New cyborg bacteria covered in solar cells can help spawn clean fuels

22 Aug 2017

Scientist checking bacteria in petri dish (not involved with this research). Image: Khamkhlai Thanet/Shutterstock

Offering another glimpse into the wondrous near future, cyborg bacteria are now being used to harvest solar energy.

Scientists often turn to nature to help solve some of our greatest scientific problems but, when it comes to harnessing solar energy, nature has a lot to do to catch up with the latest in bioengineering.

One such example is a new breakthrough achieved by researcher Kelsey Sakimoto who has engineered cyborg bacteria covered in tiny, highly-efficient solar panels that ‘outshine’ natural photosynthesis.

Presenting his findings at a recent meeting of the American Chemical Society, Sakimoto from the University of California, Berkeley has focused on ‘supercharging’ organisms such as bacteria with inorganic semiconductors to produce useful chemicals from carbon dioxide and water.

In this instance, he worked with a nonphotosynthetic bacterium called Moorella thermoacetica, which naturally produces acetic acid from CO2.

Acetic acid is considered a hugely useful chemical as it can be readily upgraded to a number of fuels, polymers, pharmaceuticals and commodity chemicals, with help from complementary, genetically engineered bacteria.

A zero-waste technology

To create the solar panels, Sakimoto and his team fed cadmium and the amino acid cysteine to the bacteria, and synthesised cadmium sulphide nanoparticles, which function as the solar panels.

Once functional, the supercharged bacteria produces acetic acid from CO2, water and light at an efficiency of more than 80pc.

Even more impressive is the fact that the early findings show the process to be self-replicating and self-regenerating, making this a zero-waste technology.

“Synthetic biology and the ability to expand the product scope of CO2 reduction will be crucial to poising this technology as a replacement, or one of many replacements, for the petrochemical industry,” Sakimoto said.

While there is still some way to go before it could be deemed commercially available, Sakimoto is optimistic about its potential. “Our algal biofuels are much more attractive, as the whole CO2-to-chemical apparatus is self-contained and only requires a big vat out in the sun.”

Colm Gorey was a senior journalist with Silicon Republic

editorial@siliconrepublic.com