Examination of Regulatory Cross-talk Between the Decay Accelerating Factor-binding Fimbrial/Afimbrial Adhesins and Type I Fimbriae

The revised sequence of DaaA means that the protein is 98% identical to the afimbrial adhesin regulator AFAA-III. While PapB repressed FimB OFF to ON switching in strain AAEC370A, this was not the case for DaaA. PapB, but not DaaA, reduced the level of expression of type 1 fimbriae, in static LB media. Attention is now focused on the amino terminus of the PapB protein as the possible domain involved in cross talk with type 1 fimbriae.