Transient responses of yeasts to glucose excess

Flocculation of brewers' yeast: Quantification, modelling and control

The Golgi: A transition point in membrane lipid composition and topology

The exciting developments in the fields of sphingolipid-mediated signal transduction and sphingolipid-mediated protein sorting have led to a tremendous activity in the studies of sphingolipid organization in biomembranes, especially the structural role of sphingolipids in membrane rafts. It is now being realized that rafts may exist in many...

Engineering of aromatic amino acid metabolism in Saccharomyces cerevisiae

Saccharomyces cerevisiae is a popular industrial microorganism. It has since long been used in bread, beer and wine making. More recently it is also being applied for heterologous protein production and as a target organism for metabolic engineering. The work presented in this thesis describes how S. cerevisiae may be used as a metabolic...

Engineering of Saccharomyces cerevisiae for the production of fuel ethanol from xylose

For various reasons mankind is looking for alternatives for fossil fuels. One of these alternatives is ethanol made from plant biomass. However, the plant material when broken down by hydrolysis into its sugar monomers contains a significant amount of xylose, a 5-carbon-sugar or pentose. Contrary to the sugars with 6 carbon atoms (hexoses) wild...

Physiological impact and context dependency of transcriptional responses: A chemostat study in Saccharomyces cerevisiae

This thesis is a compilation of a four-year PhD project on bakers' yeast (Saccharomyces cerevisiae). Since the entire S. cerevisiae genome sequence became available in 1996, DNA-microarray analysis has become a popular high-information-density tool for analyzing gene expression in this important industrial microorganism and model eukaryote. This...

Stimulus response methodology for quantitative model development of central carbon metabolism in Saccharomyces cerevisiae

Abstract not available

Functional genomics of beer-related physiological processes in yeast

Since the release of the entire genome sequence of the S. cerevisiae laboratory strain S288C in 1996, many functional genomics tools have been introduced in fundamental and application-oriented yeast research. In this thesis, the applicability of functional genomics for the improvement of yeast in beer-related processes is investigated. To this...

Metabolic engineering of Saccharomyces cerevisiae for C4-dicarboxylic acid production

Biotechnological production of chemicals from renewable feedstocks offers a sustainable alternative to petrochemistry. Understanding of the biology of microorganisms and plants is increasing at an unprecedented rate and tools with which these organisms can be engineered for industrial application are becoming ever more powerful. However,...

Metabolic engineering of free-energy (ATP) conserving reactions in Saccharomyces cerevisiae

Metabolic engineering – the improvement of cellular activities by manipulation of enzymatic, transport and regulatory functions of the cell – has enabled the industrial production of a wide variety of biological molecules from renewable resources. Microbial production of fuels and chemicals thereby provides an alternative to oil-based production...

Towards fermentation of galacturonic acid-containing feedstocks with Saccharomyces cerevisiae

The ambition to reduce our current dependence on fossil transportation fuels has driven renewed interest in bioethanol. Pectin-rich feedstocks like sugar beet pulp and citrus peel, which are currently sold as cattle feed, are promising raw materials for the production of bioethanol. This thesis explores the challenges related to the fermentation...

Reducing the genetic complexity of glycolysis in Saccharomyces cerevisiae

Glycolysis, a biochemical pathway that oxidizes glucose to pyruvate, is at the core of sugar metabolism in Saccharomyces cerevisiae (bakers’ yeast). Glycolysis is not only a catabolic route involved in energy conservation, but also provides building blocks for anabolism. From an applied perspective, several glycolytic intermediates are key...

Analysis of the hybrid genomes of brewing yeasts

One of the best guarded secrets of brewers is represented by the brewing yeast employed in beer fermentation, due to its profound impact upon the specific flavour profile of the final product. The current research tackles the genome diversity of lager brewing strains as well as their impact on important phenotypic traits. Furthermore, the...

Molecular responses of Saccharomyces cerevisiae to near-zero growth rates

Engineering of vitamin and cofactor synthesis in yeasts

The increase in world population together with an unsustainable and fossil fuel-based economy are at the root of the significant increase in the average global temperature since the pre-industrial era. Switching to a more sustainable and circular bio-based economy is one of the main pillars included in the Paris agreement aimed at reducing green...

Droplet microfluidics for bioprocess engineering

A crucial challenge during the initial stages of bioprocess development is that tools used to screen microorganisms and optimize cultivation conditions do not represent the environment imposed at industrial scale. Inside an industrial-scale bioreactor, microorganisms are often cultivated under fed-batch conditions, where nutrients are supplied...

Enabling yeast replication in extreme cold and heat

Open questions are whether life can be enabled in uninhabitable environments, and whether there is a limit to howmuch one can tune the speed of proliferation. Answering such questions has broad implications. It may reveal whether we can live in unforeseen habitats, whether we can slow down aging, and whether there are limits to lifespan. In this...

The path towards prediction: An exploration of the evolutionary dynamics of the yeast polarity network

All living systems possess the ability to evolve. This ability has allowed life to adopt a large diversity of shapes, colors, sizes and lifestyles. However, despite being a fundamental property of life, our knowledge of what makes living systems evolvable is limited. The fact that evolution can be sometimes be hopelessly unpredictable while in...