beta-(2-furyl)acryloyl-phosphate and arsenic-acid

The effect of ATP on the formation, spectral properties, and reactions of [beta-(2-furyl)acryloyl]glyceraldehyde-3-phosphate dehydrogenase (FA-GPDH) has been investigated. The chromophoric FA-GPDH has the advantage of providing spectrophotometric signals of the interaction of acyl enzyme with nucleotides and dinucleotides. The results are consistent with the exclusive existence of two acyl-enzyme conformations previously inferred from the interaction of the acyl enzyme with NAD+ and NADH. ATP interaction stabilizes a conformation different from that stabilized by NAD+. The inhibitory effects of ATP on these reactions are consistent with the reported inhibitory effect of ATP on the steady-state reaction with the true substrate. The physiological significance of these results to the regulation of glycolysis, via the ligand-dependent fate of 3-phosphoglycerol-GPDH, is discussed.

Topics: Acrylates; Acylation; Adenosine Triphosphate; Animals; Arsenates; Glyceraldehyde-3-Phosphate Dehydrogenases; In Vitro Techniques; Kinetics; NAD; Protein Conformation; Spectrophotometry, Ultraviolet