Yu Y G, Turner G E, Weiss R L
Department of Chemistry and Biochemistry, University of California, Los Angeles 90095-1569, USA.
Mol Microbiol. 1996 Nov;22(3):545-54. doi: 10.1046/j.1365-2958.1996.1321494.x.
A DNA clone which complemented an arg-14 mutation of Neurospora crassa was isolated by sib selection from a cosmid library (pMOcosX). Southern and restriction-fragment-length polymorphism (RFLP) analysis confirmed that the cloned DNA contained the arg-14 gene. The arg-14 gene was identified as the structural gene for acetylglutamate synthase by immunodepletion of enzyme activity with antibodies prepared against an arg-14 fusion protein and by the thermal instability of acetylglutamate synthase in a temperature-sensitive arg-14 mutant. The fungai acetylglutamate synthase has little sequence homology to its bacterial counterpart, unlike other arginine biosynthetic enzymes. Expression of the arg-14 gene is regulated by cross-pathway control similar to many amino acid biosynthetic genes. However, expression of acetylglutamate synthase occurs throughout the developmental growth cycle, unlike other arginine biosynthetic enzymes.
通过从黏粒文库（pMOcosX）中进行同胞选择，分离出了一个能互补粗糙脉孢菌arg - 14突变的DNA克隆。Southern杂交和限制性片段长度多态性（RFLP）分析证实，克隆的DNA包含arg - 14基因。通过用针对arg - 14融合蛋白制备的抗体进行酶活性免疫去除，以及在温度敏感的arg - 14突变体中乙酰谷氨酸合酶的热不稳定性，将arg - 14基因鉴定为乙酰谷氨酸合酶的结构基因。与其他精氨酸生物合成酶不同，真菌乙酰谷氨酸合酶与其细菌对应物的序列同源性很低。arg - 14基因的表达受类似于许多氨基酸生物合成基因的交叉途径控制。然而，与其他精氨酸生物合成酶不同，乙酰谷氨酸合酶的表达在整个发育生长周期中都有发生。
