ID   1.14.14.32
DE   17alpha-hydroxyprogesterone deacetylase.
AN   17alpha-hydroxyprogesterone 17,20-lyase.
AN   17alpha-hydroxyprogesterone acetaldehyde-lyase.
AN   CYP17.
AN   CYP17A1.
CA   (1) 17alpha-hydroxyprogesterone + O2 + reduced [NADPH--hemoprotein
CA   reductase] = acetate + androst-4-ene-3,17-dione + 2 H(+) + H2O + oxidized
CA   [NADPH--hemoprotein reductase].
CA   (2) 17alpha-hydroxypregnenolone + O2 + reduced [NADPH--hemoprotein
CA   reductase] = 3beta-hydroxyandrost-5-en-17-one + acetate + 2 H(+) + H2O +
CA   oxidized [NADPH--hemoprotein reductase].
CC   -!- A microsomal protein that catalyzes two independent reactions at the
CC       same active site - the 17-hydroxylation of pregnenolone and
CC       progesterone, which is part of glucocorticoid hormones biosynthesis
CC       (EC 1.14.14.19), and the conversion of the 17-hydroxylated products
CC       via a 17,20-lyase reaction to form androstenedione and 3beta-
CC       hydroxyandrost-5-en-17-one, leading to sex hormone biosynthesis.
CC   -!- The activity of this reaction is dependent on the allosteric
CC       interaction of the enzyme with cytochrome b5 without any transfer of
CC       electrons from the cytochrome.
CC   -!- The enzymes from different organisms differ in their substrate
CC       specificity; while the enzymes from pig, hamster, and rat accept both
CC       17alpha-hydroxyprogesterone and 17alpha-hydroxypregnenolone,
CC       the enzymes from human, bovine, sheep, goat, and bison do not accept
CC       the former, and the enzyme from guinea pig does not accept the
CC       latter.
CC   -!- Formerly EC 4.1.2.30.
DR   Q9GMC7, CP17A_BISBI;  P05185, CP17A_BOVIN;  Q9N0U7, CP17A_CAPHI;
DR   Q64410, CP17A_CAVPO;  P12394, CP17A_CHICK;  Q9GMC8, CP17A_FELCA;
DR   Q95328, CP17A_HORSE;  P05093, CP17A_HUMAN;  O73853, CP17A_ICTPU;
DR   Q2XVA1, CP17A_MACFA;  Q8HYM9, CP17A_MACMU;  P70687, CP17A_MESAU;
DR   P27786, CP17A_MOUSE;  P30437, CP17A_ONCMY;  P70085, CP17A_ORYLA;
DR   Q8HYN1, CP17A_PANTR;  Q8HYN0, CP17A_PAPCY;  Q9GLD2, CP17A_PAPHU;
DR   Q91Z85, CP17A_PERLE;  P19100, CP17A_PIG  ;  O57525, CP17A_RANDY;
DR   P11715, CP17A_RAT  ;  Q29497, CP17A_SHEEP;  Q92113, CP17A_SQUAC;
//