... carbon-carbon double bond isomerases MeSH D08.811.399.475.400.700 - steroid isomerases MeSH D08.811.399.475.800 - sulfur-sulfur ... bond isomerases MeSH D08.811.399.475.800.550 - protein disulfide-isomerase MeSH D08.811.399.475.900 - thromboxane-a synthase ... glucose-6-phosphate isomerase MeSH D08.811.399.475.200.550 - mannose-6-phosphate isomerase MeSH D08.811.399.475.200.662 - ... carbon-nitrogen ligases with glutamine as amide-n-donor MeSH D08.811.464.259.400.300 - carbamoyl-phosphate synthase (glutamine- ...
KSI catalyzes the rearrangement of a carbon-carbon double bond in ketosteroids through an enolate intermediate at a diffusion- ... steroid isomerase, Δ5-ketosteroid isomerase, Δ5(or Δ4)-3-keto steroid isomerase, Δ5-steroid isomerase, 3-oxosteroid isomerase, ... 3-ketosteroid isomerase just transfers a double bond at Δ5 of 3-ketosteroid to Δ4. A Δ5-3-ketosteroid isomerase-disrupted ... which lacks a double bond at Δ5, indicating that C. testosteroni KSI is responsible for transfer of the double bond from Δ5 to ...
... or trans-double bonds of coenzyme A (CoA) bound fatty acids at gamma-carbon (position 3) to trans double bonds at beta-carbon ( ... The double bond serves as the target of oxidation and carbon-to-carbon bond cleavage, thereby shortening the fatty acid chain. ... Since the key step in the degradation of fatty acids with double bonds at even-numbered carbon positions also produces 3-trans- ... isomerase, 3,2-trans-enoyl-CoA isomerase, ∆3(cis),∆2(trans)-enoyl-CoA isomerase, or acetylene-allene isomerase, is an enzyme ...
... thus breaking the double bond and allowing rotation around the single bond. 4-maleylacetoacetate is converted to 4- ... helix dipole of alpha 1 of the enzyme stabilize the thiolate form of glutathione which activates it to attack the alpha carbon ... The systematic name of this enzyme class is 4-maleylacetoacetate cis-trans-isomerase. 4-Maleylacetoacetate isomerase is an ... 4-fumarylacetoacetate This enzyme belongs to the family of isomerases, specifically cis-trans isomerases. ...
The adjacent carbon, C2, is deprotonated from the opposite face to yield a double bond. In effect, the double bond is shifted ... In this isomerization reaction a stable carbon-carbon double bond is rearranged top create a highly electrophilic allylic ... IPP isomerase catalyzes this reaction by the stereoselective antarafacial transposition of a single proton. The double bond is ... The C3-C4 bond rotates and Glu357 (assisted by His388) depronates C2 to form a double bond between C1 and C2. A cis-endiol ...
... and fumaric acid do not spontaneously interconvert because rotation around a carbon carbon double bond is not ... Some bacteria produce the enzyme maleate isomerase, which is used by bacteria in nicotinate metabolism. This enzyme catalyses ... Reversible addition (of H+) leads to free rotation about the central C-C bond and formation of the more stable and less soluble ... Two normal hydrogen bonds are observed, one intramolecular and one intermolecular. Crystallographic analysis shows that the ...
... loss of proton from carbon 4 leads to the formation of a double bond C3-C4; consequently the 3-O-carbonyl atom will attach to ... IPP is isomerized to the allylic ester dimethylallyl pyrophosphate (DMAPP) by IPP isomerase. Through a multi-step process, ... Aucubin was found to protect against liver damage induced by carbon tetrachloride or alpha-amanitin in mice and rats when 80 mg ... Aucubin has 10 carbons with the C11 carbon missing. The stereochemical configurations at C5 and C9 lead to cis fused rings, ...
3-2trans-enoyl-CoA isomerase (or dodecenoyl-CoA isomerise; EC 5.3.3.8), which shifts the 3-double bond of the intermediates of ... while others have been implicated in carbon-carbon bond formation and cleavage as well as the hydrolysis of thioesters. However ... Dienoyl-CoA isomerase, which catalyses the isomerisation of 3-trans,5-cis-dienoyl-CoA to 2-trans,4-trans-dienoyl-CoA. ... This is accomplished by two structurally conserved peptidic NH groups that provide hydrogen bonds to the carbonyl moieties of ...
To summarize: Odd-numbered double bonds are handled by the isomerase. Even-numbered double bonds by the reductase (which ... The bicarbonate ion's carbon is added to the middle carbon of propionyl-CoA, forming a D-methylmalonyl-CoA. However, the D ... If the acyl CoA contains a cis-Δ3 bond, then cis-Δ3-Enoyl CoA isomerase will convert the bond to a trans-Δ2 bond, which is a ... A long-chain fatty acid is dehydrogenated to create a trans double bond between C2 and C3. This is catalyzed by acyl CoA ...
This conversion introduces two additional double bonds at positions 11 and 11' of the carbon chain and isomerizes two adjacent ... This reaction starts a biochemical pathway involving three further enzymes (zeta-carotene isomerase, zeta-carotene desaturase ... introduce two double bonds into their colorless substrate phytoene by dehydrogenation and isomerize two additional double bonds ... already existing double bonds at positions 9 and 9' from trans to cis. The electrons involved in the reaction are subsequently ...
... with loss of the double bond in the dioxygen unit and bonds to iron and the alpha carbon of 2-oxoglutarate. Subsequent ... This subunit and protein disulphide isomerase are products of the same gene". The EMBO Journal. 6 (3): 643-9. doi:10.1002/j. ... This subunit is identical to the enzyme known as protein disulfide isomerase. Prolyl hydroxylase catalyzes the formation of ... "Site-directed mutagenesis of human protein disulphide isomerase: effect on the assembly, activity and endoplasmic reticulum ...
... usually through an attack of an electronegative atom on the carbonyl carbon, breaking the carbonyl double bond and forming a ... Both of these mechanisms for lowering the activation energy have been observed in peptidyl prolyl isomerases (PPIases), which ... forms an isopeptide bond, which is not a peptide bond) and glutathione synthetase (forms a peptide bond). A peptide bond can be ... It can also be called a eupeptide bond to distinguish it from an isopeptide bond, which is another type of amide bond between ...
It is responsible for catalyzing cis-trans isomerization of the C2-C3 double bond in maleate to produce fumarate, which is a ... Pro14 and Val84 make van der Waals interactions with the C2 and C3 carbon atoms of the maleate. The mechanism of maleate ... For example, maleate isomerase from Pseudomonas putida S16 uses Asn17 and Asn169 form hydrogen bonds with the carboxylate group ... The newly formed C2-C3 single bond is then rotated, with Cys76S-C2 bond dissociated, and C3 atom of the maleate deprotonated by ...
In particular, this enzyme contributes to breaking the double bonds at all even-numbered positions, and some double bonds at ... DECR is the second such enzyme (the others being enoyl CoA isomerase and dienoyl CoA isomerase) and is the rate limiting step ... Additionally, at one end of the active site there is a flexible loop that provides sufficient room for long carbon chains. This ... The electrons from the Cγ-Cδ double bond move over to the Cβ-Cγ position, and those from the Cα-Cβ form an enolate. In the ...
Because phosphoenolpyruvate mutase has the unusual ability to form a new carbon-phosphorus bond, it is essential to the ... A double phosphoryl transfer mechanism was proposed on the basis of this study: this would involve breakage of PEP's phosphorus ... This enzyme belongs to the family of isomerases, specifically the phosphotransferases (phosphomutases), which transfer ... isolation of the enzyme responsible for the formation of a carbon-phosphorus bond". Nature. 335 (6189): 457-458. Bibcode: ...
The free electron pair adds to the double bond of IPP, also isomerizing IPP so that the product is an allylic diphosphate. Thus ... Isopentenyl diphosphate isomerase converts the latter to the less stable dimethylallyl diphosphate. Farnesyl diphosphate ... All parts of the carbon skeleton comes from IPP. Then an enzyme prenyl transferase/farnesyl diphosphate synthase binds IPP, ... Labelling Pattern from [1-14+C]-Propionate through Degradation to Single Carbon Atom Derivatives". Helvetica Chimica Acta. 58 ( ...
... the two carboxyl groups on the double bond are cis). The carbon atom from which the hydrogen is removed is the one that came ... The iron-responsive element-binding protein (IRE-BP) and 3-isopropylmalate dehydratase (α-isopropylmalate isomerase; EC 4.2. ... creating a double bond between C2 and C3, and forming the so-called cis-aconitate intermediate ( ... and the protonated serine is deprotonated by the cis-aconitate double bond to complete the hydration, producing isocitrate. ...
Steric course of decarboxylation of 5-pyrophosphomevalonate and of the carbon to carbon bond formation in the biosynthesis of ... The removal of the pro-R proton from C2 forms the C2-C3 double bond of DMAPP. Crystallographic studies have observed that the ... Isopentenyl pyrophosphate isomerase (EC 5.3.3.2, IPP isomerase), also known as Isopentenyl-diphosphate delta isomerase, is an ... methylbutenylpyrophosphate isomerase, and isopentenylpyrophosphate isomerase. IPP isomerase catalyzes the isomerization of IPP ...
The double bond of cycloartenol (compound 7 in diagram) is methylated by SAM to give a carbocation that undergoes a hydride ... This step is catalyzed by sterol C-14 demethylase (E4), sterol Δ14-reductase (E5), and sterol Δ8-Δ7-isomerase (E6). The last ... Fermentation digests the entire aliphatic side-chain at carbon 17 to afford a mixture of 17-keto products including ... The last step of the synthesis is deprotection of the β-ring double bond of 5 with p-TsOH, aqueous dioxane, and heat (80 °C) to ...
EPA is a carboxylic acid with a 20-carbon chain and five cis double bonds; the first double bond is located at the third carbon ... dehydratase/2-trans 3-cos isomerase (DH/2,3I), dehydratase/2-trans, and 2-cis isomerase(DH/2,2I). The biosynthesis of EPA ... The final step is the NADPH-dependent reduction of a double bond in trans-2-enoly-ACP via ER enzyme activity. The process is ... The molecule basis of the enzymes will dictate where the double bond is formed on the resulting molecule. Here is an overview ...
These observed phenomena are due to the trans-cis isomerization of the vinyl trans double bond in the p-coumaric acid. ... "Structural Coupling Throughout the Active Site Hydrogen Bond Networks of Ketosteroid Isomerase and Photoactive Yellow Protein ... noted by observing the crystal structure of p-coumaric acid bound by PYP that the hydroxyl group connected to the C4 carbon of ... This was due to abnormally short hydrogen bonding lengths observed in the protein crystal structure. Hydrogen bonds in proteins ...
Natural rubber consists of polyisoprene in which the double bonds are cis. Some plants produce a polyisoprene with trans double ... C5 IPP and C5 DMAPP are the end-products in either pathway and are the precursors of terpenoids with various carbon numbers ( ... IPP is isomerized to DMAPP by the enzyme isopentenyl pyrophosphate isomerase. IPP and DMAPP condense to give geranyl ... bonds, known as gutta-percha. Norisoprenoids, characterized by the shortening of a chain or ring by the removal of a methylene ...
... the enzyme does not form or break a carbon-sulfur bond. Rather, the enzyme shifts two hydrogen atoms from one carbon atom of ... The ene means that a double bond has formed between C2 and C1, from the electrons left behind by the abstraction of the ... Methylglyoxal is formed spontaneously from dihydroxyacetone phosphate, enzymatically by triosephosphate isomerase and ... the extra electron on the oxygen of C1 could reform the double bond of the carbonyl, thus giving the final product. An ...
The carboxylate side chain of Asp-295 hydrogen bonds with the hydroxyl groups at C-2 and C-3 of the glucosyl residue. This ... It has been shown in multiple experiments that the enzyme catalyzes this conversion by a double displacement mechanism. The ... Finally, phosphorylation of the glucosyl residue at C-1 forms a transient positive charge on the glucosyl carbon, promoting ... fructose-6-phosphate and glucose-6-phosphate can be interconverted in the glycolytic pathway by phosphohexose isomerase. The ...
... to the rearranged carbon radical center thereby forming a peroxy radical(-OO·) bond to that carbon reduction of the peroxy ... as opposed to the 4 double bond-containing arachidonic acid metabolites. The enzyme, when acting in series with other ... Rather, its primary activity is as a hydroperoxide isomerase that metabolizes certain unsaturated hydroperoxy fatty acids to ... from a bisallylic methylene carbon to form a fatty acid radical at that carbon rearrangement of the radical to another carbon ...
KduI/IolB isomerase family - kilobase - kinase - Klenow fragment - Knock-down - knock-out - knock-out experiment - knockout - ... double helix - downstream (DNA) - downstream (transduction) - drimenol cyclase- ds - duplex - E. coli - Ecotin - EIF-W2 protein ... carbon-monoxide dehydrogenase (cytochrome b-561) - carboxyl terminus - carcinoma - carnitine dehydratase - carrier - carveol ... peptide bond - phage - phagemid - phenotype - phenylacetaldoxime dehydratase - PhIP-Seq - phosphatase, alkaline - ...
... with the presence of the catechol moiety on ring B and the presence of a hydroxyl group activating the double bond on ring C. ... Chalcone is then isomerized to naringenin by chalcone isomerase which is oxidized to eriodictyol by flavonoid 3′-hydroxylase ... with a hydroxyl group on carbon 3. The A ring is similar to a resorcinol moiety while the B ring is similar to a catechol ...
The central double bond of this tri-cis-ζ-carotene is isomerized by the zeta-carotene isomerase Z-ISO and the resulting 9,9'-di ... Carotenes typically contain only carbon and hydrogen, i.e., they are hydrocarbons. Prominent members include α-carotene, β- ... introduces two additional double bonds into 15-cis-phytoene by dehydrogenation and isomerizes two of its existing double bonds ... This again introduces two double bonds, resulting in 7,9,7',9'-tetra-cis-lycopene. CRTISO, a carotenoid isomerase, is needed to ...
The 2-trans double bond may then be reduced via ER utilizing NADPH + H+ (FAS pathway continuation) or isomerized via DH/I ... In terms of organic carbon sources, thraustochytrids are capable of harnessing organic carbon compounds like maltose, fructose ... This was accomplished via overexpressing heterologous xylulose kinase and endogenous xylose isomerase. A European patent has ... H+ and the subsequent product is dehydrated via a DH or DH/I dehydratase to produce an acyl chain with a 2-trans double bond ( ...
dA molecules are bonded to the tails of each fragment, allowing the dT of the ribose-seq adaptor to bind it's corresponding dA ... During alkali treatment, double stranded DNA (dsDNA) is treated with sodium hydroxide, a strong base, to denature the dsDNA and ... Additional rNMP removal methods include incisions that are mediated by the isomerase enzyme, topoisomerase I. If not removed ... and a five-carbon sugar (ribose in ribonucleotides and deoxyribose in deoxyribonucleotides). While ribonucleotides are ...