Irwin M, Oates D C, Patterson D
Somatic Cell Genet. 1979 Mar;5(2):203-16. doi: 10.1007/BF01539161.
A new purine-requiring mutant of Chinese hamster ovary cells (CHO-Kl) is described. This mutant, Ade-G, grows on aminoimidazole carboxamide, hypoxanthine, or adenine. It complements all eight of our other previously described Ade- mutants. Biochemical analysis of de novo purine synthesis in whole cells suggests that Ade-G is capable of the first four reactions of de novo purine biosynthesis and that it synthesizes and accumulates phosphoribosylformylglycinamidine (FGAM). Direct enzyme assay in cell-free extracts confirms that Ade-G is defective in phosphoribosylaminoimidazole synthetase activity and does not convert FGAM to phosphoribosylaminoimidazole (AIR), the next intermediate in the de novo biosynthetic pathway.
本文描述了中国仓鼠卵巢细胞（CHO-K1）的一种新的嘌呤需求型突变体。该突变体Ade-G可在氨基咪唑甲酰胺、次黄嘌呤或腺嘌呤上生长。它能与我们之前描述的其他8种Ade-突变体互补。对全细胞中嘌呤从头合成的生化分析表明，Ade-G能够进行嘌呤从头生物合成的前四个反应，并且它能合成并积累磷酸核糖甲酰甘氨脒（FGAM）。无细胞提取物中的直接酶活性测定证实，Ade-G在磷酸核糖氨基咪唑合成酶活性方面存在缺陷，无法将FGAM转化为磷酸核糖氨基咪唑（AIR），而AIR是从头生物合成途径中的下一个中间产物。
