Article

Crystal Structures of the Outer Membrane Domain of Intimin and Invasin from Enterohemorrhagic E. coli and Enteropathogenic Y. pseudotuberculosis

National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Structure (Impact Factor: 6.79). 05/2012; 20(7):1233-43. DOI: 10.1016/j.str.2012.04.011
Source: PubMed

ABSTRACT Intimins and invasins are virulence factors produced by pathogenic Gram-negative bacteria. They contain C-terminal extracellular passenger domains that are involved in adhesion to host cells and N-terminal β domains that are embedded in the outer membrane. Here, we identify the domain boundaries of an E. coli intimin β domain and use this information to solve its structure and the β domain structure of a Y. pseudotuberculosis invasin. Both β domain structures crystallized as monomers and reveal that the previous range of residues assigned to the β domain also includes a protease-resistant domain that is part of the passenger. Additionally, we identify 146 nonredundant representative members of the intimin/invasin family based on the boundaries of the highly conserved intimin and invasin β domains. We then use this set of sequences along with our structural data to find and map the evolutionarily constrained residues within the β domain.

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