<i>Aeromonas hydrophila</i> RTX adhesin has three ligand-binding domains that give the bacterium the potential to adhere to and aggregate a wide variety of cell types.

ABSTRACT: Bacteria often make initial contact with their hosts through the ligand-binding domains of large adhesin proteins. Recent analyses of repeats-in-toxin (RTX) adhesins in Gram-negative bacteria suggest that ligand-binding domains can be identified by the way they emerge from "split" domains within the adhesin. Here, using this criterion and an AlphaFold3 model of a 5047-residue RTX adhesin from Aeromonas hydrophila, we identified three different ligand-binding domains in this fibrillar protein. The crystal structures of the two novel domains were solved to 1.4 and 1.95 Å resolution, respectively, and demonstrate excellent agreement with their modeled structures. The other domain was recognized as a carbohydrate-binding module based on its beta-strand topology and confirmed by its micr

SUBMITTER: Ye Q 

PROVIDER: S-EPMC12077191 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature