Winner: Chromatophores efficiently promote light-driven ATP synthesis and DNA transcription...

What is it about?

A major goal of synthetic biology is the construction of artificial protocells, which are self-organized lipid structures proposed to be precursors to cellular life. One challenge facing artificial protocells is how to autonomously generate energy to power internal processes. The authors of this study entrapped structures called chromatophores from purple nonsulfur bacteria (Rhodobacter sphaeroides) in giant lipid vesicles along with the necessary components for synthesis of ATP, the cellular energy currency, and for gene expression. The chromatophores acted as nanosized photosynthetic organelles, using light to synthesize ATP. In turn, the ATP fueled gene expression within the cells. The results show how bacterial chromatophores can fuel artificial cells for both biotechnological applications and studies on the origin of life on Earth.

Featured Image

Photo by CDC on Unsplash

Photo by CDC on Unsplash

Why is it important?

Chromatophores are closed vesicles extracted from photosynthetic bacteria that efficiently perform the photophosphorylation reaction (ADP + Pi → ATP) under illumination. Here we show that, when entrapped inside giant lipid vesicles, they behave as nano-biophotosynthetic organellae, allowing the construction of energetically autonomous artificial protocells. As proof of concept, DNA has been transcribed within an artificial protocell, thanks to the continuous ATP photo-production from chromatophores. Such a hybrid multicompartment approach will speed up the current efforts of constructing cell-like systems of increasing complexity, allowing the implementation of several ATP-dependent processes. Developed at the interface between synthetic biology and systems chemistry, the science of artificial protocells promises unprecedented biotechnological applications, as well as unveiling still unsolved origins-of-life questions.