iGEM TU Darmstadt 2015
"Building with light opens up a spectrum of opportunities, especially if you can build in three dimensions. Why not use this potential to help people in need?"
Our project combined very different ideas from various fields of study into one massive interdisciplinary project. Aspects of computational engineering, additive manufacturing and of course synthetic biology were combined into our project:
‘Building with light - TU Darmstadt 2015’
Last year we were able to reduce the amount of money we spend on lab materials by printing gel chambers with a 3D-printer, as well as several other open hardware devices. This year we went even further and decided to assemble a functional stereolithography 3D-printer from scratch while also biotechnologically producing our own resin.
We established genetic pathways via metabolic engineering in E. coli that allow the bacterium to produce various chemicals that can be used for 3D-printing purposes, namely ethylene glycol, itaconic acid and xylitol. Our team also kept working on parts from previous years and provided the registry with an improved version of a protein scaffold. By fixing proteins in close physical proximity to each other on a scaffold, we could increase their metabolic output significantly.
During our project we built our own 3D-printer, whose total building costs lay below $1000. The most expensive piece of our printer is a UV light emitting projector. A mirror redirects the desired picture onto the UV permeable bottom of the basin in which our liquid resin is situated. The resin polymerises layer by layer on a platform which rises slowly out of the basin as the printing proceeds. This means that the print-outs are being produced upside down in a so-called “bottom up” approach. It was planned that a raspberry Pi can wirelessly receive the 3D model plans and operate the motor of the rising platform and the projector accordingly. Plenty of the parts used in the construction of our printer were designed by us and custom produced in the FabLab of the TU Darmstadt by a FDM-3D-printer. As our printer has a simple basic construction plan, it can easily be reproduced by anyone.
The laboratory work was supported by the modeling group which developed membrane simulations for a xylose transporter (xylE) and computational structure prediction techniques to design a hokD kill-switch for our bacteria. In the process, we developed a new structure prediction technique based on an artificial neural network and implemented a genetic algorithm to design arbitrary RNA riboswitches. We made the program available to the community as a web service hosted on our server.
Besides working in the laboratory, the engineering workshop (FabLab Darmstadt) and the computer pool, we collaborated with our partner Synenergene. Together we developed an application scenario which focuses on the interdependency of our scheduled project with the community, and how both parties can be affected by each other. Thereby we were able to optimize our project according to the needs of the general public.
In conclusion, we are proud to present the iGEM community and the rest of the world the achievements of this year’s project. We provide:
- a self-assembled stereolithographic 3D-printer together with its detailed construction plans and software
- the genetic parts for the biotechnological production of a photocurable resin, usable in our printer, from cheap and commonly available starting materials
- a plastic resulting from the polymerization of our resin which is harm-free to humans as well as biodegradable, hence proving eco-friendly
- free, web-based software to design RNA riboswitches suitable for your own projects
- a free, social portal to enable networking and contact keeping inside of the community, whether you are an active participants or an alumni.
We propose a possible application for our printer in the making of inexpensive, custom and on the spot made prostheses, in the relief of humanitarian or natural catastrophes.