Dr. Hans Bakker is a glycobiologist with expertise in glycosyltransferases. He received his Ph.D. at the VU Amsterdam, the Netherlands, and worked in Zurich, Switzerland, and Wageningen, the Netherlands, afterwards. Since 2001, he has worked at Hannover Medical School in Germany. Over the years, he has identified several new genes encoding glycosyltransferases, including the xylosyltransferases responsible for the glycosylation of Notch EGF repeats and, more recently, the first C-mannosyltransferase, the enzyme responsible for unique glycosylation of tryptophans in proteins. His laboratory has established several specific methods to characterize C-mannosyltransferases and their target proteins from Caenorhabditis elegans and mammals in vitro and cellular systems. After cloning the C-mannosyltransferase in 2013, he could establish that C-mannosylation assists in protein folding in the endoplasmic reticulum and is important for the temperature stability of proteins. Whereas C. elegans has one C- mannosyltransferase, four homologs are present in mammals. His group could show that different mammalian C-mannosyltransferases have distinct fine specificity.