With global battery markets expected to reach $86.6 billion by 2018, environmental concerns around their production and disposal are grave. Scientists at UEA are helping to understand how clean energy may be generated with help from a surprising source - bacteria.
From smartphones to laptops the use of portable technology is widespread – and synonymous with its use are the batteries that power them. With a booming global consumer electronics industry - mobile phone subscriptions alone now reach almost 7 billion - battery consumption is only going to escalate.
Batteries work by turning chemical energy into electrical energy, providing an easy, portable source of power but their production and disposal can lead to serious environmental damage, from the impact of mining minerals to the pollution caused by their incorrect disposal.
Biochemical scientists at UEA are looking to understand how, in the right environment, bacteria can actually generate electricity, something that could provide alternative solutions to powering the world’s technology.
Unlike humans, many micro-organisms can survive without oxygen and some bacteria survive by ‘breathing rocks’ – especially minerals of iron.
The bacteria take fuel molecules from the natural environment into their cell interior and combust them to make energy. A side product of this reaction is a flow of electricity that can be delivered back across the bacterial outer cell membrane to rocks in the natural environment – or to graphite electrodes in fuel cells.
This means that the bacteria can transmit an electrical charge from inside the cell out to the mineral much like the neutral wire in a household plug.
Professor Julea Butt from UEA’s School of Chemistry and School of Biological Sciences is uncovering how the bacterial cells transfer electrical charge and exactly how they move electrons from the inside to the outside of a cell over distances as small as tens of nanometres.
The research team looked at proteins called ‘multi-haem cytochromes’ contained in ‘rock breathing’ bacteria such as species of Shewanella.
The research, funded by the BBSRC and performed in collaboration with University College London and the Pacific Northwest National Laboratory USA, shows that proteins conduct electricity by positioning metal centres – known as haems - to act in a similar way to stepping stones by allowing electrons to hop through an otherwise electrically insulating structure.
By understanding how this natural process works UEA scientists hope to inspire the design of bespoke proteins which will underpin microbial fuel cells for sustainable energy production.
HOW WILL YOU POWER CHANGE?
Professor Julea Butt
Professor of Biophysical Chemistry
School of Biological Sciences, School of Chemistry
My research focuses on gaining greater insight into the cellular roles of redox proteins to inform their exploitation in biotechnologies.