Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Quick Search
My eDoc
Session History
Support Wiki
Direct access to
document ID:

          Institute: MPI für molekulare Genetik     Collection: Microscopy     Display Documents

ID: 173723.0, MPI für molekulare Genetik / Microscopy
PY54, a linear plasmid prophage of Yersinia enterocolitica with covalently closed ends
Authors:Hertwig, Stefan; Klein, Iris; Lurz, Rudi; Lanka, Erich; Appel, Bernd
Date of Publication (YYYY-MM-DD):2003-05
Title of Journal:Molecular Microbiology
Journal Abbrev.:Mol. Microbiol.
Issue / Number:4
Start Page:989
End Page:1003
Review Status:not specified
Audience:Experts Only
Abstract / Description:PY54 is a temperate phage isolated from Yersinia enterocolitica. Lysogenic Yersinia strains harbour the PY54 prophage as a plasmid (pY54). The plasmid has the same size (46 kb) as the PY54 genome isolated from phage particles. By electron microscopy, restriction analysis and DNA sequencing, it was demonstrated that the phage and the plasmid DNAs are linear, circularly permuted molecules. Unusually for phages of Gram-negative bacteria, the phage genome has 3'-protruding ends. The linear plasmid pY54 has covalently closed ends forming telomere-like hairpins. The equivalent DNA sequence of the phage genome is a 42 bp perfect palindrome. Downstream from the palindrome, an open reading frame (ORF) was identified that revealed strong DNA homology to the telN gene of Escherichia coli phage N15 encoding a protelomerase. Similar to PY54, the N15 prophage is a linear plasmid with telomeres. The N15 protelomerase has cleaving/joining activity generating the telomeres by processing a 56 bp palindrome (telomere resolution site tel RL). To study the activity of the PY54 protein, the telN-like gene was cloned and expressed in E. coli. A 77 kDa protein was obtained and partially purified. The protein was found to process recombinant plasmids containing the 42 bp palindrome. Telomere resolution of plasmids under in vivo conditions was also investigated in Yersinia infected with PY54. Processing required a plasmid containing the palindrome as well as adjacent DNA sequences from the phage including an additional inverted repeat. Regions on the phage genome important for plasmid maintenance were defined by the construction of linear and circular miniplasmid derivatives of pY54, of which the smallest miniplasmid comprises a 4.5 kb DNA fragment of the plasmid prophage.
Comment of the Author/Creator:Date: 2003, May
External Publication Status:published
Document Type:Article
Version Comment:Automatic journal name synchronization
Communicated by:Rudi Lurz
Affiliations:MPI für molekulare Genetik
External Affiliations:Robert Koch Inst, Dept Biol Safety, D-13353 Berlin, Germany.; Max Planck Inst Mol Genet, D-14195 Berlin, Germany.
Identifiers:ISI:000182782600011 [ID No:1]
ISSN:0950-382X [ID No:2]
DOI:10.1046/j.1365-2958.2003.03458.x [ID No:3]
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.