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EcoRV
''Eco''RV (pronounced "eco R five") is a type II restriction endonuclease isolated from certain strains of ''Escherichia coli''. It has the alternative name Eco32I. In molecular biology, it is a commonly used restriction enzyme. It creates blunt ends. The enzyme recognizes the palindromic 6-base DNA sequence 5'-GAT, ATC-3' and makes a blunt end at the vertical line. The complementary sequence is then 3'-CTA, TAG-5'. The ends are blunt and can be ligated into a blunt cloning site easily but with lower efficiency than sticky ends. Structure The structure of this enzyme, and several mutants, in complex with the DNA sequence which it cuts has been solved by X-ray crystallography. The core of the enzyme consists of a five-stranded mixed β-sheet flanked by α-helices. The core is conserved in all other type II restriction endonucleases. It also has an N-terminal dimerization subdomain formed by a short α-helix, a two-stranded antiparallel -sheet, and a long α-helix. This subdom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EcoRV Cleaving DNA
''Eco''RV (pronounced "eco R five") is a type II restriction endonuclease isolated from certain strains of ''Escherichia coli''. It has the alternative name Eco32I. In molecular biology, it is a commonly used restriction enzyme. It creates Sticky end/blunt end, blunt ends. The enzyme recognizes the palindromic 6-base DNA sequence 5'-GAT, ATC-3' and makes a blunt end at the vertical line. The complementary sequence is then 3'-CTA, TAG-5'. The ends are blunt and can be ligated into a blunt cloning site easily but with lower efficiency than sticky ends. Structure The structure of this enzyme, and several mutants, in complex with the DNA sequence which it cuts has been solved by X-ray crystallography. The core of the enzyme consists of a five-stranded mixed β-sheet flanked by α-helices. The core is conserved in all other type II restriction endonucleases. It also has an N-terminal dimerization subdomain formed by a short α-helix, a two-stranded antiparallel -sheet, and a long ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EcoRV Restriction Site
''Eco''RV (pronounced "eco R five") is a type II restriction endonuclease isolated from certain strains of ''Escherichia coli''. It has the alternative name Eco32I. In molecular biology, it is a commonly used restriction enzyme. It creates blunt ends. The enzyme recognizes the palindromic 6-base DNA sequence 5'-GAT, ATC-3' and makes a blunt end at the vertical line. The complementary sequence is then 3'-CTA, TAG-5'. The ends are blunt and can be ligated into a blunt cloning site easily but with lower efficiency than sticky ends. Structure The structure of this enzyme, and several mutants, in complex with the DNA sequence which it cuts has been solved by X-ray crystallography. The core of the enzyme consists of a five-stranded mixed β-sheet flanked by α-helices. The core is conserved in all other type II restriction endonucleases. It also has an N-terminal dimerization subdomain formed by a short α-helix, a two-stranded antiparallel -sheet, and a long α-helix. This subdo ... [...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] |
EcoRII
Restriction endonuclease (REase) EcoRII (pronounced "eco R two") is an enzyme of restriction modification system (RM) naturally found in ''Escherichia coli'', a Gram-negative bacteria. Its molecular mass is 45.2 kDa, being composed of 402 amino acids. Mode of action EcoRII is a bacterial Type IIE REase that interacts with two othreeref name="pmid17845057"> copies of the pseudopalindromic DNA recognition sequence 5'- CCW GG- 3' (W = A or T), one being the actual target of cleavage, the other(s) serving as the allosteric activator(s). EcoRII cuts the target DNA sequence CCWGG, generating sticky ends. Cut diagram Structure The apo crystal structure of EcoRII mutant R88A () has been solved at 2.1 Å resolution. The EcoRII monomer has two domains, N-terminal and C-terminal, linked through a hinge loop. Effector-binding domain The N-terminal effector-binding domain has an archetypal DNA-binding pseudobarrel fold () with a prominent cleft. Structural superposition sho ... [...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] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Biology
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physical structure of biological macromolecules is known as molecular biology. Molecular biology was first described as an approach focused on the underpinnings of biological phenomena - uncovering the structures of biological molecules as well as their interactions, and how these interactions explain observations of classical biology. In 1945 the term molecular biology was used by physicist William Astbury. In 1953 Francis Crick, James Watson, Rosalind Franklin, and colleagues, working at Medical Research Council unit, Cavendish laboratory, Cambridge (now the MRC Laboratory of Molecular Biology), made a double helix model of DNA which changed the entire research scenario. They proposed the DNA structure based on previous research done by Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FokI
The restriction endonuclease ''Fok''1, 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. Once the protein is bound to duplex DNA via its DNA-binding domain at the 5'-GGATG-3' recognition site, the DNA cleavage domain is activated and cleaves, without further sequence specificity, the first strand 9 nucleotides downstream and the second strand 13 nucleotides upstream of the nearest nucleotide of the recognition site. Its molecular mass is 65.4 kDa, being composed of 587 amino acids. DNA-binding domain The 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. DNA-cleavage domain DNA cleavage is mediated through the non-specific cleavage domain which also includes the dimerisation su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bovine Serum Albumin
Bovine serum albumin (BSA or "Fraction V") is a serum albumin protein derived from cows. It is often used as a protein concentration standard in lab experiments. The nickname "Fraction V" refers to albumin being the fifth fraction of the original Edwin Cohn purification methodology that made use of differential solubility characteristics of plasma proteins. By manipulating solvent concentrations, pH, salt levels, and temperature, Cohn was able to pull out successive "fractions" of blood plasma. The process was first commercialized with human albumin for medical use and later adopted for production of BSA. Properties The full-length BSA precursor polypeptide is 607 amino acids (AAs) in length. An N-terminal 18-residue signal peptide is cut off from the precursor protein upon secretion, hence the initial protein product contains 589 amino acid residues. An additional six amino acids are cleaved to yield the mature BSA protein that contains 583 amino acids. BSA has thre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Cloning
Molecular cloning is a set of experimental methods in molecular biology that are used to assemble recombinant DNA molecules and to direct their replication within host organisms. The use of the word ''cloning'' refers to the fact that the method involves the replication of one molecule to produce a population of cells with identical DNA molecules. Molecular cloning generally uses DNA sequences from two different organisms: the species that is the source of the DNA to be cloned, and the species that will serve as the living host for replication of the recombinant DNA. Molecular cloning methods are central to many contemporary areas of modern biology and medicine. In a conventional molecular cloning experiment, the DNA to be cloned is obtained from an organism of interest, then treated with enzymes in the test tube to generate smaller DNA fragments. Subsequently, these fragments are then combined with vector DNA to generate recombinant DNA molecules. The recombinant DNA is then i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recognition Sequence
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)(G/A)(C/T)-3', where (G/T) indicates that the domain will bind a guanine or thymine at this position. The restriction endonuclease PstI recognizes, binds, and cleaves the sequence 5'-CTGCAG-3'. A recognition sequence is different from a recognition site. A given recognition sequence can occur one or more times, or not at all, on a specific DNA fragment. A recognition site is specified by the position of the site. For example, there are two PstI recognition sites in the following DNA sequence fragment, starting at base 9 and 31 respectively. A recognition sequence is a specific sequence, usually very short (less than 10 bases). Depending on the degree of specificity of the protein, a DNA-binding protein can bind to more than one specific sequ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
