Metallothionein protein

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. 

As Teleosts, 3 species 28, 56, or 112 mg As/kg BW by sc injection All doses induced liver metallothionein protein within 24 h 23... 

These complexes are known with planar and non-planar M3X3 cores, and with tetrahedral or square-planar metal coordination. The X3M3 cycle in chair conformation and with tetrahedral metal coordination occurs in (p-SMe)3B3X6 (X = Cl, Br)38 and is proposed in the form of (p-Scys)3Cd3(Scys)6 for one of the two clusters with cysteinate coordination in metallothionein proteins.39 The twist-boat conformation occurs in S3Sn3Me640 and probably in the related compounds S3M3R6 (M = Ge, Sn, Pb R = Me, Bu, Ph).41 The same structural unit with distorted twist-boat stereochemistry occurs in the (p-S)3Fe3(Scys)5L cluster recently discovered in several ferredoxins.15 42... 

The activities of the purple fluid of the sea hare Aplysia dactylomela, such as toxic, antimicrobial and hemagglutinating properties, have been attributed to a substance of protein nature [332], Proteoglycans and adhesive glycoproteins present in the extracellular matrix of vertebrates, have also been reported in sponges. These molecules are probably involved in the cell adhesion systems of sponges [333], Recently, novel marine proteins have been reported, such as silicatein from sponge biosilica [334], and a metallothionein protein from the marine alga Fuats vesiculosus [335], Metallothioneins have also been isolated from Arctic... 

Whether specific storage forms are involved for the trace metals is debatable.107 Such a role has been alluded to for the non-exchangeable protein complexes in serum, i.e. caeruloplasmin for Cu, and a2-macroglobulin for Zn, and to metallothionein protein (Chapter 20.2). However, it has also been argued that there are sufficient deposits within body tissues to provide at least short-term storage of the minute quantities that are required. 

Karin, M. (1985). Metallothioneins proteins in search of function. Cell 41, 9-10. 

Metallothionein proteins are the most abundant intracellular, metal-binding proteins (Andrews, 2000). Four metallothionein isoforms have been identified in the mouse (MT-I-MT-IV) and are clustered within 50 kilobases of each other. In humans, there is one MTII gene and a cluster of MT I genes on chromosome 16 (Searl et al., 1984 West et al., 1990 Heuchel et al., 1995). The mammalian metallothioneins generally consist of 61 amino acids and 20 of these are cysteines (Heuchel et al., 1995). These cysteines are important for the binding of such bivalent metal ions, such as zinc, copper and cadmium. 

Butcher, H., W. Kennette, O. Collins, et al. 2003. A sensitive time-resolved fluorescent immunoassay for metallothionein protein. J. Immunol. Methods 272 247-256. 

Direct, nonsurfactant-mediated immobilization of metallothionein proteins [207-209] and streptavidin [210] at MWCNTs has also been carried out, the hydro-phobic regions of the proteins probably being responsible for the adsorption. Specific affinity binding of proteins to unmodified SWCNT sidewalls was demonstrated by the adsorption of monoclonal antibodies, IgG, specific for C60 fuller-enes, in aqueous solution. The affinity binding originated from the structural similarity of the tube sidewall graphite network and the C(M fullerene [221]. It was shown that the specific binding site of the IgG antibody is a domain of hydrophobic amino acids. 

Cd can also induce a number of protective mechanisms in the cell. Cd has been shown to enhance metallothionein protein and HSP70 expression in a variety of renal and non renal cell types [183, 184]. 

Metallothionein protein, found extensively in the brain, contains zinc, and so does cysteine-rich intestinal protein (cysteine is an amino acid). RNA proteins contain zinc as part of their structures. RNA, a protein, directs cellular protein synthesis using patterns taken from the DNA in the cell nucleus. 

Mercury, tris(l,10-phenanthroline)-structure, 64 Mercury(II) complexes masking agent, 536 Mercury electrodes potential range aqueous solution, 480 Metal carbonyls structure, 16 Metallocenes nomenclature, 126,127 Metallochromic indicators, 554 Metallofluorescent indicators, 558 Metallothionein proteins, 142 Mettd-metal bonding, 137,169 gravimetry, 525 history, 21,23 nomenclature, 122, 123 Metal nitrosyls structure, 16 Metal-phthalein metallochromic indicator, 557 Metal template reactions, 416,433 equilibrium kinetic, 434 thermodynamic, 434 Methane, dichloro-... 

Karin M (1985) Metallothioneins proteins in search of function. Cell 41 9-10 Klug A, Rhodes D (1987) Zinc finger a novel protein motif for nucleic acid recognition. TIBS 12 464-469... 

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