Retargeting of heterologous enzymes results in improved β-carotene synthesis in Saccharomyces cerevisiae.

Aims: Carotenoids are a class of hydrophobic substances that are important as food and feed colorants and as antioxidants. The pathway for β-carotene synthesis has been expressed in various yeast species, albeit with rather low yields and titers. The inefficient conversion of phytoene to lycopene is often regarded as a bottleneck in the pathway.

Engineering of Saccharomyces cerevisiae for the accumulation of high amounts of triacylglycerol.

Background: Fatty acid-based substances play an important role in many products, from food supplements to pharmaceutical products and biofuels. The production of fatty acids, mainly in their esterified form as triacylglycerol (TAG), has been intensively studied in oleaginous yeasts, whereas much less effort has been invested into non-oleaginous species. In the present work, we engineered the model yeast Saccharomyces cerevisiae, which is commonly regarded as non-oleaginous, for the storage of high amounts of TAG, comparable to the contents achieved in oleaginous yeasts.

Characterization of a lipid droplet protein from Yarrowia lipolytica that is required for its oleaginous phenotype.

Oleaginous microorganisms are characterized by their ability to store high amounts of triacylglycerol (TAG) in intracellular lipid droplets (LDs). In this work, we characterized a protein of the oleaginous yeast Yarrowia lipolytica that is associated with LD and plays a role in the regulation of TAG storage. This protein is required for the oleaginous phenotype of Y.

Quantitative modeling of triacylglycerol homeostasis in yeast--metabolic requirement for lipolysis to promote membrane lipid synthesis and cellular growth.

Triacylglycerol metabolism in Saccharomyces cerevisiae was analyzed quantitatively using a systems biological approach. Cellular growth, glucose uptake and ethanol secretion were measured as a function of time and used as input for a dynamic flux-balance model. By combining dynamic mass balances for key metabolites with a detailed steady-state analysis, we trained a model network and simulated the time-dependent degradation of cellular triacylglycerol and its interaction with fatty acid and membrane lipid synthesis.