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Vernay, T.

Publications and source records attributed to Vernay, T..

2 recordsLinked to original sources

The Molecules Gateway: a homogeneous, searchable database of 150k annotated molecules from Actinomycetes

Natural products are a sustainable resource for drug discovery, but their identification in complex mixtures remains a daunting task. We present an automated pipeline that compares, harmonizes and ranks the annotations of LC-HRMS data by different tools. When applied to 7,400 extracts derived from 6,566 strains belonging to 86 actinomycete genera, it yielded 150,000 molecules after processing over 50 million MS features. The web-based Molecules Gateway provides a highly interactive access to experimental and calculated data for these molecules, along with the metadata related to extracts and producer strains. We show how the Molecules Gateway can be used to rapidly identify known hard to find microbial products, unreported analogs of known families and not yet described metabolites. The Molecules Gateway, which complements available repositories of annotated MS data, is experimentally and computationally homogeneous, and thus amenable to global analyses, which show a large and untapped chemical diversity afforded by actinomycetes.

microbiology↗

Chlamydia-driven ISG15 expression dampens the immune response of epithelial cells independently of ISGylation

Excessive inflammation upon C. trachomatis infection can cause severe damages in the female genital tract. This obligate intracellular bacterium develops mainly in epithelial cells, whose innate response contributes to the overall inflammatory response to infection. The ubiquitin-like protein interferon-stimulated gene 15 (ISG15) stimulates interferon {gamma} (IFN{gamma}) production and is required for bacterial clearance in several infectious contexts. Here, we describe and investigate the consequences of the increase in ISG15 expression by epithelial cells infected with C. trachomatis. Infection of HeLa cells and primary ecto-cervical epithelial cells resulted in a transcriptional up-regulation of ISG15 expression. This did not involve the canonical IFN-I signaling pathway and depended instead on the activation of the STING/TBK1/IRF3 pathway. Absence or reduction of ISG15 synthesis led to increased production of several cytokines and chemokines including interleukin (IL) 6 and IL8, implicating that ISG15 normally dampens the immune response induced by C. trachomatis infection in epithelial cells. ISG15 exerted its control from an intracellular location, but without involving ISGylation. Finally, higher levels of inflammation and delayed bacterial clearance were observed in the genital tracts of ISG15-KO mice infected by C. trachomatis compared to wild type animals, however IFN{gamma} production was unchanged. Altogether, our data show that ISG15 expression acts as a brake on the immune response to C. trachomatis infection in epithelial cells and limits bacterial burden and inflammation in mice.

microbiology↗