Book ChapterDOI
Metal Ions: Metabolic and Toxic Effects
K. Simkiss,A.Z. Mason +1 more
- pp 101-164
TLDR
This chapter provides a general understanding of metal ion involvement in the various physiological compartments of the mollusk.Abstract:
Publisher Summary This chapter provides a general understanding of metal ion involvement in the various physiological compartments of the mollusk. Five elements—potassium, sodium, magnesium, calcium, and chlorine—are involved in establishing the ionic composition of the intracellular and extracellular fluids. These elements are also manipulated by cells so as to produce the osmotic equilibria that are necessary for living systems. There is a large group of elements that are required in only trace amounts for a whole variety of metabolic activities. Many of these elements are metals and they perform a wide variety of functions of which the activity of metalloenzymes, the transport of oxygen, and redox activities are the best understood. A large number of metalloenzymes and metal ion-activated enzymes are now known. Some metals, such as zinc and magnesium, are frequently associated with enzymes, although they may not be structurally a part of the molecule. A second major group of metal-dependent functions involves the respiratory pigments.read more
Citations
More filters
Journal ArticleDOI
Mechanisms of heavy metal cation homeostasis in marine invertebrates
Aldo Viarengo,J. A. Nott +1 more
TL;DR: The biochemical characteristics of metallothioneins and the relationship between their amino acid composition and heavy metal binding capacity are elucidated, and data are reported concerning the sequestration of heavy metal cations in insoluble granules as a mechanism of metal detoxification.
Journal ArticleDOI
Cellular and subcellular distribution of metals in molluscs.
TL;DR: The assessment of metal levels in target cells of sentinel molluscs by microscopic techniques provides an early‐warning measure, with promising applications as an exposure biomarker for environmental monitoring programs.
Journal ArticleDOI
Contaminated food and uptake of heavy metals by fish: a review and a proposal for further research.
TL;DR: It is concluded that future investigations on transference of heavy metals to fish must take into more careful consideration the specific ecological situation of a given environment.
Journal ArticleDOI
Models of regulation and accumulation of trace metals in marine invertebrates
TL;DR: Key determinants of trace metal body concentrations are bioavailability from seawater and from food, but the nature of the trace metal and the physiological state of the organism, strongly influence subsequent handling, distribution, tissue accumulation and excretion.
Journal ArticleDOI
Patterns of accumulation, distribution and liberation of zn, cu, cd and pb in different organs of the land snail Helix pomatia L
Reinhard Dallinger,W. Wieser +1 more
TL;DR: The snail Helix pomatia was fed lettuce enriched with zinc, cadmium, lead and copper for 32 days, followed by a feeding period of 40-50 days with uncontaminated lettuce, and the time-dependent distribution of the four metals during loading and unloading was determined in all major organs.
References
More filters
Journal ArticleDOI
The biology of oxygen radicals
TL;DR: The reactive superoxide radical, O2-, formerly of concern only to radiation chemists and radiobiologists, is now understood to be a normal product of the biological reduction of molecular oxygen.
Journal ArticleDOI
Iron Transport and Storage Proteins
P Aisen,I Listowsky +1 more
TL;DR: The iron binding affinities of the sites, and the two-domain hypothesis of tronsfemn structure, are described.
Journal ArticleDOI
The use of biological indicator organisms to monitor trace metal pollution in marine and estuarine environments—a review
TL;DR: A review of the use of indicator organisms to study trace metal pollution can be found in this paper, where it is suggested that the macroalgae and bivalve molluscs are the most efficient and reliable indicators developed to the present time.
Journal ArticleDOI
The relative affinities of ligand atoms for acceptor molecules and ions
Journal ArticleDOI
Metallothioneins and their role in the metabolism and toxicity of metals
TL;DR: The metallothioneins may also have an important role in regulating the normal absorption and homeostasis of zinc and copper as discussed by the authors, however, it is paradoxical, in that a protein synthesized within the cell to reduce toxicity, may, in itself, be toxic when excreted or leaked out from a cell to the extracellular space.