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Molecular flip-flops formed by overlapping Fis sites.

ABSTRACT: The DNA-binding protein Fis frequently uses pairs of sites 7 or 11 base pairs (bp) apart. Two overlapping Fis sites separated by 11 bp are found in the Escherichia coli origin of chromosomal replication. Only one of these sites is bound by Fis at a time, so the structure is a molecular flip-flop that could direct alternative firing of replication complexes in opposite directions. Alternatively, the flip-flop could represent part of an on-off switch for replication. Because they can be used to create precise switched states, molecular flip-flops could be used as the basis of a novel molecular computer.

SUBMITTER: Hengen PN

PROVIDER: S-EPMC275571 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature

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Molecular flip-flops formed by overlapping Fis sites.

Hengen Paul N PN Lyakhov Ilya G IG Stewart Lisa E LE Schneider Thomas D TD

Nucleic acids research 20031101 22

The DNA-binding protein Fis frequently uses pairs of sites 7 or 11 base pairs (bp) apart. Two overlapping Fis sites separated by 11 bp are found in the Escherichia coli origin of chromosomal replication. Only one of these sites is bound by Fis at a time, so the structure is a molecular flip-flop that could direct alternative firing of replication complexes in opposite directions. Alternatively, the flip-flop could represent part of an on-off switch for replication. Because they can be used to cr ...[more]

PMID: 14602927

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