PhoQ is an unsaturated fatty acid receptor that fine-tunes Salmonella pathogenic traits.

PhoQ is an unsaturated fatty acid receptor that fine-tunes Salmonella pathogenic traits. Sci Signal. 2020 Apr 21;13(628): Authors: Carabajal MA, Viarengo G, Yim L, Martínez-Sanguiné A, Mariscotti JF, Chabalgoity JA, Rasia RM, Véscovi EG Abstract The Salmonella enterica PhoP/PhoQ two-component signaling system coordinates the spatiotemporal expression of key virulence factors that confer pathogenic traits. Through biochemical and structural analyses, we found that the sensor histidine kinase PhoQ acted as a receptor for long-chain unsaturated fatty acids (LCUFAs), which induced a conformational change in the periplasmic domain of the PhoQ protein. This resulted in the repression of PhoQ autokinase activity, leading to inhibition of the expression of PhoP/PhoQ-dependent genes. Recognition of the LCUFA linoleic acid (LA) by PhoQ was not stereospecific because positional and geometrical isomers of LA equally inhibited PhoQ autophosphorylation, which was conserved in multiple S. enterica serovars. Because orally acquired Salmonella encounters conjugated LA (CLA), a product of the metabolic conversion of LA by microbiota, in the human intestine, we tested how short-term oral administration of CLA affected gut colonization and systemic dissemination in a mouse model of Salmonella-induced colitis. Compared to untreated mice, CLA-treated mice showed increased gut colonization by wild-type Salmonella, as well as increased dissemination to t...
Source: Science Signaling - Category: Biomedical Science Authors: Tags: Sci Signal Source Type: research