INVESTIGADORES
COMERCI Diego Jose
artículos
Título:
Phosphatidylethanolamine synthesis is required for optimal virulence of Brucella abortus
Autor/es:
BUKATA, L.; SILVIA ALTABE; DIEGO DE MENDOZA; UGALDE, R. A.; DIEGO JOSE COMERCI
Revista:
JOURNAL OF BACTERIOLOGY
Editorial:
ASM Press
Referencias:
Año: 2008 vol. 190 p. 8197 - 8203
ISSN:
0021-9193
Resumen:
The Brucella cell envelope contains the zwitterionic phospholipids phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Synthesis of PC occurs exclusively via the phosphatidylcholine synthase pathway, implying that the pathogen depends on the choline synthesized by the host cell to form PC. Notably, PC is necessary to sustain a chronic infection process, which suggests that the membrane lipid content is relevant for Brucella virulence. In this study we investigated the first step of PE biosynthesis in B. abortus which is catalyzed by phosphatidylserine synthase (PssA). Disruption of pssA abrogated the synthesis of PE without affecting the growth in rich complex medium. In minimal medium however, the mutant required choline supplementation for growth, suggesting that at least PE or PC are necessary for Brucella viability. Absence of PE altered cell surface properties but most importantly, it impaired several virulence traits of B. abortus such as intracellular survival in both macrophages and HeLa cells, the maturation of the replicative Brucella-containing vacuole and mice colonization. These results suggest that membrane phospholipid composition is critical for the interaction of B. abortus with the host cell