From Eat to trEat : engineering the mitochondrial Eat1 enzyme for enhanced ethyl acetate production in Escherichia coli

Genetic engineering of microorganisms has become a common practice to establish microbial cell factories for a wide range of compounds. Ethyl acetate is an industrial solvent that is used in several applications, mainly as a biodegradable organic solvent with low toxicity. While ethyl acetate is produced by several natural yeast species, the main mechanism of production has remained elusive until the discovery of Eat1 in Wickerhamomyces anomalus. Unlike other yeast alcohol acetyl transferases (AATs), Eat1 is located in the yeast mitochondria, suggesting that the coding sequence contains a mitochondrial pre-sequence. For expression in prokaryotic hosts such as E. coli, expression of heterologous proteins with eukaryotic signal sequences may not be optimal. Results Unprocessed and synthetically truncated eat1 variants of Kluyveromyces marxianus and Wickerhamomyces anomalus have been compared in vitro regarding enzyme activity and stability. While the specific activity remained unaffected, half-life improved for several truncated variants. The same variants showed better performance regarding ethyl acetate production when expressed in E. coli. Conclusion By analysing and predicting the N-terminal pre-sequences of different Eat1 proteins and systematically trimming them, the stability of the enzymes in vitro could be improved, leading to an overall improvement of in vivo ethyl acetate production in E. coli. Truncated variants of eat1 could therefore benefit future engineering approaches towards efficient ethyl acetate production.publishedVersio

Data for: Using GPS tracking to understand the impact of management interventions on visitor densities and bird populations

Monitoring data of visitors of the New Forest, UK. Each track has been collected with an eTrex or eTrex Venture GPS device. Explanation of the headers can be found in Table A.3. The dataset contains 1563 tracks of which 1553 could be used for further analyses in our research

Model for Nature Policy - MNP : Automatisering validatie, automatisering draagkrachten, rekenmethode van de randvoorwaarden binnen MNP, gevoeligheids- en onzekerheidsanalyse

Model for Nature Policy – MNP: Automation of validation, automation of carrying capacities, calculation method for the boundary conditions within MNP and sensitivity and uncertainty analysis. The Model for Nature Policy (MNP, MetaNatuurPlanner) is used by the Netherlands Environmental Assessment Agency (PBL) and others for model simulations to estimate long-term persistence of species and the conservation status of plant and animal species in the Netherlands. The calculated indicator is considered to be a proxy for the degree of achievement of the objectives of the Birds and Habitats Directives. The model is used for calculating a number of Environmental Data Compendium (CLO) indicators and is routinely used for the Assessment of the Dutch Living Environment and the National Nature Outlook. The MNP is therefore constantly being further developed to keep up with new questions from policymakers and scientific requirements. This report describes four technical developments: automation of validation, automation of carrying capacities, calculation method for the abiotic boundary conditions within the MNP and the uncertainty and sensitivity analysis

From Eat to trEat : engineering the mitochondrial Eat1 enzyme for enhanced ethyl acetate production in Escherichia coli

Genetic engineering of microorganisms has become a common practice to establish microbial cell factories for a wide range of compounds. Ethyl acetate is an industrial solvent that is used in several applications, mainly as a biodegradable organic solvent with low toxicity. While ethyl acetate is produced by several natural yeast species, the main mechanism of production has remained elusive until the discovery of Eat1 in Wickerhamomyces anomalus. Unlike other yeast alcohol acetyl transferases (AATs), Eat1 is located in the yeast mitochondria, suggesting that the coding sequence contains a mitochondrial pre-sequence. For expression in prokaryotic hosts such as E. coli, expression of heterologous proteins with eukaryotic signal sequences may not be optimal. Results Unprocessed and synthetically truncated eat1 variants of Kluyveromyces marxianus and Wickerhamomyces anomalus have been compared in vitro regarding enzyme activity and stability. While the specific activity remained unaffected, half-life improved for several truncated variants. The same variants showed better performance regarding ethyl acetate production when expressed in E. coli. Conclusion By analysing and predicting the N-terminal pre-sequences of different Eat1 proteins and systematically trimming them, the stability of the enzymes in vitro could be improved, leading to an overall improvement of in vivo ethyl acetate production in E. coli. Truncated variants of eat1 could therefore benefit future engineering approaches towards efficient ethyl acetate production

Natuurverkenning 2050 – Scenario Natuurinclusief

If the Netherlands were to adopt a nature-inclusive planning regime this could make a significant contribution towards resolving the current challenges facing Dutch society. This is the outcome of the analysis of the Nature- Inclusive scenario, one of the three scenarios in the National Nature Outlook 2050. In this scenario there is an increase in the provision of multiple ecosystem services that make important contributions to meeting the major challenges facing society in the areas of climate, biodiversity, water quality and the quality of the human environment. It is the first time that the effects of a nature-inclusive future have been quantified in this way for the Netherlands. But even a far-reaching nature-inclusive spatial development of the Netherlands would still leave issues to be resolved and additional measures would be needed to fully overcome these societal challenges. Moreover, nature-inclusive spatial development would involve major changes not only in spatial planning and design, but also in people’s behaviour