dtsR1基因缺失对谷氨酸发酵的影响

Effects of dtsR1 Gene Deletion on the Glutamate Fermentation

利用基因敲除的方法将野生型谷氨酸棒状杆菌(Corynebacterium glutamicum)定向缺失dtsR1基因,构建△dtsR1突变菌株,分析其在无诱导条件、添加吐温-40及生物素限制条件下菌体的生长和谷氨酸生产情况,并与野生型谷氨酸棒状杆菌在相同的发酵条件下进行比较。结果发现,在无诱导条件下,△dtsR1突变菌株能够引发谷氨酸的合成,而野生型谷氨酸棒状杆菌不分泌谷氨酸。在添加吐温-40及生物素限制条件下,△dtsR1突变菌株的谷氨酸产量明显高于无诱导条件下的谷氨酸产量。dtsR1基因的缺失提高了菌株的生长与谷氨酸合成的能力,在无诱导条件下也能促使谷氨酸的合成。

Wild-type Corynebacterium glutamicttm strain was selected and knocked dtsR1 gere. The growth and glutamate pro-duction of AdtsR1 mutant and wild-type strain were analyzed by glutamate fermentation under non-inducing, addition of Tween-40 or biotin limitation conditions. Data showed that glutamate synthetized was detected by △dtsR1 mutant under non-inducing conditions; however, wild-type strain did not secret glutamate at all. The amount of glutamate produced by the △dtsR1 mutant was much more than that of wild-type strain under addition of Tween-40 or biotin limitation conditions. It was concluded that deletion of dtsR1 gene could elevate the growth and glutamate production even in the absence of any in-ducing conditions.