24740-88-3

Usage

Definition

ChEBI: A 4-oxohex-2-enedioic acid with a Z-configuration.

InChI:InChI=1/C6H6O5/c7-4(3-6(10)11)1-2-5(8)9/h1-2H,3H2,(H,8,9)(H,10,11)/b2-1-

Upstream product

• 89-64-5 p-chloro-o-nitrophenol 
• 3374-46-7 (Z)-5-oxo-2,5-dihydrofuran-2-ylideneacetic acid 
• 123-31-9 hydroquinone 
• 3374-46-7 (2E)-2-(5-oxo-2(5H)-furanylidene)acetic acid 
• 615-67-8 chloro-p-hydroquinone 
• 583-69-7 2-bromobenzene-1,4-diol 

Relevant academic research and scientific papers

Substrate-Induced Conformational Change and Isomerase Activity of Dienelactone Hydrolase and its Site-Specific Mutants

Studies of the interactions of dienelactone hydrolase (DLH) and its mutants with both E and Z dienelactone substrates show that the enzyme exhibits two different conformational responses specific for hydrolysis of each of its substrate isomers. DLH facili

Biodegradation of aromatic hydrocarbons and phenols by bacteria isolated from caspian waters and soils

Experimental studies have been carried out on the degradability of monoaromatic hydrocarbons (benzene, toluene, and ethylbenzene) and phenols (phenol, pyrocatechol, hydroquinone, tetrachloropyro- catechol) by bacteria isolated from coastal waters and soil

Substrate specificity of Sphingobium chlorophenolicum 2,6- dichlorohydroquinone 1,2-dioxygenase

PcpA is an aromatic ring-cleaving dioxygenase that is homologous to the well-characterized Fe(II)-dependent catechol extradiol dioxygenases. This enzyme catalyzes the oxidative cleavage of 2,6-dichlorohydroquinone in the catabolism of pentachlorophenol by Sphingobium chlorophenolicum ATCC 39723. 1H NMR and steady-state kinetics were used to determine the regiospecificity of ring cleavage and the substrate specificity of the enzyme. PcpA exhibits a high degree of substrate specificity for 2,6-disubstituted hydroquinones, with halogens greatly preferred at those positions. Notably, the kcat app/KmAapp of 2,6-dichlorohydroquinone is ～40-fold higher than that of 2,6-dimethylhydroquinone. The asymmetric substrate 2-chloro-6-methylhydroquinone yields a mixture of 1,2- and 1,6-cleavage products. These two modes of cleavage have different K mO2app values (21 and 260 μM, respectively), consistent with a mechanism in which the substrate binds in two catalytically productive orientations. In contrast, monosubstituted hydroquinones show a limited amount of ring cleavage but rapidly inactivate the enzyme in an O2-dependent fashion, suggesting that oxidation of the Fe(II) may be the cause. Potent inhibitors of PcpA include ortho-disubstituted phenols and 3-bromocatechol. 2,6-Dibromophenol is the strongest competitive inhibitor, consistent with PcpA's substrate specificity. Several factors that could yield this specificity for halogen substituents are discussed. Interestingly, 3-bromocatechol also inactivates the enzyme, while 2,6-dihalophenols do not, indicating a requirement for two hydroxyl groups for ring cleavage and for enzyme inactivation. These results provide mechanistic insights into the hydroquinone dioxygenases.

Site-directed mutagenesis of dienelactone hydrolase produces dienelactone isomerase

Replacing the active site Cys-123 of dienelactone hydrolase with Ser completely changes the catalysis displayed by the protein, from hydrolysis of the substrate E- and Z-dienelactones to maleylacetate by the native enzyme, to interconversion of the substr