Structure of Melanin

Mason, H. S., Structure of melanins, in Pigment Cell Biology, Gordon, M., Ed., Acadenaic Press, New York, 1959, 563. 

Commonly, light enhances the rate of many reactions, probably because of the increased population of radicals and/or other favorable changes in the structure of melanin molecules. Thus, photoinduced changes have been reported in redox equilibria established between melanin and nitroxides (Section IV) (579) these may result from a photochemical effect on redox potentials of either one or both com-... 

The ion-exchange capability of various types of melanins allows binding of the Fe isotope, the most common probe used in Mossbauer spectroscopy. This method has proved to be a useful and accurate technique in the investigation of molecular and supramolecular structures of melanins. Both natural sepia and bovine eye melanins, as well as synthetic [Pg.300]

Despite the lack of knowledge of the precise molecular structure of melanins, many of their physical properties can be understood in terms of the electronic structure. Thus, the optical and electrical behaviors of melanins and melanosomes, which are consistent with the role observed or hypothesized in vivo, can be interpreted in terms of the formalism of the solid-state theory. 

Nicolaus [10] and Mason [11] have described our current knowledge of the structure of melanic pigments, the most preponderant pigments of human hair. Two theories are still considered for the structure of melanin, and both consider structures involved in Raper s scheme (Figure 4-26) [54, 55], as intermediates in the formation of all melanic pigments. Nicolaus [56] has proposed that melanin is a complex random polymer (Figure 4-27), formed from several species of the Raper scheme. This is the favored scheme at this time. 

Melanin is the molecule that is responsible for skin color in humans. It s also what gives your eyes and hair their color. There isn t one single structure of melanin, rather it refers to a whole class of highly colored molecules that are all derived from the amino acid tyrosine. 

An analytical approach to studying the structure of melanin, by Nicolaus and co-workers 184, 204) led to the concept of melanin as a... 

Bridelli M, Capelleti R, Crippa PR (1981) Electret State and Hydrated Structure of Melanin. Bioelectrochem Bioeng 8 555... 

Hempel K (1966) Investigation on the Structure of Melanin in Malignant Melanoma with H- and C-Dopa Labelled at Different Positions. In Della Prota G, Muhlbock O (eds.) Structure and Control of Melanocytes, p. 162. Springer, Berlin Heidelberg New York... 

Kirby GW, Ogunkoya L (1965) Structure of Melanin Derived from ( )-3,4-Dibydroxy-f C, H]-phenylalanin by Oxidation with Tyrosinase. Chem Commun 21 546... 

Piattelli M, Fattorusso E, Magno S, Nicolaus RA (1963) The Structure of Melanins and Melanogenesis, III The Structure of Sepiomelanin. Tetrahedron 19 2061 and refs, therein... 

Pullman A, Pullman B (1961) The Band Structure of Melanins. Biochim Biophys Acta 54 384... 

Mason, H. S. 1953. The structure of melanins. In Pigment Cell Growth, Proceedings of the Third Conference on the Biology of Normal and Atypical Pigment Cell Growth. Academic Press, New York, pp. 277-303. 

Nicolaus RA, Piattelli M, Fattorusso E (1964) The structure of melanins and melanogenesis-IV on some natural melanins. Tetrahedron 20 163-172... 

Piattelli M, Fattomsso E, Nicolaus RA, Magno S (1965) The structure of melanins and melanogenesis-V. Ustilago melanin. Tetrahedron 21 3229-3236... 

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