Fig. 2

Size analysis of refolded MucA’ protein. The purified MucA’ protein was gel-filtered on a Superdex 75 XK 16/60 column connected to the FPLC system. Upper: The apparent molecular weight of MucA’ protein was estimated based on the calibration curve obtained from separate runs of protein standards from the MW-GF-70 kit according to the manufacturers’ instructions (Sigma, MO). The molecular masses of standards are as follows: Bovine serum albumin, 66 kDa; carbonic anhydrase, 29 kDa; cytochrome C, 12.4 kDa; aprotinin, 6.5 kDa. The calculated molecular weight of MucA’ monomer is 13.6 kDa. Lower: Analysis of fractions eluted from the column on a 15% SDS-polyacrylamide gel stained with Coomassie Brilliant Blue R 250. The migration of molecular weight standards in the SDS-polyacrylamide gel is shown on the left. The mobility of molecular weight markers of the indicated molecular weights in the column, as determined in a separate run, is shown on the top of the gel