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DNA arms do the legwork to ensure the directionality of lambda site-specific recombination.

ABSTRACT: The integrase protein of bacteriophage lambda (Int) catalyzes site-specific recombination between lambda phage and Escherichia coli genomes. Int is a tyrosine recombinase that binds to DNA core sites via a C-terminal catalytic domain and to a collection of arm DNA sites, distant from the site of recombination, via its N-terminal domain. The arm sites, in conjunction with accessory DNA-bending proteins, provide a means of regulating the efficiency and directionality of Int-catalyzed recombination. Recent crystal structures of lambda Int tetramers bound to synaptic and Holliday junction intermediates, together with new biochemical data, suggest a mechanism for the allosteric control of the recombination reaction through arm DNA binding interactions.

SUBMITTER: Radman-Livaja M

PROVIDER: S-EPMC1892226 | biostudies-literature | 2006 Feb

REPOSITORIES: biostudies-literature

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DNA arms do the legwork to ensure the directionality of lambda site-specific recombination.

Radman-Livaja Marta M Biswas Tapan T Ellenberger Tom T Landy Arthur A Aihara Hideki H

Current opinion in structural biology 20051220 1

The integrase protein of bacteriophage lambda (Int) catalyzes site-specific recombination between lambda phage and Escherichia coli genomes. Int is a tyrosine recombinase that binds to DNA core sites via a C-terminal catalytic domain and to a collection of arm DNA sites, distant from the site of recombination, via its N-terminal domain. The arm sites, in conjunction with accessory DNA-bending proteins, provide a means of regulating the efficiency and directionality of Int-catalyzed recombination ...[more]

PMID: 16368232

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