Garrett J M
Department of Biology, Hamilton College, Clinton, New York 13323.
J Gen Microbiol. 1989 Sep;135(9):2429-37. doi: 10.1099/00221287-135-9-2429.
A new class of Saccharomyces cerevisiae mutants (aat1 - amino acid transport) has been identified. These mutants are unable to grow on rich medium or on minimal medium supplemented with certain amino acids (isoleucine, methionine, phenylalanine, tyrosine or valine). This phenotype is directly linked to the presence of the leu2 allele in these strains: aat1 LEU2 organisms grow normally on all media tested. Leucine uptake through the leucine-specific permease is inhibited to less than 35% of wild-type levels in aat1 cells preincubated in nonpermissive media, and the activity of the general amino acid permease is also low in these conditions. aat1 cells are therefore unable to grow on rich media because they cannot take up enough leucine to supplement their auxotrophic requirement.
已鉴定出一类新的酿酒酵母突变体（aat1 - 氨基酸转运）。这些突变体无法在丰富培养基上生长，也无法在添加了某些氨基酸（异亮氨酸、蛋氨酸、苯丙氨酸、酪氨酸或缬氨酸）的基本培养基上生长。这种表型与这些菌株中leu2等位基因的存在直接相关：aat1 LEU2生物体在所有测试培养基上均能正常生长。在非允许培养基中预孵育的aat1细胞中，通过亮氨酸特异性通透酶的亮氨酸摄取被抑制至野生型水平的35%以下，并且在这些条件下，一般氨基酸通透酶的活性也较低。因此，aat1细胞无法在丰富培养基上生长，因为它们无法摄取足够的亮氨酸来补充其营养缺陷型需求。
