Abstract A temperature-sensitive mutant of Corynebacterium glutamicum is widely used as the fermentation strain in L-glutamate industrial production. Rapid synthesis of L-glutamate in this type of strain can be triggered by raising the culture temperature. However, the molecular mechanism of the temperature-sensitivity trait and L-glutamate excretion has not been clarified. In this study, we compared the genome sequence of an industrial L-glutamate-producing strain C. glutamicum TCCC11822 with the wild-type strain C. glutamicum ATCC13032. Seven mutant genes related to cell membrane synthesis were screened and separately integrated into the genome of C. glutamticum ATCC13032 to replace the corresponding genes. All the recombinant strains showed temperature-sensitivity and increased L-glutamate excretion. Electron microscopy showed that there was no significant change in cell morphology of recombinant strains at different temperatures. Genotypes found in this article can be applied to the construction of temperature-sensitive engineering strains and the regulation of cell permeability.

中文翻译：

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谷氨酸棒杆菌细胞膜合成基因突变导致温度敏感性状并促进L-谷氨酸排泄

摘要 谷氨酸棒状杆菌温度敏感突变体被广泛用作L-谷氨酸工业生产中的发酵菌株。提高培养温度可触发此类菌株中 L-谷氨酸的快速合成。然而，温度敏感性性状和L-谷氨酸排泄的分子机制尚未阐明。在这项研究中，我们比较了工业产 L-谷氨酸菌株 C. glutamicum TCCC11822 与野生型菌株 C. glutamicum ATCC13032 的基因组序列。筛选出7个与细胞膜合成相关的突变基因，分别整合到谷氨酸棒杆菌ATCC13032基因组中，替换相应基因。所有重组菌株均表现出温度敏感性和 L-谷氨酸排泄增加。电镜显示重组菌株在不同温度下细胞形态无明显变化。本文发现的基因型可应用于温度敏感工程菌株的构建和细胞通透性的调节。