A Fungal P450 from Thanatephorus cucumeris with Novel Steroid Hydroxylation Capabilities.

In this study, we identified a P450 enzyme (STH10) and an oxidoreductase (POR) from Thanatephorus cucumeris NBRC 6298 by a combination of transcriptome sequencing and heterologous expression in Pichia pastoris The biotransformation of 11-deoxycortisol was performed by using the Pichia pastoris whole cells co-expressing sth10 and por, and the product analysis indicated that the STH10 enzyme possessed steroidal 19- and 11β-hydroxylase activities. This is a novel fungal P450 enzyme with 19-hydroxylase activity, which is different from the known steroidal aromatase CYP19 and CYP11B families of enzymes.IMPORTANCE Hydroxylation is one of the most important reactions in steroid functionalization, especially C19-hydroxylation produces a key intermediate for the synthesis of 19-nor-steroid drugs without C19 angular methyl group in three chemo-enzymatic steps, instead of the current industrial process with ten chemical reactions. However, hydroxylation of the C19 angular methyl group remains a very challenging task due to the large steric resistance to the 19 methyl group between the A and B rings. The present study reports a novel fungal P450 enzyme with 19-hydroxylase activity. This opens a new venue for searching effective biocatalysts for the useful steroidal C-19 hydroxylation, although further studies for better understanding of the structural basis underlying regioselectivity and substrate specificity of this fungal steroidal 19-hydroxylase is warranted to facilitate the engine...
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Tags: Appl Environ Microbiol Source Type: research