To use all functions of this page, please activate cookies in your browser.
my.chemeurope.com
With an accout for my.chemeurope.com you can always see everything at a glance – and you can configure your own website and individual newsletter.
- My watch list
- My saved searches
- My saved topics
- My newsletter
FokI (biology)The enzyme FokI, naturally found in Flavobacterium okeanokoites, is a bacterial type IIS restriction endonuclease consisting of an N-terminal DNA-binding domain and a non-specific DNA cleavage domain at the C-terminal.[1] Once the protein is bound to duplex DNA via its DNA-binding domain at the 5'-GGATG-3': 5'-CATCC-3' recognition site, the DNA cleavage domain is activated and cleaves non-specifically between nine and 13 nucleotides downstream of the recognition site.[2] Its molecular mass is 65.4 kDa, being comprised of 587 amino acids. Additional recommended knowledge
DNA-binding domainThe recognition domain contains three subdomains (D1, D2 and D3) that are evolutionarily related to the DNA-binding domain of the catabolite gene activator protein which contains a helix-turn-helix.[2] DNA-cleavage domainDNA cleavage is mediated through the non-specific cleavage domain which also includes the dimerisation surface.[3] The dimer interface is formed by the parallel helices α4 and α5 and two loops P1 and P2 of the cleavage domain.[2] ActivityWhen the nuclease is unbound to DNA, the endonuclease domain is sequestered by the DNA-binding domain and is released through a conformational change in the DNA-binding domain upon binding to its recognition site. Cleavage only occurs upon dimerisation, when the recognition domain is bound to its cognate site and in the presence of magnesium ions.[3] ExploitationThe endonuclease domain of FokI has been used in several studies, after combination with a variety of DNA-binding domains such as the zinc finger (see zinc finger nuclease).[1] One of several human vitamin D receptor gene variants is a single nucleotide polymorphism in the start codon of the gene which can be distinguished through the use of the FokI enzyme.[4] References
See also
Categories: Bacterial enzymes | Restriction enzymes |
|
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "FokI_(biology)". A list of authors is available in Wikipedia. |