摘要
本文报道了用海藻酸钙凝胶包埋法制备固定化谷氨酸棒杆菌T6-13原生质体及其用于生产谷氨酸脱氢酶（GDH,E.C.1.4.1.4）的研究。在一定条件下游离细胞和固定化细胞胞内可积累谷氨酸脱氢酶,但并不分泌到胞外。对数生长前期的细胞经蛋清溶菌酶处理14h后分离得到原生质体,游离原生质体和固定化原生质体可产胞外GDH。用3%海藻酸钙凝胶包埋10%的原生质体制备的固定化原生质体具有较高的产酶性,分批培养72h后发酵液中GDH活力可达到1.64×10-2u/ml;为游离细胞胞内产酶的205%。固定化原生质体可用溶菌酶处理固定化细胞而制得,与直接固定化原生质体制备的固定化原生质体具有同样的产酶能力,且制备方便。固定化原生质体可重复使用6批次（约18天）,且具有良好的贮藏稳定性。
In this paper the preparation of immobilized Corynebacterium glutamicum T6-13 protoplasts and their use in producing glutamate dehydrogenase(GDH, E.C. 1.4.1.4) were reported. Under optimal condition, the free cells and immobilized cells of Corynebacterium glutarnicum T6-13 could intracellularly accumulate GDH which could not be secreted. Protoplasts were prepared by treating cells at mid-exponential phase with lysozyme for 14h and then by separating them. Free protoplasts and immobilized protoplasts could extracellularly secrete GDH when cultured in the enzyme producing medium, It was found that GDH activity in broth could reacb 1.64×10^(-2)u/ml when the immobilized protoplasts prepared with 3% Ca-alginate gel and 10% protoplasts were cultured in the enzyme-producing medium. Their enzyme productivity wes 205% of that of free cells accumulating intrcelluar GDH. Immobilized protoplasts could be also prepared by treating immobilized whole cells with lysozyme and this metbod was more convenient than directive immobilization of protoplasts. The immobilized protoplasts could be repeatedly used for at least six batchs (about 18 days)and had good storage stability.
出处
《生物工程学报》
CAS
CSCD
北大核心
1993年第2期158-162,共5页
Chinese Journal of Biotechnology
基金
国家自然科学基金
关键词
原生质体
固定化
谷氨酸脱氢酶
Protoplasts
immobilization
Corynebacterium glutamicum
dehydrogenase
