High-yield purification and characterization of recombinant human leukotactin-1 in Pichia pastoris

The human chemokine, the short version of leukotactin-1 (ShLkn-1; molecular weight = 7.2 W and 66 amino acids), was expressed and secreted into a culture medium using the methylotrophic yeast, Pichia pastoris. The recombinant shLkn-1 was purified from the culture supernatant using a simple two-step procedure consisting of cation exchange and reverse phase chromatography (RPC), in which shLkn-1 was highly purified (99.5%) with a high recovery yield of 82.7%. The C-terminal truncated derivative of shLkn-1 was found in the supernatant and was separated by RPC. The physicochemical properties of the purified shLkn-1 were verified to be the same as expected. The biological activity of the purified recombinant shLkn-1 was also quantified using a chemotaxis assay. It was observed that the recombinant shLkn-1 had the maximum migration activity at a concentration of 10 nM, as potent as MIP-1alpha.