The interaction of a recently developed intracellular superoxide dismutase analogue, Fe(II)-N,N,N',N'-tetrakis(2- pyridylmethyl)ethylenediamine (Fe(II)-TPEN), with reactive oxygen species was investigated under in vitro conditions. The complex catalyzed the dismutation of enzyme- or radiolysis-generated superoxide with the production of H2O2; under steady-state conditions the equilibrium was strongly shifted toward Fe(III)-TPEN. Fe(II)-TPEN reacted with H2O2 to generate hydroxyl radicals in a Fenton reaction. The oxidized Fe(III)-TPEN was readily reduced by ascorbate or glutathione. Given the capacity to produce hydroxyl radicals and the reaction with cellular reductants it seems unlikely that Fe-TPEN may find widespread use as an intracellular superoxide dismutase substitute.
Iuliano, L., Pedersen, J., Ghiselli, A., Praticò, D., Rotilio, G., Violi, F. (1992). Mechanism of reaction of a suggested superoxide-dismutase mimic, Fe(II)-N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine. ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS, 293(1), 153-7.
Mechanism of reaction of a suggested superoxide-dismutase mimic, Fe(II)-N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine
Pedersen JZ;Rotilio G;
1992-02-14
Abstract
The interaction of a recently developed intracellular superoxide dismutase analogue, Fe(II)-N,N,N',N'-tetrakis(2- pyridylmethyl)ethylenediamine (Fe(II)-TPEN), with reactive oxygen species was investigated under in vitro conditions. The complex catalyzed the dismutation of enzyme- or radiolysis-generated superoxide with the production of H2O2; under steady-state conditions the equilibrium was strongly shifted toward Fe(III)-TPEN. Fe(II)-TPEN reacted with H2O2 to generate hydroxyl radicals in a Fenton reaction. The oxidized Fe(III)-TPEN was readily reduced by ascorbate or glutathione. Given the capacity to produce hydroxyl radicals and the reaction with cellular reductants it seems unlikely that Fe-TPEN may find widespread use as an intracellular superoxide dismutase substitute.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
