Aim To optimize purification conditions of recombinant hirudin 3 in thefermentation broth and characterize the product. Methods Reambinant hirudin 3 was isolated andpurified from the fermentation broth by three column chromatography steps with macroporous resin,DEAE cellulose DES2 and preparative RP-HPLC, respectively, and the optimal conditions were obtained.Purity of the product was determined by SDS-PAGE and analytical RP-HPLC. The molecular weight wasdetermined by mass spec-trometry. The structure of the product was analyzed by peptide map.ResultsThe product with purity of 95.4786% was obtained after three purification steps in the optimumconditions with a total yield of 39%. The molecular weight of the product was 6 913.32 ± 6.55 Da,coincident to the theoretical molecular weight of r-hirudin 3. The structure of the product wascoincident to r-hirudin 3 either. Conclusion The optimized purification steps can be successfullyemployed for purification of r-hirudin 3 from E. coli using batch-type approaches. The productobtained with high purity was confirmed to be r-hirudin 3.
Aim To investigate the anticancer activity of two new cytotoxins from thevenom of Agkistrodon acutus. Methods The venom was isolated by FPLC column chromatography consistingof DEAE Sepharose FF and Source 30S. The cytotoxic activity on tumor cells was detected by MITmethod. Purity and molecular weight were determined by SDS-PAGE (silver staining). Their stabilitiesto temperature and pH were also detected. Results Two pure cytotoxins named ACTX-6 and ACTX-8 wereobtained. Their molecular weights are 98 kDa and 27 kDa, respectively. ACTX-6 consists of twosubunits bonded together by disulfide bonds. Conclusion ACTX-6 and ATCX-8 have highest inhibitoryactivity on lung cancer cell A549. ACTX-6 is stable to heat while ACTX-8 not. ACTX-6 is stablebetween pH 7-9 and ACTX-8 between pH 6 - 9.