Evidence for Divergent Evolution of Growth Temperature Preference in Sympatric Saccharomyces Species

The genus Saccharomyces currently includes eight species in addition to the model yeast Saccharomyces cerevisiae, most of which can be consistently isolated from tree bark and soil. We recently found sympatric pairs of Saccharomyces species, composed of one cryotolerant and one thermotolerant species in oak bark samples of various geographic origins. In order to contribute to explain the occurrence in sympatry of Saccharomyces species, we screened Saccharomyces genomic data for protein divergence that might be correlated to distinct growth temperature preferences of the species, using the dN/dS ratio as a measure of protein evolution rates and pair-wise species comparisons. In addition to proteins previously implicated in growth at suboptimal temperatures, we found that glycolytic enzymes were among the proteins exhibiting higher than expected divergence when one cryotolerant and one thermotolerant species are compared. By measuring glycolytic fluxes and glycolytic enzymatic activities in different species and at different temperatures, we subsequently show that the unusual divergence of glycolytic genes may be related to divergent evolution of the glycolytic pathway aligning its performance to the growth temperature profiles of the different species. In general, our results support the view that growth temperature preference is a trait that may have undergone divergent selection in the course of ecological speciation in Saccharomyces

Candida glabrata : a review of its features and resistance

Candida species belong to the normal microbiota of the oral cavity and gastrointestinal and vaginal tracts, and are responsible for several clinical manifestations, from mucocutaneous overgrowth to bloodstream infections. Once believed to be non-pathogenic, Candida glabrata was rapidly blamable for many human diseases. Year after year, these pathological circumstances are more recurrent and problematic to treat, especially when patients reveal any level of immunosuppression. These difficulties arise from the capacity of C. glabrata to form biofilms and also from its high resistance to traditional antifungal therapies. Thus, this review intends to present an excerpt of the biology, epidemiology, and pathology of C. glabrata, and detail an approach to its resistance mechanisms based on studies carried out up to the present.The authors are grateful to strategic project PTDC/SAU-MIC/119069/2010 for the financial support to the research center and for Celia F. Rodrigues' grant

Tempo and Mode in Evolution of Transcriptional Regulation

Perennial questions of evolutionary biology can be applied to gene regulatory systems using the abundance of experimental data addressing gene regulation in a comparative context. What is the tempo (frequency, rate) and mode (way, mechanism) of transcriptional regulatory evolution? Here we synthesize the results of 230 experiments performed on insects and nematodes in which regulatory DNA from one species was used to drive gene expression in another species. General principles of regulatory evolution emerge. Gene regulatory evolution is widespread and accumulates with genetic divergence in both insects and nematodes. Divergence in cis is more common than divergence in trans. Coevolution between cis and trans shows a particular increase over greater evolutionary timespans, especially in sex-specific gene regulation. Despite these generalities, the evolution of gene regulation is gene- and taxon-specific. The congruence of these conclusions with evidence from other types of experiments suggests that general principles are discoverable, and a unified view of the tempo and mode of regulatory evolution may be achievable

Prévention de la résistance aux antibiotiques : une démarche « Une seule santé »

Ce document présente les principaux résultats de surveillance de la consommation d'antibiotiques et de la résistance des bactéries aux antibiotiques pour l'année 2021 en santé humaine, animale et dans l'environnement en priorisant des indicateurs communs, ainsi que des actions mises en oeuvre pour la prévention, le contrôle des infections et le bon usage des antibiotiques. Il cible les professionnels de santé humaine, animale et de l'environnement et est accessible à des professionnels non spécialistes de l'antibiorésistance. L'année 2021, encore marquée par l'épidémie de COVID-19, révèle un maintien global des progrès en termes de consommation d'antibiotiques et de résistance aux antibiotiques par rapport à 2019 mais aussi des points de vigilance concernant les prescriptions d'antibiotiques, notamment chez les plus jeunes en santé humaine ainsi que la résistance aux antibiotiques tant en santé humaine qu'en santé animale. Dans le domaine de l'environnement, les travaux se poursuivent pour identifier les indicateurs les plus pertinents et standardiser les méthodes de recueil et d'analyse de la présence d'antibiotiques et de marqueurs de résistance dans les milieux. Concernant la prévention de l'antibiorésistance, le document décrit le panel d'outils à la disposition des professionnels en santé humaine pour la prévention des infections et le bon usage des antibiotiques

Prévention de la résistance aux antibiotiques : une démarche « Une seule santé »

Ce document présente les principaux résultats de surveillance de la consommation d'antibiotiques et de la résistance des bactéries aux antibiotiques pour l'année 2022 en santé humaine, animale et dans l'environnement en priorisant des indicateurs communs, ainsi que des actions mises en œuvre pour la prévention, le contrôle des infections et le bon usage des antibiotiques. Il cible les professionnels de santé humaine, animale et de l'environnement et est accessible à des professionnels non spécialistes de l'antibiorésistance