Expression, Purification and Characterization of Recombinant Human Arginase 1 in Escherichia coli

Arginase is an enzyme that catalyzes the degradation of arginine to produce urea and ornithine, which is crucial in the urea cycle. As a kind of half essential amino acid, arginine is only necessary for the rapid growth organizations, such as the growth of tumor tissue. Arginase could deprive the nutrition of tumor cells through catalyzes the degradation of arginine. There are two kinds of arginases: arginase 1 and arginase 2. Arginase 1 is expressed predominantly in the liver, while arginase 2 is expressed in non-hepatic tissues, with the highest levels of expression in the kidneys. In this article, we first cloned human arginase 1 to the pT7 high expression level vector, then we over-expressed arginase 1 by the auto-induction system. The expressed recombinant His10-arginase1 was purified by Ni-NTA affinity chromatography and Mono Q anion exchange chromatography. The typical yield of recombinant arginase 1 was 48.5 mg from 1 liter culture medium with purity above 95%. The recombinant His10-arginase1's activity was 128 U/mg. Our research may facilitate further research of arginase 1's biological activity and its role in the related diseases.