表皮葡萄球菌icaA和icaD基因表达及其与黏质物形成的关系

目的了解临床分离的表皮葡萄球菌所携带的icaA和icaD操纵子表达情况及其与黏质物形成之间的关系。方法收集1CU临床分离的表皮葡萄球菌62株，采用刚果红法检测其黏质物形成，PCR法检测icaA、icaD基因表达，卡方检验法进行统计学处理。结果62株表皮葡萄球菌中产黏质物菌株有26株（41．9％）；产黏质物菌株中icaA、icaD基因表达阳性的菌株分别为22株（84．6％）和19株（73．1％），icaA、icaD基因表达均为阳性有17株（65．4％），明显高于非产黏质物菌株（P〈0．01）；icaA、icaD基因表达均阴性为2株（7．7％），明显低于非产黏质物菌株（P〈0．01）。结论icaA、icaD基因表达对表皮葡萄球菌的黏质物产生具有重要影响，但并不是其唯一的影响因素。

Relationship between icaA, icaD gene expression and slime formation in Staphylococcus epidermidis

Objective To study the relationship between icaA, icaD gene expression and slime formation in Staphylococcus epidermidis strains isolated from ICU. Methods Slime-forming ability of 62 strains of S. epidermidis was tested on Congo red agar plates. The icaA, icaD gene expression was analyzed by PCR. The data were analyzed by Chi-square test. Results Slime production was identified in 41. 9% （26/62） of the strains. Gene icaA and icaD were expressed in 22 （84. 6%） and 19 （73.1%） of those slime-positive strains respectively. Both icaA and icaD genes were expressed in 17 （65.4%） strains. The prevalence of icaA, icaD gene expression in slime-producing S. epidermidis was higher than that in non-slime-producing S. epiderrnidis （P〈0. 01）. Two （7.7%） strains were negative for both icaA and icaD genes. Conclusions Expression of icaA and icaD genes plays an important role in slime formation in S. epidermidis.