Haemoglobin, reactions

Wlien a strong electron-donor ligand such as pyridine is added to tlie reaction mixture, it can bond so strongly to tlie Rli tliat it essentially drains off all tlie Rli and shuts down tlie cycle it is called a catalyst poison. A poison for many catalysts is CO it works as a physiological poison in essentially the same way as it works as a catalyst poison it bonds to tlie iron sites of haemoglobin in competition witli O. ... 

Absorption spectra of standard solutions of Cyt c was obtained at different concentration. Maximum of absolution was observed at wavelength 410 nm. It is known haemoglobin and other haems have absolution maximum at the same wavelength. For elaboration of selective method of Cyt c determination in semm of mice its reaction with phtalocyanine of copper was investigated. Absorption maximum of Cyt c with Cu phtalocyanine in H SO was observed at wavelength 710 nm. Dependence on optical density at 710 nm against concentration of Cyt c have linear character in range 0.162-10-"-6.49-10 mol/L. 

One of the most important reactions of dioxygen is that with the protein haemoglobin which forms the basis of oxygen transport in blood (p. 1099). Other coordination... 

The findings here surest that, after an initial slow phase corresponding to the antioxidant capacity of the LDL, hydroperoxides can interact with haemoglobin in a similar manner to hydrogen peroxide, forming ferryl haemoglobin, which is then rapidly reduced to mixtures consisting mainly of oxy- and met- forms, possibly by the synproportionation reaction, as proposed in the studies... 

Gutteridge, J.M.C. (1986). Iron promoters of the Fenton reaction and lipid peroxidation can be released from haemoglobin by peroxides. FEBS Lett. 201, 291-298. 

Copper is an essential micronutrient required in the growth of both plants and animals. In humans, it helps in the production of blood haemoglobin. In plants, copper is an important component of proteins found in the enzymes that regulate the rate of many biochemical reactions in plants. Plants would not grow without the presence of these specific enzymes. Research projects show that copper promotes seed production and formation, plays an essential role in chlorophyll formation and is essential for proper enzyme activity, disease resistance and regulation of water in plants (Rehm and Schmitt, 2002). 

Solids were characterized by XRD, N2.BET surface area, and FT-IR. The antacid capacity of the synthesized zeolites was evaluated using the methodology reported by Rivera et al. [7] and Linares et al. [6]. The pepsin enzymatic activity was determined by the reaction between a specific mass of the solid and a denatured haemoglobin solution [8]. 

In Fig. 3, the pepsin dissolved in HC1, without interaction with any solid, showed a maximum at 272 nm. After interaction with the disordered cancrinite and the intermediate phase, a small decrease in the absorbance maximum of the pepsin spectrum was observed. This small decrease is due to the pepsin adsorption on the solid surfaces. The pepsin activity was also determined by the proteolysis reaction of a denatured haemoglobin solution at different times. Fig. 4 shows the obtained results. One can see, that the enzymatic activities (determined as absorbance), presented by the tested solids were very similar among them. These results show that pepsin enzymatic activity is not lost after the contact the pepsin with the tested solids. Therefore, the absorbance decrease observed in Fig. 4, is produced by the pepsin adsorption on the tectosilicate surface, and not by chemical reactions between pepsin and the tectosilicates... 

Gow, A. J., Stamler, J. S., Reactions between nitric oxide and haemoglobin... 

In this method the keyhole limpet haemoglobin conjugate was prepared as follows Keyhole limpet haemocyanin (KLH, Calbiochem, La Jolia, CA) and bovine serum albumin (BSA, BDH Chemicals) were coupled to the adduct (2), derived from 6-bromohexanoic acid and monoquat (3), via a carbodiimide reaction, as reported previously by Niewola et al. [184], The resulting conjugates contained 662mol of Paraquat per mole of KLH and 15mol of Paraquat per mole of 6-bromohexanoic acid. The amount of Paraquat bound to the protein was determined by spectrophotometric dithionite assay for Paraquat and the protein concentration was established by a standard Lowry test. 

The principles of ESR spectroscopy are very similar to NMR spectroscopy but the technique gives information about electron delocalizations rather than molecular structure and it enables the study of electron transfer reactions and the formation of paramagnetic intermediates in such reactions. In some situations, information regarding molecular structure can be obtained when suitable prosthetic groups are part of a molecule, e.g. FMN (flavin mononucleotide) in certain enzymes or the haem group in haemoglobin. Sometimes it is possible to attach suitable groups to molecules to enable their reactions to be monitored by ESR techniques. Such spin labels as they are called, are usually nitroxide radicals of the type... 

A. J. Gow, J. S. Stamler, Reactions between Nitric Oxide and Haemoglobin under Physiological Conditions , Nature 1998, 391, 169-173. 

The dye bromthymol blue will react with haemoglobin at a large number of sites. If haem-haem interaction is functioning the reaction occurs several times faster w ith reduced haemoglobin than with oxyhaemoglobin. If haem-haem interaction is destroyed by digestion with carboxypeptidase A this difference disappears. In the case of the carboxy-... 

Although it seemed highly probable that this structural change was the result of the oxygenation reaction and not a species difference this remained to be proved. X-ray analysis of a recently discovered crystalline form of reduced horse haemoglobin removed this uncertainty 40). 

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