Conservation of novel pathotype-specific antigens EtpA and EatA among phylogenically distinct strains expressing different colonization factors.

<p>a. Heatmap of EtpA and EatA showing the proportion of strains positive for expression of these antigens among different CF groups. CF antigen designation is shown at left of the heatmap. nd = no CF antigen detected. Below is the heatmap key depicting colors associated with each degree of antigen positivity. Density line in yellow depicts the relative number of map features assigned at each proportion. Primary data used to construct the heatmap can be found in <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003446#pntd.0003446.s007" target="_blank">S2 Dataset</a>. b. Imunoblot detection of EtpA and EatA expression among strains from different phylogenies. The upper immunoblot demonstrates EtpA production in the prototype H10407 strain, ThroopD isolated in Dallas, TX in 1975, the Juruá_18/11 (Amazon, 1998), and phylogentically dispersed strains from icddr,b. The <i>etpA</i> mutant is included as a negative control. The lower blot demonstrates EatA production by H10407, phylogenically distributed strains from icddr,b and Envira_10/1, an additional isolate from cholera-like outbreaks in the Amazon. The <i>eatA</i> mutant is included as a negative control. c. Phlyogram showing the phylogenetic distribution of selected ETEC strains (designations in blue) and reference E. coli strains (designations in black). Red circles and gold stars represent eatA+, and etpA+ strains, respectively.