Melanin
of Melanine (griech. μέλας „“) brown or black pigments ( color means ) are black, which result from the enzymatic oxidation of the Tyrosins (enzymatic Bräunung) and with humans the colouring of the skin, hair or eyes cause. They come into vertebrate animals and insects, as color means intothe ink of Tintenfischen and also in micro organisms and plants forwards. Melanin is formed with vertebrate animals in the Melanozyten of the skin and in the retina of the eye. Melanin arises with humans particularly in two variantsone brown/blackish (Eumelanin), itself ofthe amino acids Tyrosin and Dopa derive and a brighter/yellowish/reddish (Phäomelanin) variant, which is schwefelhaltig. There are also different colour variants, so-called Allomelanine, which develop from Hydroxybenzolen. These predominantly are in plants, mushrooms and bacteria. The Melanine nearly always appear as mixing types andare additionally linked with Lipiden or protein.
The Melanin in the human skin and the hair are combinations from Eumelaninen and the schwefelhaltigen Phaeomelaninen. The mixing proportion of these two Melanintypen is contributing for the Hauttyp of humans. The content of Phaeomelanin is in low-red hairparticularly highly and decreases over brown and black hair. Melanin forms in the skin increased during sun exposure and probably serves as light protection before the harmful influence of the UV-RADIATION. One of the main arguments for the UV protective function is the observation that strongly pigmented groups of populationsin smaller measure of sun-induced skin cancer (Melanom) get sick than more weakly pigmented subpopulations. However for a long time the high illness rate is well-known for Melanome with rothaarigen persons, so that this Melanintyp possibly sensitizes the skin rather instead of it to protect.
By genetic assessment and/or. through in the runthe time acquired damage to the hereditary substance the synthesis of the Melanins can be disturbed. If production is blocked, then also the color means in skin, hair and eyes are missing, whereby a very bright white skin, an unusually bright hair color and red eyes result. One speaksfrom Albinismus and calls the organisms concerned Albinos. With overproduction step increased dark marks in the skin on (liver marks, summer rungs, nut/mother marks), which (malignant Melanom ) to become malicious to be able.
