Any feedback?
Literature summary for 3.3.2.9 extracted from
- Characterization of an epoxide hydrolase from the Florida red tide dinoflagellate, Karenia brevis (2016), Phytochemistry, 122, 11-21 .
Cloned(Commentary)
| Cloned (Comment) | Organism |
|---|---|
| screening of different Karenia brevis transcriptome libraries and enzyme cloning, recombinant expression of His-tagged mEH isozymes in Escherichia coli | Karenia brevis |
Inhibitors
| Inhibitors | Comment | Organism | Structure |
|---|---|---|---|
| beta-dimethylstyrene oxide | - |
Karenia brevis |  |
| cis-beta-methylstyrene oxide | - |
Karenia brevis | |
| additional information | no inhibition by cis-2,3-epoxybutane and 2,3-dimethyl-2,3-epoxybutane | Karenia brevis | |
| trans-beta-methylstyrene oxide | - |
Karenia brevis | |
Localization
| Localization | Comment | Organism | GeneOntology No. | Textmining |
|---|---|---|---|---|
| microsome | the N-terminal domains of mEHs are characterized by a microsomal domain which may or may not be preceded by an N-terminal membrane anchor, it is absent in the two Karenia brevis mEHs | Karenia brevis | - |
- |
Organism
| Organism | UniProt | Comment | Textmining |
|---|---|---|---|
| Karenia brevis | - |
- |
- |
Purification (Commentary)
| Purification (Comment) | Organism |
|---|---|
| recombinant His-tagged mEH isozymes from Escherichia coli by nickel affinity chromatography and dialysis | Karenia brevis |
Substrates and Products (Substrate)
| Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
|---|---|---|---|---|---|---|
| cyano(2-methoxynaphthalen-6-yl)methyl trans-2-(3-propyloxiran-2-yl)acetate + H2O | - |
Karenia brevis | ? | - |
? | |
| cyano-(6-methoxynaphthalen-2-yl)methyl trans-2-pentenylacetate + H2O | prepared from trans-styrylacetic acid and 7-methoxy-2-naphthaldehyde. Enzyme EH catalyzed hydrolysis of the epoxide substrate produces an intermediate diol which lactonizes to release a fluorescent reporter after hydrolysis of the intermediate cyanohydrin | Karenia brevis | ? | - |
? | |
| additional information | the enzyme has the potential to catalyze the critical endo-tet cyclization of epoxy alcohols via a endo-tet cyclization, mechanism, overview. Reaction of polyepoxide pre-momensin to momensin, a polyether, or of another polyepoxide to brevetoxin B | Karenia brevis | ? | - |
? | |
| okadaic acid + H2O | - |
Karenia brevis | ? | - |
? | |
| trans-4,5-epoxy-hexanol | exo-tet cyclization reaction | Karenia brevis | 1-(tetrahydrofuran-2-yl)ethanol | - |
? | |
| trans-4,5-epoxy-hexanol | endo-tet cyclization reaction | Karenia brevis | 2-methyltetrahydro-2H-pyran-3-ol | - |
? | |
Synonyms
| Synonyms | Comment | Organism |
|---|---|---|
| alpha,beta fold epoxide hydrolase | - |
Karenia brevis |
| alpha,beta-fold type EH | - |
Karenia brevis |
| EH1 | - |
Karenia brevis |
| EH2 | - |
Karenia brevis |
| epoxide hydrolase | - |
Karenia brevis |
| mEH | - |
Karenia brevis |
Temperature Optimum [°C]
| Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
|---|---|---|---|
| 30 | - |
assay at | Karenia brevis |
pH Optimum
| pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
|---|---|---|---|
| 7 | - |
assay at | Karenia brevis |
IC50 Value
| IC50 Value | IC50 Value Maximum | Comment | Organism | Inhibitor | Structure |
|---|---|---|---|---|---|
| 3.05 | - |
pH 7.0, 30°C | Karenia brevis | cis-beta-methylstyrene oxide | |
| 6.99 | - |
pH 7.0, 30°C | Karenia brevis | beta-dimethylstyrene oxide | |
| 14.28 | - |
pH 7.0, 30°C | Karenia brevis | trans-beta-methylstyrene oxide | |
General Information
| General Information | Comment | Organism |
|---|---|---|
| evolution | epoxide hydrolases of the alpha,beta-hydrolase type share significant homologies with other hydrolases, including esterases. The two Karenia brevis EHs are similar in that each has two active site Tyrs as well as a Glu located after beta7. Both of the alpha,beta fold type EHs identified in Karenia brevis belong to the mEH class. The lengths of the NC loops of the EHs are 36 and 43 residues, whereas both cap-loops are 14 residues. mEHs are characterized by having long to very long NC-loops (33 or more residues) and short to medium cap-loops. The Karenia brevis NC-loops and cap-loops are considered very long and medium in length, respectively. The length of these domains is believed to govern substrate selectivity of the EH and this combination of long/med NC-loop/cap-loop would suggest selectivity for aromatic epoxides. The EH1 appears to deviate from this generalization as selectivity is observed for aliphatic over aromatic substituted epoxides | Karenia brevis |
| additional information | two step mechanism of the alpha,beta-hydrolase fold type and endo-tet and exo-tet cyclization mechanisms | Karenia brevis |
| physiological function | epoxide hydrolases are the key enzymes in the biosynthesis of polyether ladder compounds such as the brevetoxins which are produced by the dinoflagellate Karenia brevis, which is the principal HAB organism in the Gulf of Mexico also known as the Florida red tide dinoflagellate. Microsomal epoxide hydrolases, mEHs, are involved in the metabolism of xenobiotics | Karenia brevis |
Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.
Release 2023.1 (January 2023)
Legal
Curated at
Member of
