Expression and purification of recombinant MBP- Pf Ctr369Nt-S. Expression of MBP-Pf Ctr369Nt-S was targeted to the E. coli periplasm. A. Steps in the isolation of recombinant MBP-Pf Ctr369Nt-S were analysed on a 12.5% reducing SDS-PAGE. Western blot of A. probed with either anti-MBP B. or anti-PF14_0369 antibodies C. In all panels: lane 1, total E. coli lysate; lane 2, periplasmic proteins; lanes 3–5 represent proteins that did not bind, were washed from and eluted off the amylose resin, respectively. Molecular markers are shown to the left of each image.