L-谷氨酸氧化酶产生菌的筛选与产酶条件

SCREENING OF L-GLUTAMATE OXIDASE FORMING STRAINS AND CONDITIONS FOR ENZYME PRODUCTION

L-氨基酸氧化酶早就从鼠肾、蛇毒液、无脊椎动物和微生物等不同来源中分离得到,能够使多种氨基酸氧化脱氨却几乎不作用于 L-谷氨酸。最近从微生物中发现了一种新酶——L-谷氨酸氧化酶(E.C.1.4.3.11),能专一地催化下述反应:L-谷氨酸+O_2+H_2O→α-酮戊二酸+NH_3+H_2O_2 虽然还不清楚有较高底物专一性的 L-氨基酸氧化酶的生物学意义,但该酶是一种有价值的工具酶,可以用于分析 L-谷氨酸及与之偶联的许多化合物,因而受到重视。在临床上可用于测定血液中谷草转氨酶(GOT)、谷丙转氨酶(GPT)和γ-谷氨酰转移酶(γ-GTP)等。此外还可用于评价食品的质量、监测谷氨酸发酵等生产过程.本文报道了从土样中筛选到 L-谷氨酸氧化酶产生菌和诱导产酶条件的研究结果。

A strain P-26 producing extracellular L-glutamate oxidase was screened out from 125 Actinomyces.The formation of enzyme was induced by L-glutamate,it reached maximum when the microorganism was grown in wheat bran medium containing 0.2% L-glutamate, 0.5% Na_2CO_3 and 100% H_2O at 28℃ for 6 days.The enzyme activity could be moderately enhanced by extra supplement of inorganic salts such as MgSO_4.7H_2O and CaCl_2.