Dissecting the bacterial type VI secretion system by a genome wide in silico analysis: what can be learned from available microbial genomic resources?

<p>Abstract</p> <p>Background</p> <p>The availability of hundreds of bacterial genomes allowed a comparative genomic study of the Type VI Secretion System (T6SS), recently discovered as being involved in pathogenesis. By combining comparative and phylogenetic approaches using more than 500 prokaryotic genomes, we characterized the global T6SS genetic structure in terms of conservation, evolution and genomic organization.</p> <p>Results</p> <p>This genome wide analysis allowed the identification of a set of 13 proteins constituting the T6SS protein core and a set of conserved accessory proteins. 176 T6SS loci (encompassing 92 different bacteria) were identified and their comparison revealed that T6SS-encoded genes have a specific conserved genetic organization. Phylogenetic reconstruction based on the core genes showed that lateral transfer of the T6SS is probably its major way of dissemination among pathogenic and non-pathogenic bacteria. Furthermore, the sequence analysis of the VgrG proteins, proposed to be exported in a T6SS-dependent way, confirmed that some C-terminal regions possess domains showing similarities with adhesins or proteins with enzymatic functions.</p> <p>Conclusion</p> <p>The core of T6SS is composed of 13 proteins, conserved in both pathogenic and non-pathogenic bacteria. Subclasses of T6SS differ in regulatory and accessory protein content suggesting that T6SS has evolved to adapt to various microenvironments and specialized functions. Based on these results, new functional hypotheses concerning the assembly and function of T6SS proteins are proposed.</p

En quête d'éthique ::dispositions légales et enjeux empiriques pour l'anthropologie

Ce document est la traduction de l’article « Searching for Ethics: Legal requirements and empirical issues for anthropology » (voir Perrin et al. 2018). Il analyse les nouvelles dispositions légales qui impactent les pratiques de recherche qualitative et contribuent à l’institutionnalisation de l’éthique de la recherche en Suisse. Après avoir contextualisé l’émergence de nouvelles formes de régulation de la recherche, il montre comment leurs présupposés épistémologiques affectent l’anthropologie. Il explore ensuite les enjeux liés à l’articulation entre éthique procédurale et éthique processuelle. Enfin, il examine les différentes postures qui pourraient être adoptées par les anthropologues et en sociales qualitatives

Searching for ethics ::legal requirements and empirical issues for anthropology

This paper analyses the new legal provisions impacting qualitative research practices and contributing to the institutionalization of research ethics in Switzerland. After contextualizing the emergence of new forms of research regulation, it shows how their epistemological assumptions challenge anthropology. It then explores the issues related to the articulation between procedural ethics and processual ethics. Finally, it discusses the different postures which might possibly be adopted by scholars in anthropology and other qualitative social sciences