My research group is working in the areas of bioorganic chemistry, synthetic carbohydrate chemistry, glycobiology, and immunology. Our current research is centered on protein glycosylation, one of the most ubiquitous posttranslational modifications of proteins in eukaryotes. It is estimated that half of total human proteins are glycoproteins. Thus, glycosylation adds a new level of structural and functional diversity of proteins and expands the biological information of an otherwise concise human genome. We combine synthetic organic chemistry, structural biology, and immunology to understand the roles of glycans in biological processes, and how glycosylation affects a protein’s structure and function. Three research projects are going on in my laboratory: 1) Development of new chemoenzymatic methods for synthesizing oligosaccharides and glycoproteins; 2) Structural and mechanistic study of endoglycosidases and glycosynthases; and 3) chemical glycobiology of HIV with an emphasis on exploring envelope glycoproteins for HIV vaccine design.