Phosphoglycerate kinase, nucleotide

Kovari, Z. Flachner, B. Naray-Szabo, G. Vas, M. Crystallographic and thiol-reactivity studies on the complex of pig muscle phosphoglycerate kinase with ATP analogues correlation between nucleotide binding mode and helix flexibility. Biochemistry, 41, 8796-8806 (2002)... 

Reeves, R.E. South, D.J. Phosphoglycerate kinase (GTP). An enzyme from Entamoeba histolytica selective for guanine nucleotides. Biochem. Biophys. Res. Commun., 58, 1053-1057 (1974)... 

Direct measurement of enzyme-bound nucleotides with P-NMR confirmed this idea [175]. At a catalytic concentration of pyruvate kinase (or 3-phosphoglycerate kinase), the equilibrium constant of the reaction, is as low as 3 x 10 whereas the equilibrium constant for enzyme-bound ligands for both enzymes is 1. 

The conformations of nucleotides have been probed by lanthanides [73]. Furthermore, adenosine triphosphate (ATP)-lanthanide complexes are strong enough to carry the metal on to enzymes. Thus, Gd " competitively inhibits Mg -(yeast)-phosphoglycerate kinase (mol. wt. 47000) and selectively broadens histidine H resonances [74]. 

Fig. 14. Stereo views of various structures related to dehydrogenases by having similar nucleotide binding function and/or similar structures. Views are oriented as in Fig. 2 for the dehydrogenases, showing (a) flavodoxin, (b) adenylate kinase, (c) the ADP binding lobe of phosphoglycerate kinase, and (d) the central portion of subtilisin.

Mn -ATP (from a folded chelate to an extended outer-sphere complex) when the nucleotide binds to pyruvate kinase. It has also been established that the substitution-inert complex Cr iL-ATP binds at the ATP binding site of the pyruvate kinase-M + complex, and studies with this magnetic probe have led to the construction of molecular models for composite complexes of this important enzyme. Steady-state kinetic studies on the Mn +-, Ni +-, and Co +-activated systems suggest that the substrates of pyruvate kinase are PEP, uncomplexed ADP, and free bivalent cations. Magnesium-complexed ADP and ATP bind at the same site on yeast phosphoglycerate kinase, as do the uncomplexed nucleotides. 

Cibacron blue F3G-A displays affinity for a wide range of nucleotide-binding enzymes. This has been exploited in the resolution of two kinases ftom a crude yeast extract. The HPAC column, 6-aminohexyl-Cibacron blue F3G-A-silica (see Section 4.2.1), is loaded with a crude yeast extract which contains the two enzymes hexokinase and 3-phosphoglycerate kinase and which are both adsorbed on the column. Unretarded proteins are washed off and subsequently the two enzymes are eluted separately, the first in the presence of 10 mM Mg. ATP and 25 mM D-glucose or D-mannose and the second in the presence of 10 mM Mg.ATP and 3-phosphoglycerate Figure 3). 

The Rossmann fold is also a conservative structure. Such a structure, which consists of parallel strands of p sheets flanked by two helices on each side which are antiparallel with regard to the sheets, is found in NAD dehydrogenases, in several kinases (e.g., adenylate kinase, phosphoglycerate kinase), and in all enzymes which have a coenzyme with a nucleotide part, NAD+ or ATP. 

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