Site-directed mutagenesis of human prostacyclin synthase: Alteration of Cys441 of the Cys-pocket, and Glu347 and Arg350 of the EXXR motif.
FEBS Lett
; 389(3): 268-72, 1996 Jul 08.
Article
en En
| MEDLINE
| ID: mdl-8766713
ABSTRACT
The possible active site Cys441 in the Cys-pocket and Glu347 and Arg350 of the EXXR motif of the human prostacyclin synthase, which catalyzes the conversion of prostaglandin H2 to prostacyclin, were subjected to site-directed mutagenesis in order to understand the role of these residues in expressing the enzymatic activity. Five expression vectors encoding the mutant enzymes with a single replacement, Cys441 Ala, Cys441 Ser, Cys441 His, Glu347 Ala and Arg350 Ala, as well as the wild-type enzyme were expressed in 293 cells. The microsomal fraction of the cells expressing the wild-type enzyme showed a specific activity of 96 nmol 6-keto-PGF1alpha/min per mg protein. All of the mutant enzymes examined showed no detectable enzyme activity, although immunoblot analysis demonstrated that levels of all the expressed mutant enzymes were similar to that of the wild-type enzyme. These results indicated that the Cys441 in the Cys-pocket, and Glu347 and Arg350 of the EXXR motif of human prostacyclin synthase are important for expressing the enzymatic activity.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Mutagénesis Sitio-Dirigida
/
Oxidorreductasas Intramoleculares
/
Sistema Enzimático del Citocromo P-450
/
Isomerasas
Límite:
Humans
Idioma:
En
Revista:
FEBS Lett
Año:
1996
Tipo del documento:
Article
País de afiliación:
Japón