Preparation of a whole cell catalyst overexpressing acetohydroxyacid synthase of Thermotoga maritima and its application in the syntheses of α-hydroxyketones

• Published in: Scientific reports 2020-09, Vol.10 (1), p.15404-15404, Article 15404
• Main Authors: Liang, Yan-Fei, Yan, Le-Tian, Yue, Qiao, Zhao, Ji-Kui, Luo, Cai-Yun, Gao, Feng, Li, Heng, Gao, Wen-Yun
• Format: Article
• Language: English
• Subjects: 631/45/603; 631/45/607; 631/92/603; Acetolactate Synthase - isolation & purification; Acetolactate Synthase - metabolism; Catalysis; Catalytic Domain; Humanities and Social Sciences; Ketones; multidisciplinary; Recombinant Proteins - isolation & purification; Science; Science (multidisciplinary); Thermotoga maritima - metabolism
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-72416-6

The large catalytic subunit of acetohydroxyacid synthase (AHAS, EC 2.2.1.6) of Thermotoga maritima (TmcAHAS) was prepared in this study. It possesses high specific activity and excellent stability. The protein and a whole cell catalyst overexpressing the protein were applied to the preparation of α-hydroxyketones including acetoin (AC), 3-hydroxy-2-pentanone (HP), and ( R )-phenylacetylcarbinol ( R- PAC). The results show that AC and HP could be produced in high yields (84% and 62%, respectively), while R -PAC could be synthesized in a high yield (about 78%) with an R / S ratio of 9:1. Therefore, TmcAHAS and the whole cell catalyst overexpressing the protein could be practically useful bio-catalysts in the preparation of α-hydroxyketones including AC, HP, and R -PAC. To the best of our knowledge, this is the first time that bacterial AHAS was used as a catalyst to prepare HP with a good yield, and also the first time that TmcAHAS was employed to synthesize AC and R -PAC.