Fig. 2. Hybrid integrases: architectures and naming.

(A) Domain organization of parental and chimeric integrases. Pairwise phiBT1-phiC31 and TG1-phiC31 integrase domain alignments were performed, and the percent similarity is shown between the respective regions. EMBOSS Needle with the BLOSUM62 scoring matrix was used for all sequence alignments (Rice et al., 2000). The architectures of two representative hybrids are displayed below the parental enzymes. All chimeric integrases described in this study have been assigned systematic names that specify the parental proteins and fusion indices used to create them. (B) Detailed view of the relative indexing scheme that we developed to specify protein fusions. See the text for an explanation of our naming system.