中文摘要：

钝齿棒杆菌（Corynebacterium crenatum）AS.M7是筛选获得的一株高产精氨酸生产菌株。ArgR是精氨酸合成过程中的一种调控蛋白。为进一步验证其在钝齿棒杆菌中对精氨酸合成量的影响,利用特异性引物,分别扩增标准菌C.creantum AS 1.542和诱变菌C.creantum AS.M7的argR全长基因,测序后比较二者的差异;结果表明标准菌argR基因ORF全长516 bp,编码一个含172个氨基酸残基的蛋白;而诱变菌argR基因的109位碱基由C替换为T,导致ArgR蛋白在钝齿诱变菌中表达被提前终止。同时,将来源于标准菌的argR基因连接到穿梭表达载体pXMJ19中,电击转化至诱变菌C.crenatum AS.M7得到重组菌株,用摇瓶发酵的方法观测重组菌产精氨酸量的变化。SDS-PAGE和Western blot分析证明标准菌的argR基因在诱变菌中得到了表达。对重组诱变菌产精氨酸量进行了测定,结果显示：产精氨酸能力由原来7.8 mg/ml下降至2.5mg/ml,下降了约67.9%。

英文摘要：

Corynebacterium crenatum AS.M7,mutated and stored is a high arginine producing strain.ArgR is one of the most important regulating proteins during arginine biosynthesis.To further confirm the effect of ArgR on arginine biosynthesis in C.crenatum,specific primers were designed and used for PCR amplification of full argR gene from wild strain C.crenatum AS 1.542 and a mutant strain C.creantum AS.M7.The amplified argR gene were aligned and compared for difference.Result showed that argR from C.crenatum AS 1.542 has ORF of 516 bp,encoding a protein consists of 172 amino acids.In comparison,argR from C.crenatum AS.M7 has a C instead of T on position 109,resulting termination of ArgR expression in C.crenatum AS.M7.Meanwhile,argR gene from C.crenatum AS 1.542 was cloned into pXMJ19 vector and transformed into C.crenatum AS.M7 to form a recombinant strain.Arginine production with recombinant strain was evaluated by fermentation in triangle flask.SDS-PAGE and Western blot were used for argR gene expression analysis,result showed a decrease of arginine production from 7.8 mg/ml to 2.5 mg/ml（appr.67.9%）.