Integrase Class Site‐specific Recombinases


The integrase family of recombination proteins promote coordinated conservative DNA breakage–rejoining reactions at duplex DNA sites of defined sequence. They ensure accurate partition of duplicated circular prokaryotic chromosomes or insert and remove temperate phage genomes from host chromosomes through formation of a DNA–integrase phosphodiester linkage between a tyrosyl residue and a 3′‐phosphoryl group.

Keywords: tyrosine recombinases; mobile genetic elements; bacteriophage; covalent catalysis; topoisomerases

Figure 1.

Site‐specific recombination by integrases proceeds via a four‐stranded Holliday intermediate. The strands are coloured for clarity. The sites at which reactions occur are shown as blue blocks.



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Further Reading

Bayley CC, Morgan M, Dale EC and Ow DW (1992) Exchange of gene activity in transgenic plants catalyzed by the Cre‐lox site‐specific recombination system. Plant Molecular Biology 18: 353–361.

Craig NL (1988) The mechanism of conservative site‐specific recombination. Annual Review of Genetics 22: 77–105.

Grindley NDF (1997) Site‐specific recombination: Synapsis and strand exchange revealed. Current Biology 7: R608–R612.

Hall RM and Collis CM (1995) Mobile gene cassettes and integrons: capture and spread of genes by site‐specific recombination. Molecular Microbiology 15: 593–600.

Landy A (1989) Dynamic, structural, and regulatory aspects of lambda site‐specific recombination. Annual Review of Biochemistry 58: 913–949.

Landy A (1993) Mechanistic and structural complexity in the site‐specific recombination pathways of Int and FLP. Current Opinion in Genetics and Development 3: 699–707.

Sadowski PD (1995) The Flp recombinase of the 2‐microns plasmid of Saccharomyces cerevisiae. Progress in Nucleic Acid Research and Molecular Biology 51: 53–91.

Sherratt DJ, Arciszewska LK, Blakely G et al. (1995) Site‐specific recombination and circular chromosome segregation. Philosophical Transactions of the Royal Society of London, Series B (Biological Sciences) 347: 37–42.

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How to Cite close
Scocca, John J(Apr 2001) Integrase Class Site‐specific Recombinases. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0001059]