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Deoxyribose-phosphate Aldolase
The enzyme deoxyribose-phosphate aldolase () catalyzes the reversible chemical reaction :2-deoxy-D-ribose 5-phosphate \rightleftharpoons D-glyceraldehyde 3-phosphate + acetaldehyde This enzyme belongs to the family of lyases, specifically the aldehyde-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is 2-deoxy-D-ribose-5-phosphate acetaldehyde-lyase (D-glyceraldehyde-3-phosphate-forming). Other names in common use include phosphodeoxyriboaldolase, deoxyriboaldolase, deoxyribose-5-phosphate aldolase, 2-deoxyribose-5-phosphate aldolase, and 2-deoxy-D-ribose-5-phosphate acetaldehyde-lyase. Enzyme Mechanism Amongst aldolases, DERA is unique as it is the only enzyme to afford two aldehydes as products. Crystallography shows that the enzyme is a Class I aldolase, so the mechanism proceeds via the formation of a Schiff base with Lys167 at the active site. A nearby residue, Lys201, is critical to reaction by increasing the acidity of protonated Lys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stress Granules
Stress granules are dense aggregations in the cytosol composed of proteins and RNAs that appear when the cell is under stress. The RNA molecules stored are stalled translation pre-initiation complexes: failed attempts to make protein from mRNA. Stress granules are 100–200 nm in size (when biochemically purified), not surrounded by membrane, and associated with the endoplasmatic reticulum. Note that there are also nuclear stress granules. This article is about the cytosolic variety. Proposed functions The function of stress granules remains largely unknown. Stress granules have long been proposed to have a function to protect RNAs from harmful conditions, thus their appearance under stress. The accumulation of RNAs into dense globules could keep them from reacting with harmful chemicals and safeguard the information coded in their RNA sequence. Stress granules might also function as a decision point for untranslated mRNAs. Molecules can go down one of three paths: further ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directed Evolution
Directed evolution (DE) is a method used in protein engineering that mimics the process of natural selection to steer proteins or nucleic acids toward a user-defined goal. It consists of subjecting a gene to iterative rounds of mutagenesis (creating a library of variants), selection (expressing those variants and isolating members with the desired function) and amplification (generating a template for the next round). It can be performed ''in vivo'' (in living organisms), or ''in vitro'' (in cells or free in solution). Directed evolution is used both for protein engineering as an alternative to rationally designing modified proteins, as well as for experimental evolution studies of fundamental evolutionary principles in a controlled, laboratory environment. History Directed evolution has its origins in the 1960s with the evolution of RNA molecules in the " Spiegelman's Monster" experiment. The concept was extended to protein evolution via evolution of bacteria under select ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crotonaldehyde
Crotonaldehyde is a chemical compound with the formula CH3CH=CHCHO. The compound is usually sold as a mixture of the ''E''- and ''Z''-isomers, which differ with respect to the relative position of the methyl and formyl groups. The ''E''-isomer is more common (data given in Table is for the ''E''-isomer). This lachrymatory liquid is moderately soluble in water and miscible in organic solvents. As an unsaturated aldehyde, crotonaldehyde is a versatile intermediate in organic synthesis. It occurs in a variety of foodstuffs, e.g. soybean oils. Production and reactivity Crotonaldehyde is produced by the aldol condensation of acetaldehyde: :2 CH3CHO → CH3CH=CHCHO + H2O Crotonaldehyde is a multifunctional molecule that exhibits diverse reactivity. It is a prochiral dienophile. It is a Michael acceptor. Addition of methylmagnesium chloride produces 3-penten-2-ol. Polyurethane catalyst ''N'',''N'',''N''′,''N''′-tetramethyl-1,4-butanediamine (also known as NIAX TMBDA) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mevastatin
Mevastatin (compactin, ML-236B) is a hypolipidemic agent that belongs to the statins class. It was isolated from the mold ''Penicillium citrinum'' by Akira Endo in the 1970s, and he identified it as a HMG-CoA reductase inhibitor, i.e., a statin. Mevastatin might be considered the first statin drug; clinical trials on mevastatin were performed in the late 1970s in Japan, but it was never marketed. The first statin drug available to the general public was lovastatin. Mevastatin has since been derivatized to the compound pravastatin, which is a pharmaceutical used in the lowering of cholesterol and preventing cardiovascular disease. ''In vitro'', it has antiproliferative properties. A British group isolated the same compound from ''Penicillium brevicompactum'', named it ''compactin'', and published their results in 1976. The British group mentions antifungal properties with no mention of HMG-CoA reductase inhibition. High doses inhibit growth and proliferation of melanoma cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosuvastatin
Rosuvastatin, sold under the brand name Crestor among others, is a statin medication, used to prevent cardiovascular disease in those at high risk and treat abnormal lipids. It is recommended to be used together with dietary changes, exercise, and weight loss. It is taken by mouth. Common side effects include abdominal pain, nausea, headaches, and muscle pains. Serious side effects may include rhabdomyolysis, liver problems, and diabetes. Use during pregnancy may harm the baby. Like all statins, rosuvastatin works by inhibiting HMG-CoA reductase, an enzyme found in the liver that plays a role in producing cholesterol. Rosuvastatin was patented in 1991, and approved for medical use in the United States in 2003. It is available as a generic medication. In 2020, it was the seventeenth most commonly prescribed medication in the United States, with more than 29million prescriptions. There have been criticisms of rosuvastatin having worse adverse effects despite effectively reduc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atorvastatin
Atorvastatin is a statin medication used to prevent cardiovascular disease in those at high risk and to treat abnormal lipid levels. For the prevention of cardiovascular disease, statins are a first-line treatment. It is taken by mouth. Common side effects include joint pain, diarrhea, heartburn, nausea, and muscle pains. Serious side effects may include rhabdomyolysis, liver problems, and diabetes. Use during pregnancy may harm the fetus. Like all statins, atorvastatin works by inhibiting HMG-CoA reductase, an enzyme found in the liver that plays a role in producing cholesterol. Atorvastatin was patented in 1986, and approved for medical use in the United States in 1996. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. In 2020, it was the most commonly prescribed medication in the United States, with more than 114million prescriptions. Medical uses The primary uses of atorvastatin is for the treatment of dyslipide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dera Lipitor
Dera, Dero, Daro, Dhoro, Dahar or Dehra is a word in several languages of South Asia, whose meaning is 'camp', 'mound' or 'settlement'. It appears in the names of a number of places. Geography India * Dera, Himachal Pradesh * Dera Bassi, Mohali district, Punjab * Dera Baba Nanak, Gurdaspur district, Punjab * Dera Baba Jaimal Singh, Amritsar district, Punjab * Dera Baba Murad Shah, Nakodar, Punjab * Dera Baba Vadbhag Singh, Una district, Himachal Pradesh * Dera Doon, capital of Uttarakhand * Dera Sach Khand Ballan, Jalandhar district, Punjab * Dera Sacha Sauda, Sirsa district, Haryana * Dera Sar, Jain temples in Gujarat and Rajasthan * Dera Kanjli, Kapurthala district, Punjab * Dera Gopipur, Kangra district, Himachal Pradesh * Gola Dhoro, Kutch district, Gujarat * Kerala-no-dhoro, Saurashtra, Gujarat * Damajino Dero, Vadodara district, Gujarat Iran * Dera, Iran, a village in Kerman Province, Iran * Dera, Kohgiluyeh and Boyer-Ahmad, a village in Kohgiluyeh and Boyer-Ahmad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Islatravir
Islatravir (4′-ethynyl-2-fluoro-2′-deoxyadenosine, EFdA, or MK-8591) is an investigational drug for the treatment of HIV infection. It is classified as a nucleoside reverse transcriptase translocation inhibitor (NRTTI). Merck is developing a subdermal drug-eluting implant to administer islatravir. Biological activity Islatravir has activity against HIV in animal models, and is being studied clinically for HIV treatment and prophylaxis. Islatravir is a nucleoside analog reverse transcriptase A reverse transcriptase (RT) is an enzyme used to generate complementary DNA (cDNA) from an RNA template, a process termed reverse transcription. Reverse transcriptases are used by viruses such as HIV and hepatitis B to replicate their genomes, ... translocation inhibitor that unlike other such inhibitors, inhibits HIV through multiple mechanisms, providing rapid suppression of the virus, when tested in macaques and mice. Nevertheless, there are HIV strains resistant to islatravir a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleoside Reverse Transcriptase Inhibitors
Reverse-transcriptase inhibitors (RTIs) are a class of antiretroviral drugs used to treat HIV infection or AIDS, and in some cases hepatitis B. RTIs inhibit activity of reverse transcriptase, a viral DNA polymerase that is required for replication of HIV and other retroviruses. Mechanism of action When HIV infects a cell, reverse transcriptase copies the viral single stranded RNA genome into a double-stranded viral DNA. The viral DNA is then integrated into the host chromosomal DNA, which then allows host cellular processes, such as transcription and translation, to reproduce the virus. RTIs block reverse transcriptase's enzymatic function and prevent completion of synthesis of the double-stranded viral DNA, thus preventing HIV from multiplying. A similar process occurs with other types of viruses. The hepatitis B virus, for example, carries its genetic material in the form of DNA, and employs an RNA-dependent DNA polymerase to replicate. Some of the same compounds used as RTIs c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dera Islatravir
Dera, Dero, Daro, Dhoro, Dahar or Dehra is a word in several languages of South Asia, whose meaning is 'camp', 'mound' or 'settlement'. It appears in the names of a number of places. Geography India * Dera, Himachal Pradesh * Dera Bassi, Mohali district, Punjab * Dera Baba Nanak, Gurdaspur district, Punjab * Dera Baba Jaimal Singh, Amritsar district, Punjab * Dera Baba Murad Shah, Nakodar, Punjab * Dera Baba Vadbhag Singh, Una district, Himachal Pradesh * Dera Doon, capital of Uttarakhand * Dera Sach Khand Ballan, Jalandhar district, Punjab * Dera Sacha Sauda, Sirsa district, Haryana * Dera Sar, Jain temples in Gujarat and Rajasthan * Dera Kanjli, Kapurthala district, Punjab * Dera Gopipur, Kangra district, Himachal Pradesh * Gola Dhoro, Kutch district, Gujarat * Kerala-no-dhoro, Saurashtra, Gujarat * Damajino Dero, Vadodara district, Gujarat Iran * Dera, Iran, a village in Kerman Province, Iran * Dera, Kohgiluyeh and Boyer-Ahmad, a village in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uncoupler
An uncoupler or uncoupling agent is a molecule that disrupts oxidative phosphorylation in prokaryotes and mitochondria or photophosphorylation in chloroplasts and cyanobacteria by dissociating the reactions of ATP synthesis from the electron transport chain. The result is that the cell or mitochondrion expends energy to generate a proton-motive force, but the proton-motive force is dissipated before the ATP synthase can recapture this energy and use it to make ATP. Uncouplers are capable of transporting protons through mitochondrial and lipid membranes. Description Classical uncouplers have five properties: # the complete release of respiratory control # the substitution of all coupled processes (ATP synthesis, transhydrogenation, reverse electron flow, active transport of cations, etc.) by a cyclic proton transport mediated by the uncoupler # the elimination of all protonic and cationic gradients generated across the mitochondrial or prokaryotic membrane # no discrimination in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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