Complex carbohydrate recognition by proteins: Fundamental insights from bacteriophage cell adhesion systems

Protein–glycan interactions are ubiquitous in nature. Molecular description of complex formation and the underlying thermodynamics, however, are not well understood due to the lack of model systems. Bacteriophage tailspike proteins (TSP) possess binding sites for bacterial cell surfaces oligosaccharides. In this article we describe the analysis of TSP-oligosaccharide complexes. TSP provide large glycan interaction sites where affinity and specificity are guided by the protein surface solvation and the conformational space sampled by the respective glycan. Furthermore, we describe a computational approach to analyse the conformational space sampled by flexible glycans of bacterial origin, a prerequisite for a thorough understanding of TSP-oligosaccharide interactions.