The solution structure of PapGII from uropathogenic Escherichia coli and its recognition of glycolipid receptors

Abstract

Uropathogenic Escherichia coli (UPEC) is the primary cause of symptomatic urinary tract infection. The P-pili, a bacterial surface organelle, mediates the bacterial host-cell adhesion. The PapG adhesin has generated much interest in recent years, not only because of its clinical value, i.e. in the prevention of microbial adherence, but also because of its ability to promote virulence. Using multidimensional nuclear magnetic resonance (NMR) and deuteration we have determined the solution structure of the adhesin domain from PapGII (PapGII-198). The novel structure of PapGII-198 is composed of a large elongated jellyroll motif. Despite an automated search of the structural database failing to reveal any similar proteins, PapGII adhesin shares some structural similarities with FimH. Furthermore, interpretation of NMR-titration data has enabled us to identify the putative binding site for the globoseries of oligosaccharides. This work provides insight into UPEC pathogenesis as well as aiding the development of preventive therapies and the guidance of future mutagenesis programmes.