Last modified: Fri Jul 9 14:29:23 BST 2004

Steroid carbon nomenclature

Trivial name: 11ß-Hydroxyprogesterone
Systematic name: 11ß-Hydroxypregn-4-ene-3,20-dione
Molecular formula: C21H30O3
CAS Number: 600-57-7

Substrate [1]

11ß-Hydroxyprogesterone -> 11ß,14alpha-Dihydroxyprogesterone
Reaction: steroid alpha-hydroxylation at C14
Enzyme: Cochliobolus lunatus P450C.l. (progesterone 14alpha-hydroxylase)

Substrate [2]

Pathway: 11ß-Hydroxyprogesterone -> 21-Deoxycortisol
Reaction: steroid alpha-hydroxylation at C17
Enzyme: P450c17 (steroid 17alpha-hydroxylase/17,20-lyase), CYP17

Substrate [2]

Pathway: 11ß-Hydroxyprogesterone -> Corticosterone
Reaction: steroid hydroxylation at C21
Enzyme: P450c21 (steroid 21-hydroxylase), CYP21A


Pathway: Progesterone -> 11ß-Hydroxyprogesterone
Reaction: steroid ß-hydroxylation at C11
Enzyme: P450c11 (steroid 11ß-hydroxylase), CYP11B [2]
EC Enzyme: Cochliobolus lunatus P450C.l. (progesterone 11ß-hydroxylase) [1]


  1. Vitas, M., Rozman, D., Komel, R. and Kelly, S.L. (1995) P450 mediated progesterone hydroxylation in Cochliobolus lunatus. J. Biotechnol. 42, 145-150.
  2. Ruckpaul, K. and Rein, H., Eds. (1990) Frontiers in Biotransformation, vol. 3: Molecular Mechanisms of Adrenal Steroidogenesis and Aspects of Regulation and Application. Taylor & Francis, London.

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