的基因数均高于健康人分离株。结论肠球菌普遍携带毒力岛相关基因,粪肠球菌各基因阳性率高于屎肠球菌,粪肠球菌中临床分离株所携带的毒力基因、毒力岛基因数目均明显高于健康人分离株。

Objective To investigate the presence of pathogenicity island （PAI）-associated genes in the enterococcal isolates. Methods Using PCR and hybridization methods, PAI-associated genes were detected in 155 enteococcal strains isolated from clinical patients and healthy individuals. Results Among the 155 enterococcal isolates, 137 （88.39%） carried at least one of PAI-associated genes, namely hyd （positivity rate of 81.94%）, psoA （78.06%）, hue （57.42%）, esp （53.55%）, cylB （52.90%）, and gls24-like （38.06%） genes. Expect for esp gene, the other 5 genes showed higher positivity rates in the E. faecalis strains than in the E. faeciurn strains, and this difference was statistically significant for the genes hue, cylB, and gls24-like. The positivity rates and the number of these genes in the E. faecolis from clinical isolates were both significantly higher than those in the strains isolated from healthy individuals. Conclusion The data show a wide distribution of the PAl-associated genes among the enterococcal strains, and E. faecalis strains are more likely than E. faeciurn strains to be positive for the 6 genes, which are present at significant higher rates in the clinically isolated samples than in that from healthy individuals .