Luther J P, Lipke H
Appl Environ Microbiol. 1980 Jul;40(1):145-55. doi: 10.1128/aem.40.1.145-155.1980.
A strain of Aspergillus fumigatus from composted coffee and garden wastes utilized natural deproteinized insect, banana, hair, octopus, and synthetic tyrosine and dopa melanins as sole sources of carbon. With a sucrose supplement, degradation was essentially complete after 50 days in Czapek medium pH 6.5 at 30 degrees C. The catabolic rate differed for each substrate pigment, as did the molecular weight distribution of products accumulating in the medium. After incubation with L-[U-14C]melanin, over 50% was recovered in a dark fungal pigment, the remainder appearing as cell protein, chitin, lipid, CO2, and polar metabolites. When grown on melanin, the normally pale mycelia darkened with the production of a fungal allomelanin, with infrared spectrum and alkali fusion products differing from those of the substrate pigment. Isotope distribution in amino acids for A. fumigatus grown on labeled melanin supplemented with sucrose suggested separate pools for synthesis of cell proteins and melanoproteins. Deposition of allomelanin increased resistance of conidia, sterigma, and conidiophores to lytic carbohydrases as judged by scanning electron microscopy.
从堆肥咖啡和花园废弃物中分离出的一株烟曲霉能够利用天然脱蛋白昆虫、香蕉、毛发、章鱼以及合成的酪氨酸和多巴黑色素作为唯一碳源。在添加蔗糖的情况下，于30℃、pH 6.5的察氏培养基中培养50天后，降解基本完成。每种底物色素的分解代谢速率不同，培养基中积累的产物的分子量分布也不同。用L-[U-¹⁴C]黑色素培养后，超过50%的黑色素以深色真菌色素的形式回收，其余部分则表现为细胞蛋白、几丁质、脂质、二氧化碳和极性代谢物。当在黑色素上生长时，通常浅色的菌丝体会因产生真菌异黑素而变黑，其红外光谱和碱熔产物与底物色素不同。在添加蔗糖的标记黑色素上生长的烟曲霉中，氨基酸的同位素分布表明细胞蛋白和黑素蛋白的合成有独立的库。通过扫描电子显微镜判断，异黑素的沉积增加了分生孢子、梗基和分生孢子梗对裂解碳水化合物酶的抗性。
