Single strands induce recA protein to unwind duplex DNA for homologous pairing

Abstract
Single-stranded DNA, whether homologous or not, stimulates purified Escherichia coli recA protein to unwind duplex DNA. This helps to explain how recA promotes a search for homology in genetic recombination. As oligodeoxynucleotides also stimulate unwinding, a common mechanism may relate the function of recA protein in recombination to other functions (SOS) induced by oligonucleotides.