Cloned (Comment) | Organism |
---|---|
mutants and wild-type expressed in Escherichia coli | Bos taurus |
Protein Variants | Comment | Organism |
---|---|---|
K103Q | expression similar to wild-type, decreased stability or an altered heme or substrate pocket, B'-C loop, no change in interaction of P-450scc and adrenodoxin | Bos taurus |
K104Q | decreased expression, B'-C loop, no change in interaction of P-450scc and adrenodoxin | Bos taurus |
K109Q | change in folding, thus, an inability of heme to be retained, helix C, no change in interaction of P-450scc and adrenodoxin | Bos taurus |
K110Q | expression similar to wild-type, helix C, does not appear to play a role in adrenodoxin binding because it shows no change in interaction of P-450scc and adrenodoxin | Bos taurus |
K145Q | expression similar to wild-type, helix D | Bos taurus |
K148Q | extremely unstable, helix D | Bos taurus |
K338Q | removed from heme group but still very important for interaction with adrenodoxin, K helix | Bos taurus |
K342Q | removed from heme group but still very important for interaction with adrenodoxin, K helix | Bos taurus |
K394Q | expression similar to wild-type, "meander", involved in the interaction of P-450scc with its electron-transfer partners | Bos taurus |
K403Q | expression similar to wild-type, located between the meander and the heme-binding region, important role in electrostatic interactions with adrenodoxin, ability to bind adrenodoxin affected to lower extent than K405Q | Bos taurus |
K405Q | expression similar to wild-type, 4fold decrease in efficiency of enzymatic reduction by adrenodoxin and adrenodoxin reductase, and a 3.3fold decrease of cholesterol side chain cleavage activity, located between the meander and the heme-binding region, important role in electrostatic interactions with adrenodoxin | Bos taurus |
additional information | site directed mutagenesis. complex stabilizing salt bridges: K403 of P-450scc with D76 of adrenodoxin, K405 with D72, R426 with E73 and K267 with E47, multiple electrostatic interactions between the negatively charged residues of adrenodoxin and positively charged groups of P-450scc | Bos taurus |
R425Q | most harmful substitution, L helix, heme-binding region | Bos taurus |
R425Q/R426C | double mutant, most harmful substitution | Bos taurus |
R425Q/R426Q | double mutant, most harmful substitution | Bos taurus |
R426Q | expression similar to wild-type, serious changes in proteine folding and ability to insert and bind heme correctly, unable to catalyze cholesterol side chain cleavage reaction, although it is able to bind cholesterol, L helix, heme-binding region, important role in electrostatic interactions with adrenodoxin | Bos taurus |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
mitochondrial inner membrane | inner membrane | Bos taurus | 5743 | - |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
cholesterol + 6 reduced adrenodoxin + 3 O2 | Bos taurus | - |
pregnenolone + 4-methylpentanal + 6 oxidized adrenodoxin + 4 H2O | precursor of all steroid hormones | ? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Bos taurus | - |
- |
- |
Purification (Comment) | Organism |
---|---|
precipitation with polyethylene glycol, affinity chromatography | Bos taurus |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
adrenal cortex | - |
Bos taurus | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
cholesterol + 6 reduced adrenodoxin + 3 O2 | - |
Bos taurus | pregnenolone + 4-methylpentanal + 6 oxidized adrenodoxin + 4 H2O | precursor of all steroid hormones | ? | |
cholesterol + reduced adrenodoxin + O2 | - |
Bos taurus | pregnenolone + 4-methylpentanal + oxidized adrenodoxin + H2O | - |
? | |
additional information | 2 interaction processes with 2 different sensitivities to ionic strength | Bos taurus | ? | - |
? |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.2 | - |
assay at | Bos taurus |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
adrenodoxin | electron shuttle | Bos taurus | |
NADPH | - |
Bos taurus |