Characterization of an epoxide hydrolase from the Florida red tide dinoflagellate, Karenia brevis.
Phytochemistry
; 122: 11-21, 2016 Feb.
Article
en En
| MEDLINE
| ID: mdl-26626160
ABSTRACT
Epoxide hydrolases (EH, EC 3.3.2.3) have been proposed to be key enzymes in the biosynthesis of polyether (PE) ladder compounds such as the brevetoxins which are produced by the dinoflagellate Karenia brevis. These enzymes have the potential to catalyze kinetically disfavored endo-tet cyclization reactions. Data mining of K. brevis transcriptome libraries revealed two classes of epoxide hydrolases microsomal and leukotriene A4 (LTA4) hydrolases. A microsomal EH was cloned and expressed for characterization. The enzyme is a monomeric protein with molecular weight 44kDa. Kinetic parameters were evaluated using a variety of epoxide substrates to assess substrate selectivity and enantioselectivity, as well as its potential to catalyze the critical endo-tet cyclization of epoxy alcohols. Monitoring of EH activity in high and low toxin producing cultures of K. brevis over a three week period showed consistently higher activity in the high toxin producing culture implicating the involvement of one or more EH in brevetoxin biosynthesis.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Dinoflagelados
/
Oxocinas
/
Epóxido Hidrolasas
/
Toxinas Marinas
País/Región como asunto:
America do norte
Idioma:
En
Revista:
Phytochemistry
Año:
2016
Tipo del documento:
Article