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List Of Restriction Enzyme Cutting Sites
A restriction enzyme or restriction endonuclease is a special type of biological macromolecule that functions as part of the "immune system" in bacteria. One special kind of restriction enzymes is the class of " homing endonucleases", these being present in all three domains of life, although their function seems to be very different from one domain to another. The classical restriction enzymes cut up, and hence render harmless, any unknown (non- cellular) DNA that enters a bacterial cell as a result of a viral infection. They recognize a specific DNA sequence, usually short (3 to 8 bp), and cut it, producing either blunt or overhung ends, either at or nearby the recognition site. Restriction enzymes are quite variable in the short DNA sequences they recognize. An organism often has several different enzymes, each specific to a distinct short DNA sequence. :''See the main article on restriction enzyme''. :''Further reading: Homing endonuclease''. __TOC__ Restriction enzymes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Restriction Enzyme
A restriction enzyme, restriction endonuclease, REase, ENase or'' restrictase '' is an enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites. Restriction enzymes are one class of the broader endonuclease group of enzymes. Restriction enzymes are commonly classified into five types, which differ in their structure and whether they cut their DNA substrate at their recognition site, or if the recognition and cleavage sites are separate from one another. To cut DNA, all restriction enzymes make two incisions, once through each sugar-phosphate backbone (i.e. each strand) of the DNA double helix. These enzymes are found in bacteria and archaea and provide a defense mechanism against invading viruses. Inside a prokaryote, the restriction enzymes selectively cut up ''foreign'' DNA in a process called ''restriction digestion''; meanwhile, host DNA is protected by a modification enzyme (a methyltransferase) that modifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EMBL
The European Molecular Biology Laboratory (EMBL) is an intergovernmental organization dedicated to molecular biology research and is supported by 27 member states, two prospect states, and one associate member state. EMBL was created in 1974 and is funded by public research money from its member states. Research at EMBL is conducted by approximately 110 independent research and service groups and teams covering the spectrum of molecular biology and bioinformatics. The list of Groups and Teams at EMBL can be found at . The Laboratory operates from six sites: the main laboratory in Heidelberg, and sites in Hinxton (the European Bioinformatics Institute (EBI), in England), Grenoble (France), Hamburg (Germany), Rome (Italy) and Barcelona (Spain). EMBL groups and laboratories perform basic research in molecular biology and molecular medicine as well as train scientists, students, and visitors. The organization aids in the development of services, new instruments and methods, and techno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swiss-Prot
UniProt is a freely accessible database of protein sequence and functional information, many entries being derived from genome sequencing projects. It contains a large amount of information about the biological function of proteins derived from the research literature. It is maintained by the UniProt consortium, which consists of several European bioinformatics organisations and a foundation from Washington, DC, United States. The UniProt consortium The UniProt consortium comprises the European Bioinformatics Institute (EBI), the Swiss Institute of Bioinformatics (SIB), and the Protein Information Resource (PIR). EBI, located at the Wellcome Trust Genome Campus in Hinxton, UK, hosts a large resource of bioinformatics databases and services. SIB, located in Geneva, Switzerland, maintains the ExPASy (Expert Protein Analysis System) servers that are a central resource for proteomics tools and databases. PIR, hosted by the National Biomedical Research Foundation (NBRF) at the Geor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
I-CreI
I-''Cre''I is a homing endonuclease whose gene was first discovered in the chloroplast genome of ''Chlamydomonas reinhardtii'', a species of unicellular green algae. It is named for the facts that: it resides in an Intron; it was isolated from ''Clamydomonas reinhardtii''; it was the first (I) such gene isolated from ''C. reinhardtii''. Its gene resides in a group I intron in the 23S ribosomal RNA gene of the ''C. reinhardtii'' chloroplast, and I-''Cre''I is only expressed when its mRNA is spliced from the primary transcript of the 23S gene. I-''Cre''I enzyme, which functions as a homodimer, recognizes a 22-nucleotide sequence of duplex DNA and cleaves one phosphodiester bond on each strand at specific positions. I-''Cre''I is a member of the LAGLIDADG family of homing endonucleases, all of which have a conserved LAGLIDADG amino acid motif that contributes to their associative domains and active sites. When the I-''Cre''I-containing intron encounters a 23S allele lacking the intr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intragenomic Conflict
Intragenomic conflict refers to the evolutionary phenomenon where genes have phenotypic effects that promote their own transmission in detriment of the transmission of other genes that reside in the same genome. The selfish gene theory postulates that natural selection will increase the frequency of those genes whose phenotypic effects cause their transmission to new organisms, and most genes achieve this by cooperating with other genes in the same genome to build an organism capable of reproducing and/or helping kin to reproduce. The assumption of the prevalence of intragenomic cooperation underlies the organism-centered concept of inclusive fitness. However, conflict among genes in the same genome may arise both in events related to reproduction (a selfish gene may "cheat" and increase its own presence in gametes or offspring above the expected according to fair Mendelian segregation and fair gametogenesis) and altruism (genes in the same genome may disagree on how to value ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intron
An intron is any nucleotide sequence within a gene that is not expressed or operative in the final RNA product. The word ''intron'' is derived from the term ''intragenic region'', i.e. a region inside a gene."The notion of the cistron .e., gene... must be replaced by that of a transcription unit containing regions which will be lost from the mature messenger – which I suggest we call introns (for intragenic regions) – alternating with regions which will be expressed – exons." (Gilbert 1978) The term ''intron'' refers to both the DNA sequence within a gene and the corresponding RNA sequence in RNA transcripts. The non-intron sequences that become joined by this RNA processing to form the mature RNA are called exons. Introns are found in the genes of most organisms and many viruses and they can be located in both protein-coding genes and genes that function as RNA (noncoding genes). There are four main types of introns: tRNA introns, group I introns, group II introns, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BglII
''Bgl''II is a type II restriction endonuclease isolated from certain strains of '' Bacillus globigii''. The principal function of restriction enzymes is the protection of the host genome against foreign DNA, but they may also have some involvement in recombination and transposition. Like most type II restriction enzymes, ''Bgl''II consists of two identical subunits that form a homodimer around the DNA double helix. Each monomer is 223 amino acids and symmetrically bind both sides of the unique palindromic nucleotide sequence AGATCT, cleaving the scissile phosphodiester bond between the first Adenine and Guanine nucleotides on both strands of the DNA molecule, creating sticky ends with 5' end overhangs. Being a type II restriction enzyme, ''Bgl''II does not require ATP (adenosine triphosphate) for its enzymatic function, but only requires association with a divalent metal cation, most likely Mg2+. Unlike other restriction enzymes of its class, ''Bgl''II has been shown to p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HindIII
''Hin''dIII (pronounced "Hin D Three") is a type II site-specific deoxyribonuclease restriction enzyme isolated from ''Haemophilus influenzae'' that cleaves the DNA palindromic sequence AAGCTT in the presence of the cofactor Mg2+ via hydrolysis. The cleavage of this sequence between the AA's results in 5' overhangs on the DNA called sticky ends: 5'-A , A G C T T-3' 3'-T T C G A, A-5' Restriction endonucleases are used as defense mechanisms in prokaryotic organisms in the restriction modification system. Their primary function is to protect the host genome against invasion by foreign DNA, primarily bacteriophage DNA. There is also evidence that suggests the restriction enzymes may act alongside modification enzymes as selfish elements, or may be involved in genetic recombination and transposition. Enzyme Structure The structure of HindIII is complex, and consists of a homodimer. Like other type II restriction endonucleases, it is believed to contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EcoRI
''Eco''RI (pronounced "eco R one") is a restriction endonuclease enzyme isolated from species '' E. coli.'' It is a restriction enzyme that cleaves DNA double helices into fragments at specific sites, and is also a part of the restriction modification system. The ''Eco'' part of the enzyme's name originates from the species from which it was isolated - "E" denotes generic name which is "Escherichia" and "co" denotes species name, "coli" - while the R represents the particular strain, in this case RY13, and the I denotes that it was the first enzyme isolated from this strain. In molecular biology it is used as a restriction enzyme. ''Eco''RI creates 4 nucleotide sticky ends with 5' end overhangs of AATT. The nucleic acid recognition sequence where the enzyme cuts is G↓AATTC, which has a palindromic, complementary sequence of CTTAA↓G. Other restriction enzymes, depending on their cut sites, can also leave 3' overhangs or blunt ends with no overhangs. Structure Primary str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoschizomer
Isoschizomers are pairs of restriction enzymes specific to the same recognition sequence. For example, SphI (CGTAC/G) and BbuI (CGTAC/G) are isoschizomers of each other. The first enzyme discovered which recognizes a given sequence is known as the prototype; all subsequently identified enzymes that recognize that sequence are isoschizomers. Isoschizomers are isolated from different strains of bacteria and therefore may require different reaction conditions. In some cases, only one out of a pair of isoschizomers can recognize both the methylated as well as unmethylated forms of restriction sites. In contrast, the other restriction enzyme can recognize only the unmethylated form of the restriction site. This property of some isoschizomers allows identification of methylation state of the restriction site while isolating it from a bacterial strain. For example, the restriction enzymes HpaII and MspI are isoschizomers, as they both recognize the sequence 5'-CCGG-3' when it is unme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
