Branching Out In Different Ways

Abstract

An important tool has been missing from the carbohydrate chemist’s toolbox: the ability to easily synthesize libraries of asymmetrically branched N-linked glycans. Without this tool, chemists haven’t been able to use these common molecules—often attached to proteins on cell surfaces—to screen drug candidates and explore ways cells communicate. Now, a strategy developed by Geert-Jan Boons and coworkers at the Complex Carbohydrate Research Center at the University of Georgia changes that. The work could be useful for making carbohydrate arrays for drug discovery and for studying how cell-surface glycans control cell signaling and other biological processes. Unlike nucleic acids and proteins, glycans aren’t made by copying a template but instead are assembled in a customized way by enzymes. And most glycans have highly variable branched structures, which are constructed from sugars. All of that means glycans are hard to synthesize. Chemical synthesis has taken a lot of time, and enzymatic methods ...