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Team:Wageningen UR/Summary
From 2013.igem.org
- Safety introduction
- General safety
- Fungi-related safety
- Biosafety Regulation
- Safety Improvement Suggestions
- Safety of the Application
Summary
We made mistakes,
though this whole endeavor was incredibly worthwhile.
We learned a lot,
and nothing beats the excitement of positive results.
-- Wageningen UR 2013 iGEM students
Concluding our iGEM project in 2013, we introduced Aspergillus niger as a potential host into iGEM. It is an industrially relevant organism, deserving a place in iGEM as a standard synthetic biology chassis. With the host engineering, we stepped further to the next level of synthetic biology.
In this GRAS organism, we established a modular system of domain shuffling in order to express a variety of secondary metabolites. We focused on the production of a medically relevant compound, lovastatin, which has never been produced in A. niger.We synthesized a range of modules for the main multi-domain enzyme in the lovastatin pathway. We also developed a new frameshiftless assembly protocol to design new multidomain enzyme complexes, and bricked these parts for future teams.
Additionally, to target the production in a specific compartment, a toolkit including a promoter, terminator, biosensors for pH, ATP, and chromogenic biomarkers, as well as a marker for the cytoskeleton was created. It paved the way for future teams to further exploit this beautiful bug. Furthermore, the metabolic models we developed to pre-emptively assess the production conditions, and potentially the optimization of production, has hinted at future improvements for A. niger lovastatin production.
Finally, we modified the host by directed evolution. Filamentous fungi are pretty organisms, but multicellularity is not always wanted in fermentations. We set out to investigate it by evolving mutants with a reduced mycelial cohesiveness. Microscopic analyses have shown that Aspergillus is conditionally dimorphic, and both viable and metabolically active in a single cell morphotype. We made important steps in unravelling the causes of multicellularity.
All in all, our project has been ambitious, inspiring, educational, social, and totally worthwhile. We made mistakes, underestimated some experimental time frames, totally failed in some experimental set ups, but nothing beats the excitement of positive results.
