3.7.1.8 - 3.7.1.8 2 isofunctional hydrolases H1 and H2 3.7.1.8 BphD mutants purified by affinity chromatography to more than 95% homogeneity 3.7.1.8 by metal affinity chromatography 3.7.1.8 by metal affinity chromatography, to more than 90% homogeneity 3.7.1.8 gel filtration, to homogeneity 3.7.1.8 MhpC mutants purified by anion exchange chromatography to more than 95% homogeneity 3.7.1.8 recombinant His-tagged wild-type and mutant enzymes from Escherichia coli strain BL21(DE3) by nickel affinity chromatography 3.7.1.8 standard method 3.7.1.8 to apparent homogeneity 3.7.1.8 to more than 90% homogeneitiy 3.7.1.8 to more than 99% homogeneity