Everything below concerns GSSG. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-10-04. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Synthesis occurs in two ATP-dependent steps. The enzyme glutamate-cysteine ligase joins glutamate and cysteine to form gamma-glutamylcysteine, and glutathione synthetase adds glycine. The first step is rate-limiting and is influenced by cysteine availability and feedback inhibition by GSH. Breakdown involves gamma-glutamyl transferase and subsequent peptidases, which release constituent amino acids for reuse. Because turnover differs among tissues, measurements from blood, plasma, and tissues are not directly interchangeable. Research continues to clarify how compartment-specific pools are regulated in health and disease.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine. It contains an unusual gamma-glutamyl bond between glutamate and cysteine, which resists cleavage by many peptidases. The reduced form, GSH, carries a thiol group on cysteine and is the dominant intracellular form in most cells. Its structure allows it to participate in redox reactions and to serve as a sulfur donor. The oxidized form, GSSG, consists of two GSH molecules joined by a disulfide bond.
In cells, glutathione helps maintain the reducing environment of the cytosol and supports enzymes that counteract reactive oxygen species. It acts as a cofactor for glutathione peroxidases, which reduce hydrogen peroxide and lipid peroxides, and for glutathione S-transferases, which conjugate electrophiles. The ratio of GSH to GSSG is often used as an indicator of oxidative stress, although the ratio can vary by compartment and cell type. Glutathione also stores cysteine, an amino acid that can be limiting for protein synthesis and antioxidant defense.
| 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 |
In February 2013, Essendon announced that they had asked the Australian Sports Anti-Doping Authority (ASADA) to investigate the supplements program that Dank had overseen at their club during the 2012 season. A former player, Kyle Reimers, had claimed that the players were asked to sign waivers and were injected with supplements that were "pushing the boundaries". Another former player, Mark McVeigh countered that the injections were only vitamins and all were completely legal and not on any World Anti-Doping Agency (WADA) banned substance list. Dank left Essendon at the end of the 2012 season, and high-performance manager Dean 'The Weapon' Robinson was suspended from the club after the announcement of the investigation. Stephen Dank controversially admitted to a Fairfax journalist that he had been using thymosin beta 4 on Essendon players. When journalist Nick McKenzie pointed out that that drug was prohibited by WADA under its S2 classification, Dank hesitated and then seemed extremely surprised: "Well, that must have just only come in this year and I will get someone to speak to ASADA about that. That's just mind-blowing." After 24 hours, Dank informed Fairfax media that he was actually really talking about thymomodulin which was a permitted substance. In 2015, the AFL Tribunal found him guilty of trafficking in a number of illicit supplements and banned him from any association with the AFL for life. Since most Australian sporting organisations honour sanctions imposed by other leagues, this had the effect of blackballing Dank from major Australian sport.
From the late 1960s to the early 1970s, with the rapid surge in recreational drug use in the U.S., the production of narcotics in Mexico, particularly marijuana, expanded exponentially, and Mexican criminals started to smuggle drugs on a major scale. During the 1960s and 1970s, Mexico participated in a series of U.S.-backed anti-narcotics initiatives, including Operation Intercept and Operation Condor. These operations were formally justified on the grounds of combating the cultivation of opium poppies and marijuana in Mexico's so-called "Golden Triangle" region, an area encompassing parts of the states of Sinaloa, Durango, and Chihuahua. As part of the campaign, the Mexican government deployed about 10,000 soldiers and police. The operation resulted in mass arrests, torture, and imprisonment of peasants who were often accused of aiding leftist insurgency groups, but no major traffickers were captured. Contemporary assessments deemed the initiatives a failure, citing their inability to curb narcotics production, enabling military corruption, and their record of human rights abuses in rural areas. As U.S. efforts in the war on drugs intensified, crackdowns in Florida and the Caribbean during the Miami drug war forced Colombian traffickers to develop new routes for smuggling cocaine into the United States. By the early 1980s, the Medellin Cartel and Cali Cartel oversaw production, while distribution increasingly relied on Mexican traffickers.
Distinguished for her research on the application of mass spectrometry to problems in chemical biology. She has used mass spectrometry to define the folding and binding of interacting proteins in large complexes. Most importantly, she has established that macromolecular complexes such as GroEL, ribosomes, and intact virus capsids can be generated in the gas phase and their electrospray mass spectra recorded. This work has demonstrated the power of mass spectrometry in studying very large complexes and allowed her to define changes in their conformation and the manner of their assembly. She was elected a Fellow of the Academy of Medical Sciences in 2009. In 2010, Robinson received the Davy Medal "for her ground-breaking and novel use of mass spectrometry for the characterisation of large protein complexes". In 2011, she was given the Interdisciplinary Prize by the Royal Society of Chemistry for "development of a new area of research, gas-phase structural biology, using highly refined mass spectrometry techniques", the Aston Medal, and the FEBS/EMBO Women in Science Award. She was appointed Dame Commander of the Order of the British Empire (DBE) in the 2013 New Year Honours for services to science and industry. She received the Thomson Medal Award in 2014.
=== Interaction with ethanol === Concurrent use with ethanol is contraindicated because fomepizole is known to prolong the half-life of ethanol via inhibiting its metabolism to acetaldehyde by alcohol dehydrogenase.
Politically, mercantilism was gradually replaced by liberal thoughts among the ruling elite. Following a monetary reform after the Napoleonic wars, the present Danish central bank Danmarks Nationalbank was founded in 1818. There exists national accounting data for Denmark from 1820 onwards thanks to the pioneering work of Danish economic historian Svend Aage Hansen. They find that there has been a substantial and permanent, though fluctuating, economic growth all the time since 1820. The period 1822–94 saw on average an annual growth in factor incomes of 2% (0.9% per capita) From around 1830 the agricultural sector experienced a major boom lasting several decades, producing and exporting grains, not least to Britain after 1846 when British grain import duties were abolished. When grain production became less profitable in the second half of the century, the Danish farmers made an impressive and uniquely successful change from vegetarian to animal production leading to a new boom period. Parallelly industrialization took off in Denmark from the 1870s. At the turn of the century industry (including artisanry) fed almost 30% of the population. During the 20th century agriculture slowly dwindled in importance relative to industry, but agricultural employment was only during the 1950s surpassed by industrial employment. The first half of the century was marked by the two world wars and the Great Depression during the 1930s.
Sources: en.wikipedia.org
=== Pyrolysis gas chromatography === Pyrolysis–gas chromatography–mass spectrometry is a method of chemical analysis in which the sample is heated to decomposition to produce smaller molecules that are separated by gas chromatography and detected using mass spectrometry. Pyrolysis is the thermal decomposition of materials in an inert atmosphere or a vacuum. The sample is put into direct contact with a platinum wire, or placed in a quartz sample tube, and rapidly heated to 600–1000 °C. Depending on the application even higher temperatures are used. Three different heating techniques are used in actual pyrolyzers: Isothermal furnace, inductive heating (Curie point filament), and resistive heating using platinum filaments. Large molecules cleave at their weakest points and produce smaller, more volatile fragments. These fragments can be separated by gas chromatography. Pyrolysis GC chromatograms are typically complex because a wide range of different decomposition products is formed. The data can either be used as fingerprints to prove material identity or the GC/MS data is used to identify individual fragments to obtain structural information. To increase the volatility of polar fragments, various methylating reagents can be added to a sample before pyrolysis. Besides the usage of dedicated pyrolyzers, pyrolysis GC of solid and liquid samples can be performed directly inside Programmable Temperature Vaporizer (PTV) injectors that provide quick heating (up to 30 °C/s) and high maximum temperatures of 600–650 °C. This is sufficient for some pyrolysis applications.
A nucleoside analog, blasticidin S resembles the nucleoside cytidine. The chemical structure consists of a cytosine molecule, linked to a glucuronic acid-derived ring, linked in turn to the peptide N-methyl β-arginine.
Like other cephalopods, octopuses have camera-like eyes. Colour vision appears to vary from species to species, for example, it is present in A. aegina but absent in O. vulgaris. Opsins in the skin respond to different wavelengths of light and help the animals choose a colouration that matches the surroundings and camouflages them; chromatophores in the skin can respond to light independently of the eyes. An alternative hypothesis is that cephalopod eyes in species that only have a single photoreceptor protein may use chromatic aberration to turn monochromatic vision into colour vision, though this lowers image quality. This would explain pupils shaped like the letter "U", the letter "W", or a dumbbell, as well as the need for colourful mating displays. Attached to the optic capsules are two organs called statocysts (sac-like structures containing a mineralised mass and sensitive hairs), that allow the octopus to sense the orientation of its body, relative to both gravity and time (angular acceleration). An autonomic response keeps the octopus's eyes oriented so that the pupil is always horizontal. Octopuses may also use the statocyst to hear. The common octopus can hear sounds between 400 Hz and 1000 Hz, and hears best at 600 Hz. Octopuses have an excellent somatosensory system. Their suction cups are equipped with chemoreceptors so they can taste what they touch. Octopus arms move easily because the sensors recognise octopus skin and prevent self-attachment. Octopuses appear to have poor proprioceptive sense and must see their arms to keep track of their position.
feline infectious enteritis virus (FIE) feline parvovirus (FPV or FP or "feline parvo") feline parvoviral enteritis It is sometimes confusingly referred to as "cat plague" and "feline distemper". In addition to members of the felid family, it can also affect other carnivorans (e.g. raccoon, mink).
Sources: en.wikipedia.org
=== Infantile-Onset (IOPD) === The infantile-onset (IOPD) form usually comes to medical attention within the first few months of life, either clinically or through newborn screening. The usual presenting features are cardiomyopathy, cardiomegaly, hypotonia, respiratory distress, muscle weakness, feeding difficulties, and failure to thrive. IOPD patients can be further classified by Cross-Reactive Immunological Material (CRIM) status which is an important predictor of clinical response. Patients that produce no GAA protein are referred to as CRIM negative. Therefore, they can develop highly sustained antibody titers for enzyme replacement therapy (ERT). Immunomodulation or immunotherapy is an effective treatment to prevent an immune response to ERT. The main clinical findings include floppy baby appearance, delayed motor milestones, and feeding difficulties. Moderate hepatomegaly may or may not be present. Facial features include macroglossia, hypernasal speech, hearing loss, and myopathic facies. Cardiopulmonary involvement is manifested by increased respiratory rate, use of accessory muscles for respiration, recurrent chest infections, decreased air entry in the left lower zone (due to cardiomegaly), arrhythmias, and evidence of heart failure. Before the development of a treatment, the median age at death in untreated cases was 8.7 months, usually due to cardiorespiratory failure. However, this outcome has drastically changed since enzyme replacement therapy became available, improving with early initiation of treatment.
==== 1947–1965 ==== The United States under the Truman administration leaned towards favouring India in the late-1940s as a consequence of most U.S. planners seeing India more valuable diplomatically than neighboring Pakistan. However, during the Cold War, Nehru's policy of neutrality was cumbersome to many American observers. American officials perceived India's policy of non-alignment negatively. Ambassador Henry F. Grady told then-Indian Prime Minister Jawaharlal Nehru that the United States did not consider neutrality to be an acceptable position. Grady told the State Department in December 1947 that he had informed Nehru "that this is a question that cannot be straddled and that India should get on the democratic side immediately". In 1948, Nehru rejected American suggestions for resolving the Kashmir crisis via third party mediation. Nehru's 1949 tour of the United States was "an undiplomatic disaster" that left bad feelings on both sides. Nehru and his top aide V. K. Krishna Menon discussed whether India should "align with United States 'somewhat' and build up our economic and military strength." The Truman administration was quite favorable and indicated it would give Nehru anything he asked for. Nehru refused, and thereby forfeited the chance for a gift of one million tons of wheat.
Beginning in the 11th century, European soldiers and knights relied on chain mail for protection of their bodies, and chain armor "shirts" with wide sleeves that hung to the elbow were common. However, it wasn't until the 12th century that chain mail shirts with longer, narrower sleeves began to be worn, and these on occasion had chain mail mittens or "muffs" resembling fingerless gloves and with a pocket for the thumb (though some of these did have complete fingers as well). These attached at the lower edge of the sleeve, and protected the wearer's hands from cuts and lacerations during combat but offered no protection against crushing blows. It wasn't until the early 14th century that armorers began to design fully articulated plate armor: along with this development of the use of plates as a means of protecting the body from blows was the development of hand protection in the form of gauntlets made of overlapping plates of steel. These were created both in the fingerless "mitten" style (which offered plate armor protection and allowed the fingers to share heat but limited the wearer's ability to move those fingers) as well as the fully fingered "glove" style (which though still ungainly and less comfortable in cold weather, permitted full use of all of the fingers). A variety of gauntlet called a "demi-gauntlet" or "demi-gaunt" also came into use around this time. A demi-gaunt is a type of plate armour gauntlet that only protects the back of the hand and the wrist: demi-gaunts are worn with gloves made from chain mail or padded leather.
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.
GSH is the reduced form with a free thiol group, while GSSG is the oxidized disulfide-linked dimer. Most assays distinguish the two because their balance reflects redox conditions. The names are not interchangeable.