Summary of the role of pyocyanin in the transformation and biodegradation of Polycyclic Aromatic Hydrocarbons

Abstract

Pyocyanin is an active redox phenazine of intense blue color and specific to Pseudomonas aeruginosa. The synthesis of the molecule confers different benefits to the bacterium. Pyocyanin can control its growth and persistence in environments with high nutritional pressures, forming biofilms. As well, synthesis of pyocyanin enables P. aeruginosa tolerate and uptake highly toxic compounds such as polycyclic aromatic hydrocarbons (PAHs), considered the most dangerous compounds among all molecules found in crude oil and petroderivatives. Additionally, pyocyanin increases the bioavailability of PAHs and its metabolites are used to synthetize crucial molecules for the biodegradation of other PAHs. On the other hand, oil hydrocarbons can serve as oxygen vectors during the synthesis of pyocyanin, contributing to the sustainability of the biodegradation process. This review is a compilation of recent advances reported in the literature about the relationship between pyocyanin expression and the hydrocarbonoclastic activity of P. aeruginosa. This characteristic, for the pyocyanin-deficient strains, is important for the degradation of PAHs, a topic that has been unevenly studied.