Bundles of insights into sugar transporters

Abstract

The structure of a bacterial protein belonging to the 'sugar porter' family guides the building of long-sought molecular models of proteins that transport glucose across cell membranes in humans. See Article p.361 Proteins that transport glucose across cellular membranes are essential for glucose metabolism in many organisms, from microbes to mammals. This Article reports three X-ray crystal structures of XylE — an Escherichia coli homologue of the GLUT family of human proteins — in complex with D-xylose, D-glucose and 6-bromo-6-deoxy-D-glucose. Structure-based modelling of GLUT1–4 enabled the authors to map known disease-related mutations, and the structural and biochemical information reported here provides a framework for understanding the molecular mechanism by which membrane proteins transport glucose and other sugars.