Gaillardin C, Heslot H
Mol Gen Genet. 1979 May 4;172(2):185-92. doi: 10.1007/BF00268281.
Eight strains devoid of homocitrate synthase activity were found among lysine requiring mutants of the yeast Saccharomycopsis lipolytica. Genetic analysis of these strains showed that they were all affected at the same locus LYS 1. Three lines of evidence suggest that this locus defines a structural gene for homocitrate synthase. First, the mutations show various degrees of intragenic complementation; it could be shown in some cases that the hybrid enzyme formed in vivo displayed modified properties in vitro. Second, reversion of some of these mutations can result in a modified enzyme (desensitized). Third, a feedback mutant of homocitrate synthase was directly isolated from the wild type strain, and shown to carry a single mutation at of near LYS 1. We also present here the first attempts at genetic fine mapping in Saccharomycopsis lipolytica.
在解脂耶氏酵母赖氨酸营养缺陷型突变体中发现了8株缺乏高柠檬酸合酶活性的菌株。对这些菌株的遗传分析表明，它们均在同一基因座LYS 1处受到影响。三条证据表明，该基因座定义了高柠檬酸合酶的结构基因。首先，这些突变表现出不同程度的基因内互补；在某些情况下可以表明，体内形成的杂合酶在体外表现出修饰后的特性。其次，其中一些突变的回复可导致酶的修饰（脱敏）。第三，直接从野生型菌株中分离出高柠檬酸合酶的反馈突变体，并显示在LYS 1附近携带单一突变。我们在此还展示了对解脂耶氏酵母进行遗传精细定位的首次尝试。
