1. Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
2. Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA.
3. Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
4. Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
5. Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA.
6. École polytechnique fédérale de Lausanne, 1015 Lausanne, Switzerland.
7. Cancer Center at Illinois, University of Illinois at Urbana-Champaign, Urbana, IL, USA.