Cadmium-binding components in soybean plants.

Soybean (Glycine max L.) plants exposed to (109)Cd readily absorb the element. Differential centrifugation of leaf, stem, and root homogenates followed by radioassay showed that Cd was associated primarily with the 105,000g supernatant. Separation of this fraction by gel chromatography and subsequent analysis by radioassays revealed that (109)Cd was bound to macromolecules of >50,000, 13,800, and 2,280 molecular weights. The >50,000 and 2,280 molecular weight fractions probably are nonspecific binding of Cd to normal cell components. The 13,800 molecular weight (109)Cd-bound component was found to be inducible by cadmium. It had a high ultraviolet absorbance at 254 nm and a low absorbance at 280 nm at pH 8.6.