Thermochemical and kinetic evidence for nucleotide-sequence-dependent RecA-DNA interactions
Journal article, 1997

RecA catalyses homologous recombination in Escherichia coli by promoting pairing of homologous DNA molecules after formation of a helical nucleoprotein filament with single-stranded DNA. The primary reaction of RecA with DNA is generally assumed to be unspecific. We show here, by direct measurement of the interaction enthalpy by means of isothermal titration calorimetry, that the polymerisation of RecA on single-stranded DNA depends on the DNA sequence, with a high exothermic preference for thymine bases. This enthalpic sequence preference of thymines by RecA correlates with faster binding kinetics of RecA to thymine DNA. Furthermore, the enthalpy of interaction between the RecA.DNA filament and a second DNA strand is large only when the added DNA is complementary to the bound DNA in RecA. This result suggests a possibility for a rapid search mechanism by RecA.DNA filaments for homologous DNA molecules.

protein-DNA interaction






Pernilla Wittung

Department of Physical Chemistry

C. Ellouze

F. Maraboeuf

M. Takahashi

Bengt Nordén

Department of Physical Chemistry

European Journal of Biochemistry

0014-2956 (ISSN)

Vol. 245 3 715-719

Areas of Advance

Nanoscience and Nanotechnology


Life Science Engineering (2010-2018)

Materials Science

Subject Categories

Physical Chemistry


Basic sciences



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