Cholesterol to cholestenone oxidation by ChoG, the main extracellular cholesterol oxidase of Rhodococcus ruber strain Chol-4.

•Several putative cholesterol oxidase genes have been found in the genome of R. ruber.•ChoG is the only cholesterol oxidase that transforms cholesterol to cholestenone outside the cell.•The choG basal transcription levels are increased after induction with cholesterol.•The choG mutant strain displays a slower growth rate in cholesterol compared to the WT.•Cholestenone accumulation observed in cultures of R. ruber WT does not occur in the choG mutant.