Development and evaluation of a whole-cell system for the directed evolution of human cytochromes P450 in recombinant fission yeast Schizosaccharomyces pombe

Cytochromes P450 catalyse a diversity of reactions on a vast variety of substrates and are, therefore, of great biotechnological impact. However, especially eukaryotic P450s very often show low activities so that improvements are necessary for successful biotechnological application. Previous studies reported fission yeast Schizosaccharomyces pombe as an excellent model organism for the expression of human cytochromes P450. Therefore, the purpose of this work was to develop a yeast whole-cell screening system for the directed evolution of the mitochondrial cytochrome P450 CYP11B2 to improve its catalytic activity. The development of the yeast whole-cell screening system was demonstrated and mutants with up to 8-fold improved activity of CYP11B2-dependent 11-deoxycorticosterone conversion have been obtained. The obtained clones can directly be used for biotechnological applications of fission yeast demonstrating the efficiency of the developed method.