To further enhance hydroxylation ability with indole of P450 BM-3,site-directed mutagenesis with V445A was introduced to the mutant D168L/E435T obtained in earlier research,and mutant D168L/E435T/ V445A was obtained.Compared with D168L/E435T and V445A,mutant D168L/E435T/V445A exhibited lower affinity with indole,but higher improved turnover rate(kcat).Correspondingly,catalytic efficiency(kcatKm -1) was increased to 1.53 times and 1.47 times respectively.The electronic coupling rate of the mutant was also im...