Sulfur Group Transferases
One-Carbon Group Transferases
Nitrogenous Group Transferases
Sulfur
Biosynthesis and biological properties of compounds containing highly reactive, reduced sulfane sulfur. (1/1)
The covalent modifications of sulfhydryl groups (-SH) may occur through oxidation to mixed disulfides (S-thiolation), S-nitrosylation, as well as persulfide and trisulfide formation. The latter possibilities of -SH group modification connected with compounds containing sulfur called sulfane sulfur are described in this paper. Sulfane sulfur compounds contain a labile, highly reactive sulfur atom at a reduced oxidation state with a valence of 0 or -1, covalently bound to another sulfur atom. These compounds include persulfides, polysulfides, polythionates, thiosulfate, elemental sulfur and disulfides, which enable tautomerization to thiosulfoxides. Sulfane sulfur compounds are formed in the anaerobic cysteine sulfur metabolism with the participation of such enzymes as cystathionase (CST), 3-mercaptopyruvate sulfurtransferase (MpST) and rhodanese (thiosulfate: cyanide sulfurtransferase). Compounds containing sulfane sulfur participate in cell regulation processes through activation or inactivation of some enzymes. Other important roles of sulfane sulfur compounds are their antioxidative properties, significance in the processes of carcinogenesis, participation in the tRNA sulfuration as well as an influence on the activity of immune cells. To recognize completely the biological role of compounds with sulfane sulfur it is necessary to have sensitive methods of quantitative determination, so a review of these methods is presented in this paper. Moreover, biosynthetic pathways and biological properties of these compounds have been discussed. (+info)Sulfur Group Transferases are a group of enzymes that catalyze the transfer of a sulfur group from one molecule to another. These enzymes play a crucial role in various biological processes, including the metabolism of certain amino acids, such as methionine and cysteine, and the detoxification of xenobiotics (foreign substances) through the addition of sulfur groups.
The systematic name for this group of enzymes is sulfurtransferases, and they are classified under EC 2.8.1 in the Enzyme Commission numbering system. They can be further divided into subgroups based on their specific functions and the types of substrates they act upon. Examples of Sulfur Group Transferases include cysteine synthase, cysteine desulfurase, and rhodanese.
One-carbon group transferases are a class of enzymes that play a crucial role in transmitting one-carbon units (methyl or formyl groups) from one molecule to another during various metabolic processes. These enzymes use cofactors such as vitamin B12, folate, and S-adenosylmethionine (SAM) to facilitate the transfer of these one-carbon units. They are involved in several essential biochemical reactions, including:
1. The synthesis of amino acids like methionine, serine, and glycine.
2. The formation of purines and pyrimidines, which are the building blocks of DNA and RNA.
3. The methylation of proteins, lipids, and other molecules, which is critical for their regulation and function.
4. The detoxification of harmful substances by transferring one-carbon units to them, facilitating their elimination from the body.
Examples of one-carbon group transferases include methionine synthase, serine hydroxymethyltransferase, glycine cleavage system, and methylenetetrahydrofolate reductase (MTHFR). These enzymes are essential for maintaining cellular homeostasis and overall health. Genetic variations or deficiencies in these enzymes can lead to various diseases, such as neurological disorders, cardiovascular disease, and cancer.
Nitrogenous group transferases are a class of enzymes that catalyze the transfer of nitrogen-containing groups from one molecule to another. These enzymes play a crucial role in various metabolic pathways, including the biosynthesis and degradation of amino acids, nucleotides, and other nitrogen-containing compounds.
The term "nitrogenous group" refers to any chemical group that contains nitrogen atoms. Examples of nitrogenous groups include amino groups (-NH2), amide groups (-CONH2), and cyano groups (-CN). Transferases that move these groups from one molecule to another are classified as nitrogenous group transferases.
These enzymes typically require cofactors such as ATP, NAD+, or other small molecules to facilitate the transfer of the nitrogenous group. They follow the general reaction mechanism of a transferase enzyme, where the substrate (donor) binds to the active site of the enzyme and transfers its nitrogenous group to an acceptor molecule, resulting in the formation of a new product.
Examples of nitrogenous group transferases include:
* Glutamine synthetase, which catalyzes the conversion of glutamate to glutamine by adding an ammonia group (-NH3) from ATP.
* Aspartate transcarbamylase, which catalyzes the transfer of a carbamoyl group (-CO-NH2) from carbamoyl phosphate to aspartate during pyrimidine biosynthesis.
* Argininosuccinate synthetase, which catalyzes the formation of argininosuccinate by transferring an aspartate group from aspartate to citrulline during the urea cycle.
Understanding nitrogenous group transferases is essential for understanding various metabolic pathways and their regulation in living organisms.
Sulfur is not typically referred to in the context of a medical definition, as it is an element found in nature and not a specific medical condition or concept. However, sulfur does have some relevance to certain medical topics:
* Sulfur is an essential element that is a component of several amino acids (the building blocks of proteins) and is necessary for the proper functioning of enzymes and other biological processes in the body.
* Sulfur-containing compounds, such as glutathione, play important roles in antioxidant defense and detoxification in the body.
* Some medications and supplements contain sulfur or sulfur-containing compounds, such as dimethyl sulfoxide (DMSO), which is used topically for pain relief and inflammation.
* Sulfur baths and other forms of sulfur-based therapies have been used historically in alternative medicine to treat various conditions, although their effectiveness is not well-established by scientific research.
It's important to note that while sulfur itself is not a medical term, it can be relevant to certain medical topics and should be discussed with a healthcare professional if you have any questions or concerns about its use in medications, supplements, or therapies.
Oxidoreductases acting on sulfur group donors are a class of enzymes that catalyze redox reactions involving sulfur group donors. These enzymes play a crucial role in various biological processes, such as the metabolism of sulfur-containing compounds and the detoxification of xenobiotics.
The term "oxidoreductase" refers to any enzyme that catalyzes an oxidation-reduction reaction, where one molecule is oxidized (loses electrons) and another is reduced (gains electrons). In the case of oxidoreductases acting on sulfur group donors, the sulfur atom in the substrate serves as the electron donor.
The systematic name for this class of enzymes follows a specific format: "donor:acceptor oxidoreductase." The donor is the sulfur-containing compound that donates electrons, and the acceptor is the molecule that accepts the electrons. For example, the enzyme that catalyzes the reaction between glutathione (GSH) and a variety of electrophiles is called glutathione transferase, or GST (donor:acceptor oxidoreductase).
These enzymes are further classified into subclasses based on the type of acceptor involved in the reaction. Examples include:
* EC 1.8.1: Oxidoreductases acting on CH-NH2 group donors
* EC 1.8.3: Oxidoreductases acting on CH or CH2 groups
* EC 1.8.4: Oxidoreductases acting on the CH-CH group of donors
* EC 1.8.5: Oxidoreductases acting on a sulfur group of donors
* EC 1.8.6: Oxidoreductases acting on NADH or NADPH
The subclass EC 1.8.5, oxidoreductases acting on a sulfur group of donors, includes enzymes that catalyze redox reactions involving sulfur-containing compounds such as thiols (compounds containing -SH groups), disulfides (-S-S- bonds), and other sulfur-containing functional groups. These enzymes play crucial roles in various biological processes, including detoxification, antioxidant defense, and redox regulation.
Glutathione-S-transfera1
- SAMe metabolism supports the synthesis of glutathione (GSH) and glutathione-dependent enzymes (glutathione peroxi-dase, glutathione reductase and glutathione-S-transferase), which comprise a complex antioxidant system important for liver function, including Phase II detoxification. (jarrow.com)
Alkyl3
- Alkyl and Aryl Transferases" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (jefferson.edu)
- A somewhat heterogeneous class of enzymes that catalyze the transfer of alkyl or related groups (excluding methyl groups). (jefferson.edu)
- Below are the most recent publications written about "Alkyl and Aryl Transferases" by people in Profiles. (jefferson.edu)
Classification1
- Classification of transferases continues to this day, with new ones being discovered frequently. (wikipedia.org)
Coenzyme2
- Enzymes that catalyze the transfer of sulfur atoms (2.8.1), sulfur groups (2.8.2) or coenzyme A (2.8.3). (uams.edu)
- Three examples of these reactions are the activity of coenzyme A (CoA) transferase, which transfers thiol esters, the action of N-acetyltransferase, which is part of the pathway that metabolizes tryptophan, and the regulation of pyruvate dehydrogenase (PDH), which converts pyruvate to acetyl CoA. (wikipedia.org)
Catalytic activity1
- This suggested the possibility of an SH group participating in the catalytic activity of the enzyme. (who.int)
Enzymes that catalyze the transfer1
- The same questions and strategies apply to sulfurtransferases, enzymes that catalyze the transfer of a sulfur atom from sulfur donors to nucleophilic sulfur acceptors (trans-persulfidation) by forming themselves persulfides. (hal.science)
Donor8
- A transferase is any one of a class of enzymes that catalyse the transfer of specific functional groups (e.g. a methyl or glycosyl group) from one molecule (called the donor) to another (called the acceptor). (wikipedia.org)
- Mechanistically, an enzyme that catalyzed the following reaction would be a transferase: X g r o u p + Y → t r a n s f e r a s e X + Y g r o u p {\displaystyle Xgroup+Y{\xrightarrow[{transferase}]{}}X+Ygroup} In the above reaction, X would be the donor, and Y would be the acceptor. (wikipedia.org)
- Systematic names of transferases are constructed in the form of "donor:acceptor grouptransferase. (wikipedia.org)
- For example, methylamine:L-glutamate N-methyltransferase would be the standard naming convention for the transferase methylamine-glutamate N-methyltransferase, where methylamine is the donor, L-glutamate is the acceptor, and methyltransferase is the EC category grouping. (wikipedia.org)
- This same action by the transferase can be illustrated as follows: methylamine + L-glutamate ⇌ {\displaystyle \rightleftharpoons } NH3 + N-methyl-L-glutamate However, other accepted names are more frequently used for transferases, and are often formed as "acceptor grouptransferase" or "donor grouptransferase. (wikipedia.org)
- The deduced crossover points between the group A gene cluster (red) donor and group C (green) recipient strains are shown. (cdc.gov)
- The relative sequence identities of the 3 different regions of progeny (bottom) gac cluster genes with the group A S. pyogenes donor (top) and group C S. equisimilis recipient (middle) are indicated. (cdc.gov)
- Transferases are enzymes transferring a group, for example, the methyl group or a glycosyl group, from one compound (generally regarded as donor) to another compound (generally regarded as acceptor). (bvsalud.org)
Biosynthetic2
Drugs2
- We are studying the biosynthesis mechanism of sulfur-modification and its regulation mechanisms in order to develop new drugs. (go.jp)
- Relevant of mutagenicity and clastogenici- angiosarcomas of the liver, which carcinogens discussed in this chap- ty, including the induction of sister are rare tumours, were identified in ter do not include pharmaceutical chromatid exchange (SCE), chro- humans, rats, and mice exposed to drugs classified in Group 1, which mosomal aberrations (CA), and mi- vinyl chloride. (who.int)
Polymerase1
- For example, RNA polymerase is the modern common name for what was formerly known as RNA nucleotidyltransferase, a kind of nucleotidyl transferase that transfers nucleotides to the 3' end of a growing RNA strand. (wikipedia.org)
Compounds1
- The metabolism of SAMe also results in the production of L-cysteine, an important amino acid used by the body to construct a family of sulfur-containing compounds of critical importance, including glutathione. (jarrow.com)
Protein4
- In a thermophilic bacteria, activated sulfur which bond to a sulfur-carrier protein TtuB [Fig. 2] is transferred to tRNA by a sulfur transferase. (go.jp)
- In the last steps of this process transfer of energy-conserving electrons beyond photosystem I (PSI) is performed by a small iron-sulphur protein ferredoxin (Fd). (nature.com)
- Average protein carbonyl concentrations were measured in patients grouped in 5-year age intervals (ranging from 56-60 to 86-90). (molvis.org)
- Preclinical and clinical pharmacodynamic assessment of L-778,123, a dual inhibitor of farnesyl:protein transferase and geranylgeranyl:protein transferase type-I. Mol Cancer Ther. (jefferson.edu)
Residues2
- A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. (wakehealth.edu)
- The coiled-coil structure of the bundle is stabilized by a network of S-aromatic interactions involving highly conserved sulfur-containing residues. (rcsb.org)
Antioxidant2
- For our research projects, we employ biochemical, biophysical, spectroscopic and structural biology approaches with *Populus trichocarpa* and *Arabidopsis thaliana* as model organisms to explore (i) the roles of the antioxidant/detoxification systems in the physiology of plants subject to environmental constraints and (ii) the maturation and roles of iron-sulfur proteins in plant organelles. (hal.science)
- A sulfur-containing amino acid compound that is a precursor to glutathione, giving it powerful antioxidant and detoxification properties. (seekinghealth.com)
Chemicals2
- All of the chemicals discussed of this chemical was raised to carci- lung and the nasal cavity were iden- here are IARC Group 1 agents and nogenic to humans (Group 1) based tified as target organs in humans as such can be characterized as on strong mechanistic evidence and rats, respectively. (who.int)
- Among this group of chemicals, tected in epidemiological studies of IARC evaluations of the carcinogen- there is remarkable concordance in exposed workers. (who.int)
Acceptor2
- For example, a DNA methyltransferase is a transferase that catalyzes the transfer of a methyl group to a DNA acceptor. (wikipedia.org)
- These have also been subdivided according to the acceptor group. (wakehealth.edu)
Metabolic1
- The donation of methyl groups affects the proper function of many metabolic processes, including brain function, energy production and DNA metabolism. (jarrow.com)
Zinc2
- The pterin moiety of CH3-H4PteGlu5 is stacked with Trp567, enabling the N5-methyl group to protrude in the direction of the zinc atom. (rcsb.org)
- Comparison of AtMetE structures reveals that the addition of Hcy does not lead to a direct coordination of the sulfur atom with zinc but to a reorganization of the zinc binding site with a stronger coordination to Cys649, Cys733, and a water molecule. (rcsb.org)
Activity2
- Group" would be the functional group transferred as a result of transferase activity. (wikipedia.org)
- Earliest discoveries of transferase activity occurred in other classifications of enzymes, including beta-galactosidase, protease, and acid/base phosphatase. (wikipedia.org)
Atom1
- Cobalamin-independent methionine synthase (MetE) catalyzes the synthesis of methionine by a direct transfer of the methyl group of N5-methyltetrahydrofolate (CH3-H2PteGlun) to the sulfur atom of homocysteine (Hcy). (rcsb.org)
Cytochrome1
- Fd acts simultaneously as a bottleneck and as a hub which distributes high-energy electrons to a multitude of enzymes, which include nitrite reductase, sulphite reductase, fatty acid desaturase, glutamine-2-oxoglutarate amino transferase (GOGAT), redox complexes such as cytochrome b 6 /f for cyclic electron transport (CET) and thioredoxins 2 . (nature.com)
Modifications1
- Among them, sulfur modifications of tRNA are important for tRNA functions, such as codon recognition and stabilization of the tertiary structure [Fig. 1]. (go.jp)
Mechanism1
- Another example of historical significance relating to transferase is the discovery of the mechanism of catecholamine breakdown by catechol-O-methyltransferase. (wikipedia.org)
Carbohydrate1
- The 3 genes required for inclusion of the immunodominant N- acetylglucosamine side chain within the group A carbohydrate ( gacI, gacJ , and gacK ) are shown in red. (cdc.gov)
Molecule1
- In this context, the intervention of the TRX and glutathione (GSH)/GRX reducing systems in the sulfur signaling/trafficking pathways is examined as both the TRX and GSH/GRX systems might modulate STR function and in particular be central to the formation of hydrogen sulfide, a molecule susceptible to trigger redox signalling cascades in several physiological situations. (hal.science)
Transfer1
- Transamination, or the transfer of an amine (or NH2) group from an amino acid to a keto acid by an aminotransferase (also known as a "transaminase"), was first noted in 1930 by Dorothy M. Needham, after observing the disappearance of glutamic acid added to pigeon breast muscle. (wikipedia.org)
Identification1
- The current work is centered on the structure-function analysis of specific classes of glutathione transferases, focusing in particular on the isolation and identification of physiological substrates explaining their implication in biotic or abiotic stress responses. (hal.science)
Important2
- Some of the most important discoveries relating to transferases occurred as early as the 1930s. (wikipedia.org)
- NAC (N-acetylcysteine) is an important sulfur-containing amino acid. (seekinghealth.com)
Large1
- Johnson (Athens, USA), O. Keech (Umea), A. Meyer (Bonn), U. Mühlenhoff (Marburg), C. Remacle (Liège), F. Vignols (BPMP Montpellier)** - **Structure-Function analysis of glutathione transferases** Glutathione transferases (GSTs) constitute large multigenic families of more than 50 genes in terrestrial plants. (hal.science)
Major1
- This graph shows the total number of publications written about "Sulfur Group Transferases" by people in UAMS Profiles by year, and whether "Sulfur Group Transferases" was a major or minor topic of these publications. (uams.edu)
Functional2
- In this case, an amino acid chain is the functional group transferred by a peptidyl transferase. (wikipedia.org)
- Prior to the realization that individual enzymes were capable of such a task, it was believed that two or more enzymes enacted functional group transfers. (wikipedia.org)
Classes1
- There are 6 main classes of enzymes: oxydoreductases (E.C.1), transferases (E.C.2), hydrolase (E.C.3), lyases (E.C.4), isomerases (E.C.5) and ligases (E.C.6). (proteogenix.science)
Shown1
- In 1953, the enzyme UDP-glucose pyrophosphorylase was shown to be a transferase, when it was found that it could reversibly produce UTP and G1P from UDP-glucose and an organic pyrophosphate. (wikipedia.org)
Structure1
- Its unique chemical structure contains an outer sulfur group. (seekinghealth.com)