Structural changes of proteins in fish red blood cells after copper and mercury treatment.

Abstract

Exposure of fish red blood cells to increased concentrations (0.05–0.3 mmol/L) of copper and mercury ions may initiate structural changes in cells as detected by spin labeling method. Both heavy metals decreased membrane fluidity as indicated by methyl 5-doxylpalmitate and methyl 12-doxylstearate spectra. Furthermore, copper and mercury have been found to induce conformational alterations of internal peptides and proteins as determined by using 4-maleimido-2,2,6,6-tetramethylpiperidine-1-oxyl. Both heavy metal ions changed the internal viscosity of red blood cells. These results suggest that the possible cause of the damage of cells may be metal-protein interactions in the cells, but may exclude the oxidative mechanism of such damage.