Effect of ethanol perturbation on viscosity and permeability of an inner membrane in Bacillus subtilis spores.
Fiche publication
Date publication
septembre 2016
Journal
Biochimica et biophysica acta
Auteurs
Membres identifiés du Cancéropôle Est :
Pr PERRIER-CORNET Jean-Marie
Tous les auteurs :
Loison P, Gervais P, Perrier-Cornet JM, Kuimova MK
Lien Pubmed
Résumé
In this work, we investigated how a combination of ethanol and high temperature (70°C), affect the properties of the inner membrane of Bacillus subtilis spores. We observed membrane permeabilization for ethanol concentrations ≥50%, as indicated by the staining of the spores' DNA by the cell impermeable dye Propidium Iodide. The loss of membrane integrity was also confirmed by a decrease in the peak corresponding to dipicolinic acid using infrared spectroscopy. Finally, the spore refractivity (as measured by phase contrast microscopy) was decreased after the ethanol-heat treatment, suggesting a partial rehydration of the protoplast. Previously we have used fluorescent lifetime imaging microscopy (FLIM) combined with the fluorescent molecular rotor Bodipy-C12 to study the microscopic viscosity in the inner membrane of B. subtilis spores, and showed that at normal conditions it is characterized by a very high viscosity. Here we demonstrate that the ethanol/high temperature treatment led to a decrease of the viscosity of the inner membrane, from 1000cP to 860cP for wild type spores at 50% of ethanol. Altogether, our present work confirms the deleterious effect of ethanol on the structure of B. subtilis spores, as well as demonstrates the ability of FLIM - Bodipy-C12 to measure changes in the microviscosity of the spores upon perturbation.
Mots clés
Bacillus subtilis, chemistry, Boron Compounds, chemistry, Cell Membrane, chemistry, Ethanol, chemistry, Microscopy, Fluorescence, Permeability, Spores, Bacterial, chemistry, Viscosity
Référence
Biochim. Biophys. Acta. 2016 09;1858(9):2060-2069