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Identification of site-specific recombination genes int and xis of the Rhizobium temperate phage 16-3.

ABSTRACT: Phage 16-3 is a temperate phage of Rhizobium meliloti 41 which integrates its genome with high efficiency into the host chromosome by site-specific recombination through DNA sequences of attB and attP. Here we report the identification of two phage-encoded genes required for recombinations at these sites: int (phage integration) and xis (prophage excision). We concluded that Int protein of phage 16-3 belongs to the integrase family of tyrosine recombinases. Despite similarities to the cognate systems of the lambdoid phages, the 16-3 int xis att system is not active in Escherichia coli, probably due to requirements for host factors that differ in Rhizobium meliloti and E. coli. The application of the 16-3 site-specific recombination system in biotechnology is discussed.

SUBMITTER: Semsey S

PROVIDER: S-EPMC93918 | biostudies-literature | 1999 Jul

REPOSITORIES: biostudies-literature

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Identification of site-specific recombination genes int and xis of the Rhizobium temperate phage 16-3.

Semsey S S Papp I I Buzas Z Z Patthy A A Orosz L L Papp P P PP

Journal of bacteriology 19990701 14

Phage 16-3 is a temperate phage of Rhizobium meliloti 41 which integrates its genome with high efficiency into the host chromosome by site-specific recombination through DNA sequences of attB and attP. Here we report the identification of two phage-encoded genes required for recombinations at these sites: int (phage integration) and xis (prophage excision). We concluded that Int protein of phage 16-3 belongs to the integrase family of tyrosine recombinases. Despite similarities to the cognate sy ...[more]

PMID: 10400574

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