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TE Buffer
TE buffer is a commonly used buffer solution in molecular biology, especially in procedures involving DNA, cDNA or RNA. "TE" is derived from its components: Tris, a common pH buffer, and EDTA, a molecule that chelation, chelates cations like Magnesium in biological systems, Mg2+. The purpose of TE buffer is to solubilize DNA or RNA, while protecting it from degradation. Recipe A typical recipe for making 1X TE buffer is: * 10 mM Tris, bring to pH 8.0 with HCl * 1 mM EDTA, bring to pH 8.0 with NaOH TE buffer is also called as T10E1 Buffer, and read as "T ten E one buffer". To make a 100 ml solution of T10E1 Buffer, 1 ml of 1 M Tris base (pH 10–11) and 0.2 ml EDTA (0.5 M) are mixed and made up with double distilled water up to 100ml. Add microliter amounts of high molarity HCl to lower the pH to 8. Based on nuclease studies from the 1980s, the pH is usually adjusted to 7.5 for RNA and 8.0 for DNA. The respective DNA and RNA nucleases are supposed to be less active at these pH ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buffer Solution
A buffer solution (more precisely, pH buffer or hydrogen ion buffer) is an aqueous solution consisting of a mixture of a weak acid and its conjugate base, or vice versa. Its pH changes very little when a small amount of strong acid or base is added to it. Buffer solutions are used as a means of keeping pH at a nearly constant value in a wide variety of chemical applications. In nature, there are many living systems that use buffering for pH regulation. For example, the bicarbonate buffering system is used to regulate the pH of blood, and bicarbonate also acts as a buffer in the ocean. Principles of buffering Buffer solutions resist pH change because of a chemical equilibrium between the weak acid HA and its conjugate base A−: When some strong acid is added to an equilibrium mixture of the weak acid and its conjugate base, hydrogen ions (H+) are added, and the equilibrium is shifted to the left, in accordance with Le Chatelier's principle. Because of this, the hydrogen io ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNase
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 metazoans are known as deoxyr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TAE Buffer
TAE buffer is a buffer solution containing a mixture of Tris base, acetic acid and EDTA. In molecular biology it is used in agarose electrophoresis typically for the separation of nucleic acids such as DNA and RNA. It is made up of Tris-acetate buffer, usually at pH 8.3, and EDTA, which sequesters divalent cations. TAE has a lower buffer capacity than TBE and can easily become exhausted, but linear, double stranded DNA runs faster in TAE. Previously, Brody & Kern simplified electrophoretic buffers by substituting TBE and TAE buffers for a more efficient and inexpensive conductive media in gel systems. Uses TAE (Tris-acetate-EDTA) buffer is used as both a running buffer and in agarose gels. Its use in denaturing gradient gel electrophoresis methods for broad-range mutation analysis has also been described. TAE has been used at various concentrations to study the mobility of DNA in solution with and without sodium chloride. However, high concentrations of sodium chloride (and man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LB Buffer
LB buffer, also known as lithium borate buffer, is a buffer solution used in agarose electrophoresis, typically for the separation of nucleic acids such as DNA and RNA. It is made up of Lithium borate (lithium hydroxide monohydrate and boric acid). LB(R) is a registered (USPTO) trademark of Faster Better Media LLC, which owns US patent 7,163,610 covering low-conductance lithium borate polynucleotide electrophoresis. Lithium Borate buffer has a lower conductivity, produces crisper resolution, and can be run at higher speeds than can gels made from TBE or TAE (5-50 V/cm as compared to 5-10 V/cm). At a given voltage, the heat generation and thus the gel temperature is much lower than with TBE/TAE buffers, therefore the voltage can be increased to speed up electrophoresis so that a gel run takes only a fraction of the usual time. Downstream applications, such as isolation of DNA from a gel slice or Southern blot analysis, work as expected with lithium boric acid gels. Brody, J.R. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymerase
A polymerase is an enzyme ( EC 2.7.7.6/7/19/48/49) that synthesizes long chains of polymers or nucleic acids. DNA polymerase and RNA polymerase are used to assemble DNA and RNA molecules, respectively, by copying a DNA template strand using base-pairing interactions or RNA by half ladder replication. A DNA polymerase from the thermophilic bacterium, ''Thermus aquaticus'' (''Taq'') ( PDBbr>1BGX EC 2.7.7.7) is used in the polymerase chain reaction, an important technique of molecular biology. A polymerase may be template dependent or template independent. Poly-A-polymerase is an example of template independent polymerase. Terminal deoxynucleotidyl transferase also known to have template independent and template dependent activities. Types By function *DNA polymerase (DNA-directed DNA polymerase, DdDP) **Family A: DNA polymerase I; Pol γ, θ, ν **Family B: DNA polymerase II; Pol α, δ, ε, ζ **Family C: DNA polymerase III holoenzyme **Family X: Pol β, λ, μ * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymerase Chain Reaction
The polymerase chain reaction (PCR) is a method widely used to rapidly make millions to billions of copies (complete or partial) of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it (or a part of it) to a large enough amount to study in detail. PCR was invented in 1983 by the American biochemist Kary Mullis at Cetus Corporation; Mullis and biochemist Michael Smith (chemist), Michael Smith, who had developed other essential ways of manipulating DNA, were jointly awarded the Nobel Prize in Chemistry in 1993. PCR is fundamental to many of the procedures used in genetic testing and research, including analysis of Ancient DNA, ancient samples of DNA and identification of infectious agents. Using PCR, copies of very small amounts of DNA sequences are exponentially amplified in a series of cycles of temperature changes. PCR is now a common and often indispensable technique used in medical laboratory research for a broad variety of applications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic table) it occurs naturally only in combination with other elements and it almost always has an oxidation state of +2. It reacts readily with air to form a thin passivation coating of magnesium oxide that inhibits further corrosion of the metal. The free metal burns with a brilliant-white light. The metal is obtained mainly by electrolysis of magnesium salts obtained from brine. It is less dense than aluminium and is used primarily as a component in strong and lightweight alloys that contain aluminium. In the cosmos, magnesium is produced in large, aging stars by the sequential addition of three helium nuclei to a carbon nucleus. When such stars explode as supernovas, much of the magnesium is expelled into the interstellar medium where it ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelating
Chelation is a type of bonding of ions and molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a Denticity, polydentate (multiple bonded) ligand and a single central metal atom. These ligands are called chelants, chelators, chelating agents, or sequestering agents. They are usually organic compounds, but this is not a necessity, as in the case of zinc and its use as a maintenance therapy to prevent the absorption of copper in people with Wilson's disease. Chelation is useful in applications such as providing nutritional supplements, in chelation therapy to remove toxic metals from the body, as contrast medium, contrast agents in MRI, MRI scanning, in manufacturing using homogeneous catalysts, in chemical water treatment to assist in the removal of metals, and in fertilizers. Chelate effect The chelate effect is the greater affinity of chelating ligands for a metal ion than that of similar nonchelating (monodentate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclease
A nuclease (also archaically known as nucleodepolymerase or polynucleotidase) is an enzyme capable of cleaving the phosphodiester bonds between nucleotides of nucleic acids. Nucleases variously effect 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 coli ( E. coli) bacteria. One of the ... [...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] |
NaOH
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates . The monohydrate crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, sodium hydroxide is frequently used alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students. Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and detergent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium In Biological Systems
Magnesium is an essential element in biological systems. Magnesium occurs typically as the Mg2+ ion. It is an essential mineral nutrient (i.e., element) for life and is present in every cell type in every organism. For example, adenosine triphosphate (ATP), the main source of energy in cells, must bind to a magnesium ion in order to be biologically active. What is called ATP is often actually Mg-ATP. As such, magnesium plays a role in the stability of all polyphosphate compounds in the cells, including those associated with the synthesis of DNA and RNA. Over 300 enzymes require the presence of magnesium ions for their catalytic action, including ''all'' enzymes utilizing or synthesizing ATP, or those that use other nucleotides to synthesize DNA and RNA. In plants, magnesium is necessary for synthesis of chlorophyll and photosynthesis. Function A balance of magnesium is vital to the well-being of all organisms. Magnesium is a relatively abundant ion in Earth's crust and mantle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
