Interaction of a folded chromosome-associated protein with single-stranded DNA-binding protein of Escherichia coli, identified by affinity chromatography.
A single-stranded DNA-binding protein (SSB) affinity column was prepared by optimizing the coupling of Escherichia coli single-stranded DNA-binding protein to Affi-Gel 10. The bound SSB retained its ability to specifically bind single-stranded DNA. When nuclease-treated cell extracts were incubated with the SSB beads overnight at 4 degrees C, a major protein of Mr = 25,000 was bound. At shorter incubation times, two additional proteins of Mr = 32,000 and 36,000 were also detected. In the absence of nuclease treatment, eight additional proteins ranging from Mr = 14,000 to 160,000 also bound to the affinity column. The major Mr = 25,000 protein has been shown to be a folded chromosome-associated protein. Its binding to SSB is strongly enhanced by the addition of DNA polymerase III or DNA polymerase III holoenzyme.
D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002846:Chromatography, Affinity; D002875:Chromosomes / Q000032:analysis*; D004258:DNA Polymerase III / Q000378:metabolism / Q000494:pharmacology; D004269:DNA, Bacterial / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000032:analysis*; D007526:Isoelectric Point; D007700:Kinetics; D008970:Molecular Weight; D011485:Protein Binding; D013696:Temperature
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D004258:DNA Polymerase III