EFFECTS OF NONHOMOLOGY ON BACTERIOPHAGE LAMBDA RECOMBINATION

Michael Lichten ¹ and Maurice S. Fox ¹

¹ Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

When crosses are performed under conditions severely restricting DNA synthesis, the presence of DNA sequence nonhomologies in the lac region of plac5 limits the parental material contribution to and the yield of phage recombinant in a region bracketed by the nonhomologies. These observations are consistent with the expectation of a role for branch migration in the formation of heteroduplex structures under these conditions. Under conditions permissive for DNA replication, bracketing a region with nonhomologies has an only modest effect on the yield of recombinants within that interval. In addition, recombinants within such a bracketed interval manifest an excess of coincident exchange events in an adjacent region. These observations suggest the possibility that, under conditions permissive for DNA replication, regions of nonhomology can be included in heteroduplex structures.

This article has been cited by other articles:

				J. Radicella, P. Park, and M. Fox Adaptive mutation in Escherichia coli: a role for conjugation Science, April 21, 1995; 268(5209): 418 - 420. [Abstract] [PDF]