Enhanced Exoelectrogenic Activity of Cupriavidus metallidurans in Bioelectrochemical Systems through the Expression of a Constitutively Active Diguanylate Cyclase

Alviz-Gazitua, Pablo; Espinoza-Tofalos, Anna; Formicola, Francesca; Guiliani, Nicolas; Turner, Raymond J.; Franzetti, Andrea; Seeger, Michael


Electroactive bacteria have a wide range of applications, including electricity production, bioremediation, and the sensing of toxic compounds. Bacterial biofilm formation is often mediated by the second messenger cyclic guanosine monophosphate (c-di-GMP) synthesized by a diguanylate cyclase (DGC). The role of c-di-GMP in the expression of c-type cytochromes has been previously reported. The aim of this study was to determine the bioelectrogenic activity of Cupriavidus metallidurans strain CH34 pJBpleD*, which possesses a constitutively active DGC that increases c-di-GMP levels. Notably, the heterologous expression of the constitutively active DGC in C. metallidurans strain CH34 pJBpleD* showed a higher biofilm formation and increased the electrical current production up to 560%. In addition, C. metallidurans CH34 pJBpleD* showed increased levels of c-type cytochrome-associated transcripts compared with the wild-type strain CH34. Scanning electron microscopies revealed a denser extracellular matrix with an increased exopolymeric substance content in the CH34 pJBpleD* biofilm on the electrode surface. The results of this study suggest that higher levels of c-di-GMP synthesized by a constitutively active diguanylate cyclase in C. metallidurans strain CH34 pJBpleD* activated the formation of an electroactive biofilm on the electrode, enhancing its exoelectrogenic activity.

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Título según WOS: ID WOS:000832017200001 Not found in local WOS DB
Título de la Revista: ENVIRONMENTS
Volumen: 9
Número: 7
Editorial: MDPI
Fecha de publicación: 2022


Notas: ISI