We describe a fast and very efficient method of purification which yields highly purified integration host factor-like proteins in one chromatografie step. IHF-like proteins from Acinetobacter junii or Proteus vulgaris are each an a£ heterodimer (subunits of 10 and 11 kDa) similar to the IHF of Escherichia coli when analyzed by polyacrylamide gel electrophoresis. The purified IHF are able to bind to the same ihf sites as IHF of E. coli. The results presented confirm that IHF is conserved during evolution in gram-negative bacteria.
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