Heme proteins, roles

W. A. Bulen, J. R. LeComte, R. C. Bums, and J. Hinkson, in A. San Pietro, ed., Non-Heme Iron Proteins Role in Lnerg Conversion Antioch Press, Yellow Springs, Ohio, 1965, p. 261. 

The importance of metals has been long known but it is only in the past three decades that some of their specific roles have begun to be elucidated. It is perhaps not surprising that iron, the most naturally abundant of all metals, should play many important roles in nature. We shall present here one small aspect of this rapidly expanding area of inorganic chemistry, namely that of the functioning of iron when coordinated to porphyrins CL, 2, 3). Figure 2 shows the major heme proteins... 

Mortenson, L.E. Nitrogen fixation in extracts of Clostridium pasteurianum. In Non-heme Iron Proteins Role in Energy Conversion,... 

Cytochromes serve as electron donors and electron acceptors in biological electron transfer chains, and with >75,000 members (53) they provide the bulk of natural heme proteins in biology. Cytochromes may be fixed into place within an extended electron transfer chain, such as the membrane-bound 6l and 6h of the cytochrome bci complex, or may be soluble and act as mobile electron carriers between proteins, for example, cytochrome c (54). In either role, the cytochrome may be classified by the peripheral architecture of the porphyrin macrocycle. Figure 1 shows the dominant heme types in biological systems, which are hemes a, b, c, and d, with cytochomes b and c being most prevalent. The self-association of a protein with heme via two axial ligands is a... 

A number of NO-derived reactive species can initiate lipid peroxidation, including nitrogen dioxide and, most notably, ONOO , which displays unique properties as a mediator of lipid oxidation. On a molecular basis, ONOO is a more potent lipid oxidant than hydrogen peroxide and, unlike H2O2, it does not require metal catalysis. The one-electron oxidants such as metals, as well as heme proteins and peroxynitrite, are assumed to play an important role in many diseases associated with oxidative stress. Heme proteins such as horseradish peroxidase (HRP) can produce alkylperoxyl radicals through two sequential... 

Craven, P. A., DeRuberts, F. R., and Pratt, D. W. (1979). Electron spin resonance study of the role of NO catalase in the activation of guanylate cyclase by NaN, and NH2OH. Modulation of enzyme responses by heme proteins and their nitrosyl derivatives.). Biol. Chem. 254, 8213-8222. 

Phillips, W, D., Knight, E., Jr.,Blomstrom, D. C. In Non-Heme Iron Proteins Role in Energy Conversion, p. 69 edited by San Pietro, A. Yellow Springs, Ohio Antioch Press 1965. 

Spectroscopy plays an important role in characterizing the structure and integrity of proteins adsorbed on electrodes. For heme proteins, the Raman spectrum is a sensitive probe of the spin state, thus providing an insight into the integrity of... 

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