球孢白僵菌几丁质酶的定位研究

采用酶解球孢白僵菌菌丝细胞壁以获得原生质体,用超声破碎器破碎细胞,并用差速离心等方法,对此丝状病原真菌细胞中几丁质酶的定位进行了研究.采用球孢白僵菌 Eu-120株,分别用几丁质酶、蜗牛酶和纤维素酶,以不同比例混合进行脱壁处理.通过测定培养物上清液及原生质体溶解物的几丁质酶活性,发现此培养物上清液中的酶活性占其总酶活性的81.46%,而原生质体溶解物中酶活性极少.研究表明,球孢白僵菌几丁质酶主要存在于细胞的周质空间,并在菌生长过程中通过细胞壁分泌至细胞外.

LOCALIZATION OF THE CHITINASE FROM THE FUNGUS BEAUVERIA BASSIANA

The localization of chitinase in the Beauveria bassiana EU-120 is studied by means of ultrasonic oscillation,differential centrifugation of my- celial homogenates and preparation of protoplasts.In order to obtain stable protoplasts the mycelitrm is treated with an incubation mixture containing chitinase,cullulase and as an osmotic stabilize 0.4mol/L NaCl in 0.15mol/L phosphate buffer pH5.5.The activity of chitinase is found essentially in the supernatant from culture solution,and very little in the mycelial cells,A conclusion is put forward that the chitinase seems to be located in the per- iplasma of Beauveria bassiana EU-120,and during the growth of the myceli- um it is excreted into the culture fluid.