FIG. 2.

A Western blot, of an SDS-PAGE gel (7.5% polyacrylamide), probed with MAb 11C6. Total membrane proteins from iron-stressed M. catarrhalis 7169 (lane A), from wild-type E. coli BM25.8 (lane B), and from transformed E. coli BM25.8 expressing rOMP B1 (lane C) were analyzed. Lane D contains the binding fraction from a holotransferrin affinity matrix that was incubated with total membranes of BM25.8 expressing rOMP B1, demonstrating that the recombinant protein retains transferrin binding activity. Molecular mass standards (left) are in kilodaltons.