Enzymatic Transformations; 61. Preparation of Enantiopure Trifluoromethyl-Substituted Aromatic Epoxides and Vicinal Diols using theAspergillus niger Epoxide Hydrolase-Catalysed Resolution

2006 ◽  
Vol 348 (10-11) ◽  
pp. 1165-1169 ◽  
Author(s):  
Justine Deregnaucourt ◽  
Alain Archelas ◽  
Fabien Barbirato ◽  
Jean-Marc Paris ◽  
Roland Furstoss
2000 ◽  
Vol 28 (6) ◽  
pp. 855-856 ◽  
Author(s):  
J. Edqvist ◽  
I. Farbos

In Euphorbia lagascae the major fatty acid in triacylglycerol is the epoxidated fatty acid vernolic acid (cis- 12-epoxyoctadeca-cis-9-enoic acid). The enzymic reactions occurring during the catabolism of epoxidated fatty acids during germination are not known, but it seems likely that the degradation requires the activity of an epoxide hydrolase. Epoxide hydrolases are a group of functionally related enzymes that catalyse the cofactor-independent hydrolysis of epoxides to their corresponding vicinal diols by the addition of a water molecule. Here we report the cloning and characterization of an epoxide hydrolase gene from E. lagascae. The structure of the gene is unusual since it lacks introns. A detailed investigation of the transcription pattern of the epoxide hydrolase gene shows that the gene is induced during germination. We have used in situ hybridization to identify in which tissues the gene is expressed during germination. We speculate that this epoxide hydrolase enzyme is involved in the catabolism of epoxidated fatty acids during germination of E. lagascae seeds.


2008 ◽  
Vol 35 (11) ◽  
pp. 1112 ◽  
Author(s):  
C. P. Wijekoon ◽  
P. H. Goodwin ◽  
T. Hsiang

Epoxide hydrolase hydrates epoxides to vicinal diols in the phyto-oxylipin peroxygenase pathway resulting in the production of epoxy alcohols, dihydrodiols, triols and epoxides, including many lipid epoxides associated with resistance. Two epoxide hydrolase genes from Nicotiana benthamiana L., NbEH1.1 and NbEH1.2, were amplified from coding DNA of leaves during a susceptible response to the hemibiotrophic pathogens, Colletotrichum destructivum O’Gara, Colletotrichum orbiculare Berk. and Mont. von Arx. or Pseudomonas syringae pv. tabaci Wolf and Foster, or the hypersensitive resistance response to P. syringae pv. tabaci expressing avrPto. Increases in expression of NbEH1.1 generally occurred during the late biotrophic and necrotrophic stages in the susceptible responses and before the hypersensitive response. NbEH1.2 expression was not significantly induced by C. orbiculare but was induced by C. destructivum, P. syringae pv. tabaci and P. syringae pv. tabaci expressing avrPto, although to a lesser degree than NbEH1.1. Virus-induced gene silencing of NbEH1.1 delayed the appearance of lesions for C. destructivum, reduced populations of P. syringae pv. tabaci and increased populations of P. syringae pv. tabaci expressing avrPto. The importance of epoxide hydrolase during pathogen attack may be related to its roles in detoxification, signalling, or metabolism of antimicrobial compounds.


2017 ◽  
Vol 15 (41) ◽  
pp. 8827-8835 ◽  
Author(s):  
Eila Serrano-Hervás ◽  
Marc Garcia-Borràs ◽  
Sílvia Osuna

Epoxide hydrolase (EH) enzymes catalyze the hydration of racemic epoxides to yield their corresponding vicinal diols. In this work, the Bacillus megaterium epoxide hydrolase (BmEH)-mediated hydrolysis of racemic styrene oxide (rac-SO) and its para-nitro styrene oxide (rac-p-NSO) derivative are computationally investigated using density functional theory (DFT).


2020 ◽  
Author(s):  
Alexis Wolfel ◽  
Cecilia Inés Alvarez Igarzabal ◽  
Marcelo Ricardo Romero

<p>Design of materials with novel sensitivities and smart behaviour is important for the development of smart systems with automated responsiveness. We have recently reported the synthesis of hydrogels, cross-linked by <i>N,N'</i>-diallyltartardiamide (DAT). The covalent DAT-crosslinking points have vicinal diols which can be easily cleaved with periodate, generating valuable a-oxo-aldehyde functional groups, useful for further chemical modification. Based on those findings, we envisioned that a self-healable hydrogel could be obtained by incorporation of primary amino functional groups, from <a>2-aminoethyl methacrylate </a>hydrochloride (AEMA), coexisting with DAT into the same network. The a-oxo-aldehyde groups generated after the reaction with periodate would arise in the immediate environment of amine groups to form imine cross-links. For this purpose, DAT-crosslinked hydrogels were synthesized and carefully characterized. The cleavage of DAT-crosslinks with periodate promoted changes in the mechanical and swelling properties of the materials. As expected, a self-healing behavior was observed, based on the spontaneous formation of imine covalent bonds. In addition, we surprisingly found a combination of fast vicinal diols cleavage and a low speed self-crosslinking reaction by imine formation. Consequently, it was found a time-window in which a periodate-treated polymer was obtained in a transient liquid state, which can be exploited to choose the final shape of the material, before automated gelling. The singular properties attained on these hydrogels could be useful for developing sensors, actuators, among other smart systems.</p>


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