GSBS Student Publications


Allosteric regulation of RecA protein function is mediated by Gln194

GSBS Program

Biochemistry & Molecular Pharmacology

UMMS Affiliation

Graduate School of Biomedical Sciences; Department of Biochemistry and Molecular Pharmacology



Document Type


Medical Subject Headings

Adenosine Triphosphatases; Adenosine Triphosphate; Allosteric Regulation; Binding Sites; DNA, Single-Stranded; Glutamine; Hydrolysis; Models, Molecular; Mutagenesis, Site-Directed; Rec A Recombinases; Structure-Activity Relationship


Life Sciences | Medicine and Health Sciences


Binding of ATP to the RecA protein induces a high affinity DNA binding required for activation of enzyme function. Screens for in vivo recombination and repressor cleavage activities show Gln194 to be intolerant of all substitutions. Analyses of three mutant proteins (Q194N, Q194E, and Q194A) show that although basal enzyme function is maintained, each protein no longer displays an ATP-induced increase in DNA binding affinity. High salt activation of RecA function is also disrupted by these mutations. In contrast, ATP-induced changes in the oligomeric structure of RecA are maintained in the mutant proteins. These results demonstrate that Gln194 is a critical "allosteric switch" for ATP-induced activation of RecA function but is not the exclusive mediator of ATP-induced changes in RecA.

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Citation: J Biol Chem. 1997 Oct 10;272(41):25778-82.

Related Resources

Link to article in PubMed

Journal Title

The Journal of biological chemistry

PubMed ID