(A) SDS PAGE of M. catarrhalis OMP of the strains O35E, 300 and 415 together with their respective m35 knock-out mutants. Black triangles show the position of the M35 protein band at 36 kDa. White triangles show the position of the 40 kDa protein. The spectra display the intensity of each protein band determined by the AlphaEaseFC® software. Light lines show the wild-type strain, dark lines show the respective M35 mutant strains. (B) Western Blot analysis for human salivary IgA against M35 of the strains O35E, 300 and 415 from seven healthy donors. The isogenic m35 mutants were included as negative controls.