Figure 2

Analysis of untagged SSO0551 purification. A – Various purification steps followed by SDS-PAGE. SDS-PAGE was performed on a 4–12% gradient Novex bis-tris acrylamide gel (Invitrogen) and stained with BlueSafe Coomassie solution (Biorad). Lane M, molecular weight markers; Lane 1, cell-free extract of E. coli Rosetta(DE3)(pLysS)(pSBTN-AB30) ; Lane 2, soluble proteins from cell-free extract; Lane 3, soluble proteins after the 60°C heat treatment; Lane 4, Resource-S eluate ; Lane 5, Superdex75 eluate. Bands corresponding to recombinant SSO0551 polypeptide are indicated with the arrow. B – SSO0551 mass measurement by MALDI-TOF mass spectrometry. Measurements from 250 laser shots of purified protein cristallized with sinapinic acid were averaged.