Dimer formation of ΔH-domain protein in solution.

<p>(A) The purified ΔH-domain protein (0.2 mg/ml) was loaded onto native-PAGE. M, protein marker; lane 1, ΔH-domain protein with 2% SDS; lane 2, ΔH-domain protein only; lane 3, ΔH-domain protein with 10 mM DTT. (B) The gel filtration profile of ΔH-domain protein at the final purification step is shown. Two peaks were observed upon analysis with a Superdex S75 16/60 column (GE Healthcare). The elution volume is indicated on the top of each peak. The elution volume of 79.70 ml corresponds to a dimer size (30 kDa) and 62.57 ml to a tetramer size (60 kDa). (C) SEC-MALLS analysis of ΔH-domain and full-length forms of <i>Co</i>MsrA. The refractive index (RI) of the column eluate is plotted as a function of time. The weight-averaged molecular weight (MW) of the material in the eluate is calculated from light-scattering measurements. The calculated molecular masses are 35,010 Da for the ΔH-domain protein and 24,570 Da for the full-length protein.