The short version of LC-MS/MS fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-09-09. Anything still debated is marked as such rather than presented as settled.
Glutathione supports several cellular processes beyond direct antioxidant action. It serves as a cofactor for glutathione peroxidase and glutathione S-transferase enzymes, which reduce peroxides and conjugate electrophiles, respectively. The molecule also acts as a reservoir of cysteine, an amino acid that can limit protein synthesis and redox signaling. In human nutrition, oral glutathione is sold as a supplement, but how much intact glutathione reaches tissues after ingestion remains an active research question. Clinical claims about supplementation are not uniformly supported by controlled trials.
Glutathione is a small tripeptide built from glutamic acid, cysteine, and glycine. Its peptide bond between glutamate and cysteine involves the gamma-carboxyl group rather than the usual alpha-carboxyl group. This structure gives the molecule a reactive thiol on the cysteine residue. The reduced form, often abbreviated GSH, is the predominant intracellular species in many cell types. Because the thiol can donate electrons, glutathione participates in redox chemistry and in the conjugation of reactive molecules.
Quality control for glutathione measurements includes calibration with authenticated standards, internal standards where available, blank correction, and spike recovery checks. Because glutathione can form during sample processing or degrade before analysis, pre-analytical handling is a major source of variability. Interlaboratory comparisons often show differences in reported values due to method-specific calibration and detection principles. Interpretive thresholds are context-dependent, and no single reference range applies across all tissues or matrices. Researchers generally report both reduced and oxidized forms, along with the method and sample handling details.
Quantification of glutathione in biological or food samples commonly uses liquid chromatography coupled to ultraviolet, fluorescence, electrochemical, or mass spectrometric detection. Because the thiol group oxidizes readily, samples are often acidified or derivatized immediately after collection to stabilize reduced glutathione. Enzymatic recycling assays and colorimetric kits offer higher throughput but generally lower specificity than chromatographic methods. Mass spectrometry can distinguish glutathione from related thiols and allow simultaneous measurement of oxidized forms. Reported concentrations depend strongly on sample type, extraction procedure, and analytical platform.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C10H17N3O6S | Reduced form; oxidized dimer is C20H32N6O12S2 |
| Molar mass | 307.32 g/mol | For reduced glutathione (GSH) |
| Appearance | White crystalline powder | Typical laboratory and supplement-grade material |
| Solubility | Soluble in water | Poorly soluble in ethanol and other nonpolar solvents |
| Typical storage | -20 C, desiccated, protected from light | Reduced form can oxidize in solution |
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.
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.
Quantifying glutathione requires distinguishing GSH from GSSG and preventing oxidation during sample preparation. Common approaches include the enzymatic recycling assay, often called the Tietze method, which measures total glutathione after converting GSSG to GSH. HPLC with ultraviolet or fluorescence detection and LC-MS/MS can separate and quantify both forms, sometimes after derivatization of the thiol group. Blood, plasma, and tissue samples differ in matrix and baseline concentrations, so method validation must account for recovery, linearity, and interference. No single assay is universally standard.
Glutathione is most stable as a dry powder stored cool and dry, but its thiol group is readily oxidized in solution. Aqueous preparations at neutral or alkaline pH lose GSH faster because the thiolate form reacts with dissolved oxygen and metal ions. Acidic conditions, chelating agents, and oxygen exclusion can slow oxidation, while repeated freeze-thaw cycles promote degradation. Light exposure and trace metals also contribute to loss. Laboratories typically validate stability for their own matrices because degradation rates depend on pH, temperature, concentration, and container materials.
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.
Storage recommendations for glutathione reagents usually specify a cool, dry, dark environment because the thiol oxidizes in air and light. Solid material is often kept desiccated at low temperature, while solutions are prepared fresh or stored frozen in aliquots. Repeated freeze-thaw cycles can accelerate degradation, and metal ions can catalyze oxidation. Quality control may include purity assays, water content, and identity confirmation. Stability limits are method-specific, so a stated shelf life applies only to defined conditions and packaging.
Laboratory measurement of glutathione requires attention to oxidation before analysis. Blood, tissue, or cell samples can lose reduced glutathione as it converts to GSSG or forms mixed disulfides with proteins. Acid extraction, rapid freezing, and thiol-blocking reagents are common strategies to preserve the original distribution. Reported concentrations therefore depend on collection protocol, extraction method, and the time between sampling and analysis. Comparisons across studies are most reliable when these pre-analytical variables are described.
Common analytical approaches include enzymatic recycling assays, high-performance liquid chromatography, and mass spectrometry. The enzymatic recycling assay uses glutathione reductase and a colorimetric or fluorometric reagent to amplify signal, which gives good sensitivity for total glutathione. Chromatographic methods can separate GSH from GSSG and related thiols, while mass spectrometry offers structural confirmation and multiplexing. Each approach has different requirements for calibration, internal standards, and validation. No single method captures every form of glutathione in every matrix.
Oral fibromas are also termed irritation fibromas, focal fibrous hyperplasia, and traumatic fibromas. These lesions are nodules that occur on the buccal mucosa (i.e. mucous membranes lining the cheeks and back of the lips) or lateral tongue. They may be irritating or asymptomatic and are the most common tumor-like lesions in the oral cavity. Oral fibromas are not neoplasms; they are hyperplastic (i.e. overgrowth) reactions of fibrous tissue to local trauma or chronic irritation.
The relationships at the base of the animal tree have been debated. Other than Ctenophora, the Bilateria and Cnidaria are the only groups with symmetry, and other evidence shows they are closely related. In addition to sponges, Placozoa has no symmetry and was often considered a "missing link" between protists and multicellular animals. The presence of hox genes in Placozoa shows that they were once more complex. The Porifera (sponges) have long been assumed to be sister to the rest of the animals, but there is evidence that the Ctenophora may be in that position. Molecular phylogenetics has supported both the sponge-sister and ctenophore-sister hypotheses. In 2017, Roberto Feuda and colleagues, using amino acid differences, presented both, with the following cladogram for the sponge-sister view that they supported (their ctenophore-sister tree simply interchanging the places of ctenophores and sponges):
Curium was first intentionally synthesized, isolated and identified in 1944, at University of California, Berkeley, by Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso. In their experiments, they used a 60-inch (150 cm) cyclotron. Curium was chemically identified at the Metallurgical Laboratory (now Argonne National Laboratory), University of Chicago. It was the third transuranium element to be discovered even though it is the fourth in the series – the lighter element americium was still unknown. The sample was prepared as follows: first plutonium nitrate solution was coated on a platinum foil of ~0.5 cm2 area, the solution was evaporated and the residue was converted into plutonium(IV) oxide (PuO2) by annealing. Following cyclotron irradiation of the oxide, the coating was dissolved with nitric acid and then precipitated as the hydroxide using concentrated aqueous ammonia solution. The residue was dissolved in perchloric acid, and further separation was done by ion exchange to yield a certain isotope of curium. The separation of curium and americium was so painstaking that the Berkeley group initially called those elements pandemonium (from Greek for all demons or hell) and delirium (from Latin for madness). 242Cm was made in July–August 1944 by bombarding 239Pu with α-particles to produce curium with the release of a neutron:
==== Auditory system ==== Like all snakes, rattlesnakes lack external ear openings, and the structures of their middle ear are not as highly specialized as those of other vertebrates, such as mammals. Thus, their sense of hearing is not very effective, but they are capable of sensing vibrations in the ground, passed by the skeleton to the auditory nerve.
The main method of producing yogurt is through the lactic acid fermentation of milk with harmless bacteria. The primary bacteria used are typically Lactobacillus bulgaricus and Streptococcus thermophilus, and United States as well as European law requires all yogurts to contain these two cultures (though others may be added as probiotic cultures). These bacteria produce lactic acid in the milk culture, decreasing its pH and causing it to congeal. The bacteria also produce compounds that give yogurt its distinctive flavor. An additional effect of the lowered pH is the incompatibility of the acidic environment with many other types of harmful bacteria. For a probiotic yogurt, additional types of bacteria such as Lactobacillus acidophilus are also added to the culture.
Sources: en.wikipedia.org
=== Industrial === Major potassium chemicals are potassium hydroxide, potassium carbonate, potassium sulfate, and potassium chloride. Megatons of these compounds are produced annually. KOH is a strong base, which is used in industry to neutralize strong and weak acids, to control pH and to manufacture potassium salts. It is also used to saponify fats and oils, in industrial cleaners, and in hydrolysis reactions, for example of esters. Potassium nitrate (KNO3) or saltpeter is obtained from natural sources such as guano and evaporites or manufactured via the Haber process; it is the oxidant in gunpowder (black powder) and an important agricultural fertilizer. Potassium cyanide (KCN) is used industrially to dissolve copper and precious metals, in particular silver and gold, by forming complexes. Its applications include gold mining, electroplating, and electroforming of these metals; it is also used in organic synthesis to make nitriles. Potassium carbonate (K2CO3 or potash) is used in the manufacture of glass, soap, color TV tubes, fluorescent lamps, textile dyes and pigments. Potassium permanganate (KMnO4) is an oxidizing, bleaching and purification substance and is used for production of saccharin. Potassium chlorate (KClO3) is added to matches and explosives. Potassium bromide (KBr) was formerly used as a sedative and in photography.
Rather than finding homologous proteins from different species, a new Tag/Catcher pair was developed from SpyTag/SpyCatcher with minimal mutations. SpyTag I3W (AW) reacts with SpyCatcher F77V, F94A (BVA) but minimally with SpyCatcher, whereas SpyCatcher F77V, F94A can react with both SpyTag I3W and SpyTag. However, the cross-reactivity of SpyCatcher F77V, F94A with both SpyTag versions may limit its utility as a new Tag/Catcher pair. A different chemistry can be exploited for protein ligation: the discovery of an intramolecular ester bond formation in Clostridium perfringens cell-surface adhesin protein Cpe0147 led to the development of another Tag/Catcher pair with Cpe0147565–587 as the Tag and Cpe0147439–563 as the Catcher. The ester bond formed between Thr-Gln is irreversible, however by mutating the Thr to Ser, the Ser-Gln ester bond is reversible with a change of pH.
=== Importance === Calciseptine has been shown to specifically inhibit the L-type voltage-gated Ca2+ channels and was the first natural polypeptide discovered with this property. Specific polypeptide inhibitors of voltage-sensitive channels are important tools in research, and were already known for voltage-sensitive Na+ channels, both voltage-sensitive and Ca2+-activated K+ channels, and for N-type Ca2+-channels. Before calciseptine was sequenced and shown to be a specific L-type calcium channel inhibitor, no specific polypeptide inhibitors were known for this type of voltage-gated channels. Specific blockers of the L-type channel were small organic molecules like 1,4-dihydropyridines. It was suggested that polypeptide inhibitors could be found in snake venoms. Calciseptine confirmed this as it was shown to not only block the L-type channels specifically, but also to do this in exactly the same spot as the 1,4-dihydropyridines. After calciseptine, other polypeptides specifically blocking the L-type channels were found as well: FS2, C10S2C2 and S4C8.
== Structure == In humans, granzyme B is encoded by GZMB on chromosome 14q11.2, which is 3.2kb long and consists of 5 exons. It is one of the most abundant granzymes of which there are 5 in humans and 10 in mice. Granzyme B is thought to have evolved from a granzyme H related precursor and is more effective at lower concentrations than the other granzymes. The enzyme is initially in an inactive precursor zymogen form, with an additional amino terminal peptide sequence. This sequence can be cleaved by cathepsin C, removing 2 amino acids. Cathepsin H has also been reported to activate granzyme B. Granzyme B's structure consists of two six-stranded β sheets with three trans domain segments. In the granules of cytotoxic lymphocytes the enzyme can exist in two glycosylated forms. The high mannose form weighs 32kDa and the complex form, 35kDa. Granzyme B contains the catalytic triad histidine-aspartic acid-serine in its active site and preferentially cleaves after an aspartic acid residue situated in the P1 position. The aspartic acid residue to be cleaved associates with an arginine residue in the enzyme's binding pocket. Granzyme B is active at a neutral pH and is therefore inactive in the acidic CTL granules. The enzyme is also rendered inactive when bound by serglycin in the granules to avoid apoptosis triggering inside the cytotoxic T cells themselves.
Sources: en.wikipedia.org
=== Enzymatic hydrolysis === For the production process of enzymatic HVP, enzymes are used to break down the proteins. To break down the protein to amino acids, proteases are added to the mixture of defatted protein and water. Due to the sensitivity of enzymes to a specific pH, either an acid or a base is added to match the optimum pH. Depending on the activity of the enzymes, up to 24 hours are needed to break down the proteins. The mixture is heated to inactivate the enzymes and then filtered to remove the insoluble carbohydrates (humin). Since no salt is formed during the production process, manufacturers may add salt to eHVP preparations to extend shelf life or to provide a product similar to conventional aHVP. A vendor source states that salt is conventionally added before eHVP production to control microbial growth. With acid-tolerant enzymes, some of the salt can be replaced with a small amount of an acid (patent literature mentioning the acid-tolerant enzyme suggests a reaction pH of 4) to reduce sodium content.
Ethanol does induce non-lamellar phases (non-bilayer) but this process is concentration-dependent. On average the bilayers is preserved at approximately less than 10 mol%. Ethanol prefers to bond in the hydrophilic region near phosphate groups which could be contributed to its amphiphilic character. The effects of ethanol can be reversed or hindered in the presence of cholesterol (sterol compounds) It may be necessary to perform a future study to compare the maximum amount of cholesterol (30 mol%) obtained in the NNR study to varied concentrations of ethanol as depicted in the AMDS study to see if ethanol is still hindered in the presence of sterol compounds.
=== 1988 === 11 February Running to Time, about the new InterCity 225; the National Express Coaches Rapide service; the project team of the Intercity 225, with project director Mike Rollin, and Mike Newman of GEC; the 225 train had to be delivered on 14 February 1988, with an operational life of thirty years; the InterCity 125 was not intended to have been primarily developed - in a board meeting, the commercial directors were not technologically knowledgeable of trains, and asked about alternatives, to be told by an engineering director that a 125 mph diesel train could be developed in two years, so the HST began at that meeting; the British Rail APT-E prototype, powered by the Leyland 2S/350 gas turbine; in 1974 BR commissioned the APT-P, which had ten years of development, due to the active tilting suspension; the 225 train was possibly to enter service on the UK's only large electrified line, the West Coast Main Line, but the much-straighter and faster East Coast Main Line was being electrified, so BR decided to implement the 225 train on the ECML instead; Crewe railway station, which opened in 1837, and where trains were first built nearby in 1843; Steve Corfield, of Crewe Works; the unsprung mass of a train, and Cardan shafts; Roger Ford of Modern Railways; John Prideaux, director of InterCity; David Carter of DCA in Warwick, who designed the livery; the Modernisation Plan was published in December 1954, which had advocated the electrification of the ECML, and the phasing-out of steam travel; the late-1980s ECML electrification had cost BR £350m - it was not government-funded, with 2,800 miles of copper wire, and 33,000 support masts, overseen by Don Heath; all of the improvements in the UK were on old lines of track, but France and Germany had built entire new electrified lines - the TGV was planned from the mid-1960s; G. Freeman Allen of Jane's World Railways; the 225 train underframe being built at Crewe Works; GEC Traction at Preston, Lancashire, Al Reed, the separately excited (Armature Controlled DC Motor) brushed DC electric motor, and Gerald West; the right-angle gearboxes were built by David Brown Ltd and Voith of Heidenheim an der Brenz in southern Germany; Eric Black of Metro-Cammell in Washwood Heath; the ST41 bogies were made by SIG Combibloc Group of Neuhausen am Rheinfall in Switzerland. Narrated by Robin Ellis, produced by Patrick Uden, directed by Paul Fabricius, made by Uden Associates. 12 February Playing with Fire 17 July The Air Fix!, about aviation safety; a television adaptation of a black comedy theatre production by 35-year-old James Castle, dressed as an airline pilot, largely featuring Turkish Airlines Flight 981, the Ermenonville air disaster, in France on 3 March 1974, to this day the worst airliner crash, without any survivors, with 177 British people killed, when a cargo door ruptured, and the subsequent enquiry led to a cover up by the airline and aviation authority; the DC10 had known design failings in its fuselage, and its cargo door design was known to be faulty by the aircraft manufacturer; the American Airlines Flight 96 crash had happened on 12 June 1972, involving a design failure of the cargo door, but the FAA nonetheless gave the DC-10 a certificate of airworthiness; the DC10 had been rushed into service; James Castle accused the aircraft industry of callous negligence; James Castle had been a British Airways aircraft maintenance technician from 1969 to 1977 at Heathrow Airport; he listed the numbers of children that lost one or both parents in the crash, and the numbers of women who were widowed; the theatre production had been going since December 1986, directed by Caroline Noh Narrated by James Castle, produced by Ben Gooder, made by Uden Associates 24 July Nic's Boat, about Nic Bailey, a 37-year-old architect with Foster and Partners; he designed a 40-ft trimaran, called MTC, for the Carlsberg Single-Handed Trans-Atlantic Race on 5 June 1988; he had helped to design the 1978 Sainsbury Centre for Visual Arts in Norwich and the Renault Centre in Swindon; boat builder Spud Rowsell in Exmouth, with Phil Morrison; the hull cost £46,000, and the rigging cost £46,000; the mast and rigging were fitted at Topsham, Devon; Robin Knox-Johnston; French yacht designer Bruno Fehrenbach; he sailed the Atlantic between the Rhumb Line Route and the Great Circle Route; some yachts made the journey to Newport, Rhode Island in ten days; the yacht mast was constructed by Proctor South West. Produced by Michael Wills, directed by Bob Bee, made by Juniper Productions 31 July The Living Dead 7 August Zen and the Art of TV Manufacture, a Panasonic TV factory in South Wales; in 1933 the company founder Kōnosuke Matsushita established seven guiding commercial principles; the Fidelity TV factory in west London was given one year - 1988 - to turn its fortunes around or be closed; the factory's closure was announced to the workforce on 25 January 1988, with the site closing at the end of July 1988; Amstrad bought the Fidelity name in May 1988. Narrated by Alan Howard, directed by Patrick Uden, produced by Michael Proudfoot, made by Uden Associates 14 August How Good Is Soviet Science?, about the political inhibition of Soviet technology in the 1980s; in many ways the Soviet Union in 1987 was a backward and underdeveloped nation, with food queues; the Soviet system didn't respond to changes in demand - everything was planned years in advance; physicist Alexander Prokhorov, who won the Nobel Prize for Physics in 1964; Russians were proud of mathematicians Pafnuty Chebyshev and Nikolai Lobachevsky; large government centrally planned projects were compatible with the communist system, notably its space programme; by the 1970s, the Russians realised that they were some distance behind other countries, such as in disciplines of computing and genetics; science teaching was emphasised at Soviet schools, and English was well taught as well; after secondary schools, half went into science; theoretical science was where Soviet teaching excelled, such as at the Steklov Institute of Mathematics; Yuri Ovchinnikov wanted to improve Soviet science; in the early 1950s, the Soviet Union tried to ignore the findings of genetics, through the work of Trofim Lysenko, who claimed that genetics was anti-communist, known as Lysenkoism leading to many scientists being imprisoned and executed; in the 1960s, a set of large biological research centres were built at Pushchino; one of the most well-built research institutes was the Shemyakin Institute of Bioorganic Chemistry, for biotechnology; Stalin did not like computer science, and it was largely banned until 1958; the Soviets were always years behind in computer science; the first recognisable transistor Soviet computer was the BESM-6 in the 1960s; later computers were the ES EVM series, copied from the IBM System/360; the Akademgorodok (Academic City) in Novosibirsk; the Institute of Automation and Electrometry researched optical memory on holographic slides to and much work on lasers; collaboration between Soviet research and Soviet industry was long-winded, maybe almost impossible - the centrally planned Soviet industry could not sufficiently adapt for short-term changes, as it had to be monotonously planned years in advance, for mass production; Soviet government research was perhaps excellent nonetheless; not many Soviet scientists could travel to international conferences; dissemination of current worldwide science was limited throughout the Soviet Union, due to widespread government restrictions; Suite No. 2 in B minor, BWV 1067. Narrated by US technology historian Loren Graham, produced by Chris Durlacher, directed by Martin Smith, made by Uden Associates, NDR and WGBH. Shown on Nova on 17 November 1987 and 22 March 1988 21 August Toys for the Boys, about the Williams racing team; Graham Hill and Jim Clark in 1967; Tomorrow's World in 1967, narrated by Derek Cooper; journalist Peter Windsor of Williams; aerodynamicist Frank Dernie, head of research at Williams; Keith Botsford, motor racing editor of the Sunday Times; the German racing manager Alfred Neubauer, in the late 1930s; there were 18 F1 teams, with 7 being British; Mobil Oil paid Williams £2.5m for advertising on the cars of Nigel Mansell and Riccardo Patrese; the Williams FW11; racing driver Howden Ganley; part of a BBC Horizon documentary broadcast on 9 March 1981, featuring the Williams FW07, and likewise narrated by Martin Jarvis and produced by Patrick Uden; engineering director Sir Patrick Head; Bach Mass in B minor; Mike Hawthorn, was killed on a public road, the A3 Guildford bypass, in his Jaguar Mark 1 on 22 January 1959; Canadian Gilles Villeneuve was thrown from his Ferrari, when qualifying for the 1982 Belgian Grand Prix; Swedish Ronnie Peterson, died after an accident on the start line at the 1978 Italian Grand Prix; Italian Elio de Angelis was killed in May 1986 at the Circuit Paul Ricard in south-east France; British Piers Courage burned to death at the 1970 Dutch Grand Prix; Jim Clark hit a tree on 7 April 1968 at the 1968 Deutschland Trophäe in the north-west of Baden-Württemberg; German Jochen Rindt was killed at the 1970 Italian Grand Prix after winning the championship in the same year, which was awarded posthumously; Bach Mass in B minor; Frank Williams had a crash on 8 March 1986 in the south of France, with Peter Windsor, in a Ford Sierra, making him quadraplegic; the Williams wind tunnel; Alan Jones waving the British flag at the 1980 Grand Prix; the 1988 season Williams car had a Judd V8 engine; the closing fanfare of Les préludes by Liszt; the documentary ends with German military march Prussia's Glory. Narrated by Martin Jarvis, produced by Patrick Uden, made by Uden Associates 28 August Cold Spring, Morning Sun, about atomic physicist Joan Hinton and her husband Erwin Engst. Joan's mother was teacher Carmelita Hinton. Joan worked on the top secret Manhattan Project at Los Alamos in 1944 which produced the atomic bombs that were dropped on Hiroshima and Hagasaki in the summer of 1945. After the war, Joan, her brother Bill, and her husband Erwin (Sid) Engst travelled to China to join Mao Ze Dong and the cultural revolution. Over the next five decades, Joan and Sid became pioneers in Chinese agricultural science and technology. Narrated by Liza Goddard, written, produced and directed by Chris Haws, Made by InCA. 18 September Taking the Tunnel, who would be travelling through the Channel Tunnel; the tunnel would open in May 1993; Colin Kirkland, technical director of Eurotunnel; Roger Vickerman of the University of Kent; historian Corelli Barnett, and how France and Germany spent money after the war improving rail infrastructure; journalist Kathy Watson; a working model was built of the two Channel rail terminals; 90% of the tunnel went through chalk; the French end was built much more water-tight than the English end, due to the worse geology; the tunnel was around one mile long at the English end, to meet the French side in 1990; the Single Market would stop duty free sales on the Channel ferries; the former Night Ferry across the Channel, which operated until 30 October 1980; TGV Est would connect Bordeaux, and TGV Nord would connect to Germany, the Netherlands, with a spur to the new tunnel; Richard D. North; tolls on the autoroutes discouraged local traffic, which slowed down British motorways; Daniel Ghouzi of Transmanche; Martin Simmons of Kent County Council; A292 junction of M20; Corelli Barnett believed that the British civil service was best at fudging, whereas the French civil service had been trained differently at the French grandes ecoles; a VTG ship from Dover to Dieppe carried trains; freight journeys over 250 miles were most cost effective by rail, but did lack logistical flexibility at either end; Michael Barclay of Tiphook Rail; a distribution centre in Paddock Wood in Kent, built by the Spanish Transfesa; UIC gauge was the main European gauge for freight; Artura Boix of Transfesa; Richard Hope of Railway Gazette; British trains had a 25 tonne axle weight, more than the European 22 tonnes; early plans for the new Eurostar trains, which would be dual voltage for travelling in England and France; rail writer Geoffrey Freeman Allen; the French trains would leave from the Gard du Nord; customs checks would be at the British end in London, but not in France; British Rail planned a high speed line across Kent to open in 1998 from King's Cross, but it would not open until September 2003, and to London in November 2007; Roger Ford of Modern Railways. Narrated by Geoffrey Palmer, produced by Patrick Uden, directed by Paul Fabricius, made by Uden Associates 25 September Road Test about road transport in the UK; there were two million vehicles in the UK in 1930; a test drive would be conducted from The Point, Milton Keynes at 8.30am to Maidstone, by different routes - Mike McDonald of the University of Southampton and Margaret Bell of the University of Nottingham in a Volvo 850 would go across London, and Peter Bonsall and Howard Kirby of the University of Leeds in a Volkswagen Passat B3, would follow the M25 to the north of London, George Hazel of Napier College and John Wootten in a Ford Granada would follow the M25 south of London, and Martin J. H. Mogridge would take the train on the new Thameslink from Bedford railway station via Blackfriars Railway Bridge; the test would be directed from the Road Traffic Research Centre at Middlesex Polytechnic, with Chris Wright, Peter Hills from Newcastle University, and psychologist Ivan Brown from the Applied Psychology Unit (MRC Cognition and Brain Sciences Unit) in Cambridge; variable-message signs (VMS) on the M6; before joining the M25, the vehicles had an average speed of 50 mph; the early plans in the 1940s for the M25, which the M25 to the south and west of London, now largely follows; when the M25 needed to be built, in the 1960s, many environmental objections had arisen for it to be built; Russ Kane in Capital Radio's Flying Eye; David Marsh at the AA Roadwatch studio in north London; the ramp meter, installed on the M6 by John Wootten; all of London's traffic lights were controlled from a computer centre in Westminster, with software (Split Cycle Offset Optimisation Technique) developed by Dennis Robertson; the Volvo 850 enters London along the Edgware Road and Park Lane to Hyde Park Corner; the prototype Autoguide system invented by Ian Catling; automatic vehicle identification (AVI) and piezoelectric strips developed at the University of Nottingham Department of Civil Engineering, and tested by Peter Davies on the Nottingham ring road, next to the QMC; the Volkswagen Passat arrives first at the Great Danes Hotel, making the 107 miles in two hours seventeen minutes, an average speed of 47 mph; the route south of London - 119 miles, also has a 47 mph average speed; the 96-mile rail journey had an average speed of 35 mph; the programme content would be copied by Top Gear fifteen years later. Narrated by Martin Jarvis, produced by David Sharp, directed by Mike Tomlinson, made by Orlando Productions 9 October Look, No Hands! about technology outpacing human knowledge; Hubert Dreyfus of University of California, Berkeley; Martin Corbett, industrial psychologist at the University of Warwick; work by Mike Cooley, and systems design; mechanical engineer Frederick Winslow Taylor and his meticulous improvements to industrial methods, in his book The Principles of Scientific Management; John Harris, manager of the Rolls-Royce helicopter engine plant at Leavesden, Hertfordshire; perhaps automation in engineering manufacturing processes could perhaps add or enhance, rather than totally replace, which required and produced less directly competent workers. Produced by Debra Hauer, directed by Christopher Rawlence, made by Hauer Rawlence Productions 16 October Spytech, John Pike of the Federation of American Scientists and how the Space Shuttle was built mostly for low Earth orbit reconnaissance satellites; but the Titan 34D was also available for many spy satellite launches; Christopher Andrew of the University of Cambridge; Harry Rositzke of the CIA, and the disastrous Operation Red Sox, from 1949 to 1953; William Colby, Director from 1973 to 1976 of the CIA, and how spying methods that worked in Germany during World War II were simply hopeless in a possibly more bizarre culture of communist eastern Europe in the early 1950s, so Ferret missions by B-29 aircraft over the border were attempted instead, but many were shot down; the Americans decided to go for high-altitude reconnaissance; on 1 May 1960, an aircraft photographing a missile construction factory, pilot was sentenced to 10 years, but released after two years in exchange for Rudolf Abel; H. Keith Melton and notorious improvised technology of the KGB; the Russian defector Stanislav Levchenko; the burst transmission method; camera lenses for spy satellites made by Itek; the Space Shuttle was built to maintain and repair the Key Hole set of spy satellites, such as KH-11 KENNEN, launched by the National Reconnaissance Office (NRO) in 1976, and introduced digital photography, and EOSAT and its Landsat program; Jeffrey T. Richelson, a writer on national security; Major-General George Keegan of the Twenty-Fifth Air Force described how the Soviet Union got to know when spy satellites would be overhead, and would hide anything sensitive; listening satellites sent their data to the NSA at Fort Meade in Maryland, such as data from Magnum, launched by the secret STS-51-C mission in January 1985; Paul Bracken and all-source intelligence fusion; Soviet intelligence in the US was quite widespread, with up to 800 spies operating out of Soviet trade missions, and operated much more widespread than the US had attempted; the new KH-12 satellite, that launched in November 1992, could see through clouds. Narrated by Mike Short, produced by Claudia Milne, made by Twenty Twenty 23 October Bamboo, the importance of bamboo to the Chinese economy; Prof Hsiung Wenyue of the Bamboo Research Centre of Nanjing Forestry University; bamboo structures do not collapse in high winds; over a thousand species of bamboo; bamboo dies out for ten years, then grows again; only 15% of China can be cultivated; bamboo can grow four feet in 24 hours, it is the fastest growing plant; bamboo has a tensile strength twice as much as timber; hospitals in China worked with herbal remedies; bamboo traders had quotas set by the Chinese government; bamboo shoots were mostly exported to Japan; growing bamboo helped soil structure; the Chinese government encouraged the growing of bamboo, as an alternative to timber. Narrated by Jenny Agutter, produced by Michael Blakstad, directed by Patrick Fleming, made by Workhouse Productions, made in cooperation with China Central Television 30 October Heavy Metal, chemist Neil Ward of the University of Surrey, who found abnormal pregnancies; medical doctor Robin Russell-Jones of the Campaign for Lead Free Air; environmental chemist Brian Davies of the University of Bradford; footage from the 1971 BBC A Public Poison, with chemist Derek Bryce-Smith, and Patrick Lawther of St Bartholomew's Hospital; Gloria all'Egitto from Aida by Giuseppe Verdi, with the assembly line of the Rover 800; Robin Brundle; Eric Fountain of Vauxhall Motors; Ojos Criollos by Louis Moreau Gottschalk. Narrated by Catherine Robins, produced by Michael Blakstad, made by Workhouse Productions 13 November Free Flight, about gliding, with Derek Piggott in a Rolladen-Schneider LS4 at Booker Gliding Centre in Buckinghamshire; in the UK there were about 350,000 flights and 2 deaths each year; a Schleicher ASW 24 in a wind tunnel with Loek Boermans at TU Delft Faculty of Aerospace Engineering in the Netherlands; the Schleicher ASH 25 with glider pilot John Jeffries at London Gliding Club west of Dunstable; at Wasserkuppe, a 3,000 ft mountain in the east of Hesse in the centre of Germany is where gliding mostly developed in the 1920s by the Deutsche Forschungsanstalt für Segelflug, due to German powered-aircraft manufacturing being legally restricted; nearby at Poppenhausen, Hesse is Alexander Schleicher GmbH & Co, with designer Gerhard Waibel, where gliders had wings made from carbon fibre, and covered in kevlar for torsional stiffness; the first glider of a contemporary design was the Akaflieg Stuttgart fs24 in 1951. Narrated by Robert Gary 20 November Chaos, Tim Palmer of the ECMWF; mathematician Robert L. Devaney; German mathematician Heinz-Otto Peitgen and fractal geometry; strange attractors in dynamical systems, such as weather systems; David Rand of the University of Warwick, and period-doubling bifurcation, discovered in 1975 by mathematician Mitchell Feigenbaum discovered; fractal landscapes; British mathematician Michael Barnsley, and affine transformations, which are applied to digital image processing; the chaos game; Soviet physicist Lev Landau; physicist Harry Swinney of the University of Texas; economist James B. Ramsey; Ian Stewart of the University of Warwick, and the unpredictable rotation of Hyperion. Written, produced and directed by Chris Haws, the programme was made by Independent Communications Associates (InCA). In 1989, it won the SciTech Award for best scientific documentary. 27 November The Art of Deception, about camouflage, deception, decoys and stealth. The Northrop Grumman B-2 Spirit was first displayed on Tuesday 22 November 1988, just five days before the programme was aired. Featured interviewees include: Richard P. Hallion of Wright-Patterson Air Force Base; Peter Varnish of the Admiralty Research Establishment at Funtington in West Sussex; defence writer Antony Preston; Roy Behrens of the Art Academy of Cincinnati; Lt Col Chris Nash of Surveillance, Target Acquisition, Night Observation and Counter-surveillance (STANOC); Major William Marshak of the AAMRL - now the 711th Human Performance Wing; Captain Brian Perowne, commanding officer of HMS Brazen (F91); aviation writer Bill Sweetman, and Commander Patrick Walker, commanding officer of HMS Trafalgar (S107) a Royal Navy hunter-killer submarine; John Hall of the Admiralty Research Establishment (former Admiralty Experiment Works) at Haslar. Narrated by Nick Chilvers, Written, produced and directed by Chris Haws, made by InCA and WGBH Boston
Sources: en.wikipedia.org
It is a tripeptide of glutamic acid, cysteine, and glycine. The linkage between glutamate and cysteine uses the gamma-carboxyl group, which is unusual for peptides.
GSH is the reduced form with a free thiol group. GSSG is the oxidized dimer formed when two GSH molecules join by a disulfide bond.
It is synthesized inside cells and is not classified as an essential dietary nutrient for most people. Dietary and supplemental sources are studied, but direct requirements are not established in the same way as for vitamins.
Acidification lowers pH and helps prevent oxidation of the thiol group during extraction and storage. It can also precipitate proteins and stabilize the reduced form before analysis.