Figure 8

Sequence alignment of the αI ₂ helix and the β-4,5 strands region of some integron integrases (IntIs). IntI2*, class 2 IntI from Tn7; SonIntIA, IntI from Shewanella oneidensis MR1; VchIntIA, IntI from the Vibrio cholerae chromosomal integron; IntI1, class 1 IntI from plasmid pVS1; IntI3, class 3 IntI from a S. marcescens plasmid. Residues potentially related to the difference in specificity of IntI2 and SonIntIA versus IntI1 and IntI3 are identified by arrows. Positions of the αI₂ helix and the β-4,5 strands in this figure are based on the VchIntIA structure (Protein Data Bank accession no. 2A3V) [29].