木糖对马克斯克鲁维酵母菊糖酶合成的诱导作用

马克斯克鲁维酵母可利用木糖、菊糖等多种碳源。利用木糖为碳源时菊糖酶产量最高，酶活力可达30．4U／mg菌体（干重），菊糖次之；利用葡萄糖、乳糖等酶活力均很低。用洗涤菌体进行诱导试验也表明，木糖能诱导该酵母菌菊糖酶的合成，蛋白质合成抑制剂环已亚胺可抑制木糖对该 酶的诱导作用。在以木糖为碳源的生长培养基中添加葡萄糖能明显地阻遏菊糖酶的形成。试验结果表明，该菌株菊糖酶的合成受诱导和分解产物阻遏机制的双重调节，木糖是酵母菊糖酶合成的一种良好的天然诱导剂。

Induction of Inulinase Formation in Kluyveromyces marxianus by Xylose

Inulinase production by Kluyverom yces marxianus on various carb on sources was examined.The highest level of inulinase(30.4 U/mg cell dry wt.)wa s determined in the medium containing xylose,inulin also supported superior inul inase yield.While sone other carbon sources including glucose,lactose and so on, did not stimula te inulinase formation beyond basal levels.The enzyme can be induced in washed g lucose-grown cells by xylose, thus xylose was considered as a nature inducer.Inu linase induction by xylose was inhibited by cycloheximide.The enzyme induction w as subject to glucose repression.The regulation of inulinase in the investigated yeast can be considered as an induction and repression type.