Binding of diarrheic shellfish poisoning toxins to okadaic acid binding proteins purified from the sponge Halichondria okadai.
Bioorg Med Chem
; 18(21): 7607-10, 2010 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-20863709
ABSTRACT
Okadaic acid (OA) and dinophysistoxin-1 (DTX1) cause diarrheic shellfish poisoning. This article examines the biochemical interactions of the two toxins with novel okadaic acid binding proteins (OABPs) 2.1 and 2.3, originally isolated from the marine sponge Halichondria okadai. First, recombinant OABPs 2.1 and 2.3 were expressed in Escherichia coli BL21 (DE3) cells. Binding assays using [24-(3)H]OA and the recombinant OABP 2.1 or 2.3 demonstrated the dissociation constant K(d) of 1.30±0.56 nM and 1.54±0.35 nM, respectively. Binding of [24-(3)H]okadaic acid to recombinant OABP2.1 was almost equally replaced with OA and DTX1. OA-induced cytotoxicity in mouse leukemia P388 cells was inhibited in the presence of the recombinant OABPs 2.1 and 2.3 with an EC(50) of 92±8.4 nM and 87±13 nM, respectively. These results suggest that the blockage of OA-induced cytotoxicity by OABPs 2.1 and 2.3 may be involved in regulating symbiotic relationships present in the sponge H. okadai.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Transporte
/
Ácido Okadáico
/
Toxinas Marinhas
Limite:
Animals
Idioma:
En
Revista:
Bioorg Med Chem
Assunto da revista:
BIOQUIMICA
/
QUIMICA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Japão