What does Dipicolinic acid chelate?

Answer 1

Dipicolinic acid (Pyridine-2,6-dicarboxylic acid, DPA) is known to chelate a wide variety of multivalent metal ions, including Ca(II), Mg(II), Cu(II), Ni(II), Zn(II), Co(II), Tb(III), U(IV), and Mn(II) ions. I will elaborate on some of the biochemical aspects of DPA. DPA is structurally related to other pyridine carboxylic acids like nicotinic acid (vitamin B3). These related compounds are found in the metabolic pathways of animals and are utilized for the transport and scavenging of metal ions by the body. Approximately 15% (w/w) of the material composing Bacillus spores is DPA; a very large concentration for a cell to express. One might ask, 'Why should so much energy be utilized in the production of extraordinary concentrations of DPA?'. It has been determined with certainty that large DPA-Ca(II) complexes are responsible for the high thermal and UV stability of Bacillus spores. Particularly, the role in defense against damage to nucleic acids (DNA) has been reported [Journal of Bacteriology, June 2006, p. 3740-3747, Vol. 188, No. 11]. Thus, survival of the spores is dependent on the production of vast quanities of DPA, reenforcing the optimization of DPA signalling pathways for these species.