The short version of tripeptide fits in a sentence. The long version — which is the one that helps — is below.
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Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. It occurs in nearly all living cells, with highest concentrations in liver, kidney, and red blood cells, and exists in reduced (GSH) and oxidized disulfide (GSSG) forms. The cysteine thiol group enables reversible oxidation and reduction reactions. This property makes glutathione a central participant in cellular redox balance. The balance between these forms is often used as an indicator of oxidative stress.
Glutathione synthesis proceeds in two ATP-dependent steps catalyzed by glutamate-cysteine ligase and glutathione synthetase. The first step joins glutamate and cysteine to form gamma-glutamylcysteine and is generally rate-limiting. The second step adds glycine to complete the tripeptide. Cysteine availability, feedback inhibition by glutathione, and oxidative conditions influence flux through this pathway. The pathway is conserved across many organisms, and degradation by gamma-glutamyl transpeptidase and related peptidases recycles amino acids for new synthesis.
Within cells, glutathione serves as a cofactor for glutathione peroxidases and glutathione S-transferases. These enzymes reduce hydrogen peroxide and organic peroxides or conjugate electrophilic compounds to the thiol group. The resulting conjugates can be exported and processed through mercapturic acid pathways. Glutathione also contributes to protein thiol homeostasis and to recycling of other antioxidants such as ascorbate. Its precise roles vary by tissue, and many regulatory effects observed in laboratory systems remain difficult to quantify in whole organisms.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. The peptide bond between glutamate and cysteine uses the gamma-carboxyl group of glutamate rather than the alpha-carboxyl group. This unusual linkage protects the molecule from many common peptidases. The cysteine side chain carries a thiol group that can undergo reversible oxidation. Because of this thiol, glutathione participates in redox reactions and helps maintain the reducing environment inside most cells in living systems.
In cells, glutathione exists mainly in a reduced form called GSH. When two GSH molecules react, they form oxidized glutathione, or GSSG, which contains a disulfide bond. The ratio of GSH to GSSG is often used as an indicator of oxidative stress. Enzymes such as glutathione peroxidase and glutathione reductase help cycle the molecule between these two states. This cycling supports antioxidant defense, detoxification of reactive molecules, and regulation of certain signaling pathways.
Glutathione is present in most tissues, with especially high concentrations in the liver. It also serves as a cofactor for some enzymes and helps transport amino acids across cell membranes. In plants and microorganisms, glutathione contributes to stress responses and metal handling. The molecule is synthesized in two ATP-dependent steps, first producing gamma-glutamylcysteine and then adding glycine. Because cysteine availability often limits synthesis, dietary and metabolic factors can influence glutathione levels. Research continues to examine how these levels relate to health and disease.
| Property | Value | Notes |
|---|---|---|
| Common name | Glutathione | Reduced form is abbreviated GSH |
| Chemical class | Tripeptide | Composed of glutamate, cysteine, and glycine |
| Molar mass | 307.32 g/mol | For reduced glutathione |
| CAS Registry Number | 70-18-8 | For reduced L-glutathione |
| Appearance | White crystalline powder | Typical solid reference material |
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. Its cysteine residue carries a thiol group, which allows the molecule to participate in reduction and oxidation reactions. The compound exists in most living cells, where the reduced form, often abbreviated GSH, is usually more abundant than the oxidized disulfide form, GSSG. Intracellular concentrations are commonly in the millimolar range, while extracellular concentrations are much lower. This uneven distribution supports its role as a major cellular redox buffer.
Cells synthesize glutathione through two ATP-dependent enzymatic steps. The first step combines glutamate and cysteine to form gamma-glutamylcysteine, catalyzed by glutamate-cysteine ligase. The second step adds glycine, producing the complete tripeptide, catalyzed by glutathione synthetase. Glutathione itself can inhibit the first enzyme, providing negative feedback when levels are high. Because cysteine is often limiting, its availability influences how quickly the pathway proceeds. These reactions occur in the cytosol, and the resulting glutathione can be distributed to other compartments.
Synthesis occurs in two ATP-dependent steps: glutamate-cysteine ligase joins glutamate and cysteine to form gamma-glutamylcysteine, and glutathione synthetase adds glycine to complete the tripeptide. The pathway is feedback-inhibited by GSH and limited by cysteine availability, so cysteine supply often constrains production. Once formed, GSH participates in redox buffering, xenobiotic conjugation, and protein glutathionylation. Glutathione peroxidase uses GSH to reduce hydrogen peroxide and lipid peroxides, yielding GSSG, while glutathione reductase regenerates GSH using NADPH. Glutathione S-transferases conjugate electrophiles to GSH, supporting detoxification and excretion.
Because GSH is central to redox balance, its status is studied in aging, liver disease, neurodegenerative conditions, and metabolic disorders. Observational studies often report lower GSH or higher GSSG in affected tissues, but such associations do not establish that raising glutathione changes disease outcomes. Oral glutathione is digested into amino acids, and whether intact absorption occurs remains debated; precursors such as N-acetylcysteine and cysteine donors are also investigated. Regulatory agencies generally treat glutathione as a dietary supplement, not an approved drug, and clinical claims require evidence from controlled trials.
(WINNER) The contestant won the whole competition. ‡ The contestant won the Pre-Heat challenge. (WIN) The contestant won the Main Heat challenge. (HIGH) The contestant had one of the best dishes for that week. (IN) The contestant performed well enough to move on to the next week. (LOW) The contestant had one of the bottom dishes for that week, but was not eliminated. (OUT) The contestant was eliminated for worst dish.
On March 20, 1976, Marrow's high school girlfriend Adrienne gave birth to their daughter LeTesha Marrow, and they continued attending high school while raising her. While filming Breakin' in 1984, he met his second girlfriend Darlene Ortiz, who was at the club where the film was shot. They began a relationship and Ortiz was featured on the covers of Rhyme Pays and Power. Ice-T and Ortiz had a son, Ice Tracy Marrow Jr., on November 23, 1991; Ice Marrow, aka "Little Ice", became a backing vocalist with Body Count in time for the recording of their album Carnivore. Ice-T married swimsuit model Coco Austin in January 2002. In celebration of their impending ninth wedding anniversary, the couple renewed their wedding vows on June 4, 2011. As of 2006, they owned a penthouse apartment in North Bergen, New Jersey. In 2012, they were building a five-bedroom house in Edgewater, New Jersey, that was expected to be completed by the end of the year. In 2015, the couple had their first child together, a daughter. Ice-T has stated on numerous occasions that he is a teetotaler, and lives a straight edge lifestyle. He is a long time practitioner of Brazilian Jiu-Jitsu and boxing, and is a big fan of the UFC.
If we can't hold ourselves up as an example of how to treat people with dignity and respect, we can't ask that other nations do that to our soldiers." On May 1, 2004, photos of prisoners at Abu Ghraib prison in Iraq being abused and humiliated by United States soldiers provoke an international outrage. Furthering the charges, excerpts from the Abu Ghraib Taguba report were published on May 3, 2004. The report documented: the sodomizing of a prisoner with a chemical light, pouring phosphoric liquid on detainees, rape of a female prisoner, forced masturbation, "ghost detainees" moved around to avoid the Red Cross, and many other abuses. The release of the photographs and reports had led to renewed calls for investigations into the abuses reported in other US military prisons, such as Camp X-Ray and Camp Delta. On May 14, 2004, reporters for the Guardian documented a coercive technique which soldiers called "bitch in a box". The prisoner was shoved into the trunk of a car on a hot day, and driven around until the prisoner was near ready to pass out. Another technique documented was "waterboarding", which involves water being poured over a cloth covering the face and breathing passages of an immobilized captive, causing the individual to experience the sensation of drowning. They also interviewed many soldiers not involved in the current scandal, who claimed that they were taught to use sleep deprivation, to stage mock executions, and to use other procedures. One platoon leader who objected to these practices was reportedly told that his stand could end his military career.
Sources: en.wikipedia.org
== Historiography of Knoxville == The East Tennessee Historical Society's annual journal, published since 1929, contains numerous articles on Knoxville and Knoxville-area topics. The Society has also published two comprehensive histories of Knoxville and Knox County, The French Broad-Holston Country (1946), edited by Mary Utopia Rothrock, and Heart of the Valley (1976), edited by Lucile Deaderick. In 1982, the Society published a follow-up to Heart of the Valley, William MacArthur's Knoxville: Crossroads of the New South, which includes hundreds of historic photographs. Other comprehensive histories of the city include William Rule's Standard History of Knoxville (1900) and Ed Hooper's Knoxville (2003), the latter being part of Arcadia's "Images of America" series. The Civil War is one of the most extensively covered periods of Knoxville's history. Two early first-hand accounts of the war in Knoxville are William G. Brownlow's Sketches of the Rise, Progress and Decline of Secession (1862) and the diary of Ellen Renshaw House, edited by Daniel Sutherland and published as A Very Violent Rebel: The Civil War Diary of Ellen Renshaw House (1996). First-hand accounts written after the war include William Rule's The Loyalists of Tennessee in the Late War (1887), Thomas Williams Humes's The Loyal Mountaineers of Tennessee (1888), Oliver Perry Temple's East Tennessee and the Civil War (1899), and Albert Chavannes's East Tennessee Sketches (1900).
== Etymology == Medicine (UK: , US: ) is the science and practice of the diagnosis, prognosis, treatment, and prevention of disease. The word "medicine" is derived from Latin medicus, meaning "a physician". The word "physic" itself, from which "physician" derives, was the old word for what is now called a medicine, and also the field of medicine.
== History == Orexigen Therapeutics submitted a New Drug Application (NDA) for the combination to the FDA in March 2010. Having paid a fee under the Prescription Drug User Fee Act, Orexigen was given a deadline for the FDA to approve or reject the drug of January 2011. In December 2010, an FDA Advisory Committee voted 13–7 to approve Contrave and 11–8 to conduct a post-marketing cardiovascular outcomes study. Subsequently, on 2 February 2011, the FDA rejected the drug, and it was decided that an extremely large-scale study of the long-term cardiovascular effects of Contrave would be needed before approval could be considered. It was ultimately approved in the United States in 2014. In December 2014, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency endorsed the combination for licensure as an obesity medication when used alongside diet and exercise. Authorization was granted in March 2015. A review of Mysimba was completed by the CHMP in March 2025. In May 2015, Orexigen prematurely ended the trial that was intended to test whether naltrexone/bupropion increased the risk of major adverse cardiovascular events in obese patients with cardiovascular disease because an independent panel of experts said that the drug maker "inappropriately" compromised the trial by prematurely releasing interim data. The early data release reported a reduction in heart attacks, but that advantage was no longer observed when a more complete view of the data was analyzed.
Sources: en.wikipedia.org
Wound dehiscence is a surgical complication in which a wound ruptures along a surgical incision. Risk factors include age, collagen disorder such as Ehlers–Danlos syndrome, diabetes, obesity, poor knotting or grabbing of stitches, and trauma to the wound after surgery.
Despite these obstacles to their synthesis, a 2013 study published by a group of Russian physicists led by Valeriy Zagrebaev proposes that the longest-lived copernicium isotopes may occur at an abundance of 10−12 relative to lead, whereby they may be detectable in cosmic rays. Similarly, in a 2013 experiment, a group of Russian physicists led by Aleksandr Bagulya reported the possible observation of three cosmogenic superheavy nuclei in olivine crystals in meteorites. The atomic number of these nuclei was estimated to be between 105 and 130, with one nucleus likely constrained between 113 and 129, and their lifetimes were estimated to be at least 3,000 years. Although this observation has yet to be confirmed in independent studies, it strongly suggests the existence of the island of stability, and is consistent with theoretical calculations of half-lives of these nuclides. The decay of heavy, long-lived elements in the island of stability is a proposed explanation for the unusual presence of the short-lived radioactive isotopes observed in Przybylski's Star.
Although developing, telomerase inhibition within malignant cancer cells can theoretically be used as a potential treatment. Real-time reverse transcription polymerase chain reaction (RT-PCR) quantifying hTERT expression in various tumor samples verified this varying expression. Telomeres in non-cancerous human cells are generally longer than in cancer cells, and telomerase-inhibiting therapy aims to selectively suppress telomerase activity in cancer cells while preserving normal telomerase activity in non-tumor cells. Telomere-targeted treatments include oligonucleotides, nucleosides, small molecule inhibitors, and more. Various natural compounds have been identified as having telomerase inhibitory properties, such as oleic acid, a fatty acid found in vegetable and animal oils.
Dubnium is a synthetic chemical element; it has symbol Db and atomic number 105. It is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of about 16 hours. This greatly limits extended research on the element. Dubnium does not occur naturally on Earth and is produced artificially. The Soviet Joint Institute for Nuclear Research (JINR) claimed the first discovery of the element in 1968, followed by the American Lawrence Berkeley Laboratory in 1970. Both teams proposed their names for the new element and used them without formal approval. The long-standing dispute was resolved in 1993 by an official investigation of the discovery claims by the Transfermium Working Group, formed by the International Union of Pure and Applied Chemistry and the International Union of Pure and Applied Physics, resulting in credit for the discovery being officially shared between both teams. The element was formally named dubnium in 1997 after the town of Dubna, the site of the JINR. Theoretical research establishes dubnium as a member of group 5 in the 6d series of transition metals, placing it under vanadium, niobium, and tantalum. Dubnium should share most properties, such as its valence electron configuration and having a dominant +5 oxidation state, with the other group 5 elements, with a few anomalies due to relativistic effects. A limited investigation of dubnium chemistry has confirmed this.
Sources: en.wikipedia.org
GSH is the reduced thiol form, while GSSG is the disulfide-linked oxidized dimer. The GSH:GSSG ratio is used as a redox indicator, though the ratio can vary with sample handling and cell type.
Glutathione is present in many foods, including meats, poultry, fish, some vegetables, and fruits. Cooking, storage, and digestion affect the amounts available for absorption.
Yes, both enzymatic steps in glutathione synthesis consume ATP. The first step, catalyzed by glutamate-cysteine ligase, is usually rate-limiting.
Glutathione is a tripeptide made from glutamate, cysteine, and glycine. Its cysteine residue provides a thiol group that is central to its redox activity. The glutamate-cysteine bond forms through the gamma-carboxyl group of glutamate.