Premium
Interactions of Insulin‐Mimetic Vanadium Complexes with the Cell Constituents ATP and Glutathione
Author(s) -
Dörnyei Ágnes,
Marcão Susana,
Costa Pessoa João,
Jakusch Tamás,
Kiss Tamás
Publication year - 2006
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.200600385
Subject(s) - chemistry , vanadium , glutathione , aqueous solution , ternary operation , metal , adenosine triphosphate , ionic bonding , chelation , ternary complex , inorganic chemistry , electron paramagnetic resonance , ionic strength , metal ions in aqueous solution , ion , enzyme , biochemistry , organic chemistry , physics , nuclear magnetic resonance , computer science , programming language
In order to assess the molecular form of vanadium insulin‐mimetic complexes in cells, the interactions of V IV O–maltolate and V IV O–dipicolinate systems with adenosine 5′‐triphosphate (ATP) and glutathione (GSH) in aqueous solution were studied by employing pH potentiometry, and EPR, CD and UV/Vis spectroscopy. The stoichiometries and stability constants of the complexes formed were determined at 25 °C with an ionic strength of I = 0.2 mol dm –3 (KCl). The most probable binding mode of the complexes formed in solution was determined by means of various spectral methods. The results suggest that from among the important cell constituents, GSH mostly takes part in the reduction of V V to V IV and helps keep V IV in this oxidation state. ATP, which is a strong V IV O binder, chelates the metal ion, forming binary and/or ternary complexes. The results of this work strongly suggest that ATP binds relevant V IV O species under cellular conditions and thus might somehow be involved in the insulin‐mimetic action of V IV O compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)