Cyanobacteria are a diverse group of photosynthetic prokaryotes, major primary producers, and the ancestors of the chloroplast. These microorganisms played an essential role in the evolution of Early Earth and the biosphere. Nowadays, cyanobacteria are considered a promising biological alternative to overcome the increasing demand for sustainable biofuels and bioplastics. Despite their relevance, cyanobacteria still present several undefined genomic and metabolic features.

Beta-oxidation is one of those features that remain elusive in cyanobacteria. This mechanism of fatty acids (FAs) degradation had been thought to be universal for all organisms. Nevertheless, some studies have suggested that beta-oxidation might be lacking in cyanobacteria, despite the scattered evidence to support this hypothesis. Recently, we exploited this apparent lack of a canonical beta-oxidation pathway to develop a strategy for detecting new natural products that incorporate FA residues. However, this work revealed an unexpected finding that could support an alternative FA catabolic pathway, namely an extensive deuterium abstraction pattern in the lipids after perdeuterated FA supplementation of some cyanobacterial strains. With CyanoBOX project we propose to carry out critical experimentation and bioinformatic analyses to clarify if cyanobacteria indeed lack the beta-oxidation pathway. Additionally, this exploratory project will allow to address several questions related with cyanobacteria evolution and bring knowledge that, ultimately, can lead to more efficient metabolism to be applied for biotechnological purposes.