Multiple sequence alignment of protein sequences identified in a cDNA library of unfed/2 d fed or 6 d fed D. variabilis midguts (DvM) and published tick GST sequences found on genbank. Catalytic residues are indicated by an asterisk and conserved residues involved in the GST fold are indicated by arrowheads. The conserved SMAIL domain is boxed. Shading represents 100% identity (black) or similarity (grey) among the sequences. Alignments were conducted using CLUSTALX. D. variabilis (Dv), Ixodes pacificus (Ip), Rhipicephalus appendiculatus (Ra), R. (Boophilus) microplus (Bm), and Haemaphysalis longicornis (Hl).