Architecture of a serine recombinase-DNA regulatory complex.
An essential feature of many site-specific recombination systems is their ability to regulate the direction and topology of recombination. Resolvases from the serine recombinase family assemble an interwound synaptic complex that harnesses negative supercoiling to drive the forward reaction and promote recombination between properly oriented sites. To better understand the interplay of catalytic and regulatory functions within these synaptic complexes, we have solved the structure of the regulatory site synapse in the Sin resolvase system. It reveals an unexpected synaptic interface between helix-turn-helix DNA-binding domains that is also highlighted in a screen for synapsis mutants. The tetramer defined by this interface provides the foundation for a robust model of the synaptic complex, assembled entirely from available crystal structures, that gives insight into how the catalytic activity of Sin and other serine recombinases may be regulated.
Mouw
Kent W
KW
Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
Rowland
Sally-J
SJ
Gajjar
Mark M
MM
Boocock
Martin R
MR
Stark
W Marshall
WM
Rice
Phoebe A
PA
D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D001665:Binding Sites; D002384:Catalysis; D003460:Crystallization; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry*; D004254:DNA Nucleotidyltransferases / Q000737:chemistry* / Q000235:genetics; D019281:Dimerization; D008958:Models, Molecular; D009154:Mutation; D011487:Protein Conformation; D011995:Recombination, Genetic
D001426:Bacterial Proteins; D004247:DNA; D004254:DNA Nucleotidyltransferases; C086893:sin protein, Staphylococcus aureus