title: Physical map of the dispensable region of the genome of E. coli bacteriophage BF23.
abstract: Using 13 deletion mutants of bacteriophage BF23, physical as well as genetic structures of that portion of the genome which is dispensable for phage growth were investigated. The dispensable region covers at least 15% of the genome of wild type BF23, extending from about 0.2 to 0.35 map unit. Restriction endonuclease (EcoRI and HindIII) cleavage sites and the sites of single-strand interruptions in this dispensable region were localized. It was found that the dispensable region contains an interruption site, which is missing in the mutant BF23st(0) used by Okada and Shimura (1980). Wild-type phage DNA is heterogeneous in the presence or absence of specific single-strand interruptions in this or in a neighboring region of the genome.
mesh_terms: D002872:Chromosome Deletion; D002874:Chromosome Mapping; D003090:Coliphages / Q000235:genetics*; D004262:DNA Restriction Enzymes; D004277:DNA, Single-Stranded / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics*; D005814:Genes, Viral; D008970:Molecular Weight; D009691:Nucleic Acid Denaturation
chemical_list: D004277:DNA, Single-Stranded; D004279:DNA, Viral; D004262:DNA Restriction Enzymes