Enzymatic actions of Pasteurella multocida toxin detected by monoclonal antibodies recognizing the deamidated α subunit of the heterotrimeric GTPase Gq.
FEBS J
; 278(15): 2702-12, 2011 Aug.
Article
em En
| MEDLINE
| ID: mdl-21624053
ABSTRACT
Pasteurella multocida toxin (PMT) is a virulence factor responsible for the pathogenesis of some Pasteurellosis. PMT exerts its toxic effects through the activation of heterotrimeric GTPase (G(q), G(12/13) and G(i))-dependent pathways, by deamidating a glutamine residue in the α subunit of these GTPases. However, the enzymatic characteristics of PMT are yet to be analyzed in detail because the deamidation has only been observed in cell-based assays. In the present study, we developed rat monoclonal antibodies, specifically recognizing the deamidated Gα(q), to detect the actions of PMT by immunological techniques such as western blotting. Using the monoclonal antibodies, we found that the toxin deamidated Gα(q) only under reducing conditions. The C-terminal region of PMT, C-PMT, was more active than the full-length PMT. The C3 domain possessing the enzyme core catalyzed the deamidation in vitro without any other domains. These results not only support previous observations on toxicity, but also provide insights into the enzymatic nature of PMT. In addition, we present several lines of evidence that Gα(11), as well as Gα(q), could be a substrate for PMT.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Toxinas Bacterianas
/
Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP
Limite:
Animals
Idioma:
En
Revista:
FEBS J
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Japão