Cytochrome P450 102A2 Catalyzes Efficient Oxidation of Sodium Dodecyl Sulphate: A Molecular Tool for Remediation

摘要

Bacterial cytochrome P450s (CYPs) constitute an important family of monooxygenase enzymes that carry out essential roles in the metabolism of endogenous compounds and foreign chemicals. In the present work we report the characterization of CYP102A2 fromB. subtiliswith a focus on its substrate specificity. CYP102A2 is more active in oxidation of sodium dodecyl sulphate (SDS) than any other characterized CYP. The effect of SDS and NADPH concentration on reaction rate showed nonhyperbolic and hyperbolic dependence, respectively. The enzyme was found to exhibit a bell-shaped curve for plots of activity versus pH, over pH values 5.9–8.5. The rate of SDS oxidation reached the maximum value approximately at pH 7.2 and the pH transition observed controlled by two pKas in the acidic(pKa=6.7±0.08)and basic(pKa=7.3±0.06)pH range. The results are discussed in relation to the future biotechnology applications of CYPs.