Metal-induced dimerization of Cd7-metallothionein. Role of anions.
Inorganic phosphate participates in the nonoxidative Cd-dependent dimerization of Cd7-metallothionein (Cd7-MT) and is bound to the MT dimers. In order to obtain insight into the specificity of phosphate-MT interaction, an investigation has been made on the effect of a series of oxyanions and organic phosphates on Cd-induced dimerization of Cd7-MT. It has been demonstrated that from the oxyanions studied, only arsenate and tungstate can promote Cd-induced dimerization of Cd7-MT. Effect of arsenate is quantitatively similar to that of phosphate and appears at submillimolar concentrations, whereas tungstate promotes dimerization of MT at higher, millimolar concentrations. A number of other oxyanions, ie, molybdate, vanadate, and selenate as well as organic phosphates (phenyl phosphate, serine O-phosphate, D-ribose 5-phosphate, L-glycerol 3-phosphate, D-fructose 6-phosphate, D-glucose 6-phosphate, adenosine monophosphate (AMP), cyclic adenosine monophosphate (cAMP), nicotinamideadenine-dinucleotide (NADP), pyridoxal 5-phosphate) had no influence on Cd-induced dimerization of MT. Results obtained strongly indicate a highly specific role of inorganic phosphate in Cd-induced dimerization of Cd7-MT.
Palumaa
P
P
Institute of Molecular and Cell Biology, University of Tartu, Estonia.
Vaher
M
M
D000818:Animals; D000838:Anions / Q000494:pharmacology; D001149:Arsenates / Q000494:pharmacology; D001704:Biopolymers; D002104:Cadmium / Q000494:pharmacology*; D002850:Chromatography, Gel; D007700:Kinetics; D008099:Liver / Q000737:chemistry; D008668:Metallothionein / Q000737:chemistry* / Q000378:metabolism; D010755:Organophosphates / Q000378:metabolism / Q000494:pharmacology; D010710:Phosphates / Q000494:pharmacology; D011487:Protein Conformation; D011817:Rabbits; D017973:Tungsten Compounds / Q000494:pharmacology
D000838:Anions; D001149:Arsenates; D001704:Biopolymers; D010755:Organophosphates; D010710:Phosphates; D017973:Tungsten Compounds; C004203:cadmium-binding protein; D002104:Cadmium; D008668:Metallothionein; C025657:arsenic acid; C018279:sodium phosphate; C045951:tungstate