Norovirus, glycans and attachment

Noroviruses engage glycans as essential attachment factors to promote infection of host cells. The past decade has witnessed significant progress in the field of norovirus research. Cell culture systems and animal models have become available, and structural biology and biophysics have significantly expanded our understanding of norovirus–glycan interactions. From crystallography, many high-resolution crystal structures are now available disclosing key elements of glycan recognition at atomic resolution. On this basis, NMR spectroscopy, native mass spectrometry, and biophysical techniques targeting membrane attached glycans have raised more intricate questions about the nature of norovirus–glycan attachment implying that a static picture of glycan recognition is insufficient. Linking novel biophysical observations to biological aspects of norovirus host cell entry is a challenge. Therefore, in a first step, this review summarizes and discusses recent biophysical approaches potentially paving the way to a dynamical picture of norovirus-glycan attachment. Novel insights from norovirus–glycan binding studies are put into perspective with current general developments in the field of protein–glycan interactions, hopefully provoking new ideas for norovirus research.