Biomaterial Database

Molecular studies of glycogen phosphorylase b from bovine liver. 1995

A C Artigas, and C Barón, and A Parody-Morreale

Departamento de Química-Física, Bioquímica y Química Inorgánica, Facultad de Ciencias Experimentales, Universidad de Almería, Spain.

Two active isoforms of bovine liver phosphorylase with distinct subunit composition have previously been purified (Cámara Artigas, A., Barón, C. and Parody-Morreale, A. Prot. Express. Purif. 1994, 5, 157), one showing three SDS-PAGE polypeptide bands (molecular mass = 97, 55 and 40 kDa) and the other showing just one (molecular mass = 97 kDa). A molecular mass of 200 kDa has been determined for the native enzymes by gel filtration. Amino acid analyses have been performed in both cases, giving the same results which are similar to those obtained with other phosphorylases. SDS-PAGE experiments at different concentrations of the three-band enzyme have suggested a 1:1:1 stoichiometry between the polypeptides. The pyridoxal-5'-phosphate site is located in the 55 kDa polypeptide and the phosphorylation site in the 40 kDa one. These polypeptides can be generated from the three-band enzyme by tryptic attack in the presence of glycogen without loss of enzyme activity. In the absence of glycogen, 55 kDa and 38 kDa polypeptides are generated, with a significant decrease in activity. We conclude that the three-band enzyme is a dimer composed of an intact monomer and a broken one. The lyotropic salt activation site of the enzyme is near the amino terminal group.

UI	MeSH Term	Description	Entries
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
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D011489	Protein Denaturation	Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.	Denaturation, Protein,Denaturations, Protein,Protein Denaturations
D011732	Pyridoxal Phosphate	This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).	Pyridoxal 5-Phosphate,Pyridoxal-P,Phosphate, Pyridoxal,Pyridoxal 5 Phosphate,Pyridoxal P
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
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D006005	Phosphorylases	A class of glucosyltransferases that catalyzes the degradation of storage polysaccharides, such as glucose polymers, by phosphorolysis in animals (GLYCOGEN PHOSPHORYLASE) and in plants (STARCH PHOSPHORYLASE).	Glucan Phosphorylase,Phosphorylase,alpha-Glucan Phosphorylases
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