The CYP52A subfamily of the alkane-assimilating yeast Candida maltosa consists of six structurally related isoforms. Four of them (CYP52A3, 4, 5, and 9) are strongly induced by alkanes and play an important role for the conversion of various alkanes and fatty acids. Taking advantage of a homologous overexpression system, we found in the present study that both of the two other CYP52A forms, CYP52A10 and CYP52A11, represent specialists for the hydroxylation of lauric acid suggesting their preference for short-chain fatty acids. At the same time, they hydroxylated palmitic acid only moderately and failed to convert hexadecane. Based on the now completed knowledge about the principal substrate specificities of all members of the CYP52A subfamily of C. maltosa, it became apparent that evolutionarily more distantly related P450 forms developed either to alkane or to fatty acid hydroxylases, whereas P450 forms which retained the ability to convert both types of substrates were also found to be evolutionarily related to both alkane and fatty acid hydroxylases.
Copyright 1998 Academic Press.