Method uses core carbohydrate to build variations of ubiquitous but enigmatic biomolecules Scientists have demonstrated a new method for synthesizing glycans, a class of crucial but elusive carbohydrates. The technique opens the way to a comprehensive study of glycans, one of four key macromolecule groups in biology — along with proteins, nucleic acids and lipids — and the least studied of them. The results could also lead to a better understanding of the outer shells of viruses. Glycans are made of sugar molecules, which can form simple chains or more elaborate, branching arrangements. They are ubiquitous in the living world....