CHAPTER 11: NMR Studies of Protein–Glycosaminoglycan Interactions

Glycosaminoglycans (GAGs) are a class of linear, sulfated polysaccharides. These extracellular polysaccharides interact with a range of protein partners and are active in controlling important biological phenomena, including reproduction, cell growth and differentiation, blood coagulation and immune system activation. As a result, interests in developing methods to control specific protein–GAG interactions are high. However, little high-resolution structural information on protein–GAG interactions is available, and predicting a protein’s specificity for different GAG motifs remains challenging. Solution NMR has played crucial roles in analyzing specificity and dynamics of protein–GAG interactions. It is instrumental in determining GAG-binding sites of proteins and elucidating GAG-induced changes in protein dynamics. NMR’s adaptability to GAG size and sulfation density means the technique can be used to investigate a large class of protein–GAG interactions even if homogeneous GAG samples are not available. In this chapter we will review some of the popular NMR techniques for studying protein–GAG interactions will be reviewed. Challenges in the study of protein–GAG systems and new techniques that may help in overcoming these challenges will also be examined.