GTP-binding proteins are involved in the modulated activity of human neutrophils treated with the Panton-Valentine leukocidin from Staphylococcus aureus.
Infect Immun
; 62(12): 5281-9, 1994 Dec.
Article
en En
| MEDLINE
| ID: mdl-7960106
Significant amounts of leukotriene B4 (LTB4) are generated by human polymorphonuclear neutrophils (PMNs) after incubation with the Panton-Valentine leukocidin (Luk-PV) from Staphylococcus aureus V8 strains. We showed that GTP-binding proteins (G proteins) are involved in the Luk-PV-activated signal transduction of PMNs. ADP-ribosylation of heterotrimeric G proteins by cholera and pertussis toxins decreased the Luk-PV-induced LTB4-generation. In contrast, ADP-ribosylation of the low-molecular-weight G proteins rho and rac by Clostridium botulinum exoenzyme C3 increased the Luk-PV-induced LTB4 synthesis. The subsequent stimulation of Luk-PV-treated PMNs by either calcium ionophore A23187, sodium fluoride, or formylmethionyl-leucyl-phenylalanine was significantly inhibited. This decrease was paralleled by a loss of G-protein functions, including GTPase activity and GTP-binding capacity. An increase of G-protein functions was obtained with low amounts of Luk-PV. In addition to the modulated G-protein functions, ADP-ribosylation of 24-, 40-, and 45-kDa proteins by Luk-PV was detected. As shown in control experiments, the ADP-ribosylated 24-kDa proteins were not substrates for C. botulinum exoenzyme C3. Introduction of ras p21 into digitonin-permeabilized PMNs was without effect on subsequent Luk-PV stimulation. In addition, the translocation of ras p21, ras GAP, and 5-lipoxygenase into the membrane of Luk-PV-treated PMNs, as well as the expression of chemotactic membrane receptors for LTB4 and formylmethionyl leucyl phenylalanine, was significantly diminished.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Staphylococcus aureus
/
Leucotrieno B4
/
Proteínas de Unión al GTP
/
Leucocidinas
/
Neutrófilos
Límite:
Humans
Idioma:
En
Revista:
Infect Immun
Año:
1994
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Estados Unidos