Ion protein binding

Figure 14.8 Simple diagram of release of neurotransmitter and recycling of the vesicles in presynaptic neurone. After exocytosis, the membrane recycles to form a new vesicle which is re-filled with neurotransmitter. The Ca ion binding protein may control packaging, formation of fusion pore and release of neurotransmitter.

Metal ions Metal ion binding proteins (metalloproteins)... 

Using the Forster energy transfer equations (16), one can calculate that Co2+ and Tb3+ are 13.7 A apart, in excellent agreement with the value of 13.7 A from the protein x-ray structure. This technique should be valuable for future applications to other multimetal ion binding proteins and enzymes. 

Schafer BW, Fritschy JM, Murmann P, Troxler H, Durussel I, Heizmann CW, Cox JA. 2000. Brain S100A5 is a novel calcium-, zinc-, and copper ion-binding protein of the EF-hand superfamily. J Biol... 

For biological samples, for example, metal ion binding proteins, the native metal ion must be exchanged with a suitable PAC isotope. 

Hf, "in, and Mo have been applied to study iron ion and molybdenum ion containing proteins, respectively. Finally, " Cd and " Hg have been used in studies of de novo designed heavy metal ion binding proteins and proteins involved in bacterial heavy metal resistance.Other applications include cadmium and indium binding to bovine serum albumin and DNA, as well as in vivo experiments on bacteria. " ... 

An elaborate cellular defence system against oxygen-free radical toxicity exists, which includes, in a first line, factors that prohibit the formation of, or scavenge primary initiators of the lipid peroxidation process, such as metal-ion-binding proteins or the enzymes superoxide dismutase (SOD),... 

Fig. 7 Crystal structures of proteins that interact with metal minerals, a iron-oxide clusters on the interior surface of DpsA, b close up view of the nucleation center 11, c tii Hf-oxo cluster, and d penta Hf-oxo cluster at the di-tyrosyl nucleation motif of fenic-ion-binding protein, Fbp. e cluster at an intersection of subunits in MoAVSto protein...

Mikkelson, R.B. Wallach, D.F.H. (1976) Binding of Fluorescent Lanthanides to Rat Liver Mitochondrial Membranes and Calcium Ion-binding Proteins , Biochimica et Biophysica Acta, 433, 674-83... 

Calcium ions have been found to be used as a secondary messenger in secretory cells which are stimulated by extracellular ligands. The increase in the concentration of fr-ee Ca ions initiates exocytosis causing the secretory vesicles to fuse with the plasma membrane and release their contents to the exterior. It appears that ATP is required for exocytosis as well as the Ca " " ion flux and it is also likely that a Ca ion-binding protein such as the recently discovered calmodulin is required. Calmodulin is clearly a very important protein since it has been found in every plant and animal cell so far examined and has been highly conserved in the course of... 

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