期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1981
卷号:78
期号:10
页码:6149-6153
DOI:10.1073/pnas.78.10.6149
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Purified recA protein promotes strand exchanges between linear duplex DNA and homologous circular single-stranded phage phi X174 DNA that carries a short hybridized fragment [West, S. C., Cassuto, E. & Howard-Flanders, P. (1981) Proc. Natl. Acad. Sci. USA 78, 2100-2104]. In this paper we investigate the mechanism of this strand exchange reaction. We show that recA protein initiates strand exchanges by pairing the free end of the duplex fragment with the single-stranded DNA. In addition, we find that strand exchanges are polar, stable heteroduplex molecules being formed by the directional transfer transfer of the (-) strands starting at 3' termini.