title: Distinct Streptococcus thermophilus bacteriophages share an extremely conserved DNA fragment.
abstract: A cross-hybridizing 2.2-kb EcoRI fragment was cloned from two lytic Streptococcus thermophilus bacteriophages with distinct phenotypes. The DNA fragments, which contained two unidentified open reading frames, differed at only 3 of 2207 nucleotide positions. Partial sequencing of a temperate S. thermophilus phage and of a further lytic phage belonging to a different lytic group isolated 20 years earlier from a different geographical area confirmed this extreme sequence conservation. Hybridization of this phage DNA with bacterial host DNA was not observed. The evolutionary implications of these observations are briefly discussed.
authors.affiliation: Nestlé Research Centre, Nestec Ltd., Vers-chez-les-Blanc, Lausanne, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Brüssow
authors.forename: A
authors.initials: A
authors.lastname: Probst
authors.forename: M
authors.initials: M
authors.lastname: Frémont
authors.forename: J
authors.initials: J
authors.lastname: Sidoti
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D004279:DNA, Viral / Q000235:genetics*; D008892:Milk / Q000382:microbiology*; D008969:Molecular Sequence Data; D017108:Streptococcus Phages / Q000145:classification* / Q000235:genetics* / Q000254:growth & development
chemical_list: D004279:DNA, Viral