Biological systems myoglobin

Biological systems Ligand-myoglobin Protein dynamics Bacteriorhodopsin Light harvesting Pigment-protein complexes Photosynthetic reaction centers... 

An excellent review of methods of measurement of CO in biological systems has been published [1], The rate of CO release from CO-RMs is dependent on conditions, with myoglobin frequently producing faster CO release than pure water or a phosphate buffer. Many CO-RMs are oxygen and light-sensitive so that it is important that measurements are carried out in the absence of 02 and/or light. Most measurements are carried out at 37°C. Manometric and GC measurements rely on the low solubility of CO in water. At 1 atm CO, the solubility is ca. 1 mM in pure water at 25°C [229]. This does not normally cause problems as experimental conditions produce a low partial CO pressure and the gas space is normally larger than the solution space. 

Redox proteins are relatively small molecules. In biological systems they are membrane associated, mobile (soluble) or associated with other proteins. Their molecular structure ensures specific interactions with other proteins or enzymes. In a simplified way this situation is mimicked when electrodes are chemically modified to substitute one of the reaction partners of biological redox pairs. The major classes of soluble redox active proteins are heme proteins, ferredoxins, flavoproteins and copper proteins (Table 2.1). In most cases they do not catalyze specific chemical reactions themselves, but function as biological (natural) electron carriers to or between enzymes catalyzing specific transformations. Also some proteins which are naturally not involved in redox processes but carry redox active sites (e.g., hemoglobin and myoglobin) show reversible electron exchange at proper functionalized electrodes. 

SERS has been used for the study of molecules of biological importance, such as nucleic acid components.The adsorption on a silver electrode was considered in some way similar to the adsorption to the charged membranes in biological systems. The adsorption of a nucleic acid itself was also studied with SERS." We have already discussed the work of Cotton et at2i8,2i9,22i who studied Cytochrome C and myoglobin. SERS requires only small quantities of material, which is very suitable for biological studies. 

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