Binuclear Electron-Paramagnetic-Resonance Signals of Arthropodan Methaemocyanins in the Presence of Nitrite
The deoxy- and oxyderivatives of haemocyanin are diamagnetic; in the oxyderivative the copper(II) ions in the binuclear copper site are strongly magnetically coupled. A strong interaction between the two copper(II) ions in a copper pair is favoured when only very few atoms form a superexchange pathway leading to a coupling of the unpaired spins. The copper(II) ions can also be magnetically coupled as a function of their distance and thus give rise in electron paramagnetic resonance (EPR) to a broad triplet signal near g = 2 and a weakly allowed signal at half field near g = 4, as observed for Helix pomatia methaemocyanin with acetate at pH 5.7 (1, 2).
KeywordsPeroxide Microwave Superoxide Nitrite Tate
Unable to display preview. Download preview PDF.
- 1.Witters, R., De Ley, M., and Lontie, R., in Structure and Functionof Haemocyanin (Bannister, J.V., ed.), pp. 239–244, Springer Verlag, Berlin (1977).Google Scholar
- 2.Deleersnijder, W., Witters, R., and Lontie, R., Life Chem. Reports, Suppl. 1, 289–290 (1983).Google Scholar
- 4.Witters, R., Van Hoof, D., Deleersnijder, W., Tahon, J.-P., and Lontie, R., this volume, pp. 445–448 (1986).Google Scholar