FadD19 of Rhodococcus rhodochrous DSM43269, a steroid-coenzyme A ligase essential for degradation of C-24 branched sterol side chains.

ABSTRACT: The actinobacterial cholesterol catabolic gene cluster contains a subset of genes that encode β-oxidation enzymes with a putative role in sterol side chain degradation. We investigated the physiological roles of several genes, i.e., fadD17, fadD19, fadE26, fadE27, and ro04690DSM43269, by gene inactivation studies in mutant strain RG32 of Rhodococcus rhodochrous DSM43269. Mutant strain RG32 is devoid of 3-ketosteroid 9α-hydroxylase (KSH) activity and was constructed following the identification, cloning, and sequential inactivation of five kshA gene homologs in strain DSM43269. We show that mutant strain RG32 is fully blocked in steroid ring degradation but capable of selective sterol side chain degradation. Except for RG32ΔfadD19, none of the mutants constructed in RG32 revealed an aberran

SUBMITTER: Wilbrink MH 

PROVIDER: S-EPMC3127730 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature