嗜热蛋白酶生产菌的筛选

Screening of Thermophilic Proteinase Strain

从温泉水、高温堆肥等样品中初筛到62株嗜热蛋白酶生产菌,进一步复筛出一株高产嗜热蛋白酶的生产菌株DPE7(菌株来自温泉水),该菌株被初步鉴定为芽孢杆菌(Bacillus sp．)．嗜热蛋白酶生产的最适碳源是葡萄糖, 最佳氮源为酵母粉加硫酸铵,Ca2+对菌株产酶具有促进作用．在65℃、175 r／min、pH 9的产酶培养基中振荡培养 24 h后,发酵液中的酶产量高达23．4 U／mL(60℃测定)．

A high yield thermophilic proteinase strain was isolated from samples of hot spring. The strain was identified as Bacillus sp.. Suitable conditions have been studied for production of thermopbilic proteinase by Bacillus sp. DPE7, the best carbondrates is glucose, the optimum nitrogen source is yeast powder ＋ （NH4）2 SO4 and Ca^2＋ Can increase the enzyme product of the strain. The enzyme activity of supernatant is 23.4 U/mL（determined at 60 ℃） after Bacillus sp. was grown in the medium for producing proteinase for 24 h at 65 ℃, 175 r/min.