title: Enhancement of extracellular electron transfer and bioelectricity output by synthetic porin.
abstract: The microbial fuel cell (MFC), is a promising environmental biotechnology for harvesting electricity energy from organic wastes. However, low bacterial membrane permeability of electron shuttles is a limiting factor that restricts the electron shuttle-mediated extracellular electron transfer (EET) from bacteria to electrodes, thus the electricity power output of MFCs. To this end, we heterologously expressed a porin protein OprF from Pseudomonas aeruginosa PAO1 into Escherichia coli, which dramatically increased its membrane permeability, delivering a much higher current output in MFCs than its parental strain (BL21). We found that the oprF-expression strain showed more efficient EET than its parental strain. More strikingly, the enhanced membrane permeability also rendered the oprF-expression strain an efficient usage of riboflavin as the electron shuttle, whereas its parental strain was incapable of. Our results substantiated that membrane permeability is crucial for the efficient EET, and indicated that the expression of synthetic porins could be an efficient strategy to enhance bioelectricity generation by microorganisms (including electrogenic bacteria) in MFCs.
authors.affiliation: Laboratory of Bioelectron based Biorefinery, Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang, Jiangsu Province 212013, China.
authors.forename: Yang-Chun
authors.initials: YC
authors.lastname: Yong
authors.forename: Yang-Yang
authors.initials: YY
authors.lastname: Yu
authors.forename: Yun
authors.initials: Y
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Jing-Yuan
authors.initials: JY
authors.lastname: Wang
authors.forename: Hao
authors.initials: H
authors.lastname: Song
mesh_terms: D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D019149:Bioreactors / Q000382:microbiology; D002463:Cell Membrane Permeability; D004579:Electron Transport; D004926:Escherichia coli / Q000235:genetics; D005110:Extracellular Space / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; C547605:OprF protein, Pseudomonas aeruginosa; D011994:Recombinant Proteins