Gæsteforsker - Roles of yeast regulatory pathways - 03.05.2012

Gæsteforsker Tiago Viana (ph.d.-studerende fra Instituto Superior de Agronoma, Technical University of Lisbon, Portugal) vil være på Fødevaremikrobiologi i perioden fra den 1. maj 2012 til den 31. oktober 2012. Han skal arbejde med følgende: 

 

"Preliminary Title of the Working Program

In search for roles of yeast regulatory pathways during the late stages of fermentation.

Background Information

During wine fermentation, yeast cells grow for a short period, reaching soon the stationary phase (as resting cells). As such, they accomplish most of the fermentation. Preliminary studies in the host laboratory suggest that at late stages yeast cells behave very differently from the well-recognized behavior of Saccharomyces cerevisiae. The aim of this work is to investigate how some regulatory pathways and some physiological mechanisms intervene in this behavior conferring high stress resistance and the ability to ferment hexoses up to exhaustion. To accomplish this goal, an integrated analysis of yeast functional genomics and yeast physiology is being performed. A contribution for better wine and for reduced sluggish and stuck fermentation problems is expected.

Task in Faculty of Life Sciences

In order to assess the implication of proton homeostasis on the physiological features of the cells at stationary phase:

- Intracellular (cytosolic and vacuolar) pH of single cells will be determined using Fluorescence Ratio Imaging Microscopy (Mortensen et al., 2008). This approach will reveal putative subpopulations of cells, which cannot be detected using the radio labeled propionic acid method.

Apoptotic and necrotic features will also be evaluated by fluorescent light microscopy with the appropriate filters under standard settings:

- Membrane integrity using direct PI staining."

 

Vejleder: Nils Arneborg