Switching the regioselectivity of two nitrilases toward succinonitrile by mutating the active center pocket key residues through a semi-rational engineering.

The 163Ala in bll6402NIT and 172Trp in blr3397NIT played a significant role in directing nitrilase regioselectivity. Amino acid mutation of two nitrilases at these two sites could alter the size of the active site pocket and further switch nitrilase regioselectivity toward succinonitrile, which lays the foundation for subsequent research on regioselective nitrilase towards several dinitriles.