Fig. 1: Functional reconstitution of oligomannose synthesis.
From: Structures of ALG3/9/12 reveal the assembly logic of the N-glycan oligomannose core
a, Schematic of N-glycan synthesis in the human ER. b, Strategy for the chemoenzymatic synthesis of the substrates for the luminal ER mannosyltransferases. Structures of the chemically synthesized starting compounds, Dol25-PP-GlcNAc2 and Dol25-P-Man, are shown. The obtained glycans were transferred to a fluorescent peptide using TbSTT3B and separated on a tricine gel. Structures above the gel lanes are indicated according to the Symbol Nomenclature for Glycans. c–f, Time courses of enzymatic activity using WT ScALG3 and Dol25-PP-GlcNAc2Man5 (c), WT HsALG9 and Dol25-PP-GlcNAc2Man6 (d), WT GgALG12 and Dol25-PP-GlcNAc2Man7 (e) and WT HsALG9 and Dol25-PP-GlcNAc2Man8 (f). Incubation times were as indicated. Lanes with glycopeptide cartoons over them serve as glycopeptide standards for the indicated glycan. Activity assays in b –f were performed at least twice for each enzyme–substrate combination with similar results.
