Isopropylmalate synthetase and application thereof

The invention relates to a 2-isopropylmalate synthetase for removing feedback inhibition of L-leucine and an application of the 2-isopropylmalate synthetase, and belongs to the field of metabolic engineering. The leuA gene coded 2-isopropylmalate synthetase has the following characteristics: the synthetase removes the feedback inhibition effect of the L-leucine on the synthetase; under the condition that the concentration of the L-leucine is 0-15 mmol/L, the LEUA activity is not obviously changed; the activity of the 2-isopropylmalate synthetase is not obviously reduced compared with that of a wild LeuA coded 2-isopropylmalate synthetase; and the 2-isopropylmalate synthetase can be applied to the production of the L-leucine. 本发明涉及一个解除L-亮氨酸反馈抑制的2-异丙基苹果酸合成酶及其应用，属于代谢工程领域。本发明所述leuA基因编码的2-异丙基苹果酸合成酶具有如下特点：该酶解除了L-亮氨酸对其的反馈抑制作用，在L-亮氨酸浓度为0-15mmol/L条件下，LEUA酶活性无显著变化，且其活性较野生型leuA编码的2-异丙基苹果酸合成酶未见明显降低，可应用于L-亮氨酸中的生产。