Rothamsted Experimental Station, Biochemistry Department, AL5 2JQ, Harpenden, Herts.
Planta. 1983 Apr;157(3):254-8. doi: 10.1007/BF00405190.
The activities of glutamine synthetase (GS), nitrogenase and leghaemoglobin were measured during nodule development in Phaseolus vulgaris infected with wild-type or two non-fixing (Fix(-)) mutants of Rhizobium phaseoli. The large increase in GS activity which was observed during nodulation with the wild-type rhizobial strain occurred concomitantly with the detection and increase in activity of nitrogenase and the amount of leghaemoglobin. Moreover, this increase in GS was found to be due entirely to the appearance of a novel form of the enzyme (GSn1) in the nodule. The activity of the form (GSn2) similar to the root enzyme (GSr) remained constant throughout the experiment. In nodules produced by infection with the two mutant strains of Rhizobium phaseoli (JL15 and JL19) only trace amounts of GSn1 and leghaemoglobin were detected.
在感染野生型或两种非固氮（Fix(-)）突变体根瘤菌的菜豆中，测定了谷氨酰胺合成酶（GS）、固氮酶和豆血红蛋白的活性。在与野生型根瘤菌菌株共生结瘤过程中观察到的 GS 活性的大幅增加，与固氮酶的检测和活性增加以及豆血红蛋白的含量同时发生。此外，发现这种 GS 的增加完全是由于在根瘤中出现了一种新形式的酶（GSn1）。在整个实验过程中，类似于根酶（GSr）的形式（GSn2）的活性保持不变。在感染 Rhizobium phaseoli 的两种突变株（JL15 和 JL19）产生的根瘤中，仅检测到痕量的 GSn1 和豆血红蛋白。
