Sodium decavanadate

Sodium and potassium vanadates. The authors [68] investigated mechanochemical synthesis of sodium and potassium decavanadates starting from V Oj and conesponding carbonates or metavanadates. They have shown that varying the initial ratio of components and the time of mechanical activation of the mixtures, the synthesis of different vanadates, including decavanadates, occurs, characterized by high rate of reactions. 

Vanadate-induced photo-oxidation of serine and subsequent cleavage of the protein were also observed for ribulose-l,5-diphoshate carboxylase/oxygenase from spinach leaves. Activity could be restored by treatment with sodium boronate, which reduces formylglycine back to serine.Similarly, vanadate-induced UV oxidation of threonine (Thr353, at the phosphorylation site) in the sarcoplasmatic reticulum (SR) Ca +-ATPase can be restored by reduction with Na[BH4]. For monovanadate to become catalyti-cally active it is essential that Mg + and ADP bind to the phosphorylation site of the enzyme in its Ca +-receptive conformation, suggesting the formation of an active MgADPV as proposed for the myosin fragmentation. In contrast, decavanadate catalyses the photo-oxidation of a serine (Seri 86) residue in the SR ATPase in the absence of ADP.P bl... 

Savan. [Kerr-McGee] Sodium ammonium decavanadate. 

During the titration of sodium or ammonium vanadate at a high ionic strength, no solid phase is formed around H /V = 3 corresponding to the existence of the zero-charge species. The decavanadate is in equilibrium with the non-condensed cation [V02(OH2)4] and the kinetic phenomena are such that there is a direct transition from one form to the other [2,50]. 

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