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| Bacteriophage λ is the archetype of the [[Lambdoid phage|lambdoid]], or lambda-like phage, a subclass of the [http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/02.066.htm siphoviridae]. λ is a temperate phage.
| | #REDIRECT [[Phage_lambda]] |
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| == Morphology ==
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| The λ phage has an icosahedral head about 50 nm in diameter, and a flexible tail about 150nm long.<ref name='LIB:Lambda_II'/> The head contains a single double-stranded DNA molecule about 48 kb in length; by weight the genome is about 32x10<sup>6</sup> Da and comprises about half of the phage's weight.<ref name='LIB:Lambda_II'/> The DNA is linear when packaged, and recircularizes at the ''cos'' ('''co'''hesive end '''s'''ite) once injected into the host. <ref name='LIB:Lambda_II'/>
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| == Genome Organization ==
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| == Life Cycle ==
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| === Lytic Cycle ===
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| The lytic cycle is the usual life cycle, and results in the death of the host bacteria.
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| ==== Adsorbtion and Injection ====
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| The tip of the phage tail ([[Phage_lambda_J:Gene_Product(s)|J protein]]) attaches to the host cell protein [[lamB]], which is displayed on the outer membrane.<ref name='LIB:Lambda_II'/> The dsDNA is injected through the tail as a linear genome, when the phage tail interacts with the inner membrane protein [[ptsM]] and recircularizes once inside the host due to complementary 12nt long sticky ends. <ref name='LIB:Lambda_II'/>
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| ==== Early Gene Expression ====
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| The cro gene is an immediate-early gene product.<ref name='LIB:BofV'/>
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| CII and CIII are delayed-early gene products. <ref name='LIB:BofV'/>
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| ==== Middle Gene Expression ====
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| ==== DNA Replication ====
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| ==== Late Gene Expression ====
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| ==== Packaging ====
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| ==== Lysis ====
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| === Lysogenic State ===
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| The lysogenic lifecycle is the result of integration of the λ DNA into the host genome, and does not result in the death of the host cell. The λ DNA/host DNA unit is termed a prophage.
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| The λ DNA is integrated at the ''att''P (for '''att'''achment '''p'''hage) and the ''att''B (for '''att'''achment '''b'''acteria) loci.<ref name='LIB:BofV'/>
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| === Lysis-Lysogeny Switch ===
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| === Prophage Induction ===
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| == See also ==
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| *[http://ecoliwiki.net/colipedia/index.php/Category:Gene_List:Phage_lambda| Lambda Gene List]
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| *[http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=10710&lvl=3&lin=f&keep=1&srchmode=1&unlock Enterobacteriophage lambda at the NCBI taxonomy browser]
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| *[[wikipedia: Lambda_phage]]
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| *[http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/02.066.0.01.001.htm ICTVdb entry]
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| *[http://microbewiki.kenyon.edu/index.php/Siphoviridae Siphoviridae at MicrobeWiki]
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| *[http://www.uniprot.org/taxonomy/10710 Phage lambda on UniProt]
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| == References ==
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| {{RefHelp}}
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| <references/>
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| [[Category:lambda-like]]
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