title: Stoichiometry of DNA binding by the bacteriophage SP01-encoded type II DNA-binding protein TF1.
abstract: The stoichiometry of DNA binding by the bacteriophage SP01-encoded type II DNA-binding protein TF1 has been determined. 3H-Labeled TF1 was allowed to bind to a 32P-labeled DNA fragment containing a TF1 binding site. Multiple TF1-DNA complexes were resolved from each other and from unbound DNA by native gel electrophoresis. DNA-protein complexes were cut from polyacrylamide gels, and the amounts of 3H and 32P contained in each slice were measured. A ratio of 1.12 +/- 0.06 TF1 dimer/DNA molecule was calculated for the fastest-migrating TF1-DNA complex. We conclude that TF1 has a DNA-binding unit of one dimer. More slowly migrating complexes are apparently formed by serial addition of single TF1 dimers.
authors.affiliation: Department of Biology, University of California, San Diego, La Jolla 92093.
authors.forename: G J
authors.initials: GJ
authors.lastname: Schneider
authors.forename: E P
authors.initials: EP
authors.lastname: Geiduschek
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001435:Bacteriophages / Q000235:genetics* / Q000378:metabolism; D002850:Chromatography, Gel; D004279:DNA, Viral / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics*; D007700:Kinetics; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D011994:Recombinant Proteins; C040330:histone-like protein HU, bacteria