Phage P1: Difference between revisions
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The genome of P1 is about 94 kb with atleast 117 genes that are organized in 45 operons. Protein-coding genes occupy 92% of the genome. 4 of the 45 operons are responsible for the choice between lysis and lysogeny and another 4 are responsible for plasmid maintenance. The remaining 37 are invovled in lytic development. Regulatory regions of 38 operons contain one or more sequences that resemble strong δ<sup>70</sup> promoters. In the virion, DNA is double stranded, linear, terminally redundant and circularly permuted. | The genome of P1 is about 94 kb with atleast 117 genes that are organized in 45 operons. Protein-coding genes occupy 92% of the genome. 4 of the 45 operons are responsible for the choice between lysis and lysogeny and another 4 are responsible for plasmid maintenance. The remaining 37 are invovled in lytic development. Regulatory regions of 38 operons contain one or more sequences that resemble strong δ<sup>70</sup> promoters. In the virion, DNA is double stranded, linear, terminally redundant and circularly permuted. The terminal redundant region is important because foreign pieces of DNA can be inserted in non-essential regions. | ||
== Life cycle == | == Life cycle == | ||
Revision as of 16:56, 10 November 2011
Bacteriophage P1 Phage P1 was isolated in 1951 by Giuseppe Bertani from the Escherichia coli strain of Lisbonne and Carrere. [1]. P1 has been widely used to construct new batcterial strains and was used extensively to map the Escherichia Coli chromosome. P1 has served as a model organism for different aspects of phage and biology such as DNA restriction modification[2][3],site-specific recombination[4], plasmid replication[5], partition[6], incompatibility[7] and addiction[8]
Morphology
Phage P1 exhibits the classical bacteriophage morphology with an icosahedral head, 220nm long inflexible tail with a complete tube surrounded by a contractile sheath, baseplate and six kinked tail fibers. The icosahedral head contains the phage genome. A variable part(encoded by an invertible segment of P1 DNA) of the tail fibers(1 to 2nm thick) determines the specificity of P1 adsorption on different hosts.[9]
Genome Organization
AF234172.1 on NCBI AF234173.1 on NCBI
<gbrowseImage> name=NC_005856:44,801..94,800 source=bacteriophage_P1 width=800 type=Genes </gbrowseImage>
The genome of P1 is about 94 kb with atleast 117 genes that are organized in 45 operons. Protein-coding genes occupy 92% of the genome. 4 of the 45 operons are responsible for the choice between lysis and lysogeny and another 4 are responsible for plasmid maintenance. The remaining 37 are invovled in lytic development. Regulatory regions of 38 operons contain one or more sequences that resemble strong δ70 promoters. In the virion, DNA is double stranded, linear, terminally redundant and circularly permuted. The terminal redundant region is important because foreign pieces of DNA can be inserted in non-essential regions.
Life cycle
Lytic cycle
Adsorbtion and Injection
Early gene expression
Middle gene expression
DNA replication
The Cre-lox mechanism was discovered in P1 bacteriophage as part of this organism's normal viral live cycle (Sauer and Henderson 1988; Sternberg and Hamilton 1981). The bacteriophage uses Cre-lox recombination to circularize and facilitate replication of its genomic DNA when reproducing (FIND MORE INFO)
Late gene expression
Packaging
Lysis
Lysogenic state
Lysis-Lysogeny switch
Prophage induction
See also
- Phage P1 Gene List
- NC 005856 on NCBI
- GenBank record for P1
- Phage P1 Taxonomy on NCBI
- International Committee on Taxonomy of Viruses
- Wikipedia: Phage P1
References
See Help:References for how to manage references in EcoliWiki.
- ↑ BERTANI, G (1951) Studies on lysogenesis. I. The mode of phage liberation by lysogenic Escherichia coli. J. Bacteriol. 62 293-300 PubMed
- ↑ ARBER, W & DUSSOIX, D (1962) Host specificity of DNA produced by Escherichia coli. I. Host controlled modification of bacteriophage lambda. J. Mol. Biol. 5 18-36 PubMed
- ↑ DUSSOIX, D & ARBER, W (1962) Host specificity of DNA produced by Escherichia coli. II. Control over acceptance of DNA from infecting phage lambda. J. Mol. Biol. 5 37-49 PubMed
- ↑ Hamilton, DL & Abremski, K (1984) Site-specific recombination by the bacteriophage P1 lox-Cre system. Cre-mediated synapsis of two lox sites. J. Mol. Biol. 178 481-6 PubMed
- ↑ Chattoraj, DK (2000) Control of plasmid DNA replication by iterons: no longer paradoxical. Mol. Microbiol. 37 467-76 PubMed
- ↑ Austin, S & Abeles, A (1983) Partition of unit-copy miniplasmids to daughter cells. I. P1 and F miniplasmids contain discrete, interchangeable sequences sufficient to promote equipartition. J. Mol. Biol. 169 353-72 PubMed
- ↑ Sternberg, N et al. (1981) Group Y incompatibility and copy control of P1 prophage. Plasmid 5 138-49 PubMed
- ↑ Lehnherr, H et al. (1993) Plasmid addiction genes of bacteriophage P1: doc, which causes cell death on curing of prophage, and phd, which prevents host death when prophage is retained. J. Mol. Biol. 233 414-28 PubMed
- ↑ Łobocka, MB et al. (2004) Genome of bacteriophage P1. J. Bacteriol. 186 7032-68 PubMed