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为研究大肠杆菌（Ｅ．ｃｏｌｉ）精氨酰－ｔＲＮＡ合成酶（ＡｒｇＲＳ）的结构与功能的关系，用基因突变法将２４５和２５２位的两个Ａｒｇ分别缺失，得到了突变基因ａｒｇＳΔｒ２４５，ａｒｇＳΔｒ２５２。对ａｒｇＳΔｒ２４５的表达和变种酶的性质进行了研究。野生型基因在大肠杆菌中以可溶性蛋白的形式表达，而缺失了Ａｒｇ２４５的突变酶ＡｒｇＲＳΔＲ２４５在大肠杆菌中形成了包涵体蛋白。包涵体蛋白复性后，酶的比活约为４０单位／毫克，为天然酶活力的０．３％。通过对复性酶和天然酶的吸收光谱、差光谱和ＤＴＮＢ巯基滴定分析，发现ＡｒｇＲＳΔＲ２４５结构松散，生色基团暴露，这可能是酶形成包涵体蛋白和活力下降的主要原因。
In order to study the relationship between structure and function of arginyl-tRNA synthetase (ArgRS) in E. coli, the ArgSΔr245 and argSΔr252 were obtained by deleting the two Arg at position 245 and 252 respectively by gene mutation. The argSΔr245 expression and the properties of the variant enzymes were studied. The wild-type gene was expressed as a soluble protein in E. coli whereas the ArgRSΔR245 mutant lacking Arg245 formed inclusion bodies in E. coli. Inclusion body protein renaturation, the specific activity of the enzyme is about 40 units / mg, 0.3% of the natural enzyme activity. Absorption spectrum, differential spectroscopy and DTNB thiol titration analysis of renaturation enzyme and natural enzyme showed that the structure of ArgRSΔR245 was loose and chromophore was exposed. This may be the main reason for the formation of inclusion body protein and decreased activity of enzyme.