Flow cytometry and capillary electrophoresis analyses in ethanol-stressedOenococcus oenistrains and changes assessment of membrane fatty acid composition

Abstract

Intermediate physiological state assessment in O. oeni with recovery possibility could be an important criterion for potential starter culture application. The flow cytometry application with changes in monitoring membrane fatty acid composition and in surface charging rates allowed the characterization of sorted subpopulations that may contribute to further understanding of diversity and heterogeneity in physiology of bacterial populations.

Ethanol stress in Oenococcus oeni : transcriptional response and complex physiological mechanisms

“…In the study by Bonomo et al . (), the increase in saturation degree in all ethanol‐grown cells represented a protective increase in O. oeni against the toxic effect of ethanol, balancing the rise in membrane fluidity normally attributed to ethanol. Many authors studied, with contradictory results, the deleterious effect of ethanol on membrane modifications in micro‐organisms and also in different O. oeni strains (Teixeira et al .…”

“…The induction of cfa gene expression was demonstrated in O. oeni cells grown in the presence of ethanol or at low pH and the increased levels of cfa mRNA transcripts correlated with increased amounts of CFA in the membrane suggesting that the expression of this gene may be regulated at the transcriptional level (Grandvalet et al 2008). Moreover, a correlation between the physical state of the membrane and proton permeability has been also established; the presence of ethanol resulted in increased permeability of the membrane and leads to the dissipation of the PMF generated by both MLF and citrate metabolism (Bonomo et al 2017). In the study by Bonomo et al (2017), the increase in saturation degree in all ethanol-grown cells represented a protective increase in O. oeni against the toxic effect of ethanol, balancing the rise in membrane fluidity normally attributed to ethanol.…”

“…Moreover, a correlation between the physical state of the membrane and proton permeability has been also established; the presence of ethanol resulted in increased permeability of the membrane and leads to the dissipation of the PMF generated by both MLF and citrate metabolism (Bonomo et al . ).…”

“…Ethanol affects the physical-chemical state and biological functions of cell membranes. It interacts with membranes at the lipid-water interface, weakening the hydrophobic barrier to the free exchange of polar molecules, thereby perturbing membrane structure and function (Bonomo et al 2017).…”

“…Moreover, a correlation between the physical state of the membrane and proton permeability has been also established; the presence of ethanol resulted in increased permeability of the membrane and leads to the dissipation of the PMF generated by both MLF and citrate metabolism (Bonomo et al 2017). In the study by Bonomo et al (2017), the increase in saturation degree in all ethanol-grown cells represented a protective increase in O. oeni against the toxic effect of ethanol, balancing the rise in membrane fluidity normally attributed to ethanol. Many authors studied, with contradictory results, the deleterious effect of ethanol on membrane modifications in micro-organisms and also in different O. oeni strains (Teixeira et al 2002;da Silveira et al 2003;Grandvalet et al 2008;Guzzo et al 2011).…”