Kim K W, Kamerud J Q, Livingston D M, Roon R J
Department of Biochemistry, University of Minnesota, Minneapolis 55455.
J Biol Chem. 1988 Aug 25;263(24):11948-53.
Purified preparations of asparaginase II of Saccharomyces cerevisiae exhibit two protein bands upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Cloning and sequencing of the ASP3 gene, and partial amino acid sequencing as asparaginase II, imply that both bands are encoded by ASP3 but have different N termini. Northern blot analysis using the cloned ASP3 gene as a probe indicates that nitrogen catabolite repression of asparaginase II is achieved by alteration in mRNA levels. Deletion of sequences greater than 600 base pairs upstream from the initiation AUG codon results in an altered response to certain nitrogen sources in strains containing the truncated gene.
酿酒酵母天冬酰胺酶II的纯化制剂在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳中呈现两条蛋白带。ASP3基因的克隆与测序以及天冬酰胺酶II的部分氨基酸测序表明，这两条带均由ASP3编码，但N端不同。使用克隆的ASP3基因作为探针进行的Northern印迹分析表明，天冬酰胺酶II的氮代谢物阻遏是通过mRNA水平的改变实现的。从起始AUG密码子上游删除大于600个碱基对的序列会导致含有截短基因的菌株对某些氮源的反应发生改变。
