Aim: To explore the purification methods of wild-type and recombinant suilysin and to evaluate their biological activities.
Methods: Wild-type suilysin was purified by ammonium sulfate precipitation, anion-exchange chromatography and hydrophobic chromatography in turn, while recombinant suilysin was first refolded and purified by immobilized metal ion affinity chromatography, and further purified by Thiopropyl Sepharose 6B. The biological activities were evaluated by hemolysis test, cytotoxicity assay.
Results: Both prepared wild-type and recombinant suilysin, with purify over 90%, have hemolysis activity and could injure target cells at high concentration while cholesterol could completely inhibit their activities.
Conclusion: Recombinant suilysin has similar biological activities with wild-type suilysin, and this work contributed to further study the functions of suilysin on pathogenesis of steptococcus suis.