Hansen H, Roggenkamp R
Institut für Mikrobiologie der Heinrich-Heine-Universität Düsseldorf, Federal Republic of Germany.
Eur J Biochem. 1989 Sep 1;184(1):173-9. doi: 10.1111/j.1432-1033.1989.tb15004.x.
A mutant of the methanol-utilizing yeast Hansenula polymorpha defective in catalase was isolated. It lacks the ability to grow on methanol as the sole source of carbon and energy due to a loss of peroxisomal function that is required for the dissimilation and assimilation of this substrate. Growth of the mutant on glucose or glycerol was not impaired. Transformation of mutant cells with the gene coding for catalase A from Saccharomyces cerevisiae [Cohen, G., Fessl, F., Traczyk, J., Rytka, J. & Ruis, H. (1985) Mol. Gen. Genet. 200, 74-79] conferred constitutive expression of catalase activity. When the gene was placed under control of the regulatory methanol oxidase promoter from H. polymorpha, high levels of activity subject to glucose repression were obtained. In both cases efficient targeting of catalase A to the heterologous peroxisomes and assembly into an active form could be demonstrated. Concomitantly, growth on methanol was restored in the transformed mutant. The results are in line with a high conservation of transport signals on peroxisomal proteins. Expression of a cytosolic catalase in H. polymorpha did not confer the ability to grow on methanol. Therefore, proper localization of the catalase activity is a prerequisite for peroxisomal function.
分离出了一种过氧化氢酶缺陷的利用甲醇的多形汉逊酵母突变体。由于该底物异化和同化所需的过氧化物酶体功能丧失，它缺乏以甲醇作为唯一碳源和能源生长的能力。该突变体在葡萄糖或甘油上的生长未受影响。用编码来自酿酒酵母的过氧化氢酶A的基因转化突变细胞[科恩，G.，费斯尔，F.，特拉齐克，J.，里特卡，J. & 鲁伊斯，H.（1985年）《分子遗传学与普通遗传学》200卷，74 - 79页]，可导致过氧化氢酶活性的组成型表达。当该基因置于来自多形汉逊酵母的调节性甲醇氧化酶启动子控制下时，可获得受葡萄糖阻遏的高水平活性。在这两种情况下，都能证明过氧化氢酶A有效地靶向异源过氧化物酶体并组装成活性形式。同时，转化后的突变体恢复了在甲醇上的生长。这些结果与过氧化物酶体蛋白上转运信号的高度保守性一致。在多形汉逊酵母中表达胞质过氧化氢酶并不能赋予其在甲醇上生长的能力。因此，过氧化氢酶活性的正确定位是过氧化物酶体功能的一个先决条件。
