Proline biosynthesis in Saccharomyces cerevisiae: molecular analysis of the PRO1 gene, which encodes gamma-glutamyl kinase.
Proline biosynthesis in Saccharomyces cerevisiae: molecular analysis of the PRO1 gene, which encodes gamma-glutamyl kinase.
复制标题
酿酒酵母中脯氨酸的生物合成：编码 γ-谷氨酰激酶的 PRO1 基因的分子分析。
DOI：
10.1128/jb.174.12.4148-4156.1992
复制
发表时间：
1992
影响因子：
3.2
通讯作者：
Brandriss,MC
中科院分区：
文献类型：
--
作者：
Li,W;Brandriss,MC
酿酒酵母的PRO1基因编码428个氨基酸的蛋白质γ -谷氨酰激酶（ATP:L-glutamate 5-phosphotransferase, EC 2.7.2.11），是脯氨酸生物合成的第一步。氨基酸序列比较表明，酵母和大肠杆菌γ -谷氨酰激酶在整个长度上具有显著的同源性。在PRO1上游区域发现了4个与GCN4蛋白结合的一致序列和1个与RAP1蛋白结合位点密切匹配的序列。通过测量稳态mRNA水平和PRO1- lacz基因融合编码的β -半乳糖苷酶活性来分析PRO1基因对生长培养基变化的响应。PRO1的表达不受外源脯氨酸的抑制，也不受生长培养基中谷氨酸的诱导。尽管PRO1基因的表达在组氨酸饥饿下没有变化，但gcd1菌株的稳态PRO1 mRNA水平和β -半乳糖苷酶活性均升高，而gcn4菌株的稳态PRO1 mRNA水平和β -半乳糖苷酶活性均降低。此外，在gcn4菌株背景下，pro1缓养菌株对脯氨酸完全缺乏营养。这些结果表明PRO1受一般氨基酸控制系统的调控。
The PRO1 gene of Saccharomyces cerevisiae encodes the 428-amino-acid protein gamma-glutamyl kinase (ATP:L-glutamate 5-phosphotransferase, EC 2.7.2.11), which catalyzes the first step in proline biosynthesis. Amino acid sequence comparison revealed significant homology between the yeast and Escherichia coli gamma-glutamyl kinases throughout their lengths. Four close matches to the consensus sequence for GCN4 protein binding and one close match to the RAP1 protein-binding site were found in the PRO1 upstream region. The response of the PRO1 gene to changes in the growth medium was analyzed by measurement of steady-state mRNA levels and of beta-galactosidase activity encoded by a PRO1-lacZ gene fusion. PRO1 expression was not repressed by exogenous proline and was not induced by the presence of glutamate in the growth medium. Although expression of the PRO1 gene did not change in response to histidine starvation, both steady-state PRO1 mRNA levels and beta-galactosidase activities were elevated in a gcd1 strain and reduced in a gcn4 strain. In addition, a pro1 bradytrophic strain became completely auxotrophic for proline in a gcn4 strain background. These results indicate that PRO1 is regulated by the general amino acid control system.