Caroline D F
J Bacteriol. 1969 Dec;100(3):1371-7. doi: 10.1128/jb.100.3.1371-1377.1969.
A new series of pyrimidine-requiring mutants of Neurospora has been isolated and all enzymes involved in pyrimidine biosynthesis are represented by at least one mutant. Among these mutants is included a single isolate for a new locus, pyr-6. This mutant is deficient in dihydroorotase (DHOase) and represents the only enzymatic step in orotate synthesis for which no mutant previously had been found. This mutant, which mapped genetically on the right arm of linkage group V, is unlinked to any of the other pyrimidine mutants. The DHOase-deficient mutant is also characterized by an unexpected growth behavior. The pyr-1 locus has been specifically associated with a lack of dihydroorotate dehydrogenase (DHOdehase). Mutants isolated in this series for other pyrimidine loci have been related to previously isolated mutants by allelism, recombination, and accumulation studies.
已分离出一系列新的需要嘧啶的脉孢菌突变体，参与嘧啶生物合成的所有酶至少由一个突变体代表。这些突变体中包括一个新基因座pyr-6的单一分离株。该突变体缺乏二氢乳清酸酶（DHOase），代表乳清酸合成中唯一尚未发现突变体的酶促步骤。该突变体在遗传图谱上位于连锁群V的右臂，与任何其他嘧啶突变体均无连锁关系。缺乏DHOase的突变体还具有意外的生长行为特征。pyr-1基因座与缺乏二氢乳清酸脱氢酶（DHOdehase）有特定关联。通过等位性、重组和积累研究，已将该系列中为其他嘧啶基因座分离的突变体与先前分离的突变体联系起来。
