Krakhmaleva I N, Telesnina G N, Petiushenko R M
Antibiot Khimioter. 1988 May;33(5):327-30.
There were observed two pathways of glutamic acid formation in two strains of Acremonium chrysogenum differing in the production levels of cephalosporin C. The pathway involving glutamate dehydrogenase is known. The other pathway involved amination catalyzed by glutamine synthetase. Activity of both the enzymes during intensive synthesis of the antibiotic was higher in the highly productive strain. Under conditions of limited nitrogen content in the medium production of glutamate during the antibiotic biosynthesis depended on glutamine synthetase. When there was an excess of nitrogen in the medium the main role in production of glutamic acid at the phase of cephalosporin synthesis was played by the other enzyme i. e. glutamate dehydrogenase. By the dynamics the curve of the glutamate dehydrogenase activity correlated with that of the antibiotic production.
在两株头孢菌素C产量水平不同的产黄顶孢霉中观察到了谷氨酸形成的两条途径。涉及谷氨酸脱氢酶的途径是已知的。另一条途径涉及谷氨酰胺合成酶催化的胺化作用。在抗生素大量合成过程中,这两种酶的活性在高产菌株中更高。在培养基中氮含量有限的条件下,抗生素生物合成过程中谷氨酸的产生取决于谷氨酰胺合成酶。当培养基中氮过量时,在头孢菌素合成阶段谷氨酸产生中起主要作用的是另一种酶,即谷氨酸脱氢酶。从动态来看,谷氨酸脱氢酶活性曲线与抗生素产量曲线相关。