biostudies-literatureMacDonald AIBiotechnology and Biological Sciences Research CouncilNational Science Foundation26280https://www.ebi.ac.uk/biostudies/studies/S-EPMC11530663biostudies-literatureUnknown14(1)Serine integrases are phage- (or mobile element-) encoded enzymes that catalyse site-specific recombination reactions between a short DNA sequence on the phage genome (attP) and a corresponding host genome sequence (attB), thereby integrating the phage DNA into the host genome. Each integrase has its unique pair of attP and attB sites, a feature that allows them to be used as orthogonal tools for genome modification applications. In the presence of a second protein, the Recombination Directionality Factor (RDF), integrase catalyses the reverse excisive reaction, generating new recombination sites, attR and attL. In addition to promoting attR x attL reaction, the RDF inhibits attP x attB recombination. This feature makes the directionality of integrase reactions programmable, allowing them Scientific reportsVariable orthogonality of serine integrase interactions within the ϕC31 family.PMC11530663BB/003356/1BB/X012085/12223480MacDonald AIRice PAOlorunniji FJBaksh AHolland AShin HStark WMfalseVariable orthogonality of serine integrase interactions within the ϕC31 family.Serine integrases are phage- (or mobile element-) encoded enzymes that catalyse site-specific recombination reactions between a short DNA sequence on the phage genome (attP) and a corresponding host genome sequence (attB), thereby integrating the phage DNA into the host genome. Each integrase has its unique pair of attP and attB sites, a feature that allows them to be used as orthogonal tools for genome modification applications. In the presence of a second protein, the Recombination Directionality Factor (RDF), integrase catalyses the reverse excisive reaction, generating new recombination sites, attR and attL. In addition to promoting attR x attL reaction, the RDF inhibits attP x attB recombination. This feature makes the directionality of integrase reactions programmable, allowing them 2024-01-01T00:00:00Z2024 Nov2026-06-02T04:01:35.488Z2025-04-06T23:17:45.403ZS-EPMC115306633948729110.1038/s41598-024-77570-9