Extended Data Fig. 3: Regioselectivity of the modification of pVIII protein.
From: Genetically encoded multivalent liquid glycan array displayed on M13 bacteriophage
a, Scheme of acid induced cleavage of Asp-5-Pro-6 (D5-P6)1 bond in pVIII to yield pVIII[1–5] and pVIII[6–55] fragments. b, Scheme of the modification of the phage clone with the azido-glycan Galf4 (Galfβ1-5Galfβ1-5Galfβ1-5Galfβ-(CH2)-N3). Modified phage was purified by Zeba column to remove unreacted glycan. c, MALDI-TOF analysis of modified and unmodified phage clones after incubation in 70% (v/v) TFA for 1 h (‘High TFA’) or without any pre-treatment with TFA (‘Low TFA’). Analysis detects unmodified pVIII[6–55] fragment but does not detect presence of glycosylated pVIII[6–55] fragment. Glycosylation, thus, occurs preferentially at the N-terminus residue. d, Scheme of the cleavage of the pVIII modified with the azido-glycan Galf4 on the N-terminus and ε-amine of Lys-8 residue. 1. Crimmins, D.L., Mische, S.M. & Denslow, N.D. Chemical cleavage of proteins in solution. Curr. Protoc. Protein Sci. 11(2005).
