Abstract:
Cytochrome P450 monooxygenases (P450s) are heme-thiolate enzymes and play
an important role in the primary and secondary metabolism of living organisms. Genome
sequencing analysis of fungal organisms revealed the presence of numerous P450s in
their genomes, with few exceptions. P450s in the fungal subphylum Saccharomycotina,
which contains biotechnologically important and opportunistic human pathogen yeasts,
have been underexplored because there are few P450s in their genomes. In the present
study we performed comparative analysis of P450s in 25 yeast species. A hundred and
seventy-two P450s were found in 25 yeast species and these are grouped into 13 P450
families and 27 subfamilies. P450s ranged from a minimum of three (Saccharomyces
species) to a maximum of 21 (Candida species) in the yeast genomes. Among the P450
families, the CYP52 family showed the highest number of member P450s (71) followed by
CYP51 (27), CYP61 (25), CYP56 (20) and CYP501 (11). Pichia pastoris and Dekkera
bruxellensis showed a novel P450 family, CYP5489, in their genome. Based on the
functional properties of characterized P450s, we conclude that P450s in Saccharomycotina
species possibly play a role in organisms’ physiology either in the synthesis of cellular
components or in the utilization of simpler organic molecules. The ecological niches of
yeast species are highly enriched with simpler organic nutrients and it is well known
that yeast species utilize simpler organic nutrients as carbon source efficiently. This
might have played a role in compacting yeast genomes and possibly losing a considerable
number of P450s during evolution.
