Effect of Adaptation to Ethanol on Cytoplasmic and Membrane Protein Profiles of Oenococcus oeni

Abstract

The practical application of commercial malolactic starter cultures of Oenococcus oeni surviving direct inoculation in wine requires insight into mechanisms of ethanol toxicity and of acquired ethanol tolerance in this organism. Therefore, the site-specific location of proteins involved in ethanol adaptation, including cytoplasmic, membrane-associated, and integral membrane proteins, was investigated. Ethanol triggers alterations in protein patterns of O. oeni cells stressed with 12% ethanol for 1 h and those of cells grown in the presence of 8% ethanol. Levels of inosine-5-monophosphate dehydrogenase and phosphogluconate dehydrogenase, which generate reduced nicotinamide nucleotides, were decreased during growth in the presence of ethanol, while glutathione reductase, which consumes NADPH, was induced, suggesting that maintenance of the redox balance plays an important role in ethanol adaptation. Phosphoenolpyruvate:mannose phosphotransferase system (PTS) components of mannose PTS, including the phosphocarrier protein HPr and EII Man , were lacking in ethanol-adapted cells, providing strong evidence that mannose PTS is absent in ethanoladapted cells, and this represents a metabolic advantage to O. oeni cells during malolactic fermentation. In cells grown in the presence of ethanol, a large increase in the number of membrane-associated proteins was observed. Interestingly, two of these proteins, dTDT-glucose-4,6-dehydratase and D-alanine:D-alanine ligase, are known to be involved in cell wall biosynthesis. Using a proteomic approach, we provide evidence for an active ethanol adaptation response of O. oeni at the cytoplasmic and membrane protein levels.

The cell-envelope proteome of Bifidobacterium longum in an in vitro bile environment

“…In relation to this, with the aim of determining the protein profile of the B. longum envelope, and as a first approach to undertaking deeper functional studies, we analysed different subcellular fractions. The application of gel-based and gel-free technologies, combined with high-throughput techniques, allowed us to identify 218 proteins; about 70 % of them were predicted to be, or were previously described as being, in the cell envelope of Gram-positive bacteria (Antikainen et al, 2007;Candela et al, 2007;Eymann et al, 2004;Granato et al, 2004;Jang & Hanash 2003;Kelly et al, 2005b;Nandakumar et al, 2005;Rivera-Amill et al, 2001;Rodríguez-Ortega et al, 2006;Schaumburg et al, 2004;Severin et al, 2007;Silveira et al, 2004;Tjalsma et al, 2008;Wolff et al, 2007). Furthermore, 48 of them are predicted to be integral membrane proteins (contain hypothetical transmembrane segments) and 30 of them have different extracytoplasmic sorting signals.…”

Effect of acclimation medium on cell viability, membrane integrity and ability to consume malic acid in synthetic wine by oenologicalLactobacillus plantarumstrains

“…Bacterial exposure to stress factors such as low pH, ethanol or low temperatures, induces membrane changes that are well documented in the literature. These membrane changes include the decrease in the membrane fluidity as a result of alterations in the fatty acid composition (Bastianini et al 2000;Chu-Ky et al 2005), or the induction of small heat shock proteins LO18 (Guzzo et al 1997), and accordingly modification of both cytoplasmic and membrane protein profiles (Silveira et al 2004).…”

Very Low Ethanol Concentrations Affect the Viability and Growth Recovery in Post-Stationary-Phase Staphylococcus aureus Populations

“…In a recent study with the gram-positive organism Bacillus subtilis, it was demonstrated that treatment with subinhibitory concentrations of ethanol (not affecting vegetative growth) inhibited the initiation of spore development through a selective blockage of key developmental genes under the control of the master transcription factor Spo0AϳP (14). These toxic effects have been described for a wide variety of microbial species, and for use of different concentrations of ethanol, ranging from 2.5% to 70% (1,2,8,10,19,25,36). Surprisingly, very little is known about the physiological effects of VLEC.…”

“…The bactericidal activity of ethanol is due to several factors: disruption of membrane structure or function (1,12,15,36); interference with cell division, affecting steady-state growth (12); variations in fatty acid composition and protein synthesis (8); inhibition of nutrient transport via membrane-bound ATPases (4); alteration of membrane ⌬pH (4, 40) and membrane potential (⌬) (40); and a decrease in intracellular pH (4,18,40). In a recent study with the gram-positive organism Bacillus subtilis, it was demonstrated that treatment with subinhibitory concentrations of ethanol (not affecting vegetative growth) inhibited the initiation of spore development through a selective blockage of key developmental genes under the control of the master transcription factor Spo0AϳP (14).…”