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Probing the structure of RecA-DNA filaments. Advantages of a fluorescent guanine analog.

ABSTRACT: The RecA protein of Escherichia coli plays a crucial roles in DNA recombination and repair, as well as various aspects of bacterial pathogenicity. The formation of a RecA-ATP-ssDNA complex initiates all RecA activities and yet a complete structural and mechanistic description of this filament has remained elusive. An analysis of RecA-DNA interactions was performed using fluorescently labeled oligonucleotides. A direct comparison was made between fluorescein and several fluorescent nucleosides. The fluorescent guanine analog 6-methylisoxanthopterin (6MI) demonstrated significant advantages over the other fluorophores and represents an important new tool for characterizing RecA-DNA interactions.

SUBMITTER: Singleton SF

PROVIDER: S-EPMC2031864 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature

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Probing the structure of RecA-DNA filaments. Advantages of a fluorescent guanine analog.

Singleton Scott F SF Roca Alberto I AI Lee Andrew M AM Xiao Jie J

Tetrahedron 20070401 17

The RecA protein of Escherichia coli plays a crucial roles in DNA recombination and repair, as well as various aspects of bacterial pathogenicity. The formation of a RecA-ATP-ssDNA complex initiates all RecA activities and yet a complete structural and mechanistic description of this filament has remained elusive. An analysis of RecA-DNA interactions was performed using fluorescently labeled oligonucleotides. A direct comparison was made between fluorescein and several fluorescent nucleosides. T ...[more]

PMID: 17955055

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Dynamics of RecA filaments on single-stranded DNA.

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