Nucleic Acids Research, 1979, Vol. 6, No. 5 1979-1991
© 1979
Articles |
Heterodupkxes of 
174 and G4 DNAs: orientation to genetic map and comparison with predictions from nucleotide sequences
Department of Molecular Biology and Biochemistry, University of California Irvine, CA 9271 7, USA
Received January 2, 1979.
Heteroduplexes between the viral DNA of 
174 and DNA from the replicative form (RF) of phage G4 were examined by electron microscopy. The single Eco RI site of G4-RF was utilized as a physical marker by preparing the heteroduplexes from the denatured, linear DNA obtained by restricting Ge-RB with Eco RI endonuclease. Restriction fragments of x were used in a separate series of heteroduplexes to align the hete map and the G4 Eco RI site with the similar genetic maps of the two phages. The positions of the branch migreting junctions of recombinant X-G4 figure-8s, previously located only with respect to the G4 Eco RI site, have now been located with high probability within the gene A region of the two genomea. The degree of mismatch between the known nucleotide sequences of x end G4 accounts for positions of all of the regions of single-strendedmess in the observed heteroduplexes, but unexplained discrepancies were also found.