Gated rotation mechanism of site-specific recombination by ΦC31 integrase

Integrases, such as that of the Streptomyces temperate bacteriophage ΦC31, promote site-specific recombination between DNA sequences in the bacteriophage and bacterial genomes to integrate or excise the phage DNA. ΦC31 integrase belongs to the serine recombinase family, a large group of structurally...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2012-11, Vol.109 (48), p.19661-19666
Main Authors: Olorunniji, Femi J., Buck, Dorothy E., Colloms, Sean D., McEwan, Andrew R., Smith, Margaret C. M., Stark, W. Marshall, Rosser, Susan J.
Format: Article
Language:English
Subjects:
Bacteriophages
Bacteriophages - enzymology
Bacteriophages - genetics
Biological Sciences
catalytic activity
Catenanes
DNA
DNA damage
DNA, Viral - genetics
enzymes
Gels
genome
Hybridity
hybrids
Integrases - genetics
Integrases - metabolism
Ligation
nucleotide sequences
Plasmids
Recombination, Genetic
Rotation
serine
site-specific recombination
Synapses
Topology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Integrases, such as that of the Streptomyces temperate bacteriophage ΦC31, promote site-specific recombination between DNA sequences in the bacteriophage and bacterial genomes to integrate or excise the phage DNA. ΦC31 integrase belongs to the serine recombinase family, a large group of structurally related enzymes with diverse biological functions. It has been proposed that serine integrases use a "subunit rotation" mechanism to exchange DNA strands after double-strand DNA cleavage at the two recombining ait sites, and that many rounds of subunit rotation can occur before the strands are religated. We have analyzed the mechanism of ΦC31 integrase-mediated recombination in a topologically constrained experimental system using hybrid "phes" recombination sites, each of which comprises a ΦC31 att site positioned adjacent to a regulatory sequence recognized by Tn3 resolvase. The topologies of reaction products from circular substrates containing two phes sites support a right-handed subunit rotation mechanism for catalysis of both integrative and excisive recombination. Strand exchange usually terminates after a single round of 180° rotation. However, multiple processive "360° rotation" rounds of strand exchange can be observed, if the recombining sites have nonidentical base pairs at their centers. We propose that a regulatory "gating" mechanism normally blocks multiple rounds of strand exchange and triggers product release after a single round.
ISSN:0027-8424
1091-6490
DOI:10.1073/pnas.1210964109