Characterization of acid-resistant aldo–keto reductases capable of asymmetric synthesis of (R)-CHBE from Lactobacillus plantarum DSM20174

Ethyl (R)-4-chloro-3-hydroxybutyrate ((R)-CHBE), as a chiral intermediate, is widely used in the synthesis of various drugs. In this study, we screened two aldo–keto reductases (LP-AKRs) from probiotic Lactobacillus plantarum DSM20174, both with molecular weight approximately 31 kDa. Both enzymes could reduce 4-chloroacetoacetic acid ethyl ester (COBE) to produce (R)-CHBE an enantioselectivity value 99%. When determining kinetic parameter, Km, Kcat, and Vmax LP-AKR5 LP-AKR9 were 9.5 mM, 7.6 U/mg, 3.96 s−1 8.7 8.59 4.47 s−1, respectively. had optimal reaction pH 6 maintain high level stability at 6, allowing them perform well acidic environment. temperatures 30 °C 40 °C, Metal ions minimal influence on enzyme activities. This series enzymatic properties showed that mined DSM20174 asymmetrically catalyze under weakly circumstances, which product provide good foundation for industrial production.