The integrase family of recombinase: organization and function of the active site.
The integrase family of site-specific recombinases (also called the tyrosine recombinases) mediate a wide range of biological outcomes by the sequential exchange of two pairs of DNA strands at defined phosphodiester positions. The reaction produces a recombinant arrangement of the DNA sequences flanking the cross-over region. The crystal structures of four integrase family members have revealed very similar three-dimensional protein folds that belie the large diversity in amino acid sequences among them. The active sites are similar in organization to those seen in structures of eukaryotic type IB topoisomerases, and conservation of catalytic mechanism is expected. The crystal structures, combined with previous biochemical knowledge, allow the refinement of models for recombination and the assignment of catalytic function to the active site residues. However, each system has its own peculiarities, and the exact sequence of events that allows the reaction to proceed from the first exchange reaction to the second is still unclear for at least some family members.
Grainge
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I
Department of Microbiology and The Institute of Cell and Molecular Biology, University of Texas at Austin, 78712, USA. grainge@mail.utexas.edu
Jayaram
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M
D001665:Binding Sites; D004254:DNA Nucleotidyltransferases / Q000737:chemistry*; D004264:DNA Topoisomerases, Type I / Q000737:chemistry; D006801:Humans; D019426:Integrases / Q000737:chemistry*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011487:Protein Conformation; D045522:Recombinases; D011995:Recombination, Genetic
D045522:Recombinases; D004254:DNA Nucleotidyltransferases; D019426:Integrases; C115006:integron integrase IntI1; D004264:DNA Topoisomerases, Type I