Myoglobin physiology

THE OXYGEN DISSOCIATION CURVES FOR MYOGLOBIN HEMOGLOBIN SUIT THEIR PHYSIOLOGIC ROLES... 

Rice-Evans, C., Okunade, G. and Khan, R. (1989). The suppression of iron release from activated myoglobin by physiological electron donors and desferrioxamine. Free Rad. Res. Commun. 7, 45-54. 

The first four materials (IRMM/IFCC-452, 453, 454, 455) are expected to be released during 2000. Projects on the certification of reference materials for cardiac marker (myoglobin) and total protein concentration in serum are under discussion. Even so the number of available CRMs for clinical chemistry and occupational toxicology is still limited. This has to do with the complexity of physiological compounds (e.g. proteins), the instabihty (e.g. enzymes), or the volatility (e.g. solvents). 

The PDOS of the iron in deoxy- and CO-myoglobin and of myoglobin with different degrees of water content was also determined by Achterhold et al. [112, 113]. They found that the modes with an energy larger than 3 meV (24 cm ) are harmonic at physiologically relevant temperatures. Those below 3 meV exhibit a... 

Kagen, L. J. Myoglobin. Biochemical, Physiological, and Clinical Aspects Columbia Univ. Press, 1973, p. 151. 

Figure 7. Release profile from sonicated capsules. Samples that were to be treated with sonic energy were placed in the polypropylene cages and immersed in 10 ml of physiological saline in scintillation vials. The vials were subjected to 3 minutes of sonication at 4 C in a sonic bath. The capsules were then transferred to fresh buffer and the release of myoglobin was followed (- -) and compared with release from capsules containing free myoglobin (-x-).

The facility of metal complex formation is underscored by the fact that most porphyrin systems with any type of physiological function occur as metal complexes (e.g. Fe in hemoglobins, myoglobins, cytochromes, catalases and peroxidases Mg in chlorophylls and bacteriochlorophylls Co in vitamin B12). 

It is also safe to say that, because of the great complexity of proteins, even of the simplest, most well-characterized proteins, such as insulin, lysozyme, and myoglobin, and because of the very wide range of proteins present in most physiologic environments, very simplistic hypotheses and mechanisms are generally not very applicable. 

---