Figure 2
Expression of His 6 -tagged mature SnOLP in E. coli , solubilization and purification. A. SDS-PAGE analysis of the expression of His6-tagged mature SnOLP in E. coli cultures incubated at 37°C for 3 h and induced by 0.4 mM IPTG (when indicated). 1. Molecular mass marker (LMW, Amersham Pharmacia Biotech); 2. Total protein fraction from non-induced E. coli culture; 3. Total protein fraction from IPTG-induced E. coli culture; 4. Soluble protein fraction from IPTG-induced E. coli culture; 5. Insoluble protein fraction from IPTG-induced E. coli culture. B. Western blot analysis of expressed His6-tagged mature SnOLP probed with His6-monoclonal antibody. 6. Soluble protein fraction from IPTG-induced E. coli culture; 7. Insoluble protein fraction from IPTG-induced E. coli culture. C. SDS-PAGE analysis of insoluble His6-tagged mature SnOLP which was urea solubilized and subsequently purified by immobilized-metal (Ni2+) affinity chromatography (IMAC). 8 and 9. Eluates from IMAC. In A. and C. the gels were stained with Coomassie brilliant blue. His6-tagged mature SnOLP protein is indicated by arrow heads.