中文摘要：

目的：测定不同孵育条件、来源和血清型的新生隐球菌分泌的胞外蛋白水解酶及丝氨酸蛋白酶的活性。方法：30℃和37℃下用含有偶氮白蛋白的琼脂培养板培养不同来源及血清型的36株新生隐球菌菌株，测量其产生的廓清晕环的大小，计算CH值[菌落半径／（菌落半径＋廓清晕环半径）]来比较其胞外蛋白水解酶及丝氨酸蛋白酶的活性强弱；用丝氨酸蛋白酶的特异性抑制剂观察两种酶活性改变；酶谱法观察菌株浓缩上清液中胞外蛋白水解酶活性和相对分子质量。结呆：36株菌株在30℃和37℃培养条件下它们的平均CH值分别为0．558±0．170和0．575±0．169，两者间无显著差异；血清A（n=13）、B（n=13）、D／AD（n=6）型菌株各自的平均CH值分别为0．564±0．144、0．515±0．078和0．482±0．072，各组间无显著差异；临床分离株（n=23）、环境分离株（n=9）和荚膜缺陷株（n=4）各自的平均CH值分别为0．570±0．177、0．513±0．069和0．942±0．075（P〈0．05）。对照组（不合抑肽酶）和抑肽酶不同浓度组（1．2、1．6mU）的平均CH值分别为0．459±0．188，0．975±0．287、0．733±0．252（P〈0．01）。菌株浓缩液中含有复杂的胞外蛋白酶类成分。结论：新生隐球菌胞外蛋白水解酶及丝氨酸蛋白酶的活性在30℃、37℃下无显著差异；在临床分离株中比环境分离株和荚膜缺陷株强；在不同血清型菌株间无显著差别；可被丝氨酸蛋白酶抑制剂抑制。

英文摘要：

Objective：To evaluate the activities of extracellular proteinase and serine protease secreted by Cryptococcus neoformans（C, neoformans） of different sources and serotypes and incubated under different conditions. Methods： Thirty-six C. neoformans strains of different sources and serotypes were incubated in protein agar medium at 30℃ and 37℃ separately. Activities of extracellular proteinase and serine protease were analyzed by determining Clearance Halos（CHs） produced by C. neoformans. Activity changes of the 2 proteases were analyzed after treated with serine protease inhibitors. The activity and the molecular weight of extracellular proteinase in the concentrated supernatant were measured using zymograpby assay. Results： Thirty-three of 36 C. neoformans strains produced specific Clearance Halos around the colonies, and their mean CHs at 30℃ and 37℃ were0.558±0.170 and0.575±0.169, respectively（P〉0.05）. The meanCHs of serotype A（n=13）, B（n=13）, and D/AD （n=6） strains were0.564±0. 144, 0.515±0.078 and 0.482±0.072, respectively（P〉0.05）; the mean CHs of clinical（n=23）, environmental（n=9）,and uncapsuled strains（n=4） were 0. 570±0. 177, 0. 513±0. 069, and 0. 942±0. 075, respectively（P〈0.05）. The mean CHs of control group （without protease inhibitor） and groups treated with protease inhibitor （1.2 mU and 1.6 mU） were 0. 459±0. 188, 0. 975±0. 287 and 0. 733±0. 252, respectively（P〈0.01）. Rich extracellular protease was found in the concentrated supernatant. Conclusion：The incubation temperature （30℃ and 37℃） has no effect on activities of extracellular proteinase and serine protease, and the activities of clinical strains are significantly stronger than those of other 2 strains; the activities in different serotypes groups have no significant difference and can be inhibited by serine protease inhibitors.