Key points are not available for this paper at this time.
Purified recA protein, product of the recA+ gene, promotes homologous pairing between intact covalent circular duplex DNA and circular single-stranded DNA carrying a short hybridized fragment West, S. C., Cassuto, E. & Howard-Flanders, P. (1981) Nature (London) 290, 29-33.. In this paper we investigate the interaction of duplex fragments with circular single-stranded DNA carrying the hybridized fragment and find that recA protein promotes an efficient strand-exchange reaction between interacting DNA molecules. The exchange is dependent upon linear duplex DNA fragments that are homologous to, but extend beyond, the short fragment present on the hybridized DNA substrate. The reactions require stoichiometric amounts of recA protein and the presence of ATP.
West et al. (Wed,) studied this question.