title: Extended host range of a beta-related corynebacteriophage.
abstract: Unlike most beta-related phages isolated from Corynebacterium diphtheriae, phage 782 readily plaqued on strains of C. ulcerans and C. pseudotuberculosis. The extended host range of phage 782 was not, however, due to a greater ability of the phage to absorb to bacterial surfaces. Using chemical mutagenesis, a number of phage mutants were isolated which had diminished capacities to infect C. ulcerans, suggesting the existence of a locus (ehr) for extended host range. Pre-lysogenization of C. ulcerans strains with phage 782, but not its mutant form or other beta-related phages, rendered them susceptible to infection by previously excluded phages. An examination of recombinant between phages 782, pie, and beta localized ehr to a 7 kilobase region of DNA including attP. The data are compatible with the notion that ehr encodes an anti-restriction function.
authors.affiliation: Department of Microbiology and Immunology, Northwestern University, Chicago, IL 60611, USA.
authors.forename: N P
authors.initials: NP
authors.lastname: Cianciotto
authors.forename: N B
authors.initials: NB
authors.lastname: Groman
mesh_terms: D001435:Bacteriophages / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D002874:Chromosome Mapping; D003352:Corynebacterium / Q000821:virology*; D003353:Corynebacterium diphtheriae / Q000821:virology; D016679:Genome, Viral; D008242:Lysogeny; D009154:Mutation; D013045:Species Specificity