Chapters 3 to 5 give an account of bacterial MTs, MTs in yeast and fungi, and MTs in plants. Most astonishingly, the MTs of bacteria and plants contain next to cysteine also histidine residues and thus, metal ions are not only sulfur- but also imidazole-coordinated which gives rise to zinc finger-like structures. Remarkably, yeast and fungal MTs are Cu(I) rather than Zn(II) or Cd(II) binding proteins. Next, Chapters 6 through 9 discuss the MTs of dipteran insects, including the model organism Drosophila melanogaster, earthworms and nematodes, as well as echinoderms, crustaceans, molluscs, and fish. Actually, aquatic animals, both vertebrates and invertebrates, have the potential to be used for monitoring metal contamination in aquatic ecosystems. Interestingly, in Chapter 9 the remarkable speculation is presented that under chronic natural exposure conditions the animals establish a trade-off between the qcostq of detoxifying non-essential metals and the qcostq of allowing some of these metals to spill over onto metal-sensitive sites. This contrasts with laboratory experiments involving aquatic animals, where the toxicity of non-essential metals normally exhibits a threshold response: at low exposure concentrations the organisms can detoxify the incoming metal and thus, tolerate the exposure, whereas at concentrations above the threshold, the detoxification mechanism is no longer able to protect the organism completely.Trx, covalently linked to the protein of interest, avoids inclusion body formation and thereby increases the levels of soluble ... The high reactivity of iron with different oxygen species demands tightly controlled regulatory circuits during the anbsp;...
|Title||:||Metallothioneins and Related Chelators|
|Author||:||Astrid Sigel, Helmut Sigel, Roland K. O. Sigel|
|Publisher||:||Royal Society of Chemistry - 2009-01-01|