Fig. 1From: Identification, function, and application of 3-ketosteroid Δ1-dehydrogenase isozymes in Mycobacterium neoaurum DSM 1381 for the production of steroidic synthonsAn overview of proposed pathway for phytosterols degradation in mycobacteria. Phytosterols can be transformed to vary valuable intermediates, including C19-steroids (4-androstene-3,17-dione [AD], 1,4-androstadiene-3,17-dione [ADD], and 9α-hydroxy-4-androsten-3,17-dione [9-OHAD]) and C22-steroids (22-hydroxy-23, 24-bisnorchola-4-en-3-one [4HP], 22-hydroxy-23, 24-bisnorchola-1,4-dien-3-one [HPD] and 9,22-dihydroxy-23,24-bisnorchol-4-ene-3-one [9-OHHP]). KstD, 3-ketosteroid-Δ1-dehydrogenase; KSH, 3-ketosteroid-9α-hydroxylases; CYP125, cytochrome P450 125; CHO, cholesterol oxidase; Hsd4A, 17β-hydroxysteroid dehydrogenase and β-hydroxyacyl-CoA dehydrogenase; FadA5, thiolase FadA5Back to article page