title: Synthesis and differential properties of creatine analogues as inhibitors for human creatine kinase isoenzymes.
abstract: Fourteen new creatine analogues, all with a guanidine function and either a polar or an apolar group instead of the creatine carboxylic function, were tested as potential inhibitors for human creatine kinase by kinetic analysis of their effects on the reaction rate. Only compounds bearing an apolar aromatic moiety, which was spaced from the guanidine function by at least two bonds, proved to have a significant inhibitory activity and showed a mixed-type inhibition similar to that of creatine. Among these compounds 2,6-dichlorobenzylguanidine (Ki = 5.6 mM and 39.8 mM for muscle-type and brain-type creatine kinases, respectively) and 3-(2,6-dichlorophenyl)propylguanidine (Ki = 15 mM and 4.5 mM) were the more potent inhibitors and showed a significant isoenzyme selectivity between muscle- and brain-type creatine kinases. Our results are in agreement with recent data that suggest the location of a hydrophobic pocket near the guanidine-binding domain of the enzyme. The observed selectivity in isoenzyme inhibition may be useful to study structural differences in catalytic centers.
authors.affiliation: Laboratoire de Biochmie C, Hopital Edouard Herriot, Lyon, France.
authors.forename: K L
authors.initials: KL
authors.lastname: Min
authors.forename: J P
authors.initials: JP
authors.lastname: Steghens
authors.forename: R
authors.initials: R
authors.lastname: Henry
authors.forename: A
authors.initials: A
authors.lastname: Doutheau
authors.forename: C
authors.initials: C
authors.lastname: Collombel
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D003401:Creatine / Q000031:analogs & derivatives* / Q000494:pharmacology; D003402:Creatine Kinase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000138:chemical synthesis* / Q000378:metabolism / Q000494:pharmacology; D006146:Guanidines / Q000494:pharmacology; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D016415:Sequence Alignment
chemical_list: D004791:Enzyme Inhibitors; D006146:Guanidines; D007527:Isoenzymes; D003402:Creatine Kinase; D003401:Creatine