Mayser P, Wille G, Inkampe A, Thoma W, Arnold N, Monsees T
Zentrum für Dermatologie und Andrologie, Justus-Liebig-Universität Giessen, Germany.
Mycoses. 1998;41 Suppl 2:74-7. doi: 10.1111/j.1439-0507.1998.tb00607.x.
A new minimal medium consisting only of L-tryptophan (L-trp) and a lipid source induced formation of brown pigmentation only in the species Malassezia furfur. Strains of the species M. sympodialis and M. pachydermatis failed to grow on this medium. Pigmentogenesis was already induced in M. furfur by 0.01 g% tryptophan, the pH optimum was pH = 5. Alternative amino nitrogen sources given concurrently with trp suppressed pigmentogenesis. The extract of the culture exhibited remarkable fluorescence, and several indole derivatives with a broad spectrum of colors were detected by means of mass spectroscopy and NMR. This finding may have an impact on the clinical appearance of pityriasis versicolor, a very common skin disease caused by lipophilic yeasts of the genus Malassezia. We hypothesize that in pityriasis versicolor metabolic adaptation of Malassezia yeasts to altered nitrogen conditions on superficial skin might be of pathophysiological importance. Tryptophan as inductor of pigmentogenesis probably cumulates during excessive sweating, a well known manifestation factor of pityriasis versicolor.
一种仅由L-色氨酸（L-trp）和脂质源组成的新型基本培养基仅在糠秕马拉色菌中诱导形成褐色色素沉着。合轴马拉色菌和厚皮马拉色菌菌株在此培养基上无法生长。0.01 g%色氨酸即可在糠秕马拉色菌中诱导色素生成，最适pH为pH = 5。与色氨酸同时提供的替代氨基氮源会抑制色素生成。培养物提取物表现出显著的荧光，通过质谱和核磁共振检测到几种具有广泛颜色的吲哚衍生物。这一发现可能会影响花斑癣的临床表现，花斑癣是一种由马拉色菌属亲脂性酵母引起的非常常见的皮肤病。我们假设在花斑癣中，马拉色菌酵母对皮肤表面改变的氮条件的代谢适应可能具有病理生理学重要性。色氨酸作为色素生成的诱导剂可能在多汗时积累，多汗是花斑癣的一个众所周知的表现因素。
