Fonzi W A, Sypherd P S
Mol Cell Biol. 1985 Jan;5(1):161-6. doi: 10.1128/mcb.5.1.161-166.1985.
Diploid cells of Saccharomyces cerevisiae homozygous for the spe1A mutation, which eliminates ornithine decarboxylase activity, were found to sporulate at a greatly reduced frequency in the absence of polyamines. Plasmids which complement the spe1A mutation were isolated by their ability to restore sporulation competence to these cells. Three distinct plasmids were isolated. Each plasmid insert overlapped the same 8.0-kilobase region, and each plasmid restored ornithine decarboxylase activity to spe1A mutants. These plasmids also conferred ornithine decarboxylase activity to Escherichia coli EWH319 from which the ornithine decarboxylase gene is deleted. The plasmid-encoded activity expressed in E. coli resembled S. cerevisiae ornithine decarboxylase in its kinetic characteristics, indicating that the yeast ornithine decarboxylase gene was cloned. Southern blot analysis suggested that ornithine decarboxylase is a single-copy gene in S. cerevisiae. A single 2.1-kilobase transcript was demonstrated by Northern blot analysis.
对spe1A突变纯合的酿酒酵母二倍体细胞（该突变消除了鸟氨酸脱羧酶活性）发现在缺乏多胺的情况下以大大降低的频率形成孢子。通过其恢复这些细胞形成孢子能力的能力分离出补充spe1A突变的质粒。分离出三种不同的质粒。每个质粒插入片段重叠相同的8.0千碱基区域，并且每个质粒将鸟氨酸脱羧酶活性恢复到spe1A突变体。这些质粒还赋予来自缺失鸟氨酸脱羧酶基因的大肠杆菌EWH319鸟氨酸脱羧酶活性。在大肠杆菌中表达的质粒编码活性在其动力学特性上类似于酿酒酵母鸟氨酸脱羧酶，表明酵母鸟氨酸脱羧酶基因被克隆。Southern印迹分析表明鸟氨酸脱羧酶在酿酒酵母中是单拷贝基因。Northern印迹分析证明了一个单一的2.1千碱基转录本。
