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Thioredoxin Domain
Thioredoxins are small disulfide-containing redox proteins that have been found in all the kingdoms of living organisms. Thioredoxin serves as a general protein disulfide oxidoreductase. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of 2 cysteine thiol groups to a disulfide, accompanied by the transfer of 2 electrons and 2 protons. The net result is the covalent interconversion of a disulfide and a dithiol. TR-S2 + NADPH + H+ -> TR-(SH)2 + NADP+ (1) trx-S2 + TR-(SH)2 -> trx-(SH)2 + TR-S2 (2) Protein-S2 + trx-(SH)2 -> Protein-(SH)2 + trx-S2 (3) In the NADPH-dependent protein disulfide reduction, thioredoxin reductase (TR) catalyses reduction of oxidised thioredoxin (trx) by NADPH using FAD and its redox-active disulfide (steps 1 and 2). Reduced thioredoxin then directly reduces the disulfide in the substrate protein (step 3). Protein disulfide isomerase (PDI), a resident foldase of the endoplasmic reticulum, is a multi-functional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Disulfide Oxidoreductase
In enzymology, a protein-disulfide reductase () is an enzyme that catalyzes the chemical reaction :protein dithiol + NAD(P)+ \rightleftharpoons protein disulfide + NAD(P)H + H+ The 3 substrates of this enzyme are protein dithiol, NAD+, and NADP+, whereas its 4 products are protein disulfide, NADH, NADPH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is protein-dithiol:NAD(P)+ oxidoreductase. Other names in common use include protein disulphide reductase, insulin-glutathione transhydrogenase, disulfide reductase, and NAD(P)H2:protein-disulfide oxidoreductase. Structural studies As of late 2007, 8 structures A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-proline
Proline (symbol Pro or P) is an organic acid classed as a proteinogenic amino acid (used in the biosynthesis of proteins), although it does not contain the amino group but is rather a secondary amine. The secondary amine nitrogen is in the protonated form (NH2+) under biological conditions, while the carboxyl group is in the deprotonated −COO− form. The "side chain" from the α carbon connects to the nitrogen forming a pyrrolidine loop, classifying it as a aliphatic amino acid. It is non-essential in humans, meaning the body can synthesize it from the non-essential amino acid L-glutamate. It is encoded by all the codons starting with CC (CCU, CCC, CCA, and CCG). Proline is the only proteinogenic secondary amino acid which is a secondary amine, as the nitrogen atom is attached both to the α-carbon and to a chain of three carbons that together form a five-membered ring. History and etymology Proline was first isolated in 1900 by Richard Willstätter who obtained the amino a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PDIA3
Protein disulfide-isomerase A3 (PDIA3), also known as glucose-regulated protein, 58-kD (GRP58), is an isomerase enzyme. This protein localizes to the endoplasmic reticulum (ER) and interacts with lectin chaperones calreticulin and calnexin (CNX) to modulate folding of newly synthesized glycoproteins. It is thought that complexes of lectins and this protein mediate protein folding by promoting formation of disulfide bonds in their glycoprotein substrates. Structure The PDIA3 protein consists of four thioredoxin-like domains: a, b, b′, and a′. The a and a′ domains have Cys-Gly-His-Cys active site motifs (C57-G58-H59-C60 and C406-G407-H408-C409) and are catalytically active. The bb′ domains contain a CNX binding site, which is composed of positively charged, highly conserved residues (K214, K274, and R282) that interact with the negatively charged residues of the CNX P domain. The b′ domain comprises the majority of the binding site, but the β4-β5 loop of the b domain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PDIA2
Protein disulfide isomerase family A member 2 is a protein that in humans is encoded by the PDIA2 gene. Function This gene encodes a member of the Protein disulfide-isomerase, disulfide isomerase (PDI) family of endoplasmic reticulum (ER) proteins that catalyze protein folding and thiol-disulfide interchange reactions. The encoded protein has an N-terminal ER-signal sequence, two catalytically active thioredoxin (TRX) domains, two TRX-like domains and a C-terminal ER-retention sequence. The protein plays a role in the folding of nascent proteins in the endoplasmic reticulum by forming disulfide bonds through its thiol isomerase, oxidase, and reductase activity. The encoded protein also possesses estradiol-binding activity and can modulate intracellular estradiol levels. [provided by RefSeq, Sep 2017]. References Further reading * * * * * * * * * {{gene-16-stub Endoplasmic reticulum resident proteins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P4HB
Protein disulfide-isomerase, also known as the beta- subunit of prolyl 4-hydroxylase (P4HB), is an enzyme that in humans encoded by the ''P4HB'' gene. The human ''P4HB'' gene is localized in chromosome 17q25. Unlike other prolyl 4-hydroxylase family proteins, this protein is multifunctional and acts as an oxidoreductase for disulfide formation, breakage, and isomerization. The activity of P4HB is tightly regulated. Both dimer dissociation and substrate binding are likely to enhance its enzymatic activity during the catalysis process. Structure P4HB has four thioredoxin domains (a, b, b’, and a’), with two CGHC active sites in the a and a’ domains. In both the reduced and oxidized state, these domains are arranged as a horseshoe shape. In reduced P4HB, domains a, b, and b' are in the same plane, while domain a' twists out at a ∼45° angle. When oxidized, the four domains stay in the same plane, and the distance between the active sites is larger than that in the reduced st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GLRX3
Glutaredoxin-3 is a protein that in humans is encoded by the ''GLRX3'' gene. Interactions GLRX3 has been shown to interact with PRKCQ Protein kinase C theta (PKC-θ) is an enzyme that in humans is encoded by the ''PRKCQ'' gene. PKC-θ, a member of serine/threonine kinases, is mainly expressed in hematopoietic cells with high levels in platelets and T lymphocytes, where plays a r .... References Further reading * * * * * * * External links * {{gene-10-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNAJC10
DnaJ homolog subfamily C member 10 is a protein that in humans is encoded by the ''DNAJC10'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b .... References Further reading * * * * * * * * External links PDBe-KBprovides an overview of all the structure information available in the PDB for Mouse DnaJ homolog subfamily C member 10 (DNAJC10) Heat shock proteins Endoplasmic reticulum resident proteins {{gene-2-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutathione Transferase
Glutathione ''S''-transferases (GSTs), previously known as ligandins, are a family of eukaryotic and prokaryotic phase II metabolic isozymes best known for their ability to catalyze the conjugation of the reduced form of glutathione (GSH) to xenobiotic substrates for the purpose of detoxification. The GST family consists of three superfamilies: the cytosolic, mitochondrial, and microsomal—also known as MAPEG—proteins. Members of the GST superfamily are extremely diverse in amino acid sequence, and a large fraction of the sequences deposited in public databases are of unknown function. The Enzyme Function Initiative (EFI) is using GSTs as a model superfamily to identify new GST functions. GSTs can constitute up to 10% of cytosolic protein in some mammalian organs. GSTs catalyse the conjugation of GSH—via a sulfhydryl group—to electrophilic centers on a wide variety of substrates in order to make the compounds more water-soluble. This activity detoxifies endogenous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
