Mutations affecting the repressibility of arginine biosynthetic enzymes in Saccharomyces cerevisiae.
Mutations affecting the repressibility of arginine biosynthetic enzymes in Saccharomyces cerevisiae.
复制标题
影响酿酒酵母精氨酸生物合成酶抑制性的突变。
DOI：
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发表时间：
1970
期刊：
影响因子：
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通讯作者：
J. Wiame
中科院分区：
文献类型：
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作者：
J. Béchet;M. Grenson;J. Wiame
本发明描述了一种分离酿酒酵母突变体的方法，所述酿酒酵母突变体已经丧失了外源精氨酸对鸟氨酸转氨甲酰酶的抑制性。
除了渗透性突变体，三个互补的突变类型被发现：argRI，argRII和argRIII，这是隐性的，并定义三个位点。没有证据表明这三个位点之间的任何一个连锁或与编码鸟氨酸转氨甲酰酶的基因。
在这些位点的突变不能区分的表型基础上的菌株：在基本培养基上生长后，L-鸟氨酸氨基甲酰转移酶活性是野生型菌株的两倍，突变既不改变生长速率，也不改变精氨酸的渗透性。
这些突变可能会影响异源多肽脱辅基阻遏物的结构。
在二倍体中的鸟氨酸转氨甲酰酶的水平与调节以及非调节细胞中的argF+基因的数目成比例。
A method is described for isolating mutants of Saccharomyces cerevisiae which have lost repressibility by exogenous arginine for ornithine transcarbamylase.
Besides permeability mutants, three complementary classes of mutations were found: argRI, argRII and argRIII which are recessive and define three loci. No evidence for a linkage between any of these three loci or with the gene coding for ornithine transcarbamylase has been obtained.
Strains bearing mutations at either of these loci cannot be distinguished on a phenotype basis: after growth on minimal medium, the l-ornithine carbamoyl transferase activity is twice that of the wild type strain; the mutations modify neither the growth rate nor the permeability to arginine.
The mutations might affect the structure of an hetero-polypeptidic aporepressor.
The level of ornithine transcarbamylase in diploids is proportional to the number of argF+ genes in regulated as well as in non-regulated cells.