sample preparation raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-09-17 and is reviewed periodically as new material appears.
Quality control for glutathione materials checks identity, assay, purity, water content, and disulfide content. Commercial products vary from research-grade powder to dietary supplements, and labels may not distinguish reduced from oxidized forms. In the United States, oral glutathione is commonly sold as a dietary supplement rather than an approved drug, while injectable forms fall under different rules and may require a prescription. Regulatory status differs by country. Analytical certificates, when available, help verify what a material contains, but independent testing remains important for interpretation.
Laboratory measurement of glutathione typically starts with rapid acid extraction to prevent oxidation and enzymatic degradation. Common methods include enzymatic recycling assays, high-performance liquid chromatography, and liquid chromatography coupled with mass spectrometry. The recycling assay uses glutathione reductase and a thiol-reactive colorimetric or fluorescent reagent, measuring total glutathione after converting disulfide forms. Chromatographic methods can separate reduced and oxidized forms, which helps when the redox ratio is the target. Choice of method affects sensitivity, specificity, and the amount of sample needed.
Interpreting glutathione measurements requires attention to pre-analytical variables. The GSSG concentration in a sample can rise artificially during storage or processing, making the GSH/GSSG ratio unreliable if not controlled. Reference ranges vary by specimen type, assay, and population, so comparisons across studies are difficult. Plasma glutathione is low and sensitive to hemolysis, while whole blood reflects primarily erythrocyte content. Many studies measure total glutathione rather than the reduced and oxidized forms separately, which limits conclusions about redox status.
Accurate measurement of glutathione begins with careful sample handling. Because GSH oxidizes rapidly to GSSG, samples must be processed quickly or frozen immediately. Acid precipitation with metaphosphoric acid or perchloric acid is common; it lowers pH, precipitates proteins, and helps preserve the reduced form. Chelating agents such as EDTA can limit metal-catalyzed oxidation. For whole blood, hemolysis releases glutathione from erythrocytes, so plasma and serum values differ substantially from whole blood values.
| Property | Value | Notes |
|---|---|---|
| Recommended storage | −20 °C, desiccated | For dry powder; limit light and air exposure |
| Solution stability | Hours to days at neutral pH | Faster loss at warm, alkaline, or oxygen-rich conditions |
| Routine measurement | LC-MS/MS or HPLC | Enzymatic recycling assays measure total glutathione |
| Thiol pKa | About 8.7 | The thiolate form reacts with oxidants and electrophiles |
| Common abbreviations | GSH and GSSG | GSSG is the disulfide-linked dimer |
Quality control for glutathione focuses on identity, purity, and oxidation state. Certificates of analysis may report assay value, water content, and the presence of GSSG or other impurities. Chromatographic purity is often expressed as a percentage of peak area. Reference standards help laboratories compare results across instruments and batches. Because glutathione is a small, polar molecule, separation from cysteine, gamma-glutamylcysteine, and related thiols can be challenging. Verification often combines more than one analytical technique.
Measuring glutathione requires attention to sample preparation because the molecule oxidizes readily. Blood, tissue, and cell samples are often treated with acid to precipitate proteins and stabilize the thiol. Without such steps, GSH can convert to GSSG or form mixed disulfides during storage. Analytical methods include spectrophotometric assays, high-performance liquid chromatography, and mass spectrometry. Each approach has different sensitivity, specificity, and susceptibility to interference from related compounds in complex matrices.
For solid glutathione, storage conditions affect shelf life. The reduced form is typically kept cool, dry, and protected from air and light. Moisture can promote oxidation, while elevated temperatures accelerate degradation. Suppliers often specify storage at or below freezing, sometimes under inert gas. Solutions are less stable than powders and may require preparation shortly before use. Buffers and chelating agents can slow oxidation, but they do not eliminate it. Published stability data vary with matrix, pH, and container.
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.
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 is synthesized in two ATP-dependent steps. First, gamma-glutamylcysteine synthetase links glutamate and cysteine; second, glutathione synthetase adds glycine to form the complete tripeptide. The pathway is feedback-inhibited by GSH itself, which helps maintain steady intracellular levels. Tissues vary widely in glutathione content, with the liver typically containing the highest concentrations, followed by the kidneys, lungs, and erythrocytes. Because cysteine is often limiting, its availability influences synthesis rates, and regulation of this pathway varies by cell type.
Glutathione serves as a cofactor for several enzymes, including glutathione peroxidase and glutathione S-transferase. These enzymes help reduce hydrogen peroxide and lipid peroxides, and they conjugate reactive electrophiles for excretion. The molecule also acts as a reservoir for cysteine, an amino acid that is prone to oxidation. In addition, glutathione participates in the metabolism of nitric oxide, leukotrienes, and prostaglandins. Its roles extend to cell signaling, apoptosis, and the regulation of protein function through S-glutathionylation.
Glutathione is a tripeptide composed of glutamate, cysteine, and glycine, and it is the most abundant non-protein thiol in most living cells. The reduced form, GSH, carries a sulfhydryl group that can donate electrons, while the oxidized form, GSSG, forms when two GSH molecules link via a disulfide bond. The balance between these two forms helps define the cellular redox environment, and their ratio is often used as an indicator of oxidative stress. Because the sulfhydryl group is reactive, glutathione participates in many cellular processes, including detoxification and protein regulation.
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.
== Development == The pulp has a background similar to that of dentin because both are derived from the dental papilla of the tooth germ. During odontogenesis, when the dentin forms around the dental papilla, the innermost tissue is considered pulp.
Starmer says he has taken account of whether it would be right "to impose a further burden on the taxpayer". MSPs vote unanimously in favour of plans to ban dual mandates. Following an external review into the use of messaging services, Scotland's Deputy First Minister, Kate Forbes announces that Scottish Government ministers and staff will be banned from using WhatsApp for official business. Former First Minister of Scotland Humza Yousaf announces he will step down as an MSP at the 2026 Scottish Parliament election. Democracy and Boundary Commission Cymru unveils the names of the 16 constituencies that will make up the enlarged Senedd from 2026, with all but four of them known by exclusively Welsh language names. The Welsh Conservatives reaffirm their commitment to devolution following a social media post by MS Joel James, who said he wanted to get "rid" of the Senedd; the post, in response to the announcement of the constituencies for the 2026 election, was swiftly deleted. Nigel Farage says that Reform UK are in "open negotiations" with US billionaire Elon Musk about him donating to the party after the pair met at Donald Trump's Mar-a-Lago estate in Florida. 18 December – Reform UK confirms that Craig Campbell, a party official in Scotland, has been removed from his post after revelations his family has links to Ulster Loyalists and has a relatives who was convicted of murdering a Celtic fan. Police are called to what is described as a heated meeting of Oldham Council.
The set can be summed up mainly by high blood pressure, unhealthy cholesterol levels (high LDL, low HDL), chronic mild high blood sugar, and tendency toward overweight, especially in the abdomen. Metabolic syndrome overlaps or correlates with prediabetes. Metabolism metabolism is the sum of all the processes involved in using food to produce chemical energy for cell functions. It is a complex interaction of enzymes, substrates, intermediate products, etc. diabetes mellitus is a derangement of metabolism. Metformin A drug treatment for type 2 diabetes; belongs to a class of drugs called biguanides. First-line pharmacotherapy for type 2 diabetes mellitus. Mg/dL Milligrams per deciliter. How much glucose (sugar) is in a specific amount of blood. In self-monitoring of blood glucose, test results are given as the amount of glucose in milligrams per deciliter of blood. A fasting reading of 70 to 110 mg/dL is considered in the normal (nondiabetic) range. (This is the standard measurement of blood sugar in the US. The rest of the world uses mmol/L) Microaneurysm A small swelling that forms on the side of tiny blood vessels. These small swellings may break and bleed into nearby tissue. People with diabetes sometimes get microaneurysms in the retina of the eye. Microangiopathy See: Angiopathy. Microvascular disease Disease of the smallest blood vessels that sometimes occurs when a person has had diabetes for a long time. Mixed dose Combining two kinds of insulin in one injection.
=== Sailboat keel === Pen Duick VI, a boat designed by André Mauric and used for racing, was equipped with a keel of depleted uranium. The benefit is that, because of the very high density of uranium, the keel could be thinner for a given weight, and so have less resistance than a normal keel. It was later replaced by a standard lead keel.
==== Mechanism of action ==== The mechanism of action of biguanides is not fully understood, and many mechanisms have been proposed for metformin. Biguanides do not affect the output of insulin, unlike other hypoglycemic agents such as sulfonylureas and meglitinides. Therefore, they are effective in Type 2 diabetics; and in Type 1 diabetes when used in conjunction with insulin therapy. Mainly used in Type II diabetes, metformin is considered to increase insulin sensitivity in vivo, resulting in reduced plasma glucose concentrations, increased glucose uptake, and decreased gluconeogenesis. However, in hyperinsulinemia, biguanides can lower fasting levels of insulin in plasma. Their therapeutic uses derive from their tendency to reduce gluconeogenesis in the liver, and, as a result, reduce the level of glucose in the blood. Biguanides also tend to make the cells of the body more willing to absorb glucose already present in the bloodstream, and there again reducing the level of glucose in the plasma. Biguanides have been shown to interact with copper, specifically in mitochondria, where they interfere with cell metabolism by chelating Copper in its 2+ oxidation state (Cu(II)).
Sources: en.wikipedia.org
==== Organisation (1982–2018) ==== 1st Hydropower Corps - Formerly the Basic Engineering Corps 61st Detachment; Headquarters in Nanning 1st Hydropower Detachment 2nd Hydropower Detachment 3rd Hydropower Detachment Search and rescue company 4th Hydropower Detachment 5th Hydropower Detachment 2nd Hydropower Corps - Formerly the Basic Engineering Corps 63rd Detachment 7th Hydropower Detachment 8th Hydropower Detachment 9th Hydropower Detachment 3rd Hydropower Corps 10th Hydropower Detachment 12th Hydropower Detachment
Black eschars are most frequently attributed in medicine to cutaneous anthrax (infection by Bacillus anthracis), which may be contracted through herd animal exposure and also from Pasteurella multocida exposure in cats and rabbits. A newly identified human rickettsial infection, R. parkeri rickettsiosis, can be differentiated from Rocky Mountain spotted fever by the presence of an eschar at the site of inoculation. Eschar is sometimes called a black wound because the wound is covered with thick, dry, black necrotic tissue. Eschar may be allowed to slough off naturally, or it may require surgical removal (debridement) to prevent infection, especially in immunocompromised patients (e.g. if a skin graft is to be conducted). If eschar is on a limb, it is important to assess peripheral pulses of the affected limb to make sure blood and lymphatic circulation is not compromised. If circulation is compromised, an escharotomy, or surgical incision through the eschar, may be indicated.
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== Composition == Royal jelly is 67% water, 12.5% protein, 11% simple sugars (monosaccharides), 6% fatty acids and 3.5% 10-hydroxy-2-decenoic acid (10-HDA). It also contains trace minerals, antibacterial and antibiotic components, pantothenic acid (vitamin B5), pyridoxine (vitamin B6) and trace amounts of vitamin C, but none of the fat-soluble vitamins: A, D, E or K.
=== EC 2.1.1: Methyltransferases === EC 2.1.1.1: nicotinamide N-methyltransferase EC 2.1.1.2: guanidinoacetate N-methyltransferase EC 2.1.1.3: thetin—homocysteine S-methyltransferase EC 2.1.1.4: acetylserotonin O-methyltransferase EC 2.1.1.5: betaine—homocysteine S-methyltransferase EC 2.1.1.6: catechol O-methyltransferase EC 2.1.1.7: nicotinate N-methyltransferase EC 2.1.1.8: histamine N-methyltransferase EC 2.1.1.9: thiol S-methyltransferase EC 2.1.1.10: homocysteine S-methyltransferase EC 2.1.1.11: magnesium protoporphyrin IX methyltransferase EC 2.1.1.12: methionine S-methyltransferase EC 2.1.1.13: methionine synthase EC 2.1.1.14: 5-methyltetrahydropteroyltriglutamate—homocysteine S-methyltransferase EC 2.1.1.15: fatty-acid O-methyltransferase EC 2.1.1.16: methylene-fatty-acyl-phospholipid synthase EC 2.1.1.17: phosphatidylethanolamine N-methyltransferase EC 2.1.1.18: polysaccharide O-methyltransferase EC 2.1.1.19: trimethylsulfonium—tetrahydrofolate N-methyltransferase EC 2.1.1.20: glycine N-methyltransferase EC 2.1.1.21: methylamine—glutamate N-methyltransferase EC 2.1.1.22: carnosine N-methyltransferase EC 2.1.1.23: now covered by EC 2.1.1.124, EC 2.1.1.125 and EC 2.1.1.126 EC 2.1.1.24: now covered by EC 2.1.1.77, EC 2.1.1.80 and EC 2.1.1.100 EC 2.1.1.25: phenol O-methyltransferase EC 2.1.1.26: iodophenol O-methyltransferase EC 2.1.1.27: tyramine N-methyltransferase EC 2.1.1.28: phenylethanolamine N-methyltransferase EC 2.1.1.29: Now covered by EC 2.1.1.202, EC 2.1.1.203 and EC .1.1.204 EC 2.1.1.30: tRNA (purine-2- or -6-)-methyltransferase: Reactions previously described are due to EC 2.1.1.32 EC 2.1.1.31: Now covered by EC 2.1.1.221 and EC 2.1.1.228 EC 2.1.1.32: Now covered by EC 2.1.1.213, EC 2.1.1.214, EC 2.1.1.215 and EC 2.1.1.216 EC 2.1.1.33: tRNA (guanine46-N7)-methyltransferase EC 2.1.1.34: tRNA (guanosine18-2′-O)-methyltransferase EC 2.1.1.35: tRNA (uracil54-C5)-methyltransferase EC 2.1.1.36: Now covered by EC 2.1.1.217, EC 2.1.1.218, EC 2.1.1.219, EC 2.1.1.220 EC 2.1.1.37: DNA (cytosine-5-)-methyltransferase EC 2.1.1.38: O-demethylpuromycin O-methyltransferase EC 2.1.1.39: inositol 3-methyltransferase EC 2.1.1.40: inositol 1-methyltransferase EC 2.1.1.41: sterol 24-C-methyltransferase EC 2.1.1.42: flavone 3′-O-methyltransferase EC 2.1.1.43: Now described by EC 2.1.1.354, EC 2.1.1.355, EC 2.1.1.356, EC 2.1.1.357, EC 2.1.1.358, EC 2.1.1.359, EC 2.1.1.360, EC 2.1.1.361 and EC 2.1.1.362 EC 2.1.1.44: L-histidine Nα-methyltransferase EC 2.1.1.45: thymidylate synthase EC 2.1.1.46: isoflavone 4′-O-methyltransferase EC 2.1.1.47: indolepyruvate C-methyltransferase EC 2.1.1.48: Now covered by EC 2.1.1.181, EC 2.1.1.182, EC 2.1.1.183 and EC 2.1.1.184 EC 2.1.1.49: amine N-methyltransferase EC 2.1.1.50: loganate O-methyltransferase EC 2.1.1.51: Now covered by EC 2.1.1.187 and EC 2.1.1.188 EC 2.1.1.52: Now covered by EC 2.1.1.171, EC 2.1.1.172, EC 2.1.1.173 and EC 2.1.1.174 EC 2.1.1.53: putrescine N-methyltransferase EC 2.1.1.54: deoxycytidylate C-methyltransferase EC 2.1.1.55: tRNA (adenine-N6-)-methyltransferase EC 2.1.1.56: mRNA (guanine-N7)-methyltransferase EC 2.1.1.57: methyltransferase cap1 EC 2.1.1.58: deleted, included in EC 2.1.1.57 EC 2.1.1.59: [cytochrome c]-lysine N-methyltransferase EC 2.1.1.60: calmodulin-lysine N-methyltransferase EC 2.1.1.61: tRNA (5-methylaminomethyl-2-thiouridylate)-methyltransferase EC 2.1.1.62: mRNA (2′-O-methyladenosine-N6-)-methyltransferase EC 2.1.1.63: methylated-DNA—[protein]-cysteine S-methyltransferase EC 2.1.1.64: 3-demethylubiquinol 3-O-methyltransferase EC 2.1.1.65: licodione 2′-O-methyltransferase EC 2.1.1.66: Now covered by EC 2.1.1.230 EC 2.1.1.67: thiopurine S-methyltransferase EC 2.1.1.68: caffeate O-methyltransferase EC 2.1.1.69: 5-hydroxyfuranocoumarin 5-O-methyltransferase EC 2.1.1.70: 8-hydroxyfuranocoumarin 8-O-methyltransferase EC 2.1.1.71: phosphatidyl-N-methylethanolamine N-methyltransferase EC 2.1.1.72: site-specific DNA-methyltransferase (adenine-specific) EC 2.1.1.73: deleted: reaction is that of EC 2.1.1.37, DNA (cytosine-5-)-methyltransferase EC 2.1.1.74: methylenetetrahydrofolate—tRNA-(uracil54-C5)-methyltransferase [NAD(P)H-oxidizing] EC 2.1.1.75: apigenin 4′-O-methyltransferase EC 2.1.1.76: quercetin 3-O-methyltransferase EC 2.1.1.77: protein-L-isoaspartate(D-aspartate) O-methyltransferase EC 2.1.1.78: isoorientin 3′-O-methyltransferase EC 2.1.1.79: cyclopropane-fatty-acyl-phospholipid synthase EC 2.1.1.80: protein-glutamate O-methyltransferase EC 2.1.1.81: deleted, included in EC 2.1.1.49 EC 2.1.1.82: 3-methylquercetin 7-O-methyltransferase EC 2.1.1.83: 3,7-dimethylquercetin 4′-O-methyltransferase EC 2.1.1.84: methylquercetagetin 6-O-methyltransferase EC 2.1.1.85: protein-histidine N-methyltransferase EC 2.1.1.86: Now covered by EC 7.2.1.4 EC 2.1.1.87: pyridine N-methyltransferase EC 2.1.1.88: 8-hydroxyquercetin 8-O-methyltransferase EC 2.1.1.89: tetrahydrocolumbamine 2-O-methyltransferase EC 2.1.1.90: methanol—5-hydroxybenzimidazolylcobamide Co-methyltransferase EC 2.1.1.91: isobutyraldoxime O-methyltransferase EC 2.1.1.92: Now included with EC 2.1.1.69 EC 2.1.1.93: is identical to EC 2.1.1.70, 8-hydroxyfuranocoumarin 8-O-methyltransferase EC 2.1.1.94: tabersonine 16-O-methyltransferase EC 2.1.1.95: tocopherol C-methyltransferase EC 2.1.1.96: thioether S-methyltransferase EC 2.1.1.97: 3-hydroxyanthranilate 4-C-methyltransferase EC 2.1.1.98: diphthine synthase EC 2.1.1.99: 3-hydroxy-16-methoxy-2,3-dihydrotabersonine N-methyltransferase EC 2.1.1.100: protein-S-isoprenylcysteine O-methyltransferase EC 2.1.1.101: macrocin O-methyltransferase EC 2.1.1.102: demethylmacrocin O-methyltransferase EC 2.1.1.103: phosphoethanolamine N-methyltransferase EC 2.1.1.104: caffeoyl-CoA O-methyltransferase EC 2.1.1.105: N-benzoyl-4-hydroxyanthranilate 4-O-methyltransferase EC 2.1.1.106: tryptophan 2-C-methyltransferase EC 2.1.1.107: uroporphyrinogen-III C-methyltransferase EC 2.1.1.108: 6-hydroxymellein O-methyltransferase EC 2.1.1.109: demethylsterigmatocystin 6-O-methyltransferase EC 2.1.1.110: sterigmatocystin 8-O-methyltransferase EC 2.1.1.111: anthranilate N-methyltransferase EC 2.1.1.112: glucuronoxylan 4-O-methyltransferase EC 2.1.1.113: site-specific DNA-methyltransferase (cytosine-N4-specific) EC 2.1.1.114: polyprenyldihydroxybenzoate methyltransferase EC 2.1.1.115: (RS)-1-benzyl-1,2,3,4-tetrahydroisoquinoline N-methyltransferase EC 2.1.1.116: 3′-hydroxy-N-methyl-(S)-coclaurine 4′-O-methyltransferase EC 2.1.1.117: (S)-scoulerine 9-O-methyltransferase EC 2.1.1.118: columbamine O-methyltransferase EC 2.1.1.119: 10-hydroxydihydrosanguinarine 10-O-methyltransferase EC 2.1.1.120: 12-hydroxydihydrochelirubine 12-O-methyltransferase EC 2.1.1.121: 6-O-methylnorlaudanosoline 5′-O-methyltransferase EC 2.1.1.122: (S)-tetrahydroprotoberberine N-methyltransferase EC 2.1.1.123: [cytochrome-c]-methionine S-methyltransferase EC 2.1.1.124: Now covered by EC 2.1.1.319, EC 2.1.1.320, EC 2.1.1.321 and EC 2.1.1.322 EC 2.1.1.125: Now covered by EC 2.1.1.319, EC 2.1.1.320 and EC 2.1.1.321 EC 2.1.1.126: Now covered by EC 2.1.1.319, EC 2.1.1.320 and EC 2.1.1.321 EC 2.1.1.127: [ribulose-bisphosphate carboxylase]-lysine N-methyltransferase EC 2.1.1.128: (RS)-norcoclaurine 6-O-methyltransferase EC 2.1.1.129: inositol 4-methyltransferase EC 2.1.1.130: precorrin-2 C20-methyltransferase EC 2.1.1.131: precorrin-2 C17-methyltransferase EC 2.1.1.132: precorrin-6B C5,15-methyltransferase (decarboxylating) EC 2.1.1.133: precorrin-4 C11-methyltransferase EC 2.1.1.134: now with EC 2.1.1.129 EC 2.1.1.135: now EC 1.16.1.8 EC 2.1.1.136: chlorophenol O-methyltransferase EC 2.1.1.137: arsenite methyltransferase EC 2.1.1.138: deleted: Reaction due to EC 2.1.1.137 EC 2.1.1.139: 3′-demethylstaurosporine O-methyltransferase EC 2.1.1.140: (S)-coclaurine-N-methyltransferase EC 2.1.1.141: jasmonate O-methyltransferase EC 2.1.1.142: cycloartenol 24-C-methyltransferase EC 2.1.1.143: 24-methylenesterol C-methyltransferase EC 2.1.1.144: trans-aconitate 2-methyltransferase EC 2.1.1.145: trans-aconitate 3-methyltransferase EC 2.1.1.146: (iso)eugenol O-methyltransferase EC 2.1.1.147: corydaline synthase EC 2.1.1.148: thymidylate synthase (FAD) EC 2.1.1.149: Now covered by EC 2.1.1.267, flavonoid 3′,5′-methyltransferase EC 2.1.1.150: isoflavone 7-O-methyltransferase EC 2.1.1.151: cobalt-factor II C20-methyltransferase EC 2.1.1.152: precorrin-6A synthase (deacetylating) EC 2.1.1.153: vitexin 2′′-O-rhamnoside 7-O-methyltransferase EC 2.1.1.154: isoliquiritigenin 2′-O-methyltransferase EC 2.1.1.155: kaempferol 4′-O-methyltransferase EC 2.1.1.156: glycine/sarcosine N-methyltransferase EC 2.1.1.157: sarcosine/dimethylglycine N-methyltransferase EC 2.1.1.158: 7-methylxanthosine synthase EC 2.1.1.159: theobromine synthase EC 2.1.1.160: caffeine synthase EC 2.1.1.161: dimethylglycine N-methyltransferase EC 2.1.1.162: glycine/sarcosine/dimethylglycine N-methyltransferase EC 2.1.1.163: demethylmenaquinone methyltransferase EC 2.1.1.164: demethylrebeccamycin-D-glucose O-methyltransferase EC 2.1.1.165: methyl halide transferase EC 2.1.1.166: 23S rRNA (uridine2552-2′-O)-methyltransferase EC 2.1.1.167: 27S pre-rRNA (guanosine2922-2′-O)-methyltransferase EC 2.1.1.168: 21S rRNA (uridine2791-2′-O)-methyltransferase EC 2.1.1.169: tricetin 3′,4′,5′-O-trimethyltransferase EC 2.1.1.170: 16S rRNA (guanine527-N7)-methyltransferase EC 2.1.1.171: 16S rRNA (guanine966-N2)-methyltransferase EC 2.1.1.172: 16S rRNA (guanine1207-N2))-methyltransferase EC 2.1.1.173: 23S rRNA (guanine2445-N2)-methyltransferase EC 2.1.1.174: 23S rRNA (guanine1835-N2)-methyltransferase EC 2.1.1.175: tricin synthase EC 2.1.1.176: 16S rRNA (cytosine967-C5)-methyltransferase EC 2.1.1.177: 23S rRNA (pseudouridine1915-N3)-methyltransferase EC 2.1.1.178: 16S rRNA (cytosine1407-C5)-methyltransferase EC 2.1.1.179: 16S rRNA (guanine1405-N7)-methyltransferase EC 2.1.1.180: 16S rRNA (adenine1408-N1)-methyltransferase EC 2.1.1.181: 23S rRNA (adenine1618-N6)-methyltransferase EC 2.1.1.182: 16S rRNA (adenine1518-N6/adenineadenine1519-N6)-dimethyltransferase EC 2.1.1.183: 18S rRNA (adenine1779-N6/adenine1780-N6)-dimethyltransferase EC 2.1.1.184: 23S rRNA (adenine2085-N6)-dimethyltransferase EC 2.1.1.185: 23S rRNA (guanosine2251-2′-O)-methyltransferase EC 2.1.1.186: 23S rRNA (cytidine2498-2′-O)-methyltransferase EC 2.1.1.187: 23S rRNA (guanine745-N1)-methyltransferase EC 2.1.1.188: 23S rRNA (guanine748-N1)-methyltransferase EC 2.1.1.189: 23S rRNA (uracil747-C5)-methyltransferase EC 2.1.1.190: 23S rRNA (uracil1939-C5)-methyltransferase EC 2.1.1.191: 23S rRNA (cytosine1962-C5)-methyltransferase EC 2.1.1.192: 23S rRNA (adenine2503-C2)-methyltransferase EC 2.1.1.193: 16S rRNA (uracil1498-N3)-methyltransferase EC 2.1.1.194: A mixture of EC 2.1.1.192 and EC 2.1.1.224 EC 2.1.1.195: cobalt-precorrin-5B (C1)-methyltransferase EC 2.1.1.196: cobalt-precorrin-7 (C15)-methyltransferase (decarboxylating) EC 2.1.1.197: malonyl-[acyl-carrier protein] O-methyltransferase EC 2.1.1.198: 16S rRNA (cytidine1402-2′-O)-methyltransferase EC 2.1.1.199: 16S rRNA (cytosine1402-N4)-methyltransferase EC 2.1.1.200: tRNA (cytidine32/uridine32-2′-O)-methyltransferase EC 2.1.1.201: 2-methoxy-6-polyprenyl-1,4-benzoquinol methylase EC 2.1.1.202: multisite-specific tRNA:(cytosine-C5)-methyltransferase EC 2.1.1.203: tRNA (cytosine34-C5)-methyltransferase EC 2.1.1.204: tRNA (cytosine38-C5)-methyltransferase EC 2.1.1.205: tRNA (cytidine32/guanosine34-2′-O)-methyltransferase EC 2.1.1.206: tRNA (cytidine56-2′-O)-methyltransferase EC 2.1.1.207: tRNA (cytidine34-2′-O)-methyltransferase EC 2.1.1.208: 23S rRNA (uridine2479-2′-O)-methyltransferase EC 2.1.1.209: 23S rRNA (guanine2535-N1)-methyltransferase EC 2.1.1.210: demethylspheroidene O-methyltransferase EC 2.1.1.211: tRNASer(uridine44-2′-O)-methyltransferase EC 2.1.1.212: 2,7,4′-trihydroxyisoflavanone 4′-O-methyltransferase EC 2.1.1.213: tRNA (guanine110-N2)-dimethyltransferase EC 2.1.1.214: tRNA (guanine10-N2)-methyltransferase EC 2.1.1.215: tRNA (guanine26-N2/guanine27-N2)-dimethyltransferase EC 2.1.1.216: tRNA (guanine26-N2)-dimethyltransferase EC 2.1.1.217: tRNA (adenine22-N1)-methyltransferase EC 2.1.1.218: tRNA (adenine9-N1)-methyltransferase EC 2.1.1.219: tRNA (adenine57-N1/adenine58-N1)-methyltransferase EC 2.1.1.220: tRNA (adenine58-N1)-methyltransferase EC 2.1.1.221: tRNA (guanine9-N1)-methyltransferase EC 2.1.1.222: 2-polyprenyl-6-hydroxyphenyl methylase EC 2.1.1.223: tRNA1Val (adenine937-N6)-methyltransferase EC 2.1.1.224: 23S rRNA (adenine2503-C8)-methyltransferase EC 2.1.1.225: tRNA:m4X modification enzyme EC 2.1.1.226: 23S rRNA (cytidine1920-2′-O)-methyltransferase EC 2.1.1.227: 16S rRNA (cytidine1409-2′-O)-methyltransferase EC 2.1.1.228: tRNA (guanine37-N1)-methyltransferase EC 2.1.1.229: tRNA (carboxymethyluridine34-5-O)-methyltransferase EC 2.1.1.230: 23S rRNA (adenosine1067-2′-O)-methyltransferase EC 2.1.1.231: flavonoid 4′-O-methyltransferase EC 2.1.1.232: naringenin 7-O-methyltransferase EC 2.1.1.233: [phosphatase 2A protein]-leucine-carboxy methyltransferase EC 2.1.1.234: dTDP-3-amino-3,4,6-trideoxy-α-D-glucopyranose N,N-dimethyltransferase EC 2.1.1.235: dTDP-3-amino-3,6-dideoxy-α-D-glucopyranose N,N-dimethyltransferase EC 2.1.1.236: dTDP-3-amino-3,6-dideoxy-α-D-galactopyranose N,N-dimethyltransferase EC 2.1.1.237: mycinamicin III 3′′-O-methyltransferase EC 2.1.1.238: mycinamicin VI 2′′-O-methyltransferaseD EC 2.1.1.239: L-olivosyl-oleandolide 3-O-methyltransferase EC 2.1.1.240: trans-resveratrol di-O-methyltransferase EC 2.1.1.241: 2,4,7-trihydroxy-1,4-benzoxazin-3-one-glucoside 7-O-methyltransferase EC 2.1.1.242: 16S rRNA (guanine1516-N2)-methyltransferase EC 2.1.1.243: 2-ketoarginine methyltransferase EC 2.1.1.244: protein N-terminal methyltransferase EC 2.1.1.245: 5-methyltetrahydrosarcinapterin—corrinoid/iron-sulfur protein Co-methyltransferase EC 2.1.1.246: [methyl-Co(III) methanol-specific corrinoid protein]—coenzyme M methyltransferase EC 2.1.1.247: (methyl-Co(III) methylamine-specific corrinoid protein)—coenzyme M methyltransferase EC 2.1.1.248: methylamine—corrinoid protein Co-methyltransferase EC 2.1.1.249: dimethylamine—corrinoid protein Co-methyltransferase EC 2.1.1.250: trimethylamine—corrinoid protein Co-methyltransferase EC 2.1.1.251: methylated-thiol—coenzyme M methyltransferase EC 2.1.1.252: tetramethylammonium—corrinoid protein Co-methyltransferase EC 2.1.1.253: [methyl-Co(III) tetramethylammonium-specific corrinoid protein]—coenzyme M methyltransferase EC 2.1.1.254: erythromycin 3′′-O-methyltransferase EC 2.1.1.255: geranyl diphosphate 2-C-methyltransferase EC 2.1.1.256: tRNA (guanine6-N6-methyltransferase) EC 2.1.1.257: tRNA (pseudouridine54-N1)-methyltransferase EC 2.1.1.258: 5-methyltetrahydrofolate—corrinoid/iron-sulfur protein Co-methyltransferase EC 2.1.1.259: [fructose-bisphosphate aldolase]-lysine N-methyltransferase EC 2.1.1.260: rRNA small subunit pseudouridine methyltransferase Nep1 EC 2.1.1.261: 4-dimethylallyltryptophan N-methyltransferase EC 2.1.1.262: squalene methyltransferase EC 2.1.1.263: botryococcene C-methyltransferase EC 2.1.1.264: 23S rRNA (guanine2069-N7)-methyltransferase EC 2.1.1.265: tellurite methyltransferase EC 2.1.1.266: 23S rRNA (adenine2030-N6)-methyltransferase EC 2.1.1.267: flavonoid 3′,5′-methyltransferase EC 2.1.1.268: tRNAThr (cytosine32-N3)-methyltransferase EC 2.1.1.269: dimethylsulfoniopropionate demethylase EC 2.1.1.270: (+)-6a-hydroxymaackiain 3-O-methyltransferase EC 2.1.1.271: cobalt-precorrin-4 methyltransferase EC 2.1.1.272: cobalt-factor III methyltransferase EC 2.1.1.273: benzoate O-methyltransferase EC 2.1.1.274: salicylate 1-O-methyltransferase EC 2.1.1.275: gibberellin A9 O-methyltransferase EC 2.1.1.276: gibberellin A4 carboxyl methyltransferase EC 2.1.1.277: anthranilate O-methyltransferase EC 2.1.1.278: indole-3-acetate O-methyltransferase EC 2.1.1.279: trans-anol O-methyltransferase EC 2.1.1.280: selenocysteine Se-methyltransferase EC 2.1.1.281: phenylpyruvate C3-methyltransferase EC 2.1.1.282: tRNAPhe 7-[(3-amino-3-carboxypropyl)-4-demethylwyosine37-N4]-methyltransferase EC 2.1.1.283: emodin O-methyltransferase EC 2.1.1.284: 8-demethylnovobiocic acid C8-methyltransferase EC 2.1.1.285: demethyldecarbamoylnovobiocin O-methyltransferase EC 2.1.1.286: 25S rRNA (adenine2142-N1)-methyltransferase EC 2.1.1.287: 25S rRNA (adenine645-N1)-methyltransferase EC 2.1.1.288: aklanonic acid methyltransferase EC 2.1.1.289: cobalt-precorrin-7 (C5)-methyltransferase EC 2.1.1.290: tRNAPhe [7-(3-amino-3-carboxypropyl)wyosine37-O]-methyltransferase EC 2.1.1.291: (R,S)-reticuline 7-O-methyltransferase EC 2.1.1.292: carminomycin 4-O-methyltransferase EC 2.1.1.293: 6-hydroxytryprostatin B O-methyltransferase EC 2.1.1.294: 3-O-phospho-polymannosyl GlcNAc-diphospho-ditrans,octacis-undecaprenol 3-phospho-methyltransferase EC 2.1.1.295: 2-methyl-6-phytyl-1,4-hydroquinone methyltransferase EC 2.1.1.296: methyltransferase cap2 EC 2.1.1.297: peptide chain release factor N5-glutamine methyltransferase EC 2.1.1.298: ribosomal protein L3 N5-glutamine methyltransferase EC 2.1.1.299: protein N-terminal monomethyltransferase EC 2.1.1.300: pavine N-methyltransferase EC 2.1.1.301: cypemycin N-terminal methyltransferase EC 2.1.1.302: 3-hydroxy-5-methyl-1-naphthoate 3-O-methyltransferase EC 2.1.1.303: 2,7-dihydroxy-5-methyl-1-naphthoate 7-O-methyltransferase EC 2.1.1.304: L-tyrosine C3-methyltransferase EC 2.1.1.305: 8-demethyl-8-α-L-rhamnosyltetracenomycin-C 2′-O-methyltransferase EC 2.1.1.306: 8-demethyl-8-(2-methoxy-α-L-rhamnosyl)tetracenomycin-C 3′-O-methyltransferase EC 2.1.1.307: 8-demethyl-8-(2,3-dimethoxy-α-L-rhamnosyl)tetracenomycin-C 4′-O-methyltransferase EC 2.1.1.308: cytidylyl-2-hydroxyethylphosphonate methyltransferase EC 2.1.1.309: 18S rRNA (guanine1575-N7)-methyltransferase EC 2.1.1.310: 25S rRNA (cytosine2870-C5)-methyltransferase EC 2.1.1.311: 25S rRNA (cytosine2278-C5)-methyltransferase EC 2.1.1.312: 25S rRNA (uracil2843-N3)-methyltransferase EC 2.1.1.313: 25S rRNA (uracil2634-N3)-methyltransferase EC 2.1.1.314: diphthine methyl ester synthase EC 2.1.1.315: 27-O-demethylrifamycin SV methyltransferase EC 2.1.1.316: mitomycin 6-O-methyltransferase EC 2.1.1.317: sphingolipid C9-methyltransferase EC 2.1.1.318: [trehalose-6-phosphate synthase]-L-cysteine S-methyltransferase EC 2.1.1.319: type I protein arginine methyltransferase EC 2.1.1.320: type II protein arginine methyltransferase EC 2.1.1.321: type III protein arginine methyltransferase EC 2.1.1.322: type IV protein arginine methyltransferase EC 2.1.1.323: (–)-pluviatolide 4-O-methyltransferase EC 2.1.1.324: dTDP-4-amino-2,3,4,6-tetradeoxy-D-glucose N,N-dimethyltransferase EC 2.1.1.325: juvenile hormone-III synthase EC 2.1.1.326: N-acetyldemethylphosphinothricin P-methyltransferase EC 2.1.1.327: phenazine-1-carboxylate N-methyltransferase EC 2.1.1.328: N-demethylindolmycin N-methyltransferase EC 2.1.1.329: demethylphylloquinol methyltransferase EC 2.1.1.330: 5′-demethylyatein 5′-O-methyltransferase EC 2.1.1.331: bacteriochlorophyllide d C-121-methyltransferase EC 2.1.1.332: bacteriochlorophyllide d C-82-methyltransferase EC 2.1.1.333: bacteriochlorophyllide d C-20 methyltransferase EC 2.1.1.334: methanethiol S-methyltransferase EC 2.1.1.335: 4-amino-anhydrotetracycline N4-methyltransferase EC 2.1.1.336: norbelladine O-methyltransferase EC 2.1.1.337: reticuline N-methyltransferase EC 2.1.1.338: desmethylxanthohumol 6′-O-methyltransferase EC 2.1.1.339: xanthohumol 4-O-methyltransferase EC 2.1.1.340: 3-aminomethylindole N'-methyltransferase EC 2.1.1.341: vanillate/3-O-methylgallate O-demethylase EC 2.1.1.342: anaerobilin synthase EC 2.1.1.343: 8-amino-8-demethylriboflavin N,N-dimethyltransferase EC 2.1.1.344: ornithine lipid N-methyltransferase EC 2.1.1.345: psilocybin synthase EC 2.1.1.346: U6 snRNA m6A methyltransferase EC 2.1.1.347: (+)-O-methylkolavelool synthase EC 2.1.1.348: mRNA m6A methyltransferase EC 2.1.1.349: toxoflavin synthase EC 2.1.1.350: menaquinone C8-methyltransferase EC 2.1.1.351: nocamycin O-methyltransferase EC 2.1.1.352: 3-O-acetyl-4′-O-demethylpapaveroxine 4′-O-methyltransferase EC 2.1.1.353: demethylluteothin O-methyltransferase EC 2.1.1.354: [histone H3]-lysine4 N-trimethyltransferase EC 2.1.1.355: [histone H3]-lysine9 N-trimethyltransferase EC 2.1.1.356: [histone H3]-lysine27 N-trimethyltransferase EC 2.1.1.357: [histone H3]-lysine36 N-dimethyltransferase EC 2.1.1.358: [histone H3]-dimethyl-L-lysine36 N-methyltransferase. Now known to have the activity of EC 2.1.1.359, [histone H3]-lysine36 N-trimethyltransferase. EC 2.1.1.359: [histone H3]-lysine36 N-trimethyltransferase EC 2.1.1.360: [histone H3]-lysine79 N-trimethyltransferase EC 2.1.1.361: [histone H4]-lysine20 N-methyltransferase EC 2.1.1.362: [histone H4]-N-methyl-L-lysine20 N-methyltransferase EC 2.1.1.363: pre-sodorifen synthase EC 2.1.1.364: [histone H3]-lysine4 N-methyltransferase EC 2.1.1.365: MMP 1-O-methyltransferase EC 2.1.1.366: [histone H3]-N6,N6-dimethyl-lysine9 N-methyltransferase EC 2.1.1.367: [histone H3]-lysine9 N-methyltransferase EC 2.1.1.368: [histone H3]-lysine9 N-dimethyltransferase EC 2.1.1.369: [histone H3]-lysine27 N-methyltransferase EC 2.1.1.370: [histone H3]-lysine4 N-dimethyltransferase EC 2.1.1.371: [histone H3]-lysine27 N-dimethyltransferase EC 2.1.1.372: [histone H4]-lysine20 N-trimethyltransferase EC 2.1.1.373: 2-hydroxy-4-(methylsulfanyl)butanoate S-methyltransferase EC 2.1.1.374: 2-heptyl-1-hydroxyquinolin-4(1H)-one methyltransferase EC 2.1.1.375: NNS virus cap methyltransferase EC 2.1.1.376: glycine betaine—corrinoid protein Co-methyltransferase EC 2.1.1.377: [methyl-Co(III) glycine betaine-specific corrinoid protein]—coenzyme M methyltransferase EC 2.1.1.378: [methyl-Co(III) glycine betaine-specific corrinoid protein]—tetrahydrofolate methyltransferase EC 2.1.1.379: [methyl coenzyme M reductase]-L-arginine C-5-methyltransferase
Sources: en.wikipedia.org
Common approaches include enzymatic recycling assays, HPLC, and LC-MS/MS. Acid extraction and rapid processing limit oxidation before analysis.
Reduced glutathione oxidizes easily and can change after collection. Delays, warmth, light, and repeated freezing can alter measured values.
Labels may state total glutathione without specifying reduced and oxidized content. Purity, counterions, and actual assay can vary between products.
Glutathione oxidizes quickly when cells are disrupted or when samples sit at room temperature. Rapid processing or immediate freezing minimizes the conversion of GSH to GSSG. This step helps ensure that the measured ratio reflects the original biological state.