蛋白质谷氨酰胺酶的发酵及初步分离和应用研究

研究了不同发酵条件对于产吲哚金黄杆菌（Chryseobacterium indologenes）生产蛋白质谷氨酰胺酶能力的影响，酶的分离和初步的应用。通过考察种子的生长曲线，发酵的温度、转速、摇瓶装液量，碳源和氮源，得出最大产酶能力的发酵条件为：30℃，200r/min，装液量25ml/250ml，蔗糖为碳源，多聚蛋白胨为氮源，发酵10~12h。初步分离研究表明在4倍超滤浓缩和4倍乙醇沉淀条件下，酶活力回收率均为最高，分别为84.99%和76.07%。该酶与酪蛋白37℃温育2h时，酪蛋白的脱酰胺度为41.03%，到24h后，脱酰胺度不再增加，并且酪蛋白的溶解性也有所增加。

Study on Fermentation,Extraction and Application of Protein-Glutaminase

Influence of different fermentation conditions of Chryseobacterium indologenes on its protein-glutaminase producing ability, the extraction and application of enzyme were studied. The optimal fermentation condition was concluded from the studies of seed culture profile, fermentation temperature, rotation speed, volume of medium, carbon source and nitrogen source. The result showed that the optimal fermentation condition was 30℃, 200r/min, 250ml shake flask with 25ml culture medium, sucrose as carbon source, poly-peptone as nitrogen source, fermenting for 10~12h. The study of preliminary extraction indicated that when the enzyme solution was 4-fold concentrated and precipitation with 4 times volume of ethanol, the maximum of total enzyme recovery of this two steps were both obtained, were 84.99% and 76.07%, respectively. When casein was incubated with the enzyme for 2h, deamidation degree of deamidated casein could reach 41.03%. After the incubation time of 24h, deamidation degree was no longer increase, and the solubility of casein improved.