E. coli recA protein possesses a strand separating activity on short duplex DNAs.
RecA protein was found to catalyze the dissociation of the strands of a DNA substrate consisting of a 20-nucleotide primer annealed to circular single-stranded M13mp DNA. The strand separation reaction requires ATP hydrolysis and the presence of single-stranded DNA flanking the duplex DNA region to be unwound. RecA-catalyzed strand separation is effective only for very short duplexes, not exceeding 30 bp, and is not stimulated by single-stranded DNA-binding protein. These results are consistent with the ability of recA protein to disrupt regions of secondary structure in single-stranded DNA and to incorporate large non-homologies into heteroduplex DNA.
D004247:DNA / Q000302:isolation & purification / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D009692:Nucleic Acid Heteroduplexes / Q000378:metabolism; D010957:Plasmids; D011938:Rec A Recombinases / Q000378:metabolism*; D013329:Structure-Activity Relationship
D009692:Nucleic Acid Heteroduplexes; D004247:DNA; D011938:Rec A Recombinases