Direct atomic force microscopy visualization of integration host factor-induced DNA bending structure of the promoter regulatory region on the Pseudomonas TOL plasmid.

Gi Hun Seong; Eiry Kobatake; Koshiro Miura; Atsushi Nakazawa; Masuo Aizawa

doi:10.1006/bbrc.2002.6443

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Direct atomic force microscopy visualization of integration host factor-induced DNA bending structure of the promoter regulatory region on the Pseudomonas TOL plasmid.

Gi Hun Seong·Eiry Kobatake·Koshiro Miura·Atsushi Nakazawa·Masuo Aizawa

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Abstract

Atomic force microscopy (AFM) was used to analyze DNA bending induced by integration host factor (IHF). The direct AFM visualization of IHF-DNA complexes on the OP1 promoter regulatory regions on the Pseudomonas TOL plasmid showed that there was no intrinsic DNA bend in the OP1 promoter region, but a sharp DNA bend was induced by binding of IHF to the region between the upstream regulatory sequence and the promoter sequence. The DNA bending angles were distributed with a mean bend angle of 123 degrees. The IHF-DNA complexes were shown to bend at the IHF binding site giving rise to an asymmetric structure. These results provide direct evidence that IHF is required functionally for activation of OP1 transcription and support the DNA-loop model that the sharp DNA bend induced by binding of IHF facilitates the contact between RNA polymerase bound by the promoter sequence and XylR protein attached to the upstream sequence in the OP1 promoter.

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Bacterial Proteins Binding Sites DNA, Bacterial DNA-Binding Proteins Integration Host Factors Macromolecular Substances Microscopy, Atomic Force Nucleic Acid Conformation Plasmids Promoter Regions, Genetic Pseudomonas Regulatory Sequences, Nucleic Acid Journal Article

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Gi Hun Seong, Eiry Kobatake, Koshiro Miura, Atsushi Nakazawa, Masuo Aizawa. 2002-02-22. Direct atomic force microscopy visualization of integration host factor-induced DNA bending structure of the promoter regulatory region on the Pseudomonas TOL plasmid.. https://doi.org/10.1006/bbrc.2002.6443

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