These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Cleavage of phi X174 single-stranded DNA by gene A protein and formation of a tight protein-DNA complex.
    Author: Eisenberg S.
    Journal: J Virol; 1980 Aug; 35(2):409-13. PubMed ID: 6449606.
    Abstract:
    The gene A protein cleaves phi X174 single-stranded DNA (ssDNA). The cleavage appears to be stoichiometric, whereby a gene A protein molecule breaks a phosphodiester bond and binds to the 5' end. The enzyme introduces mostly a single break in a circular ssDNA molecule. However, at high enzyme-to-DNA ratios, more than one break in the DNA could be observed. The cleavage of the ssDNA by gene A protein renders the DNA sensitive to the action of terminal transferase to incorporate [alpha -32P]ATP. Thus, the 3'OH end is free. All attempts to label the 5' end by T4-induced polynucleotide kinase and [gamma-32P]ATP failed. The formation of a gene A-ssDNA complex was demonstrated directly by using 3H-labeled gene A protein and 32P-labeled ssDNA in the reaction. Such a complex is resistant to treatments with 0.2 M NaOH, banding in CsCl, and boiling in 2.5% sodium dodecyl sulfate. Only treatment with a nuclease released the bound protein. Also, after cleaving [32P]ssDNA by gene A protein, followed by either DNase I or micrococcal nuclease digestion, a fraction of the 32P label remained resistant to nuclease treatment and comigrated with gene A protein on polyacrylamide gels.
    [Abstract] [Full Text] [Related] [New Search]