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Nucleases
In biochemistry, a nuclease (also archaically known as nucleodepolymerase or polynucleotidase) is an enzyme capable of cleaving the phosphodiester bonds that link nucleotides together to form nucleic acids. Nucleases variously affect single and double stranded breaks in their target molecules. In living organisms, they are essential machinery for many aspects of DNA repair. Defects in certain nucleases can cause genetic instability or immunodeficiency. Nucleases are also extensively used in molecular cloning. There are two primary classifications based on the locus of activity. Exonucleases digest nucleic acids from the ends. Endonucleases act on regions in the ''middle'' of target molecules. They are further subcategorized as deoxyribonucleases and ribonucleases. The former acts on DNA, the latter on RNA. History In the late 1960s, scientists Stuart Linn and Werner Arber isolated examples of the two types of enzymes responsible for phage growth restriction in Escherichia col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deoxyribonuclease
Deoxyribonuclease (DNase, for short) refers to a group of glycoprotein endonucleases which are enzymes that catalyze the hydrolytic cleavage of phosphodiester linkages in the DNA backbone, thus degrading DNA. The role of the DNase enzyme in cells includes breaking down extracellular DNA (ecDNA) excreted by apoptosis, necrosis, and neutrophil extracellular traps (NET) of cells to help reduce inflammatory responses that otherwise are elicited. A wide variety of deoxyribonucleases are known and fall into one of two families ( DNase I or DNase II), which differ in their substrate specificities, chemical mechanisms, and biological functions. Laboratory applications of DNase include purifying proteins when extracted from prokaryotic organisms. Additionally, DNase has been applied as a treatment for diseases that are caused by ecDNA in the blood plasma. Assays of DNase are emerging in the research field as well. Types The two main types of DNase found in animals are known as deoxy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HindIII Restriction Site And Sticky Ends Vector
HindIII (pronounced "Hin D Three") is a type II site-specific deoxyribonuclease restriction enzyme isolated from ''Haemophilus influenzae ''Haemophilus influenzae'' (formerly called Pfeiffer's bacillus or ''Bacillus influenzae'') is a Gram-negative, Motility, non-motile, Coccobacillus, coccobacillary, facultative anaerobic organism, facultatively anaerobic, Capnophile, capnophili ...'' 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 enzym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Werner Arber
Werner Arber (born 3 June 1929 in Gränichen, Aargau) is a Swiss microbiologist and geneticist. Along with American researchers Hamilton Smith and Daniel Nathans, Werner Arber shared the 1978 Nobel Prize in Physiology or Medicine for the discovery of restriction endonucleases. Their work would lead to the development of recombinant DNA technology. Life and career Arber studied chemistry and physics at the Swiss Federal Institute of Technology in Zürich from 1949 to 1953. Late in 1953, he took an assistantship for electron microscopy at the University of Geneva, in time left the electron microscope, went on to research bacteriophages and write his dissertation on defective lambda prophage mutants. In his Nobel Autobiography, he writes: In the summer of 1956, we learned about experiments made by Larry Morse and Esther and Joshua Lederberg on the lambda-mediated transduction (gene transfer from one bacterial strain to another by a bacteriophage serving as vector) of bacterial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union Of Biochemistry And Molecular Biology
The International Union of Biochemistry and Molecular Biology (IUBMB) is an international non-governmental organisation concerned with biochemistry and molecular biology. Formed in 1955 as the International Union of Biochemistry (IUB), the union has presently 79 member countries and regions (as of 2020).IUBMB: the first half-century. /ref> The Union is devoted to promoting research and education in biochemistry and molecular biology throughout the world, and gives particular attention to localities where the subject is still in its early development. History The first Congress of Bioche ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Commission Number
The Enzyme Commission number (EC number) is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. As a system of enzyme nomenclature, every EC number is associated with a recommended name for the corresponding enzyme-catalyzed reaction. EC numbers do not specify enzymes but enzyme-catalyzed reactions. If different enzymes (for instance from different organisms) catalyze the same reaction, then they receive the same EC number. Furthermore, through convergent evolution, completely different protein folds can catalyze an identical reaction (these are sometimes called non-homologous isofunctional enzymes) and therefore would be assigned the same EC number. By contrast, UniProt identifiers uniquely specify a protein by its amino acid sequence. Format of number Every enzyme code consists of the letters "EC" followed by four numbers separated by periods. Those numbers represent a progressively finer classification of the enzyme. Preliminary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haemophilus Influenzae
''Haemophilus influenzae'' (formerly called Pfeiffer's bacillus or ''Bacillus influenzae'') is a Gram-negative, Motility, non-motile, Coccobacillus, coccobacillary, facultative anaerobic organism, facultatively anaerobic, Capnophile, capnophilic pathogenic bacterium of the family Pasteurellaceae. The bacteria are Mesophile, mesophilic and grow best at temperatures between 35 and 37 °C. ''H. influenzae'' was first described in 1893 by Richard Friedrich Johannes Pfeiffer, Richard Pfeiffer during an influenza pandemic when he incorrectly identified it as the causative microbe, which is why the bacteria was given the name "influenzae". ''H. influenzae'' is responsible for a wide range of localized and invasive infections, typically in infants and children, including pneumonia, meningitis, or bloodstream infections. Treatment consists of antibiotics; however, ''H. influenzae'' is often resistant to the penicillin family, but amoxicillin/clavulanic acid can be used in mild cases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johns Hopkins University
The Johns Hopkins University (often abbreviated as Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland, United States. Founded in 1876 based on the European research institution model, Johns Hopkins is considered to be the first research university in the U.S. The university was named for its first benefactor, the American entrepreneur and Quakers, Quaker philanthropist Johns Hopkins. Hopkins's $7 million bequest (equivalent to $ in ) to establish the university was the largest Philanthropy, philanthropic gift in U.S. history up to that time. Daniel Coit Gilman, who was inaugurated as :Presidents of Johns Hopkins University, Johns Hopkins's first president on February 22, 1876, led the university to revolutionize higher education in the U.S. by integrating teaching and research. In 1900, Johns Hopkins became a founding member of the Association of American Universities. The university has led all Higher education in the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas J
Clarence Thomas (born June 23, 1948) is an American lawyer and jurist who has served since 1991 as an associate justice of the Supreme Court of the United States. President George H. W. Bush Clarence Thomas Supreme Court nomination, nominated him to succeed Thurgood Marshall. After Marshall, Thomas is the second African Americans, African American to serve on the U.S. Supreme Court and has been its List of United States Supreme Court justices by time in office, longest-serving member since Anthony Kennedy's retirement in 2018. He has also been the Court's oldest member since Stephen Breyer retired in 2022. Thomas was born in Pin Point, Georgia. After his father abandoned the family, he was raised by his grandfather in a poor Gullah community near Savannah, Georgia. Growing up as a devout Catholic, Thomas originally intended to be a priest in the Catholic Church but became dissatisfied with its efforts to combat racism and abandoned his aspiration to join the clergy. He gradua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamilton O
Hamilton may refer to: * Alexander Hamilton (1755/1757–1804), first U.S. Secretary of the Treasury and one of the Founding Fathers of the United States * ''Hamilton'' (musical), a 2015 Broadway musical by Lin-Manuel Miranda ** ''Hamilton'' (album), album based on the musical ** '' The Hamilton Mixtape'', album of music from the musical performed by various artists ** ''Hamilton'' (2020 film), a live film recording of the musical, featuring the original cast Hamilton may also refer to: People * Hamilton (name), a common British surname and occasional given name, usually of Scottish origin, including a list of persons with the surname ** The Duke of Hamilton, the premier peer of Scotland ** Lord Hamilton (other), several Scottish, Irish and British peers, and some members of the judiciary, who may be referred to simply as ''Hamilton'' ** Clan Hamilton, an ancient Scottish kindred * Hamílton (footballer, born 1980), Togolese footballer * Lewis Hamilton (race driver, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cut And Paste
Cut, copy, and paste are essential commands of modern human–computer interaction and user interface design. They offer an interprocess communication technique for transferring data through a computer's user interface. The ''cut'' command removes the selected data from its original position, and the ''copy'' command creates a duplicate; in both cases the selected data is kept in temporary storage called the clipboard. Clipboard data is later inserted wherever a ''paste'' command is issued. The data remains available to any application supporting the feature, thus allowing easy data transfer between applications. The command names are an interface metaphor based on the physical procedure used in manuscript print editing to create a page layout, like with paper. The commands were pioneered into computing by Xerox PARC in 1974, popularized by Apple Computer in the 1983 Lisa workstation and the 1984 Macintosh computer, and in a few home computer applications such as the 1984 wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Restriction Nuclease
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 modifies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
