Novel genetic tools to tackle c-di-GMP-dependent signalling in Pseudomonas aeruginosa

To develop new genetic tools for studying 3',5'-cyclic diguanylic acid (c-di-GMP) signalling in Pseudomonas aeruginosa.Plasmid pPcdrA::lux, carrying a transcriptional fusion between the c-di-GMP responsive promoter PcdrA and the luxCDABE reporter genes, has been generated and validated in purpose-built P. aeruginosa strains in which c-di-GMP levels can be increased or reduced upon arabinose-dependent induction of c-di-GMP synthetizing or degrading enzymes.The reporter systems described so far were able to detect a decrease in the c-di-GMP levels only in engineered strains overproducing c-di-GMP. Conversely, pPcdrA::lux could be used for studying any process or chemical compound expected to cause both an increase or a decrease with respect to the c-di-GMP levels produced by wild type P. aeruginosa. Another relevant aspect of this study has been the development of novel and improved genetic devices for the fine arabinose-dependent control of c-di-GMP levels in P. aeruginosa.The genetic tools developed and validated in this study could facilitate investigations tackling the c-di-GMP signalling process on different fields, from cellular physiology to drug-discovery research.