Cadmium binding

Rauser, W.E. (1984). Isolation and partial purification of cadmium-binding protein from roots of the grass Agrostis gigantea. Plant Physiology, 74, 1025-9. 

Reese, R.N. Wagner, G.J. (1987). Properties of tobacco Nicotiana tabacum) cadmium-binding peptide(s). Biochemistry Journal, 241, 641-7. 

Avdeef, A. Zelazowski, A. J. Garvey, J. S., Cadmium binding by biological ligands. 3. Five- and seven-cadmium binding in metallothionein A detailed thermodynamic study, Inorg. Chem. 24, 1928-1933 (1985). 

Playle, R.C., D.G. Dixon, and K. Bumison. 1993a. Copper and cadmium binding to fish gills modification by dissolved organic carbon and synthetic ligands. Canad. Jour. Fish. Aquat. Sci. 50 2667-2677. 

Playle, R. C., Dixon, D. G. and Burnison, K. (1993). Copper and cadmium binding to fish gills estimates of metal-gill stability constants and modelling of metal accumulation, Can. J. Fish. Aquat. Sci., 50, 2678-2687. 

Conditional stability constants have been determined for cadmium binding to humic acid in freshwater, log Kk 6.5 [27], which may be comparable to binding to humic acid coated particles. The experiments demonstrated the importance of cadmium uptake from particles rather than from the dissolved phase. The authors recognised that the overall conclusion was similar to previous studies [28], but there remain inconsistencies in the uptake levels which may be related to the heterogeneity of the systems. Uptake from the intestine into the mucosal cells was not investigated. It was presumed that the material was digested extracellularly by hydrolytic enzymes and the released metal was taken up by facilitated diffusion. 

Ke, H.-Y. D. and Rayson, G. D. (1992). Characterization of cadmium binding sites on Datura innoxia using cadmium-113 NMR spectrometry, Environ. Sci. Technol., 26, 1202-1205. 

Metallothionein was first discovered in 1957 as a cadmium-binding cysteine-rich protein (481). Since then the metallothionein proteins (MTs) have become a superfamily characterized as low molecular weight (6-7 kDa) and cysteine rich (20 residues) polypeptides. Mammalian MTs can be divided into three subgroups, MT-I, MT-II, and MT-III (482, 483, 491). The biological functions of MTs include the sequestration and dispersal of metal ions, primarily in zinc and copper homeostasis, and regulation of the biosynthesis and activity of zinc metalloproteins. 

The binding of transcription factors to nucleotide sequences, which facilitates gene transcription, can be influenced by chemicals. For example, cadmium binds to a metal-binding protein factor, MFF-1, in place of zinc and so induces metallothionein synthesis. This, as it happens is a detoxication, as metallothionein binds cadmium. 

This may be due to the interference with the mitochondrial electron transport chain. Thus, cadmium binds to complex III at the Q0 site between semi-ubiquinone and heme b566. This stops delivery of electrons to the heme and allows accumulation of semi-ubiquinone, which in turn transfers the electrons to oxygen and produces superoxide. 

Figure 10.1. (a) Rhamnolipid from P. aeruginosa ATCC 9027 showing cadmium binding, (b) Structure of the iron-siderophore complex of enterobactin. 

Bartoff, M., Brennan, E. Price, C.A. (1980). Partial characterization of a cadmium-binding protein from the roots of cadmium-treated tomato. Plant Physiology 66, 438-41. 

Casterline, J.L., Jr Barnett, N.M. (1982). Cadmium-binding components in soybean plants. Plant Physiology 69, 1004-7. 

Murasugi, A., Wada, C. Hayashi, Y. (1981). Cadmium-binding peptide induced in fission yeast, Schizosaccharomyces pombe. Journal of Biochemistry (Tokyo) 90, 1561-4. 

Rauser, W.E. Glover, J. (1984). Cadmium-binding proteins in roots of maize. Canadian Journal of Botany 62, 1645-50. 

Vogeli-Lange, R. Wagner, G.J. (1990). Subcellular localization of cadmium and cadmium-binding peptides in tobacco leaves. Plant Physiology 92, 1086-93. 

Wagner, G.J. Trotter, M. (1982). Inducible cadmium-binding complexes of cabbage and tobacco. Plant Physiology 69, 804-9. 

Kaschl, A., Romheld, V., and Chen, Y. (2002). Cadmium binding by fractions of dissolved organic matter and humic substances from municipal solid waste compost. /. Environ. Qual. 31,1885-1892. 

M. P. Waalkes, P. L. Goering, Metallothionein and other cadmium-binding proteins recent developments, Chem. Res. Toxicol., 3 (1990), 281-288. 

Metallothioneins (MTs) are a superfamily of low-molecular-weight (<7000-dalton) intracellular metal-binding proteins, which, in many species, play a critical role in (a) the detoxification of nonessential metals such as Cd2+ and Hg2+ and (b) the regulation of intracellular concentrations of essential metals such as Zn2+ and Cu+. In 1957, Kagi and Vallee first purified and characterized MT as a cadmium-binding protein in equine kidney. 

Fokkink, L.G.J., Surface Charge Formation and Cadmium Binding on Rutile and Hematite, Ph.D. thesis, Agricultural University, Wageningen, The Netherlands, 1987. 

Squibb KS, Pritchard JB, Fowler BA. Cadmium metallothionein nephrotoxicity ultrastructural/biochemical alterations and intracellular cadmium-binding. J Pharmacol Exp Ther 1984 229 311-321. 

Nordberg GF, Jin T, Nordberg M. Subcellular targets of cadmium nephrotoxicity cadmium binding to renal membrane proteins in animals with or without protective metallothionein synthesis. Environ Elealth Perspect 1994 102 (suppi 3) 191-194. 

Cadmium is a classic cumulative poison that accumulates in the kidneys over a lifetime. It is transported in the blood by erythrocytes and by albumin, and it is stored mainly in the liver and kidneys as metallothionein (50-75% of the body burden). Cadmium binds to many proteins at the sulfate and carbonyl sites. The half-life of cadmium in these two organs may be as long as 30 years. The correlation between years of exposure and blood levels does not appear to be significant. Cadmium also accumulates in the bones and the placenta of pregnant women. 

Slice, L.W., Freedman, J.H. and Rubin, C. (1990) Purification, characterization, and cDNA cloning of a novel metallothionein-like, cadmium-binding protein from Caenorhabditis elegans. Journal of Biological Chemistry, 265, 256-263. 

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