[Parameters influencing inactivation-dissociation/reactivation-association phenomena induced by variations of ionic strength of L (+)lactate: cytochrome c oxidoreductase (cytochrome b2) extract of the yeast Hansenula anomala].
H-flavocytochrome b2, a tetramer enzyme, is inactivated, at low ionic strength and can be reactivated, increasing the ionic strength of the medium. The inactivation-reactivation process was structurally manifested by a dissociation-association phenomenon between subunits. It was clearly shown that the inactivation-dissociation process appeared independent of enzyme concentration whereas the reactivation-association phenomenon was enzyme concentration dependent. However, proteins protect H-flavocytochrome b2 from inactivation-dissociation, only when electrostatic interactions are possible between the two proteins: Horse heart cytochrome c was a good protector whereas serum albumin had no protector effect.
D000818:Animals; D001203:Ascomycota / Q000201:enzymology*; D003574:Cytochrome c Group / Q000378:metabolism; D004789:Enzyme Activation; D006736:Horses; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D042844:L-Lactate Dehydrogenase (Cytochrome); D046911:Macromolecular Substances; D009206:Myocardium / Q000378:metabolism; D009994:Osmolar Concentration; D010843:Pichia / Q000201:enzymology*
D003574:Cytochrome c Group; D046911:Macromolecular Substances; D007770:L-Lactate Dehydrogenase; D042844:L-Lactate Dehydrogenase (Cytochrome)
Paramètres influençant les phénomènes d'inactivation-dissociation/réactivation-association induits par des variations de force ionique chez la L (+)lactate: cytochrome c oxydoréductase (cytochrome b2) extraite de la levure Hansenula anomala.