Team:London BioHackspace

Project Description: JuicyPrint

What is JuicyPrint?

JuicyPrint will be a 3d printer that can be fed with fruit juice and can be used to print out useful shapes made of bacterial cellulose, a strong and exceptionally versatile biopolymer.

Why bacterial cellulose?

Bacterial cellulose is a biopolymer that is very similar to the fibre found in plants. The only difference is that bacterial cellulose is much purer and is made of randomly criss-crossed fibres compared with the regular ‘grain’ of plant cellulose. Paper made from bacterial cellulose is much smoother than normal paper and is currently used in ultra-high end speakers to produce cleaner sound.

Bacterial cellulose is not only physically strong, but it is biocompatible meaning it can be used in all sorts of clinical applications. Flat sheets of bacterial cellulose are already used in some forms of skin graft therapy and with JuicyPrint’s ability to print 3d structures, it will be possible to create effective tissue scaffolds for tissue engineering applications such as the growing of replacement organs.

How does it work?

The heart of JuicyPrint is our genetically engineered strain of the cellulose producing bacteria Gluconacetobacter hansenii (G. hansenii). G. hansenii (sometimes referred to as Acetobacter) is normally found growing in vinegar and is used in China to make a fermented tea called kombucha. G. hansenii can use lots of different liquids, such as fruit juice and beer brewing waste, as a food source, so almost anyone can grow them!

We are planning to insert genes that will let us switch on or switch off the cellulose production of the bacteria using light. Naturally occuring G. hansenii will produce a cellulose ‘pancake’ along the surface of the liquid nutrients they are grown in. But when a pattern of light is shined on the surface of a liquid culture of our engineered strain, only the bacteria in the dark patches will make cellulose so we can make the cellulose pancake any shape we want.

We can then push the patterned layer of cellulose below the surface and project a new pattern of light onto the culture. If we repeat this process a three dimensional structure will be built up out of the numerous patterned layers.