甲真菌病分离菌株细胞外水解酶活性的测定

Analysis of extraceUular enzymatic activity of fungi isolated from patients with onychomycosit

目的对常见的甲真菌病分离菌株进行细胞外水解酶活性测定，以期发现可能与甲真菌病发病相关的毒力因子。方法诱导培养基为含甲碎片的培养基，受试菌株包括常见皮肤癣菌、非皮肤癣菌的标准菌株及临床分离自甲真菌病的红色毛癣菌。细胞外水解酶谱的测定体系采用法国生物-梅里埃公司的酶活性测试试剂盒APIZYM。结果与非皮肤癣菌相比，来自于含甲碎片培养基的皮肤癣菌的酯酶、酯脂肪酶、N-乙酰-β-氨基葡萄糖苷酶和a-甘露糖苷酶活性增加（P〈0．05）。与非红色毛癣菌相比，来自于含甲碎片培养基的红色毛癣菌N-乙酰-β-氨基葡萄糖苷酶活性升高（P〈0．05）。临床评分指数不同积分段甲真菌病的红色毛癣菌临床分离株除萘酚-AS—BI-磷酸水解酶外，其余酶的活性差异均无统计学意义（P〉0．05）。结论在特定环境中，水解酶的活性与菌株的种类有关，并对甲真菌病的临床表现可能有一定影响。

Objective To determine the extracellular enzymatic activity of common pathogens for ony- chomyeosis, in the hope of finding virulence factors associated with the pathogenesis of onychomycosis. Methods Strains tested in this study included standard strains of common dermatophyte and non-dermatophyte fungi as well as clinical isolates of Trichophyton rubrum from patients with onychomycosis. All the tested strains were cultured in medium containing nail fragments at 25 ~C for 10 to 21 days followed by the determination of extraceUular enzymatic activity with semi-quantitative API-ZYM test （bioM6rieux）. Results After culture in the nail fragment-containing medium, a significant increase was observed in the activities of esterase, esterase lipase, N-acetyl=13-glucosaminidase and c^-mannosidase in dermatophytes compared with non-dermatophytes （all P 〈 0.05）, as well as in the activity of N-acetylq3-glucosaminidase in Trichophyton rubrum compared with the other tested species of fungi （all P 〈 0.05）. No significant difference was noted in the activity of extracellu- lar enzymes, except for that of naphthol-AS-BI-phosphohydrolase, between the isolates of Triehophyton rubrum from patients with different ranges of scoring clinical index for onychomycosis （SCIO）. Conclusions In specific conditions, the extracellular enzymatic activity of fungi isolated from patients with onychomycosis is associated with fungal species, and may have a certain influence on the manifestations of anychomycosis.