Download MendeleyMrpH, a new class of metal-binding adhesin, requires zinc to mediate biofilm formation.
Jiang, W., Ubhayasekera, W., Breed, M.C., Norsworthy, A.N., Serr, N., Mobley, H.L.T., Pearson, M.M., Knight, S.D.(2020) PLoS Pathog 16: e1008707-e1008707
- PubMed: 32780778
- DOI: https://doi.org/10.1371/journal.ppat.1008707
- Primary Citation of Related Structures:
6Y4E, 6Y4F - PubMed Abstract:
Proteus mirabilis, a Gram-negative uropathogen, is a major causative agent in catheter-associated urinary tract infections (CAUTI). Mannose-resistant Proteus-like fimbriae (MR/P) are crucially important for P. mirabilis infectivity and are required for biofilm formation and auto-aggregation, as well as for bladder and kidney colonization. Here, the X-ray crystal structure of the MR/P tip adhesin, MrpH, is reported. The structure has a fold not previously described and contains a transition metal center with Zn2+ coordinated by three conserved histidine residues and a ligand. Using biofilm assays, chelation, metal complementation, and site-directed mutagenesis of the three histidines, we show that an intact metal binding site occupied by zinc is essential for MR/P fimbria-mediated biofilm formation, and furthermore, that P. mirabilis biofilm formation is reversible in a zinc-dependent manner. Zinc is also required for MR/P-dependent agglutination of erythrocytes, and mutation of the metal binding site renders P. mirabilis unfit in a mouse model of UTI. The studies presented here provide important clues as to the mechanism of MR/P-mediated biofilm formation and serve as a starting point for identifying the physiological MR/P fimbrial receptor.
Organizational Affiliation:
Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Uppsala, Sweden.
