Wang, Victor Bochuan2; Chua, Song-Lin3; Cao, Bin3; Seviour, Thomas3; Nesatyy, Victor J3; Marsili, Enrico3; Kjelleberg, Staffan3; Givskov, Michael5; Tolker-Nielsen, Tim5; Song, Hao3; Loo, Joachim Say Chye3; Yang, Liang4
1 Department of Immunology and Microbiology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Københavns Universitet2 Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore, Singapore.3 unknown4 Center for Systems Microbiology5 Department of Immunology and Microbiology, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Københavns Universitet
The biosynthesis of the redox shuttle, phenazines, in Pseudomonas aeruginosa, an ubiquitous microorganism in wastewater microflora, is regulated by the 2-heptyl-3,4-dihydroxyquinoline (PQS) quorum-sensing system. However, PQS inhibits anaerobic growth of P. aeruginosa. We constructed a P. aeruginosa strain that produces higher concentrations of phenazines under anaerobic conditions by over-expressing the PqsE effector in a PQS negative ΔpqsC mutant. The engineered strain exhibited an improved electrical performance in microbial fuel cells (MFCs) and potentiostat-controlled electrochemical cells with an approximate five-fold increase of maximum current density relative to the parent strain. Electrochemical analysis showed that the current increase correlates with an over-synthesis of phenazines. These results therefore demonstrate that targeting microbial cell-to-cell communication by genetic engineering is a suitable technique to improve power output of bioelectrochemical systems.
Plos One, 2013, Vol 8, Issue 5
Bioelectric Energy Sources; Biofilms; Biosynthetic Pathways; Electricity; Genetic Engineering; Hydroxyquinolines; Phenazines; Pseudomonas aeruginosa; Pyocyanine; Quorum Sensing