Fig. 2

Sequence alignment of FADS1 and FADS2 amino acid sequences. Orange boxes correspond to the conserved histidine boxes, the yellow box indicates residues proposed to be involved in substrate specificity [27], and blue boxes indicate residues replaced in rat FADS2 Δ6 desaturase to obtain Δ5 activity [27]. The heme binding motif HPGG is also shown