Immobilized glyceraldehyde-3-phosphate dehydrogenase forms a complex with phosphoglycerate kinase.
Yeast glyceraldehyde-3-phosphate dehydrogenase (GPDH) covalently attached to CNBr-activated Sepharose 4B was shown to be capable of binding soluble yeast phosphoglycerate kinase (PGK) in the course of incubation in the presence of an excess of 1,3-diphosphoglycerate. The association of the matrix-bound and soluble enzymes also occurred if the kinase was added to a reaction mixture in which the immobilized glyceraldehyde-3-phosphate dehydrogenase, NAD, glyceraldehyde-3-phosphate and Pi had been preincubated. Three kinase molecules were bound per a tetramer of the immobilized dehydrogenase and one molecule per a dimer. An immobilized monomer of glyceraldehyde-3-phosphate dehydrogenase was incapable of binding phosphoglycerate kinase. The matrix-bound bienzyme complexes were stable enough to survive extensive washings with a buffer and could be used repeatedly for activity determinations. Experimental evidence is presented to support the conclusion that 1,3-diphosphoglycerate produced by the kinase bound in a complex can dissociate into solution and be utilized by the dehydrogenase free of phosphoglycerate kinase.
D004800:Enzymes, Immobilized / Q000378:metabolism*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism*; D007700:Kinetics; D046911:Macromolecular Substances; D010735:Phosphoglycerate Kinase / Q000378:metabolism*; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
D004800:Enzymes, Immobilized; D046911:Macromolecular Substances; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D010735:Phosphoglycerate Kinase