A
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 o ...
or restriction
endonuclease
Endonucleases are enzymes that cleave the phosphodiester bond within a polynucleotide chain. Some, such as deoxyribonuclease I, cut DNA relatively nonspecifically (without regard to sequence), while many, typically called restriction endonucleases ...
is a special type of biological
macromolecule
A macromolecule is a very large molecule important to biophysical processes, such as a protein or nucleic acid. It is composed of thousands of covalently bonded atoms. Many macromolecules are polymers of smaller molecules called monomers. The ...
that functions as part of the "
immune system
The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splinte ...
" in
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
. One special kind of restriction enzymes is the class of "
homing endonucleases
The homing endonucleases are a collection of endonucleases encoded either as freestanding genes within introns, as fusions with host proteins, or as self-splicing inteins. They catalyze the hydrolysis of genomic DNA within the cells that synth ...
", 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
Cellular may refer to:
*Cellular automaton, a model in discrete mathematics
* Cell biology, the evaluation of cells work and more
* ''Cellular'' (film), a 2004 movie
*Cellular frequencies, assigned to networks operating in cellular RF bands
*Cell ...
)
DNA that enters a bacterial cell as a result of a
viral infection
A viral disease (or viral infection) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles (virions) attach to and enter susceptible cells.
Structural Characteristics
Basic structural characteristics, s ...
. 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
A recognition sequence is a DNA sequence to which a structural motif of a DNA-binding domain exhibits binding specificity. Recognition sequences are palindromes.
The transcription factor Sp1 for example, binds the sequences 5'-(G/T)GGGCGG(G/A)( ...
.
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
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 o ...
''.
:''Further reading:
Homing endonuclease
The homing endonucleases are a collection of endonucleases encoded either as freestanding genes within introns, as fusions with host proteins, or as self-splicing inteins. They catalyze the hydrolysis of genomic DNA within the cells that synthes ...
''.
__TOC__
Restriction enzymes catalog
The list includes some of the most studied examples of
restriction endoncleases. The following information is given:
The whole list contains more than 1,200 enzymes, but databases register about 4,000.
To make a list that is accessible to navigation, this list has been divided into different pages. Each page contains somewhere between 120-150 entries. Choose a letter to go to a specific part of the list:
Notes and references
See also
*
List of homing endonuclease cutting sites
The homing endonucleases are a special type of restriction enzymes encoded by introns or inteins. They act on the cellular DNA of the cell that synthesizes them; to be precise, in the opposite allele of the gene that encode them.
Homing endonucl ...
*
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 o ...
.
*
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 th ...
.
* Detailed articles about certain restriction enzymes:
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 modific ...
,
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 ...
,
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 invo ...
.
*
Homing endonuclease
The homing endonucleases are a collection of endonucleases encoded either as freestanding genes within introns, as fusions with host proteins, or as self-splicing inteins. They catalyze the hydrolysis of genomic DNA within the cells that synthes ...
.
*
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. ...
s and
inteins.
* Intragenomic conflict:
Homing endonuclease genes
The homing endonucleases are a collection of endonucleases encoded either as freestanding genes within introns, as fusions with host proteins, or as self-splicing inteins. They catalyze the hydrolysis of genomic DNA within the cells that synthes ...
.
*
I-CreI homing endonuclease.
External links
''Databases and lists of restriction enzymes:''
* Very comprehensive database of restriction enzymes supported by New England Biolabs. It includes all kind of biological, structural, kinetical and commercial information about thousands of enzymes. Also includes related literature for every molecule:
* Detailed information for biochemical experiments:
* Alphabetical list of enzymes and their restriction sites:
* General information about restriction sites and biochemical conditions for restriction reactions:
''Databases of proteins:''
* Database of structures of proteins, solved at atomic resolution:
* Databases of proteins:
{{DEFAULTSORT:List Of Restriction Enzyme Cutting Sites
Biotechnology
Restriction enzyme cutting sites
Restriction enzymes
Enzymes
Proteins