CBM_26 is a family of bacterial carbohydrate-binding modules frequently found at the C-terminus of enzymes. The combination is not unusual as the CBMs function to bring the relevant polysaccharide into close proximity to the active site [1].

1: Structural and functional characterization of Pseudomonas aeruginosa AlgX: role of AlgX in alginate acetylation. Riley LM, Weadge JT, Baker P, Robinson H, Codee JD, Tipton PA, Ohman DE, Howell PL; J Biol Chem. 2013;288:22299-22314. PMID:23779107