Stabilization of bacteriophage Mu repressor-operator complexes by the Escherichia coli integration host factor protein.
All of the previously described effects of integration host factor (IHF) on bacteriophage Mu development have supported the view that IHF favours transposition-replication over the alternative state of lysogenic phage growth. In this report we show that, consistent with a model in which Mu repressor binding to its operators requires a particular topology of the operator DNA, IHF stimulates repressor binding to the O1 and O2 operators and enhances Mu repression. IHF would thus be one of the keys, besides supercoiling and the H-NS protein, that lock the operator region into the appropriate topological conformation for high-affinity binding not only of the phage transposase but also of the phage repressor.
Gama
M J
MJ
Unité Transposition Bactérienne, Université Libre de Bruxelles, Rhode Saint Genèse, Belgium.
Toussaint
A
A
Higgins
N P
NP
D001426:Bacterial Proteins / Q000378:metabolism*; D010583:Bacteriophage mu / Q000378:metabolism*; D001483:Base Sequence; D004279:DNA, Viral / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004926:Escherichia coli; D034982:Integration Host Factors; D008969:Molecular Sequence Data; D009875:Operator Regions, Genetic / Q000502:physiology*; D012097:Repressor Proteins / Q000378:metabolism*; D013696:Temperature; D014764:Viral Proteins / Q000378:metabolism
D001426:Bacterial Proteins; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D034982:Integration Host Factors; D012097:Repressor Proteins; D014764:Viral Proteins