Figure 2

SDS-PAGE (A) and western blot analysis (B, C) of expressed and purified recombinant proteins. (A) SDS-PAGE analysis of the expression of rAtpD and rP1-C in E. coli extracts (lanes 2 and 3 for rAtpD and rP1-C, respectively) and of the purified recombinant proteins (lanes 4 and 5 for rAtpD and rP1-C, respectively). Two irrelevant his-tagged proteins of the same mass as rAtpD (lane 6) and rP1-C (lane 7) were purified and included in the study. (B, C) Western blot analysis of the expression of rAtpD and rP1-C in E. coli extracts (lanes 2 and 3, respectively), of the purified recombinant proteins (lanes 4 and 5 for rAtpD and rP1-C, respectively) and of the two irrelevant his-tagged proteins of the same mass as rAtpD (lane 6) and rP1-C (lane 7) with a pool of 10 serum samples from M. pneumoniae-positive patients (B) and with a pool of 10 healthy blood donors (C). Lanes: 1, standard protein marker; 2, induced rAtpD (about 50 kDa); 3, induced rP1-C (about 40 kDa); 4, purified rAtpD; 5, purified rP1-C; 6, irrelevant his-tagged protein of the same mass as rAtpD; 7, irrelevant his-tagged protein of the same mass as r P1-C. The numbers on the left indicate molecular masses (in kDa).