研究了不同诱导条件对基因工程菌催化合成茶氨酸的影响,确定了较为优化的诱导表达条件;通过单因子试验研究了不同反应条件对基因工程菌催化合成茶氨酸的影响,研究结果表明反应体系中较高的菌体浓度对催化茶氨酸有一定的抑制作用;高L-Gln浓度可以提高茶氨酸的生成量,但是却降低了L-Gln的转化率;基因工程菌催化合成茶氨酸的最适pH是9.5左右,较为适合的反应温度是32℃~37℃。
Expression conditions of the genetic engineering E.coli which expressed E.coli γ-GGT were investigated. The optimum IPTG concentration and inductive temperature were determined. Factorial experiment design was employed to determine the effects of the reactive conditions (such as microbe concentration, pH, substitute concentration, reactive temperature) on theanine biosynthesis. Results showed that theanine biosynthesis was inhibited by the high microbe concentration. By the higher concentration of L-Gln, the more theanine was obtained and the convertion rate against Gln was declined. It also was manifested that pH9.5 and 32℃~37℃ were optimum conditions for theanine biosynthsis.
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