Thermochemical and kinetic evidence for nucleotide-sequence-dependent RecA-DNA interactions
Artikel i vetenskaplig tidskrift, 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.

fluorescence

recombination

calorimetry

RecA

protein-DNA interaction

Författare

Pernilla Wittung Stafshede

Institutionen för fysikalisk kemi

C. Ellouze

F. Maraboeuf

M. Takahashi

Bengt Nordén

Institutionen för fysikalisk kemi

European Journal of Biochemistry

0014-2956 (ISSN)

Vol. 245 715-719

Styrkeområden

Nanovetenskap och nanoteknik

Energi

Livsvetenskaper och teknik

Materialvetenskap

Ämneskategorier

Fysikalisk kemi

Fundament

Grundläggande vetenskaper

DOI

10.1111/j.1432-1033.1997.00715.x