Scientists at Washington University in St. Louis have made a significant discovery in the quest for sustainable bioplastics. Two new studies reveal that purple bacteria, a type of microorganism, have the potential to produce high-quality bioplastics, offering a promising solution to the world’s growing demand for eco-friendly plastics.
In the first study, researchers led by graduate student Eric Conners found that two previously unknown species of purple bacteria, Rhodomicrobium, can naturally produce polyhydroxyalkanoates (PHAs), a type of natural polymer that can be refined into plastic. The bacteria’s ability to produce PHAs is a game-changer, as it can be done without adding CO2 to the atmosphere and the polymers are completely biodegradable.
The second study, led by research lab supervisor Tahina Ranaivoarisoa, showed that genetic engineering can significantly increase the production of PHAs in a well-studied species of purple bacteria, Rhodopseudomonas palustris TIE-1. By inserting a gene that enhances the enzyme RuBisCO, the researchers were able to boost the bacteria’s PHA production to impressive levels.
The purple bacteria’s unique properties make them an attractive candidate for producing bioplastics. Unlike other bacteria, these microbes form interconnected networks that allow them to produce PHAs indefinitely. Additionally, their ability to capture carbon dioxide from air and water using energy from the sun makes them a sustainable option.
The findings of these studies offer hope for the development of more sustainable bioplastics. “There’s a huge global demand for bioplastics, and we’re excited to explore the potential of these purple bacteria as a source of this valuable material,” said Dr. Arpita Bose, associate professor of biology and corresponding author of the studies.
The researchers plan to continue studying the quality and possible uses of the polymers produced in their lab, with hopes of creating real solutions for the future. As one of the researchers noted, “We haven’t come close to realizing their potential” – suggesting that there is still much to be discovered about these remarkable microorganisms.
