Figure 4.
A plausible model for recombination directionality factor (RDF)-stimulated excision. The RDFs (yellow) could bind to the Int CC motifs and disrupt the intra-molecular interactions responsible for inhibiting attL x attR recombination. The RDFs may also interact with additional integrase domains and in some systems may interact with one another. Integrase domains are colored as in Fig. 1.