Kunert J
Department of Biology, Medical Faculty, Palacký University, Olomouc, Czechoslovakia.
Folia Microbiol (Praha). 1988;33(3):188-97. doi: 10.1007/BF02925904.
All the 16 strains of dermatophytes tested here metabolized cystine (3 mmol/L) in two glucose-peptone media with a different C: N ratio. Cystine was utilized as a sulfur source and, in addition, as a carbon and nitrogen source, in parallel with growth. Excess sulfur was excreted to the medium after its oxidation as inorganic sulfate and sulfite. In a physiologically alkaline medium the growth was fast and was accompanied by a pH increase and cystine was utilized intensively. Eleven species used up all cystine available. Sulfate was the main oxidation product, sulfite was produced at a low concentration, at the beginning of growth in particular. Only traces of thiol compounds (cysteine) were present in the medium. In a physiologically acid medium growth was soon limited by a decreased pH (below 5.0) but cystine continued to be utilized at an identical rate. All cystine was used up by 5 species. The tendency to produce sulfite in addition to sulfate further increased and sulfite was often the predominant product. Concentrations of thiol compounds were also substantially higher. Thus, dermatophytes can utilize cystine even under conditions that do not support good growth and increase the sulfite production.
在此测试的所有16种皮肤癣菌菌株，在两种具有不同碳氮比的葡萄糖蛋白胨培养基中均能代谢胱氨酸（3 mmol/L）。胱氨酸被用作硫源，此外，还与生长同时用作碳源和氮源。过量的硫在氧化为无机硫酸盐和亚硫酸盐后被排泄到培养基中。在生理碱性培养基中，生长迅速，伴随着pH值升高，胱氨酸被大量利用。11个菌种耗尽了所有可用的胱氨酸。硫酸盐是主要的氧化产物，亚硫酸盐在生长开始时特别是在低浓度下产生。培养基中仅存在痕量的硫醇化合物（半胱氨酸）。在生理酸性培养基中，生长很快受到pH值降低（低于5.0）的限制，但胱氨酸仍以相同的速率被利用。5个菌种耗尽了所有胱氨酸。除硫酸盐外产生亚硫酸盐的趋势进一步增加，亚硫酸盐常常是主要产物。硫醇化合物的浓度也显著更高。因此，即使在不支持良好生长的条件下，皮肤癣菌也能利用胱氨酸并增加亚硫酸盐的产生。
