title: Determination of the interaction of lactate dehydrogenase with high-molecular-weight derivatives of AMP by affinity electrophoresis.
abstract: The interaction of lactate dehydrogenase with high-molecular-weight derivatives of AMP was studied by affinity electrophoresis in an alkaline buffer system and by means of kinetic measurements. AMP was coupled to synthetic hydroxypropylmethacrylamide copolymers through glycine, 6-aminohexanoic and 12-aminododecanoic spacer arms. The values of the dissociation constants (K) of the lactate dehydrogenase isoenzymes--immobilized AMP complexes determined by affinity electrophoresis decreased with increasing length of the spacer arm. Lactate dehydrogenase was competitively inhibited by high-molecular-weight derivatives of AMP; values of the inhibition constants (Ki) also depended on the spacer arm: the longer the spacer arm the stronger was the interaction between the enzyme and the inhibitor. Ki values for high-molecular weight derivatives of AMP were lower than those obtained for free AMP.
mesh_terms: D000249:Adenosine Monophosphate / Q000031:analogs & derivatives* / Q000378:metabolism; D000818:Animals; D004285:Dogs; D004586:Electrophoresis / Q000379:methods; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism
chemical_list: D000249:Adenosine Monophosphate; D007770:L-Lactate Dehydrogenase