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在高表达大肠杆菌精氨酰ｔＲＮＡ合成酶（ＡｒｇＲＳ）基因（ａｒｇＳ）５５０倍的基础上，将ａｒｇＳ的编码起始位点经基因定点突变导入ＮｃｏＩ限制性内切酶的位点后，重组到受异丙基硫代－β－Ｄ－半乳糖苷（ＩＰＴＧ）诱导的ｐＴｒｃ９９Ｂ质粒上，使ａｒｇＳ比受体菌表达高近２０００倍。通过一步ＤＥＡＥ－Ｓｅｐｈａｒｏｓｅ柱层析则可得到ＳＤＳ－ＰＡＧＥ一条带的ＡｒｇＲＳ，比活为１５０００ｕ／ｍｇ，与文献值相同。虽重组过程中ＡｒｇＲＳ第二位氨基酸残基由天冬酰胺变为天冬氨酸，产生了变种酶ＡｒｇＲＳ２ＮＤ，但这种改变既不影响ＡｒｇＲＳ的活力和动力学常数，也不影响它的热稳定性和在变性剂中的稳定性。
Based on the 550-fold high expression of the ArgRS gene (argS) of Escherichia coli, the coding start site of argS was introduced into the site of NcoI restriction enzyme by site-directed mutagenesis and then recombined into ArgS was nearly 2000-fold more potent than the recipient bacteria on the pTrc99B plasmid induced by isopropylthio-β-D-galactoside (IPTG). By one-step DEAE-Sepharose column chromatography, a band of ArgRS of SDS-PAGE was obtained with a specific activity of 15000u / mg, which is the same as the reference value. Although the second amino acid residue of ArgRS was changed from asparagine to aspartic acid during the process of recombination, a variant enzyme ArgRS2ND was produced, but this change neither affected the kinetic and kinetic constants of ArgRS nor affected its thermal stability Sex and stability in denaturants.