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Function and horizontal transfer of the small terminase subunit of the tailed bacteriophage Sf6 DNA packaging nanomotor.

ABSTRACT: Bacteriophage Sf6 DNA packaging series initiate at many locations across a 2kbp region. Our in vivo studies show that Sf6 small terminase subunit (TerS) protein recognizes a specific packaging (pac) site near the center of this region, that this site lies within the portion of the Sf6 gene that encodes the DNA-binding domain of TerS protein, that this domain of the TerS protein is responsible for the imprecision in Sf6 packaging initiation, and that the DNA-binding domain of TerS must be covalently attached to the domain that interacts with the rest of the packaging motor. The TerS DNA-binding domain is self-contained in that it apparently does not interact closely with the rest of the motor and it binds to a recognition site that lies within the DNA that encodes the domain. This arrangement has allowed the horizontal exchange of terS genes among phages to be very successful.

SUBMITTER: Leavitt JC

PROVIDER: S-EPMC3643300 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Function and horizontal transfer of the small terminase subunit of the tailed bacteriophage Sf6 DNA packaging nanomotor.

Leavitt Justin C JC Gilcrease Eddie B EB Wilson Kassandra K Casjens Sherwood R SR

Virology 20130404 2

Bacteriophage Sf6 DNA packaging series initiate at many locations across a 2kbp region. Our in vivo studies show that Sf6 small terminase subunit (TerS) protein recognizes a specific packaging (pac) site near the center of this region, that this site lies within the portion of the Sf6 gene that encodes the DNA-binding domain of TerS protein, that this domain of the TerS protein is responsible for the imprecision in Sf6 packaging initiation, and that the DNA-binding domain of TerS must be covalen ...[more]

PMID: 23562538

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