Abstract:
:Site-specific recombination is responsible for a broad range of biological phenomena, including DNA inversion, resolution of transposition intermediates, and the integration and excision of bacteriophage genomes. Integration of mycobacteriophage L5 is catalyzed by a phage-encoded integrase with recombination occurring between specific attachment sites on the phage and mycobacterial chromosomes (attP and attB, respectively). Although some site-specific recombination systems simply involve binding of the recombinase to the sites of strand exchange, synapsis, and recombination, phage systems typically require the assembly of higher-order structures within which the recombinational potential of integrase is activated. The requirement for these structures derives from the necessity to regulate the directionality of recombination-either integration or excision-which must be closely coordinated with other aspects of the phage growth cycles. We show herein that there are multiple pathways available for the assembly of L5 recombination complexes, including the early synapsis of the attP and attB DNAs. This process is in contrast to the model for lambda integration and illustrates the different usage of molecular machineries to accomplish the same biological outcome.
journal_name
Proc Natl Acad Sci U S Aauthors
Peña CE,Kahlenberg JM,Hatfull GFdoi
10.1073/pnas.140014297keywords:
subject
Has Abstractpub_date
2000-07-05 00:00:00pages
7760-5issue
14eissn
0027-8424issn
1091-6490pii
140014297journal_volume
97pub_type
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