Expression of the Curvularia sp. P450 Monooxygenase Gene in Escherichia coli and Confirmation of Its 7-Hydroxylation Function

Abstract

The diversity and uniqueness of fungal cytochromes P450 (CYP), capable of catalyzing the regio- and stereospecific hydroxylation of steroids, makes them important for microbiological synthesis of valuable hydroxysteroids. In the present work, the function of recombinant fungal P450 monooxygenase (CYPI) of Curvularia sp. strain VKM F-3040, a promising biocatalyst of 7-hydroxylation of androstane steroids, was studied. RT-PCR amplification of cDNA of the candidate CYPI gene and of the gene of its natural redox partner (POR), their cloning and heterologous expression in the cells of E. coli BL 21 DE(3) was carried out. In vitro experiments showed the ability of the obtained recombinant monooxygenase to catalyze hydroxylation of dehydroepiandrosterone at positions 7α and 7β. Our results expand the knowledge about fungal steroid hydroxylases and open up the prospects for the synthesis of valuable 7-hydroxysteroids by using recombinant producers.