Project

Regime shifts in production versus diversification

In this project we explore regime shifts and tipping points in land-use systems. These systems combine conventional food production with the provision of other ecosystem services. Our aim is to improve understanding how (multifunctional) land use - based on ecosystem services - can be maintained by self-governance in mixed public and private communities. We investigate how such multifunctional land use systems can be provoked by governmental incentives and how they are affected by external factors such as world market prices. Insights will be interpreted in terms of resilience of the local socio-ecological system.

Organic acids like itaconic and fumaric acid have a strong potential as building blocks to replaced naphtha-based chemicals. In the field of the proposal, Dutch industries hold a strong position as producers and as end users of the chemical building blocks. Also the Dutch biotech fermentation industry and the plant breeding industry have a world-wide strong position.

This proposal involves the modelling of the production of itaconic acid, a metabolic derivative of citric acid, and fumaric acid by Aspergillus niger and by a plant, potato (Solanum tuberosum).. The proposal relies on the strength of both production platforms; A. niger is the production organism for the fermentative production of citric acid. Existing industrial processes can easily adapted for the production of itaconic acid and fumaric acid. Starch potato is a low cost crop that is

already used for the production of starch for food and non-food applications. Preliminary experiments have shown significant production of itaconic acid after introduction of a microbial cis-aconitate decarboxylase.

The proposal involves the metabolic modelling of citric acid and itaconic acid production in A. niger based on transcript profiling, sub-cellular proteomics and sub-cellular metabolomics. Cellular imaging data would provide input into the model for cellular localization of enzyme activities and the sub-cellular pH at the side of action of the enzyme. This will provide unique input data to base the metabolic model on. By comparative modelling transcriptomics, proteomics and metabolomics data from Aspergillus terreus, Rhizopus oryzae and potato will be used to determine the metabolic

differences in these organisms and to redesign A. niger and potato for the efficient production of itaconic acid and fumaric acid.

Essentially the data needed for this modelling comes from matching projects. These projects already have been granted, guaranteeing the input of data to make the project successful. Also these projects involve essential collaborations to implement the necessary methodology efficiently.