固定化产氨短杆菌细胞合成辅酶A的研究

Studies on preparation of immobilized Brevibacterium ammoniagenes cells and synthesis of coenzyme A

目的利用固定化产氨短杆菌细胞合成辅酶A。方法使用卡拉胶、魔芋胶和刺槐豆胶为复合载体包埋产氨短杆菌细胞,正交试验确定凝胶配方;正交试验确定合成辅酶A的前体配方;同时考察不同pH、不同表面活性剂对固定化细胞合成辅酶A的影响。结果最佳的凝胶配方为:卡拉胶1.0%,魔芋胶0.4%,刺槐豆胶0.4%;最佳前体配方为:泛酸钙0.3%,半胱氨酸0.3%,ATP 2%;最适pH值为7.0;最适表面活性剂为苯扎溴铵,添加量为0.05%。固定化细胞重复使用8次后,合成辅酶A的活性仍保持在50%以上。结论用卡拉胶、魔芋胶和刺槐豆胶作为复合载体制备的固定化产氨短杆菌细胞,合成辅酶A的能力较高,稳定性较好,具有应用价值。

Purpose To prepare immobilized Brevibacterium ammoniagenes cells and to study the stability and the optimum conditions of synthesis of coenzyme A. Methods Carrageenan, konjac gum and robinia bean gum were used to prepare immobilized cells and their proportion was determined by orthogonal test. ATP, calcium pantothenate and cysteine were precursors of coenzyme A and their proportion was determined by orthogohal test. Furthermore, the effects of different pH and different surfactants were observed. Results The opti- mum conditions ： carrageenan 1.0 %, konjac gum 0.4 % and robinia bean gum 0.4 % , calcium pantothenate 0.3 % and cysteine 0.3 %, ATP 2 %, pH 7.0 and benzalkonium bromide 0.05 % . The ability which immobilized cells to synthesize coenzyme A left more than 50 % after reusing 8 times. Conclusion Carrageenan, konjac gum and robinia bean gum were good carriers to prepare immobilized cells of Brevibacterium ammoniagenes. Immobilized cells had high ability and good stability to synthesize coenzyme A.