FIG. 2.

Dihydrofolate reductase fusions are not secreted by the type III machinery of Y. enterocolitica. (A) The drawing depicts the primary structures of hybrid polypeptides as follows: line 1, YopE_1-15-DHFR, yop codons 1 to 15 fused to DHFR; line 2, YopE_1-220-DHFR, yop codons 1 to 220 (full-length) fused to dihydrofolate reductase (DHFR). (B) Y. enterocolitica strains W22703 (wild type) and LC1 Δ(sycE1) were transformed with plasmids described above, and type III secretion was analyzed by immunoblotting with specific antibody (α-DHFR, α-YopR, or α-Cat) as described in the legend to Fig. 1.