Wartmann T, Erdmann J, Kunze I, Kunze G
Institut für Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany.
Arch Microbiol. 2000 Apr;173(4):253-61. doi: 10.1007/s002030000137.
The dimorphism of the yeast Arxula adeninivorans LS3 is regulated by cultivation temperatures. Up to 42 degrees C the yeast grows as budding cells, which turn to mycelia at higher temperatures. To test whether the dimorphism is exclusively induced by high temperatures or also by other conditions, mutants were selected with an altered behaviour with respect to dimorphism. After mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine, five of 25,000 colonies formed a very rough surface consisting of mycelia at 30 degrees C, in contrast to the wild-type. These mutants allow temperature-mediated and morphology-related effects on gene expression and protein accumulation to be distinguished. Budding cells and mycelia showed different expression of genes encoding secretory proteins at the same temperature. Mycelia secreted two-fold more protein than budding cells, including the enzymes glucoamylase and invertase. This indicated that morphology, rather than temperature, is the decisive factor in the analysed processes.
嗜腺嘌呤阿苏酵母LS3的二态性受培养温度调控。在高达42摄氏度的温度下，该酵母以芽殖细胞形式生长，而在更高温度下则转变为菌丝体。为了测试二态性是仅由高温诱导还是也受其他条件影响，选择了在二态性方面行为改变的突变体。用N-甲基-N'-硝基-N-亚硝基胍诱变后，25000个菌落中有5个在30摄氏度时形成了由菌丝体组成的非常粗糙的表面，这与野生型不同。这些突变体使得能够区分温度介导的以及与形态相关的对基因表达和蛋白质积累的影响。在相同温度下，芽殖细胞和菌丝体显示出编码分泌蛋白的基因的不同表达。菌丝体分泌的蛋白质比芽殖细胞多两倍，包括葡糖淀粉酶和转化酶。这表明在分析的过程中，形态而非温度是决定性因素。
