title: Mechanism of phage PS166-mediated biotype conversion in Vibrio cholerae: role of the hlyA locus.
abstract: Temperate phage PS166 lysogens of Vibrio eltor MAK757 biotype eltor belong to two major categories. Seventy percent of the lysogens acquire auxotrophy for glycine and histidine and maintain their parental biotype. About 10% of the lysogens become Cys(-) or Cys(-) Met(-) and are converted to the classical biotype with complete changes in all biotype-specific determinants. PCR and RFLP analysis revealed that in the latter lysogens, the phage genome integrated at the hlyA locus, whereas the same locus remained unaffected in lysogens that retained their parental biotype. These results suggest that the two types of lysogens arose due to integration of the phage genome at two different locations on the chromosome. A restriction map of the phage genome was constructed using AvaII and BglII. An 800-bp BglII fragment carrying the attP site, located at one of the termini of the phage genome, was used to distinguish the two classes of lysogen.
authors.affiliation: Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Calcutta, 700032, India.
authors.forename: R
authors.initials: R
authors.lastname: Mukhopadhyay
authors.forename: R K
authors.initials: RK
authors.lastname: Ghosh
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000502:physiology; D015373:Bacterial Typing Techniques; D001435:Bacteriophages / Q000235:genetics* / Q000502:physiology*; D015139:Blotting, Southern; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial / Q000235:genetics; D016679:Genome, Viral; D006460:Hemolysin Proteins / Q000235:genetics* / Q000502:physiology; D008242:Lysogeny / Q000235:genetics*; D016254:Mutagenesis, Insertional / Q000235:genetics; D015183:Restriction Mapping; D014734:Vibrio cholerae / Q000145:classification* / Q000235:genetics / Q000821:virology*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004279:DNA, Viral; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; D004262:DNA Restriction Enzymes