Jürgen Roth: Immunogold master

G lycosylation, the synthesis of branched sugar chains on proteins, is a posttranslational modifi ca-tion commonly found on membrane and secretory proteins. Glycosylation is important for proper protein folding, and the composition of the sugar chains can also be used to track a glycoprotein's maturation. When Jürgen Roth started working on glycoproteins, researchers had only recently begun probing the mechanisms and machinery of glycosylation using biochemical approaches. Roth applied his expertise in electron microscopy (EM) to develop methods for visualizing carbohydrates (1) and protein glycosylation. Using electron-dense colloidal gold particles covered with protein A to detect antibodies bound to thin sections by electron microscopy (2), Roth's seminal studies have shown where (3, 4) and why (5) protein glycosylation takes place. Yet there's still more work he wants to do, as we learned when we spoke with him recently at home on holiday in Switzerland. I understand you grew up in East Germany… Yes, that's right. Actually, I was born a year and a half before World War II ended, before the state of Thuringia was liberated by the American army and then left to the Russians. I grew up in what was initially the Rus-sian military zone, which later became the German Democratic Republic. What was it like growing up there? Those initial postwar years— and many years afterwards—were diffi cult for everybody. It was a hard life. We were not poor, but we were struggling. But my memories are of a happy early childhood. My parents had to earn a living, so I was not really supervised all day. I grew up outdoors. I think for a young kid there's nothing nicer than to be in the forest or a fi eld with friends. Of course, when I was young, I did not understand the political situation in East Germany. Sometimes people—including an uncle of mine—would disappear for years and then come back and not speak about what happened to them. The eye-opener for me as a young boy was June 17, 1953: the fi rst-ever uprising of the people against the Communist regime. I vividly remember the state of emergency. I was much older when they started to build the Wall in Berlin. You fi rst trained as a medical doctor… Yes. I wished primarily to study biology, but there was simply no hope because of the very limited number of places. So I studied medicine because I …