Figure 2

dOSCP1 forms dimers and trimers in solution. (A) Purified recombinant His-dOSCP1 protein was separated on SDS-PAGE containing 10% acrylamide. The gel was then stained with Coomassie Brilliant Blue G-250. Lane 1: Precision protein standards (Bio-Rad) with molecular weights given in kilodaltons. Lane 2: purified His-dOSCP1 protein. The arrow indicates the 35 kDa band. (B). Native PAGE analysis of the recombinant dOSCP1. Lanes 1 and 2: 2 μg or 4 μg of protein were treated with sample buffer containing no SDS, no β-mercaptoethanol and without boiling. The samples were separated on Native-PAGE containing 10% acrylamide. The gel was then stained with Coomassie Brilliant Blue G-250. The bands detected were at 35 kDa, 70 kDa and 100 kDa band. The 35 kDa band corresponds to His-dOSCP1 recombinant protein, the 70 kDa band likely represents the dimeric form and the 100 kDa band may represent a trimeric form. Lanes 3 and 4: 2 μg or 4 μg of protein were treated with SDS sample buffer containing 4% SDS and 10% β-mercaptoethanol in boiling water. Lane 3: the 70 kDa band is not detectable. Land 4: A faint 70 kDa band is evident. Lane 5: Precision protein standards (Bio-Rad) with molecular weights given in kilodaltons (kDa).