Biomaterial Database

Competitive inhibition of cytochrome P-450scc by (22R)- and (22S)-22-aminocholesterol. Side-chain stereochemical requirements for C-22 amine coordination to the active-site heme. 1985

A Nagahisa, and T Foo, and M Gut, and W H Orme-Johnson

Two diastereomeric aminocholesterols, (22R)-22-aminocholesterol and (22S)-22-aminocholesterol, are both found to be potent inhibitors of the biosynthesis of pregnenolone from cholesterol by purified bovine mitochondrial P-450scc. Both steroids are competitive versus cholesterol, but the stereochemically correct analog (22R)-22-aminocholesterol is bound approximately 1000 times more tightly than (22S)-22-aminocholesterol. The dissociation constants are 25 nM and 13 microM, respectively. Direct comparisons between spectroscopic and enzymatic properties of the two enzymesterol complexes and the 22-amino-23,24-bisnor-5-cholen-3 beta-ol complex are made, underlining the importance of the stereochemistry at the C-22 position.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D006418	Heme	The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.	Ferroprotoporphyrin,Protoheme,Haem,Heme b,Protoheme IX
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D013053	Spectrophotometry	The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
D013237	Stereoisomerism	The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)	Molecular Stereochemistry,Stereoisomers,Stereochemistry, Molecular,Stereoisomer
D065607	Cytochrome P-450 Enzyme Inhibitors	Drugs and compounds which inhibit or antagonize the biosynthesis or actions of CYTOCHROME P-450 ENZYMES.	Cytochrome P-450 Inhibitors,Cytochrome P-450 Monooxygenase Inhibitors,Cytochrome P-450 Oxygenase Inhibitors,Cytochrome P-450-Dependent Monooxygenase Inhibitors,P-450 Enzyme Inhibitors,P450 Enzyme Inhibitors,Cytochrome P 450 Dependent Monooxygenase Inhibitors,Cytochrome P 450 Enzyme Inhibitors,Cytochrome P 450 Inhibitors,Cytochrome P 450 Monooxygenase Inhibitors,Cytochrome P 450 Oxygenase Inhibitors,Enzyme Inhibitors, P-450,Enzyme Inhibitors, P450,Inhibitors, Cytochrome P-450,Inhibitors, P-450 Enzyme,Inhibitors, P450 Enzyme,P 450 Enzyme Inhibitors,P-450 Inhibitors, Cytochrome