* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download 34 Lambda Appendix - RIT
Nucleic acid analogue wikipedia , lookup
United Kingdom National DNA Database wikipedia , lookup
Genealogical DNA test wikipedia , lookup
Transposable element wikipedia , lookup
Epigenetics of human development wikipedia , lookup
DNA vaccination wikipedia , lookup
Nutriepigenomics wikipedia , lookup
Zinc finger nuclease wikipedia , lookup
Cancer epigenetics wikipedia , lookup
X-inactivation wikipedia , lookup
Gel electrophoresis of nucleic acids wikipedia , lookup
Human genome wikipedia , lookup
Mitochondrial DNA wikipedia , lookup
DNA damage theory of aging wikipedia , lookup
Primary transcript wikipedia , lookup
Gene expression programming wikipedia , lookup
Nucleic acid double helix wikipedia , lookup
Genetic engineering wikipedia , lookup
Epigenomics wikipedia , lookup
Minimal genome wikipedia , lookup
Cell-free fetal DNA wikipedia , lookup
Genome (book) wikipedia , lookup
Point mutation wikipedia , lookup
Deoxyribozyme wikipedia , lookup
Molecular cloning wikipedia , lookup
Non-coding DNA wikipedia , lookup
DNA supercoil wikipedia , lookup
Designer baby wikipedia , lookup
Extrachromosomal DNA wikipedia , lookup
Genome editing wikipedia , lookup
History of genetic engineering wikipedia , lookup
Microevolution wikipedia , lookup
Genome evolution wikipedia , lookup
Therapeutic gene modulation wikipedia , lookup
No-SCAR (Scarless Cas9 Assisted Recombineering) Genome Editing wikipedia , lookup
Vectors in gene therapy wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Genomic library wikipedia , lookup
Helitron (biology) wikipedia , lookup
Appendix IX Bacteriophage λ The mature λ map is a 48.6 kb long linear double-stranded DNA with 11-basepair overhanging cohesive single-stranded tails on either end. The chromosome is divided into three general regions – left arm, right arm, and central region. The right arm contains genes involved in replication and lysis and the right arm contains genes for phage maturation. The central region controls lysogeny and superinfection immunity. When λ enters a susceptible cell, the single-stranded tails anneal to generate a circle. The site formed by the single stranded tails is called COS (cohesive site) and the left and right arms become contiguous and form a single operon, the right hand operon. The central region comprises a second operon, the left hand operon. λ is a temperate phage, meaning that upon entering a cell, the phage may enter either the lysogenic or lytic cycle. During lysogeny, there is a site-specific recombination event between the λ att site and a primary insertion site on the host chromosome adjacent to the lac operon. This event is mediated by the λ int gene. There are other, secondary insertion sites elsewhere on the host chromosome. There are thus three possible maps for λ, the linear mature map, the circular vegetative map, and a second linear map. In the mature map the ends are flanked by the COS site while in the lysogenic map the ends are flanked by the att site. 145 Appendix IX This site specific recombination event is reversible. If a lysogen is presented with DNA damage, in the form of ultraviolet light, for example, the int gene together with the xis gene perform the reverse site-specific recombination event and excise the phage from the host genome, restoring it to the circular vegetative map, and the phage then enters the lytic cycle. This process is called induction. Apart from DNA damage, spontaneous induction occurs at low levels. During the lytic phase, λ undergoes two replication phases, early and late. In the early phase, λ replicates via the Cairns or theta mode to produce multiple circular genomes. During late phase, the phage switches to rolling circle or sigma mode to produce mature linear phage genomes. Packaging is performed by a “headfull” process in which DNA is inserted into a pre-formed head. This imposes certain size restrictions that impact the use of λ as a cloning vector: maximum DNA length minimum DNA length kilobases 52.0 38.5 Percent of Genome Length 105 78 size of left + right arms 29.1 60 The mature λ map is a 48.6 kb long linear double-stranded DNA with 11-basepair overhanging cohesive single-stranded tails on either end. The chromosome is divided into three general regions – left arm, right arm, and central region. The right arm contains genes involved in replication and lysis and the right arm contains genes for phage maturation. The central region controls lysogeny and superinfection immunity. When λ enters a susceptible cell, the single-stranded tails anneal to generate a circle. The site formed by the single stranded tails is called COS (cohesive site) and the left and right arms become contiguous and form a single operon, the right hand operon. The central region comprises a second operon, the left hand operon. λ is a temperate phage, meaning that upon entering a cell, the phage may enter either the lysogenic or lytic cycle. During lysogeny, there is a site-specific recombination event between the λ att site and a primary insertion site on the host chromosome adjacent to the lac operon. This event is mediated by the λ int gene. There are other, secondary insertion sites elsewhere on the host chromosome. There are thus three possible maps for λ, the linear mature map, the circular vegetative map, and a second linear map. In the mature map the ends are flanked by the COS site while in the lysogenic map the ends are flanked by the att site. 146 Bacteriophage λ This site specific recombination event is reversible. If a lysogen is presented with DNA damage, in the form of ultraviolet light, for example, the int gene together with the xis gene perform the reverse sitespecific recombination event and excise the phage from the host genome, restoring it to the circular vegetative map, and the phage then enters the lytic cycle. This process is called induction. Apart from DNA damage, spontaneous induction occurs at low levels. During the lytic phase, λ undergoes two replication phases, early and late. In the early phase, λ replicates via the Cairns or theta mode to produce multiple circular genomes. During late phase, the phage switches to rolling circle or sigma mode to produce mature linear phage genomes. Packaging is performed by a “head-full” process in which DNA is inserted into a pre-formed head. This imposes certain size restrictions that impact the use of λ as a cloning vector: maximum DNA length minimum DNA length kilobases 52.0 38.5 Percent of Genome Length 105 78 size of left + right arms 29.1 60 147 Appendix IX Source: New England BioLabs 148