Genome and proteome characterization of the psychrophilic Flavobacterium bacteriophage 11b
- 414 Downloads
Virion DNA of bacteriophage 11b (Φ11b), which infects a psychrophilic Flavobacterium isolate from Arctic sea-ice, was determined to consist of 36,012 bp. With 30.6% its GC content corresponds to that of host-genus species and is the lowest of all phages of Gram-negative bacteria sequenced so far. Similarities of several of 65 predicted ORFs, genome organization and phylogeny suggest an affiliation to ‘mesophilic’ nonmarine siphoviruses, e.g. to bacteriophages SPP1 and HK97. Early genes presumably encode an essential recombination factor (ERF), a single strand binding (SSB) protein, an endonuclease, and a DNA methylase. The late gene segment is likely to contain a terminase, portal, minor head, protease and a major capsid gene. Five ORFs exhibited similarities to Bacteroidetes species and seem to reflect the host specificity of the phage. Among PAGE-separated virion proteins that were identified by MALDI-ToF mass spectrometry are the portal, the major capsid, and a putative conserved tail protein. The Φ11b genome is the first to be described of a cultivated virus infecting a psychrophilic host as well as a Bacteroidetes bacterium.
KeywordsPsychrophilic Flavobacterium bacteriophage Φ11b Genomics Proteome Low GC
We thank Hansjörg Lehnherr for critical reading of the manuscript and Dr. Steffen Krüger for helpful comments during the sequencing and sequence assembly procedure. We are grateful for the support of Michael Hecker in the analysis of the phage proteome.
- Ackermann H-W, Abedon ST (2001) Bacteriophage names. The Bacteriophage Ecology Group. (Online.) http://www.phage.org/names.htm
- Bernardet J-F, Segers P, Vancanneyt M, Berthe F, Kersters K, Vandamme P (1996) Cutting a Gordian knot: emended classification and description of the genus Flavobacterium, emended description of the family Flavobacteriaceae, and proposal of Flavobacterium hydatis nom. nov. (basonym, Cytophaga aquatilis Strohl and Tait 1978). Int J Syst Bacteriol 46:128–148CrossRefGoogle Scholar
- Bradford D, Hugenholtz P, Seviour EM, Cunningham MA, Stratton H, Seviour RJ, Blackall LL (1996) 16S rRNA analysis of isolates obtained from gram-negative filamentous bacteria micromanipulated from activated sludge. Syst Appl Microbiol 19:334–343Google Scholar
- Combet C, Blanchet C, Geourjon C, Deléage G (2000) NPS@: Network Protein Sequence Analysis TIBS 25:147–150Google Scholar
- Gasteiger E, Hoogland C, Gattiker A, Duvaud S, Wilkins MR, Appel RD, Bairoch A (2005) Protein identification and analysis tools on the ExPASy server. In Walker JM (eds) The proteomics protocols handbook. Humana Press, pp 571–607Google Scholar
- Teeling H., Lombardot T, Bauer M, Ludwig W, Glöckner FO (2004) Evaluation of the phylogenetic position of the planctomycete ‘Rhodopirellula baltica’ SH 1 by means of concatenated ribosomal protein sequences, DNA-directed RNA polymerase subunit sequences and whole genome trees. Int J Syst Evol Microbiol 54:791–801PubMedCrossRefGoogle Scholar