ABSTRACT
Heavy metals in solution are highly reactive and readily combine with many biological molecules, including constituents of cell membranes such as proteins and phospholipids. Reaction with proteins is determined by
Electric charge: a cationic metal is attracted to proteins by their usual electronegativity (Perkins, 1981), with metals binding to carboxy and other anionic groups.
Presence of chelating structures such as SH groups, imidazole residues, etc.
The tertiary structure of proteins, as illustrated by the specific complex formation of Cd with the cysteine clusters in metallothionein (see, e.g., Elinder and Nordberg, 1985).
