Multiple sequence alignment of members of human galectins. All the 12 known human galectins (Gal) are grouped on subtypes of prototypes: galectin-1 (UniProt code: P09382), galectin-2 (P05162), galectin-7 (P47929), galectin-10 (Q05315), galectin-13 (Q9UHV8), galectin-14 (Q8TCE9-1) and galectin-16 (A8MUM7); chimera type: galectin-3 (P17931) and tandem-repeat type: galectin-4 (P56470), galectin-8 (O00214-1), galectin-9 (O00182-1) and galectin-12 (Q96DT0-1). All tryptophan residues are coloured in red. Below the galectin sequence alignment is a key denoting conserved amino acid residues (*), conservative substitutions (:) and semi-conservative substitutions (.) within the Carbohydrate Recognition Domains (CRDs). The ubiquitous tryptophan residues in N- and C-terminal CRDs of all the galectin members are highlighted in blue brackets.