Stress Responses in Wine Yeast

ABSTRACT Commercial wine yeast strains of the species Saccharomyces cerevisiae have been selected to satisfy many different, and sometimes highly specific, oenological requirements. As a consequence, more than 200 different strains with significantly diverging phenotypic traits are produced globally. This genetic resource has been rather neglected by the scientific community because industrial strains are less easily manipulated than the limited number of laboratory strains that have been successfully employed to investigate fundamental aspects of cellular biology. However, laboratory strains are unsuitable for the study of many phenotypes that are of significant scientific and industrial interest. Here, we investigate whether a comparative transcriptomics and phenomics approach, based on the analysis of five phenotypically diverging industrial wine yeast strains, can provide insights into the molecular networks that are responsible for the expression of such phenotypes. For this purpose, some oenologically relevant phenotypes, including resistance to various stresses, cell wall properties, and metabolite production of these strains were evaluated and aligned with transcriptomic data collected during alcoholic fermentation. The data reveal significant differences in gene regulation between the five strains. While the genetic complexity underlying the various successive stress responses in a dynamic system such as wine fermentation reveals the limits of the approach, many of the relevant differences in gene expression can be linked to specific phenotypic differences between the strains. This is, in particular, the case for many aspects of metabolic regulation. The comparative approach therefore opens new possibilities to investigate complex phenotypic traits on a molecular level.

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Effect of salt hyperosmotic stress on yeast cell viability

Zbornik Matice srpske za prirodne nauke ◽

10.2298/zmspn0713271l ◽

2007 ◽

pp. 271-284 ◽

Cited By ~ 9

Author(s):

Stelios Logothetis ◽

Graeme Walker ◽

Elias Nerantzis

Keyword(s):

Cell Viability ◽

Yeast Cell ◽

Stress Responses ◽

Transcriptional Activation ◽

Yeast Strain ◽

Research Work ◽

Wine Yeast ◽

Yeast Cells ◽

Wine Yeast Strain ◽

The Impact

During fermentation for ethanol production, yeasts are subjected to different kinds of physico-chemical stresses such as: initially high sugar concentration and low temperature; and later, increased ethanol concentrations. Such conditions trigger a series of biological responses in an effort to maintain cell cycle progress and yeast cell viability. Regarding osmostress, many studies have been focused on transcriptional activation and gene expression in laboratory strains of Saccharomyces cerevisiae. The overall aim of this present work was to further our understanding of wine yeast performance during fermentations under osmotic stress conditions. Specifically, the research work focused on the evaluation of NaCl-induced stress responses of an industrial wine yeast strain S. cerevisiae (VIN 13), particularly with regard to yeast cell growth and viability. The hypothesis was that osmostress conditions energized specific genes to enable yeast cells to survive under stressful conditions. Experiments were designed by pretreating cells with different sodium chloride concentrations (NaCl: 4%, 6% and 10% w/v) growing in defined media containing D-glucose and evaluating the impact of this on yeast growth and viability. Subsequent fermentation cycles took place with increasing concentrations of D-glucose (20%, 30%, 40% w/v) using salt-adapted cells as inocula. We present evidence that osmostress induced by mild salt pre-treatments resulted in beneficial influences on both cell viability and fermentation performance of an industrial wine yeast strain.

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Monitoring Stress-Related Genes during the Process of Biomass Propagation of Saccharomyces cerevisiae Strains Used for Wine Making

Applied and Environmental Microbiology ◽

10.1128/aem.71.11.6831-6837.2005 ◽

2005 ◽

Vol 71 (11) ◽

pp. 6831-6837 ◽

Cited By ~ 40

Author(s):

Roberto Pérez-Torrado ◽

Jose M. Bruno-Bárcena ◽

Emilia Matallana

Keyword(s):

Saccharomyces Cerevisiae ◽

Stress Response ◽

Biomass Production ◽

Stress Responses ◽

Environmental Changes ◽

Wine Yeast ◽

Yeast Cells ◽

Mrna Levels ◽

Yeast Biomass ◽

Stress Related Genes

ABSTRACT Physiological capabilities and fermentation performance of Saccharomyces cerevisiae strains to be employed during industrial wine fermentations are critical for the quality of the final product. During the process of biomass propagation, yeast cells are dynamically exposed to a mixed and interrelated group of known stresses such as osmotic, oxidative, thermic, and/or starvation. These stressing conditions can dramatically affect the parameters of the fermentation process and the technological abilities of the yeast, e.g., the biomass yield and its fermentative capacity. Although a good knowledge exists of the behavior of S. cerevisiae under laboratory conditions, insufficient knowledge is available about yeast stress responses under the specific media and growth conditions during industrial processes. We performed growth experiments using bench-top fermentors and employed a molecular marker approach (changes in expression levels of five stress-related genes) to investigate how the cells respond to environmental changes during the process of yeast biomass production. The data show that in addition to the general stress response pathway, using the HSP12 gene as a marker, other specific stress response pathways were induced, as indicated by the changes detected in the mRNA levels of two stress-related genes, GPD1 and TRX2. These results suggest that the cells were affected by osmotic and oxidative stresses, demonstrating that these are the major causes of the stress response throughout the process of wine yeast biomass production.

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Emotions and health: The impact of emotions, emotions regulation, music, and acculturation on health

Zeitschrift für Gesundheitspsychologie ◽

10.1026/0943-8149.16.3.112 ◽

2008 ◽

Vol 16 (3) ◽

pp. 112-115 ◽

Cited By ~ 1

Author(s):

Stephan Bongard ◽

Volker Hodapp ◽

Sonja Rohrmann

Keyword(s):

Stress Responses ◽

Physiological Stress ◽

Anger Expression ◽

Domain Specific ◽

Cardiovascular Stress ◽

Expression Behavior ◽

Cardio Vascular ◽

And Coping ◽

Relationship Of ◽

The Impact

Abstract. Our unit investigates the relationship of emotional processes (experience, expression, and coping), their physiological correlates and possible health outcomes. We study domain specific anger expression behavior and associated cardio-vascular loads and found e.g. that particularly an open anger expression at work is associated with greater blood pressure. Furthermore, we demonstrated that women may be predisposed for the development of certain mental disorders because of their higher disgust sensitivity. We also pointed out that the suppression of negative emotions leads to increased physiological stress responses which results in a higher risk for cardiovascular diseases. We could show that relaxation as well as music activity like singing in a choir causes increases in the local immune parameter immunoglobuline A. Finally, we are investigating connections between migrants’ strategy of acculturation and health and found e.g. elevated cardiovascular stress responses in migrants when they where highly adapted to the German culture.

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Childbirth and Posttraumatic Stress Responses

European Journal of Psychological Assessment ◽

10.1027/1015-5759.22.4.259 ◽

2006 ◽

Vol 22 (4) ◽

pp. 259-267 ◽

Cited By ~ 40

Author(s):

Eelco Olde ◽

Rolf J. Kleber ◽

Onno van der Hart ◽

Victor J.M. Pop

Keyword(s):

Posttraumatic Stress Disorder ◽

Posttraumatic Stress ◽

Stress Responses ◽

Rating Scales ◽

Rating Scale ◽

Stress Disorder ◽

Traumatic Experience ◽

Event Scale ◽

Self Rating ◽

The Impact

Childbirth has been identified as a possible traumatic experience, leading to traumatic stress responses and even to the development of posttraumatic stress disorder (PTSD). The current study investigated the psychometric properties of the Dutch version of the Impact of Event Scale-Revised (IES-R) in a group of women who recently gave birth (N = 435). In addition, a comparison was made between the original IES and the IES-R. The scale showed high internal consistency (α = 0.88). Using confirmatory factor analysis no support was found for a three-factor structure of an intrusion, an avoidance, and a hyperarousal factor. Goodness of fit was only reasonable, even after fitting one intrusion item on the hyperarousal scale. The IES-R correlated significantly with scores on depression and anxiety self-rating scales, as well as with scores on a self-rating scale of posttraumatic stress disorder. Although the IES-R can be used for studying posttraumatic stress reactions in women who recently gave birth, the original IES proved to be a better instrument compared to the IES-R. It is concluded that adding the hyperarousal scale to the IES-R did not make the scale stronger.

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