Integration host factor binds to a unique class of complex repetitive extragenic DNA sequences in Escherichia coli.
Interspersed repeated DNA sequences are characteristic features of both prokaryotic and eukaryotic genomes. REP sequences are defined as conserved repetitive extragenic palindromic sequences and are found in Escherichia coli, Salmonella typhimurium and other closely related enteric bacteria. These REP sequences may participate in the folding of the bacterial chromosome. In this work we describe a unique class of 28 conserved complex REP clusters, about 100bp long, in which two inverted REPs are separated by a singular integration host factor (IHF) recognition sequence. We term these sequences RIP (for repetitive IHF-binding palindromic) elements and demonstrate that IHF binds to them specifically. It is estimated that there are about 70 RIP elements in E. coli. Our analysis shows that the RIP elements are evenly distributed around the bacterial chromosome. The possible function of the RIP element is discussed.
Department of Molecular Genetics, Hebrew University, Hadassah Medical School, Jerusalem, Israel.
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Oppenheim
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Rudd
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Mendelson
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D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D002876:Chromosomes, Bacterial; D016384:Consensus Sequence; D004269:DNA, Bacterial / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics*; D034982:Integration Host Factors; D008969:Molecular Sequence Data; D011485:Protein Binding; D012091:Repetitive Sequences, Nucleic Acid; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D034982:Integration Host Factors; C440508:integration host factor, Salmonella