From BioMineWiki

Jump to: navigation, search

Proteins, polysaccharides and nucleic acids are the three major polymer groups ubiquitous in the living world and found in all members of the animal, plant, protozoan and microorganism groups.

Biopolymers may bind to soluble metal species

Biopolymers, constituents of the microbial cells, may have a significant potential of binding soluble metal species through their functional groups.


As a generalization, the binding of metal ions to biopolymers is likely to occur via two major mechanisms:

  1. Simple ion-exchange.
  2. Through the formation of complexes (co-ordination compounds) which may be chelates.

Because of the complexity of most biopolymers, it is very likely that more than one process of binding takes place in a system at the same time. Two simplified examples are:

  1. Metal-ion exchange: via cation-binding by ionisable groups found in biopolymers such as carboxyl, organic phosphate and organic sulphate.
  2. Complex formation by organic molecules with metal atoms: ligand centres in the organic species i.e. the presence of atoms having lone electron pairs to donate. In the biopolymers these are most likely to be neutral trivalent nitrogen atoms and neutral divalent oxygen or sulphur atoms.
Personal tools