| Autor: |
Schesser, Kurt, Dukuzumuremyi, Jean-Marie, Cilio, Corrado, Borg, Stefan, Wallis, Tim S, Pettersson, Sven, Galyov, Edouard E |
| Zdroj: |
Microbial Pathogenesis; February 2000, Vol. 28 Issue: 2 p59-70, 12p |
| Abstrakt: |
The YopJ protein of Yersinia pseudotuberculosisinhibits several eukaryotic signalling pathways that are normally activated in cells following their contact with bacteria. Salmonellaencodes a protein, AvrA, that is secreted by the typeIII inv/spasecretion system which is clearly homologous to YopJ (56% identical, 87% similarity). Since AvrA and YopJs similarity also encompassed a region of YopJ that had previously been shown to be critical for its biological activity, we were interested whether AvrA and YopJ provoked similar responses in eukaryotic cells. Two different approaches were used to determine whether AvrA possesses YopJ-like activity in modulating cytokine expression or killing macrophages. An avrAstrain of Salmonella dublinwas constructed and its activity was compared to an isogenic wildtype counterpart in cellular response assays. In a complementary approach, AvrA was expressed in and delivered into eukaryotic cells by a yopJstrain of Yersinia pseudotuberculosis. We show here that AvrA affects neither cytokine expression or plays a role in macrophage killing when expressed by either Salmonellaor Yersinia. Additionally, AvrA does not possess SopB/D-like activity in promoting fluid secretion into infected calf ileal loops. These data indicate thatSalmonellaand Yersiniatrigger and/or modulate eukaryotic cell responses by different typeIII-secreted proteins and suggests that despite their close evolutionary relatedness, AvrA and YopJ perform different functions forSalmonellaand Yersinia, respectively. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
Full Text from ScienceDirect