title: Spatial proximity of a tyrosyl and a lysyl residue in the active site region of yeast 3-phosphoglycerate kinase.
abstract: The effect of 7-chloro-4-nitrobenzofurazan on yeast 3-phosphoglycerate kinase causes a modification of one tyrosyl residue concomitantly with a total loss of activity of the enzyme. The modification is not accompanied by any significant conformational change. A total protection against inactivation is observed with the substrates : furthermore, AMP, tripolyphosphate and pyrophosphate afford an effective protection. At pH 9, a shift in the absorbance spectrum of the tyrosine O-nitrobenzofurazan derivative of 3-phosphoglycerate kinase is observed. It can be related to the transfer of the reagent from tyrosine to lysine. The N-nitrobenzofurazan derivative is also completely inactive. It is concluded that a lysine residue is located close to the essential tyrosyl residue.
mesh_terms: D009327:4-Chloro-7-nitrobenzofurazan / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites / Q000187:drug effects; D007700:Kinetics; D008239:Lysine / Q000032:analysis*; D009578:Nitrobenzenes / Q000494:pharmacology; D010735:Phosphoglycerate Kinase / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D014443:Tyrosine / Q000032:analysis*
chemical_list: D009578:Nitrobenzenes; D014443:Tyrosine; D010735:Phosphoglycerate Kinase; D009327:4-Chloro-7-nitrobenzofurazan; D008239:Lysine