Overexpression of PtxtPL1-27 affects extractability of many polymers of wood. Sequential cell wall extracts, obtained using α-amylase, endo-polygalacturonase (EPG)/ pectin methylesterase (PME), sodium carbonate, 1 M potassium hydroxide (KOH) and 4 M KOH, were probed with a panel of 150 monoclonal antibodies (A-C) and analyzed for the monosaccharide composition (D). (A-C) Extracts were screened against an array of plant glycan-directed monoclonal antibodies using ELISA. (A) Antibody binding (average of two biological replicates) is depicted as colored heat maps; bright yellow, maximal binding; black, no binding. The colored panel (right) depicts groups of antibodies used, identified according to polysaccharides predominantly recognized by each group  (list of antibodies provided in Additional file 5). Colored boxes indicate regions of the glycome profiles that were altered in both transgenic lines (blue boxes) or predominantly in one line (orange boxes) compared to wild-type (WT). (B) Signals ≥0.1 from pectin- and arabinogalactan (AG)-directed antibodies recognizing epitopes in α-amylase and EPG/PME extracts. (C) Signals ≥0.1 from an expanded set of xylan-directed antibodies specifically recognizing epitopes in aspen wood hemicelluloses in 1 M KOH and 4 M KOH extracts. (D) Monosaccharide composition of sequential extracts. Only monosaccharides that differed in content in extracts between PtxtPL1-27 overexpressing lines and the WT are presented (full dataset in Additional file 6). Data in B-D are means of two biological replicates ± standard error. Asterisks indicate probability for significance of difference between transgenic lines and WT (post analysis-of-variance contrast: *P ≤10%, **P ≤5%, ***P ≤1%, ****P ≤0.1%).