Bacillus pasteurii urease shares with plant ureases the ability to induce aggregation of blood platelets.
Arch Biochem Biophys
; 452(2): 149-55, 2006 Aug 15.
Article
en En
| MEDLINE
| ID: mdl-16839515
Ureases (EC 3.5.1.5) are highly homologous enzymes found in plants, bacteria and fungi. Canatoxin, an isoform Canavalia ensiformis urease, has several biological properties unrelated to its ureolytic activity, like platelet-aggregating and pro-inflammatory effects. Here, we describe that Bacillus pasteurii urease (BPU) also induces aggregation of rabbit platelets, similar to the canatoxin-induced effect (ED(50) 0.4 and 0.015 mg/mL, respectively). BPU induced-aggregation was blocked in platelets pretreated with dexamethasone and esculetin, a phospholipase A(2) and a lipoxygenase inhibitor, respectively, while platelets treated with indomethacin, a cyclooxygenase inhibitor, showed increased response to BPU. Methoxyverapamil (Ca(2+) channel blocker) and AMP (ADP antagonist) abrogated urease-induced aggregation, whereas the PAF-acether antagonist Web2170 had no effect. We concluded that platelet aggregation induced by BPU is mediated by lipoxygenase-derived eicosanoids and secretion of ADP from the platelets through a calcium-dependent mechanism. Potential relevance of these findings for bacterium-plant interactions and pathogenesis of bacterial infections are discussed.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de Plantas
/
Bacillus
/
Ureasa
/
Plaquetas
/
Agregación Plaquetaria
/
Fabaceae
Límite:
Animals
Idioma:
En
Revista:
Arch Biochem Biophys
Año:
2006
Tipo del documento:
Article
País de afiliación:
Brasil
Pais de publicación:
Estados Unidos