The Society for Glycobiology is pleased to announce that the recipient of the 2013 Karl Meyer Award is Markus Aebi. The Karl Meyer Award was established in 1990 to honor the distinguished career of Karl Meyer and his outstanding contributions to the field of Glycobiology. This international award is presented to well-established scientists with currently active research programs who have made widely recognized major contributions to the field of Glycobiology.
Dr. Markus Aebi (Professor, Swiss Federal Institute of Technology, Zurich, Switzerland) has been a pioneer in the application of yeast genetic tools to identify the enzymes involved in endoplasmic reticulum N-glycosylation. His interest for glycobiology started with the serendipitous identification of the essential subunit WBP1 of yeast oligosaccharyltransferase. This discovery was rapidly followed by the description of several components of the eukaryotic oligosaccharyltransferase complex, thereby unraveling the intricate regulatory mechanisms underlying the transfer of oligosaccharides to nascent glycoproteins. The work of Dr. Aebi also led to the description of a novel class of mannosyltransferases and glucosyltransferases that utilize dolichol-phosphate-mannose and dolichol-phosphate-glucose for the assembly of the lipid-linked oligosaccharide substrate of oligosaccharyltransferase. The genetic and biochemical characterization of these endoplasmic reticulum glycosyltransferases established the structural requirements for recognition of lipid-linked oligosaccharides by oligosaccharyltransferase. Similar applications of yeast genetics yielded essential insights on the importance of dolichol recycling for N-glycosylation and on the function of N-linked carbohydrates in the processing of glycoproteins. Dr. Aebi showed that defined N-glycan structures serve as signals in the quality control process that leads to the degradation of misfolded proteins in the endoplasmic reticulum, an important step forward in the deciphering of the "glyco-code" of eukaryotic cells. The use of the model system Saccharomyces cerevisiae was not only instrumental for the detailed description of the conserved pathway of N-linked protein glycosylation in eukaryotes but also provided the necessary tools to identify and describe multiple types of human congenital disorders that affect this process.
A step forward in the understanding of N-linked protein glycosylation was achieved by the discovery of a general protein glycosylation system in the bacterium Campylobacter jejuni. The research team of Dr. Aebi transferred the biosynthetic pathway from Campylobacter into the model system Escherichia coli and described this N-glycosylation pathway at a molecular level. Most importantly, it was shown that the eukaryotic and the bacterial N-glycosylation are homologous processes, making it possible to decipher the molecular mechanisms of N-linked protein glycosylation in the bacterial system. This achievement also made possible the development of a bacterial expression system capable of producing recombinant human-type glycoproteins. This outstanding research work culminated in the publication of the structure of the bacterial oligosaccharyltransferase and the formulation of a reaction mechanism for the N-glycosylation process (in collaboration with the group of Kaspar Locher, ETH Zurich).
Dr. Aebi has the remarkable ability to integrate the outcome of his research in a broad biological context. Along this line, the description of fungal galectins has been related to the defense mechanisms of fungi against predation or the description of endoplasmic reticulum-associated protein degradation has been interpreted in the context of membrane homeostasis and cell viability. In addition to being an outstanding scientist, Dr. Aebi is an enthusiastic teacher and mentor and greatly contributed to the visibility of glycobiology by promoting junior researchers in the field.
For his seminal contributions to the field of glycobiology, both in high impact research in defining the mechanisms of protein glycosylation and quality control as well as carbohydrate-based defense mechanisms in fungi, Markus Aebi represents the very best in the field and thus has been awarded the 2013 Karl Meyer award from the Society for Glycobiology.