Oxygen carriers, binding

Pancreatic ribonuclease Staphylococcal nuclease Peroxidases Glutathione peroxidase Cytochrome c peroxidase Oxygen carriers Myoglobin, hemoglobin Myohemerythrin, hemerythrin Hormone-binding proteins Uteroglobin Pre albumin Lectins... 

The best characterized and thus prototypical of the binuclear iron-oxo proteins is hemerythrin (Hr), an oxygen carrier from some classes of marine invertebrates, such as sipunculids. The protein consists of several identical 13 kDa subunits which contain two iron atoms and reversibly bind one molecule of O2. Myohemerythrins contain a single 13 kDa subunit (25,26,27). 

Basdo etall00 found that the attachment of Fe(II)(TPP) to a rigid modified silica gel support produced an efficient oxygen carrier. The silica gel used contained a 3-imidazolylpropyl group bonded to the surface atoms of silicon. This then reacted with Fe(lI)(TPP)(B)2, and the axial base was removed by heating the silica gel. The five-coordinate Fe(II)(TPP) complex 41 was prepared. The open coordination site could reversibly bind molecular oxygen. It was concluded that... 

One promising approach to facilitated transport pioneered by Nishide and coworkers at Wasada University is to chemically bind the oxygen carrier to the polymer backbone, which is then used to form a dense polymer film containing no solvent [28], In some examples, the carrier species is covalently bonded to the polymer matrix as shown in Figure 11.29(a). In other cases, the polymer matrix contains base liquids which complex with the carrier molecule through the base group as shown in Figure 11.29(b). Because these films contain no liquid solvent, they are inherently more stable than liquid membranes and also could be formed into thin films of the selective material in composite membrane form. So far the selectivities and fluxes of these membranes have been moderate. 

It is the oxygen-carrier protein found in marine invertebrates it binds oxygen reversibly in a manner similar to Hb and Mb. Several oligomers are known, but a diiron subunit is common to all of them. 

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