C-5 sterol desaturase

C-5 sterol desaturase (also known as sterol C-5 desaturase and C5SD) is an enzyme that is highly conserved among eukaryotes and catalyzes the dehydrogenation of a C-5(6) bond in a sterol intermediate compound as a step in the biosynthesis of major sterols. The precise structure of the enzyme's substrate varies by species. For example, the human C-5 sterol desaturase (also known as lathosterol oxidase) oxidizes lathosterol, while its ortholog ERG3 in the yeast Saccharomyces cerevisiae oxidizes episterol.[1][2]

The precise structural details of C-5 sterol desaturase substrates vary across eukaryotes. Shown below the reaction scheme are three possible distal groups along with biosynthetic pathways and species they are found in.[1][2][3]
  1. ^ a b Cite error: The named reference Osumi et al., 1979 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Kawata et al., 1985 was invoked but never defined (see the help page).
  3. ^ Choe Sunghwa; Noguchi Takahiro; Fujioka Shozo; Takatsuto Suguru; Tissier Christophe P; Gregory Brian D; Ross Amanda S; Tanaka Atsushi; Yoshida Shigeo; Tax Frans E; et al. (1999). "The Arabidopsis dwf7/ste1 mutant is defective in the delta 7 sterol C-5 desaturation step leading to brassinosteroid biosynthesis". The Plant Cell. 11 (2): 207–221. doi:10.1105/tpc.11.2.207. PMC 144158. PMID 9927639.