Phosphorylase: control and activity

1981 ◽  
Vol 293 (1063) ◽  
pp. 23-41 ◽  
Keyword(s):  
Lactate Dehydrogenase ◽  
Special Reference ◽  
Binding Sites ◽  
Glycogen Phosphorylase ◽  
Pyridoxal Phosphate ◽  
Potent Inhibitor ◽  
Structural Similarity ◽  
Mechanism Of Catalysis ◽  
Cyclic Phosphate

Recent results from the crystallographic studies on glycogen phosphorylase b at 3 A resolution are reviewed with special reference to other themes of the meeting. The structural similarity of the fold of 150 residues in phosphorylase to that observed in lactate dehydrogenase is discussed and the binding sites for NADH in phosphorylase are described. The binding of the potent inhibitor glucose-1,2-cyclic phosphate to phosphorylase b in the crystal has been studied at 3 A resolution. The results are compared with those previously obtained for glucose-1-phosphate and discussed with reference to proposals for a mechanism of catalysis that involves the essential cofactor pyridoxal phosphate.

scholarly journals The structure of glycogen phosphorylase b with an alkyldihydropyridine-dicarboxylic acid compound, a novel and potent inhibitor

Structure ◽  
1997 ◽  
Vol 5 (11) ◽  
pp. 1413-1425 ◽  
Author(s):  
Spyros E Zographos ◽  
Nikos G Oikonomakos ◽  
Katerina E Tsitsanou ◽  
Demetrios D Leonidas ◽  
Evangelia D Chrysina ◽  
...  
Keyword(s):  
Dicarboxylic Acid ◽  
Glycogen Phosphorylase ◽  
Potent Inhibitor ◽  
Compound A ◽  
Glycogen Phosphorylase B ◽  
Acid Compound

PYRIDOXAL PHOSPHATE ANALOGS AND COENZYME FUNCTION IN GLYCOGEN PHOSPHORYLASE

1978 ◽  
pp. 195-204 ◽  
Author(s):  
Donald J. Graves ◽  
Richard F. Parrish ◽  
Ronald J. Uhing ◽  
Walter Korytnyk
Keyword(s):  
Glycogen Phosphorylase ◽  
Pyridoxal Phosphate

scholarly journals Developmentally regulated enzymes and cyclic AMP-binding sites in Dictyostelium discoideum cells blocked during development by α-chymotrypsin

1982 ◽  
Vol 206 (2) ◽  
pp. 185-193
Author(s):  
J A Schmidt ◽  
J L Stirling
Keyword(s):  
Cyclic Amp ◽  
Dictyostelium Discoideum ◽  
Binding Sites ◽  
Glycogen Phosphorylase ◽  
Specific Activity ◽  
Tyrosine Aminotransferase ◽  
Carbohydrate Binding ◽  
Threonine Deaminase ◽  
Developmentally Regulated ◽  
Beta Glucosidase

When cells of the slime mould Dictyostelium discoideum are allowed to starve in the presence of alpha-chymotrypsin, they are blocked in development at the stage where tight aggregates form tips. Analysis of developmentally regulated enzymes has shown that alpha-mannosidase, beta-N-acetylglucosaminidase, threonine deaminase, tyrosine aminotransferase, beta-glucosidase and the carbohydrate-binding protein discoidin are unaffected, but enzymes that show an increase in specific activity during post-aggregative development, namely glycogen phosphorylase, UDP-glucose pyrophosphorylase, UDP-galactose 4-epimerase, UDP-galactose polysaccharide transferase and alkaline phosphatase, did not show the characteristic increase when development was blocked by alpha-chymotrypsin. Recovery of cells from the effects of alpha-chymotrypsin was accompanied by the formation of fruiting bodies and a concomitant increase in the specific activity of UDP-glucose pyrophosphorylase. Uptake or efflux of 45Ca2+ was not altered in the presence of alpha-chymotrypsin. Cells allowed to develop in alpha-chymotrypsin, or treated with the enzyme for 15 min, had a markedly reduced ability to bind cyclic AMP with low affinity; high-affinity binding was unaffected. Pronase had a similar effect on cyclic AMP binding, but trypsin, which does not alter developmental processes, has no effect on cyclic AMP binding to D. discoideum cells.

scholarly journals A quantitative study of the biospecific desorption of rat liver (M4) lactate dehydrogenase from 10-carboxydecylamino-Sepharose. Determination of the number of ligand-binding sites blocked on adsorption

1982 ◽  
Vol 207 (3) ◽  
pp. 549-556 ◽  
Author(s):  
P Kyprianou ◽  
R J Yon
Keyword(s):  
Lactate Dehydrogenase ◽  
Ligand Binding ◽  
Rat Liver ◽  
Binding Sites ◽  
Free Ligand ◽  
Factors Affecting ◽  
Adsorption Sites ◽  
Ligand Binding Sites ◽  
Chromatographic Parameters

1. The theory of Nichol, Ogston, Winzor & Sawyer [(1974) Biochem. J. 143, 435-443] for quantitative affinity chromatography, when adapted for use with a non-specific column from which a multi-site protein can be specifically desorbed by its free ligand, permits determination of the concentration of adsorption sites on the column, their adsorptive affinity (as an association constant) and either the intrinsic (site) constant for ligand-binding to the protein or an ‘occlusion coefficient’ (defined as the number of ligand-binding sites blocked on adsorption), one of which must be known. 2. The theory has been applied to the NADH-specific desorption of rat liver M4 lactate dehydrogenase from 10-carboxydecylamino-Sepharose. It suggests that most of the enzyme molecules are adsorbed with at least two NADH-binding sites blocked, indicating an extensive adsorption interface in relation to the protein surface. Other chromatographic parameters were also determined for the system. 3. Among topics discussed are (a) factors affecting the experimentally determined value for the number of blocked sites, (b) the nature of the adsorption sites on the column and (c) the similarity of the analysis to that for determining Hill coefficients, and other possible applications.

Sign in / Sign up

Export Citation Format

Share Document