嗜麦芽窄食单胞菌YJ-1角蛋白酶底物特性及酶活测定方法研究

Study on Substrate Characteristics and Activity Determination Method of Keratinase from Stenotrophomonas maltophilia Strain YHYJ-1

从羽毛加工厂污泥中分离到一株嗜麦芽窄食单胞菌(Stenotrophomonas maltophilia)YHYJ-1,对羽毛、羊毛和毛发底物均具有降解作用。菌株YHYJ-1对不同底物的降解能力存在差异,培养36 h羽毛完全降解,羊毛降解时间是72 h,毛发则在84 h有部分降解作用。分别以可溶性羽毛角蛋白、羽毛粉和偶氮角蛋白为底物进行酶活测定,以最高酶活值设定为100%,3种底物的相对酶活分别为100%、65.1%和23.2%,表明菌株YHYJ-1角蛋白酶的最适底物为可溶性角蛋白。菌株YHYJ-1接种于羽毛粉培养基,培养20 h后角蛋白酶活性急剧升高,28 h酶活达最大值,之后快速下降。

A Stenotrophomonas maltophilia strain YHYJ - 1 isolated from sludge of feather processing plant showed strong degrading capability on feather, wool and human hair. Feather and wool could be degrad- ed completely in 36 h and 72 h respectively, but only part of human hair could be degraded in 84 hours after incubated with YHYJ - 1. When co - incubated with substrates of soluble feather keratin, feather powder and azokeratin, the relative activity of keratinase were 100%, 65.1% and 23.2%, respectively, which indicated that soluble keratin was the optimal substrate. If incubated with feather meal, the keratinase activity increased sharply after incubated for 20 hours, and reached the highest after 28 hours, and then it decreased rapidly.