Fig. 1.

Schematic illustration of O-acetylated galactoglucomannan and enzymes involved in degradation of the backbone (a) and released oligosaccharides (b). Sugars shown using the Consortium for Functional Glycomics notation [48]. The figure shows general glycoside linkage specificity of each type of enzyme and a given enzyme may be restricted by neighbouring backbone sugar monomers and/or substitutions, exemplified by the varying influence of galactosyl substituents and potentially backbone glucosyl units on mannanase activity [17, 26]. Dual linkage specificity is known to occur among some of the illustrated enzymes. As example, some endo-β(1→4)-glucanases may hydrolyse within the glucomannan backbones, either by action on the glucopyranosyl units or by being unspecific, i.e., hydrolysing at mannopyranosyl units [16]