Detection of cadmium-binding proteins in fish chronically exposed to heavy metals

Abstract

Studies were undertaken to determine the presence of cadmium-binding proteins in fish from a metal-contaminated flyash disposal pond and relatively uncontaminated hatchery ponds. Fractionation of gill cytosolic proteins by gel filtration indicated three classes of cadmium-binding proteins. While no cadmium was detected in the metallothionein (MT)-like fraction of the hatchery fish, 1% of the cytosolic cadmium was detected in this fraction for ash pond fish. Cadmium concentrations in the flyash pond were previously reported as ranging from 0.30 to 0.98 μg/L. This level of exposure may be insufficient to induce significant biosynthesis of MT-like proteins.