Everything below concerns glutathione. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-06-13. Numbers and descriptions here follow the published literature rather than marketing material.
Commercial glutathione is produced by microbial fermentation or chemical synthesis, then purified. Reduced and oxidized grades are offered separately, with purity specifications often exceeding 98 percent. The compound appears in foods such as fresh fruits, vegetables, and meats, although cooking and processing can lower amounts. Oral, topical, and inhaled forms are discussed in research and consumer contexts, but absorption and tissue delivery remain active areas of study. Regulatory status varies by country and intended use.
Glutathione is a small sulfur-containing peptide built from glutamic acid, cysteine, and glycine. Its distinctive feature is a gamma-glutamyl bond between glutamate's side-chain carboxyl group and cysteine's amino group. This linkage resists ordinary peptidases and helps the molecule remain stable inside cells. The reduced thiol form, often abbreviated GSH, is the dominant intracellular species. The oxidized disulfide dimer, GSSG, forms when two reduced molecules link through their cysteine sulfur atoms. The balance between these forms is a common redox indicator.
Functionally, glutathione supports redox balance by donating electrons and becoming oxidized. It also serves as a cofactor for enzymes such as glutathione peroxidases and glutathione S-transferases. These enzymes participate in peroxide reduction and in conjugation reactions that help process reactive molecules. Separate from antioxidant roles, glutathione can modify protein cysteines through S-glutathionylation, influencing enzyme activity and signaling. Research continues to examine how these chemical roles translate into whole-organism effects.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. Its glutamate-cysteine linkage uses the gamma-carboxyl group of glutamate, a feature that resists standard peptidases. The cysteine residue provides a thiol group, which gives the molecule its reducing character. In cells, glutathione is often the most abundant small-molecule thiol, with concentrations varying widely by tissue and compartment. It exists mainly in a reduced form called GSH, while oxidation produces a disulfide-linked dimer called GSSG.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C10H17N3O6S | Reduced glutathione (GSH) |
| Molar mass | 307.32 g/mol | Oxidized dimer GSSG is 612.63 g/mol |
| Appearance | White to off-white crystalline powder | Typical purified solid |
| Solubility | Freely soluble in water; practically insoluble in ethanol | Polarity reflects multiple ionizable groups |
| Common synonyms | GSH; L-glutathione; γ-glutamylcysteinylglycine | 'Reduced' distinguishes it from GSSG |
Storage conditions strongly influence glutathione stability. The solid reduced form is commonly kept desiccated at or below minus twenty degrees Celsius, protected from light and moisture. Aqueous solutions are less stable because the thiol group reacts with dissolved oxygen, and oxidation accelerates at neutral or alkaline pH. Acidic solutions and oxygen-free handling can slow degradation, but repeated freeze-thaw cycles should be avoided. Researchers often verify concentration before use, because apparent losses can arise from oxidation or water uptake.
Measuring glutathione in biological samples requires attention to oxidation and matrix effects. High-performance liquid chromatography with ultraviolet or fluorescence detection can separate reduced and oxidized forms after derivatization. Liquid chromatography with tandem mass spectrometry offers higher specificity and can quantify glutathione alongside related thiols. Because glutathione can oxidize during sample handling, many protocols use rapid acidification with metaphosphoric acid or sulfosalicylic acid. Internal standards help correct for losses during extraction and analysis.
Enzymatic recycling assays provide a complementary approach for total glutathione. In these methods, glutathione reductase reduces oxidized glutathione while a thiol-reactive reagent, such as 5,5'-dithiobis(2-nitrobenzoic acid), produces a colored product. The reaction cycles between reduced and oxidized forms, amplifying the signal. Spectrophotometric or fluorometric detection can then estimate concentration. Distinguishing reduced glutathione from glutathione disulfide often requires separate aliquots, masking agents, or chromatographic separation, and the choice affects reported values.
In its reduced form, glutathione carries a sulfhydryl group that can donate electrons. This property lets it act as a major cellular antioxidant and redox buffer. Glutathione peroxidase uses it to reduce hydrogen peroxide and lipid peroxides, while glutathione reductase regenerates the reduced form using NADPH. The ratio of reduced glutathione to glutathione disulfide is widely used as an indicator of oxidative stress, though the ratio changes with compartment, cell type, and sample handling. Oxidized glutathione can also form mixed disulfides with proteins, affecting their activity.
Glutathione supports detoxification by conjugating reactive electrophiles through glutathione S-transferases. The resulting conjugates are processed and exported, often after further metabolism. It also stores cysteine, transports amino acids across membranes through the gamma-glutamyl cycle, and assists in the maturation of iron-sulfur clusters and some prostaglandins. In plants, animals, and many microbes, the molecule appears in similar roles, but concentrations vary enormously between tissues. Liver, kidney, and red blood cells tend to contain high amounts, while blood plasma contains much less.
Glutathione is a small tripeptide built from glutamate, cysteine, and glycine. The peptide bond between glutamate and cysteine uses the gamma-carboxyl group, a linkage that resists ordinary peptidases. Cells make it in two ATP-dependent steps: gamma-glutamylcysteine synthetase joins glutamate and cysteine, then glutathione synthetase adds glycine. The pathway is feedback-inhibited by glutathione itself, so intracellular levels tend to stay within a narrow range. Because cysteine is often limiting, sulfur amino acid supply influences how much glutathione a cell can produce.
The uprising may have been significant for the organisational development and strategy of the UDF. Over the course of the first year of the uprising, an internal debate was settled in favour of the front taking on a more expansive role, which would go beyond campaign-based protest and opposition to the Tricameral Parliament. Thus in 1985, the front declared its proposal to move "from mobilisation to organisation" through a programme to strengthen its organisational structures and discipline, including through increased accountability and representation for local affiliates. Similarly, at the grassroots level, by 1986 there was a movement in many black townships to re-establish political discipline, including by persuading students to return to school and subjecting them to the authority of strong local civic associations which included representations for elders. Moreover, historians of South Africa's trade union movement often view the Vaal uprising as an inflection point in the politicisation (or re-politicisation) of the major trade unions. According to Eddie Webster, the November 1984 stay-away marked "the beginning of united mass action between organised labour, students and community organisations". The Charterist Congress of South African Trade Unions was founded in late 1985 and went on to play a crucial role in the Mass Democratic Movement.
== Mechanism of catalysis == The molecular mechanism of O-linked N-acetylglucosamine transferase has not been extensively studied either, since there is not a confirmed crystal structure of the enzyme. A proposed mechanism by Lazarus et al. is supported by product inhibition patterns of UDP at saturating peptide conditions. This mechanism proceeds with starting materials Uridine diphosphate N-acetylglucosamine, and a peptide chain with a reactive serine or threonine hydroxyl group. The proposed reaction is an ordered sequential bi-bi mechanism.
=== Ending manufacture === Citing health concerns, several manufacturing companies have ended or stated that they plan to end the sale of PFAS or products that contain them. These companies include W. L. Gore & Associates (the maker of Gore-Tex), Patagonia, REI, H&M, and 3M. An alternative for some companies may have been to move production to countries such as Thailand and India, where there is less regulation.
Secondary structure prediction is a set of techniques in bioinformatics that aim to predict the local secondary structures of proteins based only on knowledge of their amino acid sequence. For proteins, a prediction consists of assigning regions of the amino acid sequence as likely alpha helices, beta strands (often termed extended conformations), or turns. The success of a prediction is determined by comparing it to the results of the DSSP algorithm (or similar e.g. STRIDE) applied to the crystal structure of the protein. Specialized algorithms have been developed for the detection of specific well-defined patterns such as transmembrane helices and coiled coils in proteins. The best modern methods of secondary structure prediction in proteins were claimed to reach 80% accuracy after using machine learning and sequence alignments; this high accuracy allows the use of the predictions as feature improving fold recognition and ab initio protein structure prediction, classification of structural motifs, and refinement of sequence alignments. The accuracy of current protein secondary structure prediction methods is assessed in weekly benchmarks such as LiveBench and EVA.
1961 Discovery by Leonard Hayflick of the limit of divisions for somatic cells, named the Hayflick limit. Hayflick found that normal human cells, extracted from fetus, are able to divide only about 50 times, after that they enter a senescence phase. 1969 Immunological theory of aging proposed by Roy Walford. 1974 Formation of the National Institute on Aging (NIA) – the aging of the population began to be perceived as a problem deserving state attention (and not as a problem of separate scientific societies). Since 1984, the NIA has begun to contribute in every way to the work of the National Archive of Computerized Data on Aging (NACDA). 1977 To explain aging, Thomas Kirkwood proposed the disposable soma theory. According to the theory, the organism has only a limited amount of resources that it has to allocate between different purposes (such as growth, reproduction, repair of damage). Aging occurs due to the limitation of resources that the body can afford to spend on repair. 1985 The discovery of telomerase, a ribonucleoprotein that is able to restore shortened telomeres. The discovery was made by Elizabeth Blackburn and Carol Greider. This research is based on the theoretical works of Alexey Olovnikov. The study of telomeres and telomerase required many more years and the work of many scientists around the world. For this work, in 2009, Elizabeth Blackburn, Carol Greider and Jack Szostak received the Nobel prize, in the same year Alexey Olovnikov was awarded the Demidov Prize.
Sources: en.wikipedia.org
trinucleotide repeat Any sequence in which an individual nucleotide triplet is repeated many times in tandem, whether in a gene or non-coding sequence. At most loci some degree of repetition is normal and harmless, but mutations which cause specific triplets (especially those of the form CnG) to increase in copy number above the normal range are highly unstable and responsible for a variety of genetic disorders.
Single-walled nanotubes are likely candidates for miniaturizing electronics. The most basic building block of these systems is an electric wire, and SWNTs with diameters of an order of a nanometre can be excellent conductors. One useful application of SWNTs is in the development of the first intermolecular field-effect transistors (FET). The first intermolecular logic gate using SWCNT FETs was made in 2001. A logic gate requires both a p-FET and an n-FET. Because SWNTs are p-FETs when exposed to oxygen and n-FETs otherwise, it is possible to expose half of an SWNT to oxygen and protect the other half from it. The resulting SWNT acts as a not logic gate with both p- and n-type FETs in the same molecule. Large quantities of pure CNTs can be made into a freestanding sheet or film by surface-engineered tape-casting (SETC) fabrication technique which is a scalable method to fabricate flexible and foldable sheets with superior properties. Another reported form factor is CNT fiber (a.k.a. filament) by wet spinning. The fiber is either directly spun from the synthesis pot or spun from pre-made dissolved CNTs. Individual fibers can be turned into a yarn. Apart from its strength and flexibility, the main advantage is making an electrically conducting yarn. The electronic properties of individual CNT fibers (i.e. bundle of individual CNT) are governed by the two-dimensional structure of CNTs. The fibers were measured to have a resistivity only one order of magnitude higher than metallic conductors at 300 K (27 °C; 80 °F).
Several artificial nucleobases have been synthesized, and successfully incorporated in the eight-base DNA analogue named Hachimoji DNA. Dubbed S, B, P, and Z, these artificial bases are capable of bonding with each other in a predictable way (S–B and P–Z), maintain the double helix structure of DNA, and be transcribed to RNA. Their existence could be seen as an indication that there is nothing special about the four natural nucleobases that evolved on Earth. On the other hand, DNA is tightly related to RNA which does not only act as a transcript of DNA but also performs as molecular machines many tasks in cells. For this purpose it has to fold into a structure. It has been shown that to allow to create all possible structures at least four bases are required for the corresponding RNA, while a higher number is also possible but this would be against the natural principle of least effort.
Glutamate synthase facilitates the ammonium assimilation pathway, which follows the enzymes, nitrite reductase and glutamine synthase. An ammonium produced by the nitrite reductase reaction will be incorporated into carbon skeleton backbone by glutamine synthase. Glutamine will be produced because of the introduction of ammonium in the carbon backbone, which can be converted into glutamate by glutamate synthase of another pathway. These processes are common in plant roots because if the nitrogen deficient conditions exist (with access to ammonium and nitrate ions), there will be a first priority of ammonium uptake. The reaction only proceeds in the direction of glutamic acid production: it converts one unit of glutamine and one 2-oxoglutarate into two units of product, using reduced nicotinamide adenine dinucleotide (NADH) as cofactor. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH2 group of donors with NAD+ or NADP+ as acceptor. This enzyme participates in glutamate metabolism and nitrogen assimilation. It uses the cofactor, flavin mononucleotide.
== History == In 1998, the University of Michigan formed a commission to create a vision for the future of the life sciences at the university. In response to the commission's recommendations, in 1999, the Regents of the University of Michigan unanimously approved the construction of the Life Sciences Institute, noting that "the creation of a life sciences institute will eliminate the structural barriers to a shared research and learning experience that will be valuable for both basic and applied research." Initial funding of $100 million was provided for the creation of wet lab space, in addition to the $130 million for the endowment and startup costs. The first faculty members moved into the building and opened their labs in September 2003, and the institute opened in May 2004. That same year, the institute's first two research cores opened, supporting high-throughput screening and structural biology research : the Center for Structural Biology and the Center for Chemical Genomics. The cryo-electron microscopy facility opened in 2009, expanding the institute's structural biology capabilities. In 2018, with support from the U-M Biosciences Initiative, the institute began expanding the cryo-EM program and also launched its Natural Products Discovery Core. In 2021, the building that houses the institute was renamed Mary Sue Coleman Hall, in honor of President Emerita Mary Sue Coleman.
Sources: en.wikipedia.org
== Signs and symptoms == Physical symptoms of CMRD involving the development and function of the gastrointestinal tract and nervous system typically manifest between infancy and adolescence. The symptoms of CmRD are similar to the physical symptoms of malnutrition, as the disease arises due to the poor absorption of lipids and fat-soluble nutrients such as vitamin E. For this reason, the disease is likely to be underdiagnosed by physicians. Fat-soluble nutrients are essential for growth, development, and normal bodily function. Vitamin E deficiency is especially serious, as the vitamin is necessary for proper neurological function and development. Without Vitamin E, neurons cannot operate correctly and signals from the brain are weakened. This leads to reduced muscle development and reduced muscle contraction. Symptoms that manifest in the GI tract are likely to be a consequence of both reduced absorption of fats and physiological stress imposed on enterocytes that can not shuttle fats into circulation. Additional symptoms that occur throughout the body can be attributed to the lack of sufficient lipid sources.
The Mareth Line constituted one of two fronts in the Tunisia Campaign, the second being to the north-west, where the British First Army and American II Corps, firmly established in formerly Vichy-held Morocco and Algeria following Operation Torch in November 1942, were gradually pushing the Axis forces under Hans-Jürgen von Arnim back towards Tunis. After von Arnim won a decisive victory over the Americans at the Battle of Sidi Bou Zid in mid-February 1943, destroying over 100 US tanks, the Eighteenth Army Group was formed under the British General Harold Alexander to co-ordinate the actions of the Allied forces on both Tunisian fronts. The Eighth Army under Montgomery spent February at Medinine in south-eastern Tunisia. Expecting an imminent attack by the Axis, the Eighth Army mustered every anti-tank gun it could from Egypt and Libya. The 102nd (Northumberland Hussars) Anti-Tank Regiment, including the Rhodesian Anti-Tank Battery under Major Savory, duly advanced west from Benghazi and reached the front on 5 March 1943. The Germans and Italians assaulted Medinine the next day, but failed to make much progress and abandoned their attack by the evening. The Rhodesian gunners, held in reserve, did not take part in the engagement but were attacked from the air. The Rhodesians of the KRRC, now under the 7th Motor Brigade, moved up from Libya during early March. No. 237 (Rhodesia) Squadron, which had spent 1942 and the first months of 1943 in Iran and Iraq, returned to North Africa the same month, with the future Prime Minister Ian Smith in its ranks as a Hurricane pilot.
Transient neonatal hypoglycemia Prematurity, intrauterine growth retardation, perinatal asphyxia Maternal hyperglycemia due to diabetes or iatrogenic glucose administration Sepsis Prolonged fasting (e.g., due to inadequate breast milk or condition interfering with feeding) Congenital hypopituitarism Congenital hyperinsulinism, several types, both transient and persistent Inborn errors of carbohydrate metabolism such as glycogen storage disease
== History == The older antihistaminic agent terfenadine was found to metabolize into the related carboxylic acid, fexofenadine. Fexofenadine was found to retain all of the biological activity of its parent while giving fewer adverse reactions in patients, so terfenadine was replaced in the market by its metabolite. Fexofenadine was originally synthesized in 1993 by Massachusetts-based biotechnology company Sepracor, which then sold the development rights to Hoechst Marion Roussel (now part of Sanofi-Aventis), and was later approved by the U.S. Food and Drug Administration (FDA) in 1996. Albany Molecular Research Inc. (AMRI) holds the patents to the intermediates and production of fexofenadine HCl, along with Roussel. Since that time, it has achieved blockbuster drug status with global sales of US$1.87B in 2004 (with $1.49B coming from the United States). AMRI received royalty payments from Aventis which enabled the growth of AMRI. In January 2011, the FDA approved over-the-counter sales of fexofenadine in the United States, and Sanofi Aventis' version became available in March 2011. In December 2020, the MHRA reclassified fexofenadine from prescription only to allow general sales in the United Kingdom.
Sources: en.wikipedia.org
It is a tripeptide rather than a full protein. Proteins generally contain many amino acids joined by alpha-peptide bonds, while glutathione has three residues and an unusual gamma-glutamyl linkage. That structure affects how enzymes recognize and break it down.
GSH is the reduced form with a free thiol group. GSSG is the oxidized disulfide dimer formed when two GSH molecules react. The GSH-to-GSSG ratio is used in research as one indicator of cellular redox conditions.
Yes, it is present in many animal and plant tissues, including meats, some vegetables, and fruits. Heat, storage, and processing can reduce its content, so measured amounts vary widely.
Glutathione is a sulfur-containing tripeptide made from glutamate, cysteine, and glycine. It is found in most cells and participates in redox balance and detoxification reactions.