Biomaterial Database

17beta-Hydroxy-C19-steroid dehydrogenases from male guinea pig liver. Purification and characterization. 1978

K Kobayashi, and C D Kochakian

One major and six minor 17beta-hydroxy-C19-steroid dehydrogenases were isolated each in a highly pure form from male adult guinea pig liver by a combination of gel filtration and ion exchange chromatography. Molecular weight, amino acid composition, sugar content, number of sulfhydryl groups. NH2-terminal amino acid, isoelectric point, substrate specificity, pH optima, Km values, and inhibitory effect of other steroids were studied. The amino acid composition, Km values, and substrate specificity indicated two separate groups of enzymes. The first group possessed a dual coenzyme requirement and specificity for 5beta-androstanes, whereas the second group showed apparent TPN+ and 5alpha-androstane specificities. Phosphate enhanced the DPN+-related activity of the first group and evoked DPN+-linked activity in the second group of enzymes. A molecular weight of 31,000 to 32,000 with a single chain structure was estimated for four of the enzymes. The other three enzymes consisted of two components of 24,000 and 11,000 daltons.

UI	MeSH Term	Description	Entries
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008297	Male		Males
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
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
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities
D015067	17-Hydroxysteroid Dehydrogenases	A class of enzymes that catalyzes the oxidation of 17-hydroxysteroids to 17-ketosteroids. EC 1.1.-.	17 beta-Hydroxysteroid Dehydrogenases,Testosterone Dehydrogenases,17-Ketosteroid Reductases,17 Hydroxysteroid Dehydrogenases,17 Ketosteroid Reductases,17 beta Hydroxysteroid Dehydrogenases,Dehydrogenases, 17 beta-Hydroxysteroid,Dehydrogenases, 17-Hydroxysteroid,Dehydrogenases, Testosterone,Reductases, 17-Ketosteroid