Nature 517, 165–169 (2015); doi:10.1038/nature13995

In this Article focusing on the selfish metabolism of yeast mannan by Bacteroidetes, we also described a polysaccharide utilization locus (PUL) responsible for the degradation of high mannose mammalian N-glycan (HMNG) but omitted to cite two relevant papers1,2, for which we apologise. Both studies describe a model for the degradation of complex biantennary N-glycans by Bacteroidetes in which the degradative enzymes are encoded by PULs. These studies1,2 provide examples of how PULs can orchestrate N-glycan metabolism in addition to the HMNG PUL we describe in this Article. In all three papers it is proposed that N-glycan depolymerization occurs primarily in the periplasm.