Université de Fribourg

Modulation of mgrB gene expression as a source of colistin resistance in Klebsiella oxytoca

Jayol, Aurélie ; Poirel, Laurent ; Villegas, Maria-Virginia ; Nordmann, Patrice

In: International Journal of Antimicrobial Agents, 2015, vol. 46, no. 1, p. 108–110

Gene modifications in the PmrAB and PhoPQ two-component regulatory systems, as well as inactivation of the mgrB gene, are known to be causes of colistin resistance in Klebsiella pneumoniae. The objective of this study was to characterise the mechanism involved in colistin resistance in a Klebsiella oxytoca isolate. A K. oxytoca clinical isolate showing resistance to colistin was recovered in...

Université de Fribourg

The cuticle and plant defense to pathogens

Metraux, Jean-Pierre ; Serrano, Mario ; Torres, Martha ; Coluccia, Fania ; L’Haridon, Floriane

In: Frontiers in Plant Science, 2014, vol. 5, p. 274

The cuticle provides a physical barrier against water loss and protects against irradiation, xenobiotics and pathogens. Components of the cuticle are perceived by invading fungi and activate developmental processes during pathogenesis. In addition, cuticle alterations of various types induce a syndrome of reactions that often results in resistance to necrotrophs. This article reviews the current...

Université de Fribourg

Production of reactive oxygen species and wound-induced resistance in Arabidopsis thaliana against Botrytis cinerea are preceded and depend on a burst of calcium

Beneloujaephajri, Emna ; Costa, Alex ; L’Haridon, Floriane ; Métraux, Jean-Pierre ; Binda, Matteo

In: BMC Plant Biology, 2013, vol. 13, no. 1, p. 160

Background: Wounded leaves of Arabidopsis thaliana produce reactive oxygen species (ROS) within minutes after wounding and become resistant to the pathogenic fungus Botrytis cinerea at a local level. This fast response of the plants to the wound is called wound-induced resistance (WIR). However the molecular mechanisms of this response and the signal cascade between the wound and ROS production...

Université de Fribourg

The impact of infection on host competition and its relationship to parasite persistence in a Daphnia microparasite system

Refardt, Dominik ; Ebert, Dieter

In: Evolutionary Ecology, 2012, vol. 26, no. 1, p. 95-107

Evolutionary studies often estimate fitness components with the aim to make predictions about the outcome of selection. Depending on the system and the question, different fitness components are used, but their usefulness for predicting the outcome of selection is rarely tested. Here we estimate host fitness components in different ways with the aim to test how well they agree with each other...

Université de Fribourg

Functional significance of triazine-herbicide resistance in defence of Senecio vulgaris against a rust fungus

Salzmann, Daniel ; Handley, Richard J. ; Müller-Schärer, Heinz

In: Basic and Applied Ecology, 2008, vol. 9, no. 5, p. 577-587

We investigated the functional significance of plant performance (dry mass, photosynthesis) in plant defence (resistance and tolerance) against pathogen infection, and potential negative cross-resistance between herbicide resistance and plant defence against disease. We compared isonuclear triazine-herbicide-resistant (TR) and -susceptible (TS) biotypes of Senecio vulgaris, in the presence and...