Figure 2

Co-expression of ES fusion antigen with 0–4 copies of S antigen in P. pastoris . (A) Methanol-induced P. pastoris clones harboring the ES fusion gene in the background of 0, 1, 2 and 4 copies of the S gene were lysed and run on SDS-PAGE (lanes are indicated by the S gene copy number), followed by silver staining. An un-induced sample (of clone ES,S₄) was analysed in lane ‘U’. (B) The same samples as in ‘A’ were transferred onto a nitrocellulose membrane after SDS-PAGE, and subjected to immunoblotting with mAb 5S. (C) Immunoblot analysis similar to that shown in panel ‘B’, but probed using mAb 24A12. In all three panels, pre-stained protein markers were run in lanes ‘M’; their sizes in kDa are shown to the left of panel ‘A’. The arrows to the right indicate the positions of the ES fusion (upper) and the S (lower) antigens.