title: Inhibition of horse muscle acylphosphatase by pyridoxal 5'-phosphate.
abstract: It has been shown that horse muscle acylphosphatase is inhibited by pyridoxal 5'-phosphate and that the inhibition is pH dependent, reversible and competitive with respect to substrate binding. Spectral analysis on the EI complex demonstrates the presence of a Schiff base. Reduction of the pyridoxal 5'-phosphate-inhibited enzyme with sodium borohydride, followed by amino acid analysis, produces a diminution of the free lysine peak and the appearance of a new peak corresponding to epsilon-pyridoxyllysine. The results suggest that there is at least one NH2-lysyl residue of horse muscle acylphosphatase at or near the active site of the enzyme.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001665:Binding Sites; D006736:Horses; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008239:Lysine / Q000494:pharmacology; D009132:Muscles / Q000187:drug effects / Q000201:enzymology*; D009994:Osmolar Concentration; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors*; D011485:Protein Binding; D011732:Pyridoxal Phosphate / Q000494:pharmacology*; D012545:Schiff Bases; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet; D013997:Time Factors
chemical_list: D000596:Amino Acids; D012545:Schiff Bases; D011732:Pyridoxal Phosphate; D010744:Phosphoric Monoester Hydrolases; D008239:Lysine