Metal-citrate complexation

Joshi-Tope G, AJ Francis (1995) Mechanisms of biodegradation of metal-citrate complexes by Pseudomonas fluorescens. J Bacterial 177 1989-1993. 

Uptake of small organic metal complexes over transport systems of organic metabolites may be possible, for example, of small organic acids like citrate or amino acids. However, only few examples of such processes have been studied so far. Increased uptake of cadmium by an alga has been observed in the presence of citrate and has been attributed to accidental transport of the metal-citrate complex over a citrate transporter [212]. Transport systems of inorganic anions may also play a role in metal transport. Silver uptake by algae was enhanced in the presence of thiosulfate. In this case, the silver thiosulfate complex was transported over a sulfate uptake system [213]. It remains to be demonstrated how widespread these processes may be for metal uptake in the aquatic environment [12]. 

Brookhaven National Laboratory s (BNL s) biochemical recovery of radionuclides and heavy metals is a patented biochemical recovery process for the removal of metals and radionuclides from contaminated minerals, soil, and waste sites. In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals and radionuclides from solid wastes by the formation of water-soluble, metal-citrate complexes. The complex-rich extract is then subjected to microbiological biodegradation that removes most of the extracted heavy metals. 

The possible combinations and stoichiometries of AP" " or Fc +, cit -, H+, and OH that may occur in a metal-citrate species are numerous. In general, the formation of soluble metal—citrate complexes can be described by... 

Jordan, S.L., I.R. McDonald, A.J. Kraczkiewicz-Dowjat, D.P. Kelly, F.A. Rainey, J-.C. Murrell, and A.P. Wood. 1997. Autotrophic growth on carbon disulfide is a property of novel strains of Paracoccus denitrificans. Arch. Microbiol. 168 225-236. Joshi-Tope, G. and A.J. Francis. 1995. Mechanisms of biodegradation of metal-citrate complexes by Pseudomonas fluorescens. J. Bacteriol. 177 1989-1993. 

A.J. Francis, C.J. Dodge, J.B. Gillow, Biodegradation of metal citrate complexes and implications for toxic metal mobility, Nature 356 (1992) 140-142. 

Pyatnitskii IV, Kharchenko RS (1964) Extraction of metal citrate complexes in the presence of tributylamine. Ukrain Khim Zum 30 311-313... 

Lensbouer, J.J. and Doyle, R.R (2010) Secondary transport of metal-citrate complexes the CitMHS family. Crit Rev Biochem Mol Biol 45, 453 62. 

Wagner and co-workers generated single-crystalline orthorhombic NaTaOs nanorods [162], Highly anisotropic pseudo-cubic KNbOs nanocrystallites with morphologies of nanoneedles and nanoplatelets can be obtained after the crystallization of the precursor gel derived from a polymerized complex process, which is based on the Pechini-type reaction route that starts from a precursor solution of the respective metal-citrate complexes [163],... 

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