FIG. 5.

Western blot of total cellular proteins extracted from different E. coli strains. ETEC strains 117/86, 147/1, TX-1, and 469ST harbor the tib locus, whereas ETEC isolate G1253 does not. DAEC 2787 expressing the AIDA system serves as a positive control. Proteins were separated by SDS-10% PAGE. Modified proteins were identified with anti-AIDA-I serum recognizing the heptosyl modification. Solid arrowheads, AIDA proprotein and modified AIDA-I adhesin; open arrowhead, modified TibA protein. Molecular sizes of the marker proteins are given in kilodaltons.