The methylene analogue of 3-phospho-d-glycerate, 2-hydroxy-4-phosphono-dl-butyric acid, is a substrate for phosphoglycerate kinase. The pK(a) values for the final dissociation of the natural substrate and its methylene isostere are 6.20 and 7.45 respectively. The kinetic parameters K(m) and k(cat.) for the enzyme-catalysed reaction were determined at pH6.9 and 8.5 by using low substrate concentrations. Although the k(cat.) values for the two substrates at each pH are similar, there is a 60-fold increase in the K(m) value for the methylene isostere on going to the lower pH. The results are most readily interpreted in terms of a dianionic group on C-3 being required for efficient substrate binding to the enzyme.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1168177 | PMC |
http://dx.doi.org/10.1042/bj1410721 | DOI Listing |
ACS Chem Biol
September 2019
Junior Research Group Synthetic Microbiology , Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Beutenbergstr. 11a , 07745 Jena , Germany.
Coenzyme F is a specialized redox cofactor with a negative redox potential. It supports biochemical processes like methanogenesis, degradation of xenobiotics, and the biosynthesis of antibiotics. Although well-studied in methanogenic archaea and actinobacteria, not much is known about F in Gram-negative bacteria.
View Article and Find Full Text PDFArch Biochem Biophys
June 1994
Department of Biochemistry, University of Tennessee, Knoxville 37996-0840.
An exchange-inert Rh(H2O)4ATP complex showed a one-turnover substrate activity with yeast phosphoglycerate kinase. Transfer of the phosphoryl group between ATP and 3-phosphoglycerate occurs with both substrates in the coordination sphere of the metal ion. Because of the slow ligand exchange rates of Rh3+, the reaction product 1,3-diphosphoglycerate (1,3-dPGA) remained coordinated to the metal ion.
View Article and Find Full Text PDFJ Biol Chem
February 1993
Department of Biochemistry, University of Tennessee, Knoxville 37996-0840.
beta, gamma-Bidentate CrATP, a stable exchange-inert metal-nucleotide analog, was used as a probe of the conformation of the substrates at the active site of yeast phosphoglycerate kinase (PGK). The paramagnetic effects of Cr3+ on the longitudinal relaxation rates (1/T1p) of the 1H, 31P, and 13C nuclei of 3-phospho-D-glycerate (3PGA) were examined to determine the distances between enzyme-bound CrATP and the nuclei of 3PGA in the ternary PGK.CrATP.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
April 1991
Department of Botany and the Center for Aquatic Plants, University of Florida, Gainesville, FL 32611, USA.
Udotea flabellum is a marine, macroscopic green alga with C4-like photosynthetic characteristics, including little O2 inhibition of photosynthesis, a low CO2 compensation point, and minimal photorespiration; but it lacks anatomical features analogous to the Kranz compartmentation of C4 plants, and phosphoenolpyruvate carboxylase [PEPC; orthophosphate:oxaloacetate carboxy-lyase (phosphorylating), EC 4.1.1.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!