中国生物工程杂志

Augmenter of liver regeneration (ALR) is a kind of hepatocyte growth factor .To study the expression, purification and bioactivity of human augmenter of liver regeneration (rhALR) in Pichia Pastoris, the expression plasmid pPICZαA- ALR was constructed and transformed into P. Pastoris by the method of electroporation transformation. Induced with 0.5% methanol, the 30 kD protein in the culture supernatant of recombinant P. Pastoris was confirmed to be rhALR by SDS-PAGE and Western blot. Quantitative analysis showed that the target protein was in a level of 66% of the total protein of the culture supernatant, with a yield of 40mg/L.we had performed DEAE anion exchange chromatography two times with excessive and regular adsorption quantity consecutively, and then the rhALR above 95% purity and 52% protein recovery could be obtained by G75 molecular sieve chromatography at last step. The bioactivity assay of the purified product showed that rhALR could stimulate the proliferation of HepG2, SMMC-7721 and NIH-3T3 in vitro.