Figure 2

Multiple sequence alignment of Gg NEU3 with other vertebrate membrane-bound sialidases and Hs NEU2. Multiple alignment of the amino acid sequence of chicken NEU3 (Gg NEU3, GQ365760) with human sialidase NEU2 (Hs NEU2, NP_005374) and NEU3 from human (Hs NEU3, NP_006647), mouse (Mm NEU3, NP_057929), opossum (Md NEU3, XP_001366978), zebra finch (Tg NEU3, XP_002187487) and turkey (Mg NEU3, GU828006) performed with ClustalW2. Putative residues involved in the active site formation are indicated by *; (Y/F)RIP motif and Asp-boxes are framed with gray and black lines, respectively. The expanded region containing the repeats in chicken and turkey NEU3 is indicated with gray double arrows below the alignment, each one representing one of the 7 repeated units. The black bar indicates the region deleted in Gg NEU3-Del mutated protein. The 6 colored arrows above the alignment indicate the blades that compose the predicted Gg NEU3 β-propeller. The same color code is used in the 3D model in Figure 4.