Journal: Nature Communications
Article Title: Engineering glycosyltransferases into glycan binding proteins using a mammalian surface display platform
doi: 10.1038/s41467-025-62018-z
Figure Lengend Snippet: a Fc-pST3Gal1 (PS1) has four structural motifs. Amino acids shown in cyan (Q108A, Y233A, and Y269F) and magenta (H302A) were mutated in Dead and H302A mutants, respectively. b pST3Gal1 co-crystalized with CMP and Galβ1,3GalNAcα- p NP (PDB: 2WNB). Protein is in green, with selected residues and ligands shown as sticks. CMP is orange, Galβ1,3GalNAcα- p NP is yellow, amino acids mutated in Dead mutant are cyan, and H302A is magenta. c Western blots of Fc-fusion proteins expressed using HEK293T cells under reducing and non-reducing conditions. Detection was performed using anti-human Fc specific IgG. d LC-MS/MS analysis of ST3Gal1 enzymatic activity. Recombinant hST3Gal1 served as positive control. H302A and dead mutants did not yield product (N = 1). e Lectin binding to HEK293T (gray bars), COLO357-FG (green bars) or Calu-3 (blue bars) cells, with or without sialidase treatment, measured using flow cytometry. Cells were incubated with 5 μg/mL fluorescent MALII, PNA, or 1 μg/mL purified Fc-fusion proteins pre-complexed with AF647-conjugated anti-human Fc specific IgG. Data are mean ± STD (N = 3 biological replicates). * p < 0.05 with respect to all other samples; ‡ p < 0.05 with respect to all other samples except samples marked by ‡ are not different from each other. P values calculated using one-way ANOVA followed by Tukey post-test. f Dose dependent binding of PS1 and H302A pre-complexed with AF488-conjugated anti-human Fc specific IgG. HEK293T cells treated with or without sialidase were used. Data are mean (N = 2 biological replicates). Source data including exact P values. Created in BioRender. Neelamegham, S. ( https://BioRender.com/tigz92o ).
Article Snippet: Recombinant human ST3Gal1 (rhST3Gal1, Product code: 6905-GT-020), Recombinant human P-selectin Fc chimera (P-selectin-Fc, Product code: 137-PS-050), sheep anti-hGCNT1 IgG (Product code: AF7248-SP) and HRP donkey anti-sheep H + L IgG (Product code: HAF016) were from R&D Systems (Minneapolis, MN).
Techniques: Mutagenesis, Western Blot, Liquid Chromatography with Mass Spectroscopy, Activity Assay, Recombinant, Positive Control, Binding Assay, Flow Cytometry, Incubation, Purification