2004 Karl Meyer Award Winner

William J. Lennarz, Ph.D.
Distinguished Professor, Department of Biochemistry and Cell Biology
Director, Institute for Cell and Developmental Biology

Research Description: Biosynthesis and catabolism of glycoproteins

Our laboratory is interested in understanding several steps involved in glycoprotein synthesis, including N-glycosylation and protein folding, as well as the functions of the glycan chains. We are using yeast, a simple eukaryotic organism that can be genetically manipulated, to study glycoprotein assembly. More specifically, we are investigating the enzymatic processes of oligosaccharide addition and removal that occur in nascent polypeptides and misfolded glycoproteins, respectively ( fig.1 ). Evidence has been obtained that the enzyme PNGase associates with the proteasome during proteolysis of glycoproteins. In addition, PDI, the enzyme that catalyzes folding and disulfide bond formation in glycoproteins, is being studied ( fig.2 ). The crystal structure has been obtained and now we are studying the role of the various domains of this protein in its catalytic activity.