About This Project

We aim to create a novel biological chassis that exploits both fermentative and photosynthetic pathways for biohydrogen gas production. By genetically engineering hydrogenases from Chlamydomonas reinhardtii and Pyrococcus furiosus into Rhodobacter sphaeroides, we will direct more reducing power towards hydrogen synthesis. Ultimately, we aim to harness biohydrogen as a more cost effective and environmentally friendly fuel source.

Ask the Scientists

What is the context of this research?

Current hydrogen production involves natural gas remediation, which renders hydrogen a non-renewable resource. Biohydrogen production using waste resources is a green alternative, however current rates are too low to be a economically feasible. Our idea to improve photo-fermentative pathways came after researching drawbacks of co-culture experiments. By manipulating the innate metabolism of R. sphaeroides we will direct more reducing power towards biohydorgen production. Finally, our further aims to build combined home heating units were inspired by the designs of iGEM Team Macquarie 2017 and cost considerations from Energy Action Scotland.

What is the significance of this project?

The Hydrogen Economy is poised to be an alternative to fossil fuel, but major production methods are expensive and non-renewable.

R. sphaeroides produces hydrogen using organic sugars. Research into enhancing this have involved gene knockouts and co-cultures. We want to explore a different route by combining photo-fermentation and dark fermentation. If successful, we will have an organism, powered by sunlight, with greater yield than wild type. This also eliminates the difficulties of sustaining co-cultures.

Unsuccessful, we will still gain a better molecular understanding of the bacterium's metabolism, and how we could potentially manipulate it. Future research could improve on our project and create a more cost effective source of biohydrogen.

What are the goals of the project?

We hypothesize that by introducing hydrogenase enzymes into R. sphaeroides we will produce biohydrogen at a yield higher than its natural rate. We will be using 2 different hydrogenases, and our experiments will compare the hydrogen production rates of these enzymes in separate cultures.

We will also test different waste effluents as carbon sources to further optimize our design, such as draff from whisky. Transformed R. sphaeroides strains grown in flasks will be attached to a water-filled cylinder, and hydrogen content will be determined by gas chromatography. Readings will be taken at regular time intervals and a standard rate will be calculated.

With this data, we aim to model these production rates to see how it could be implemented on an industrial scale.