Biological synthesis of high-conductive pili in aerobic bacterium Pseudomonas aeruginosa

• Published in: Applied microbiology and biotechnology 2019-02, Vol.103 (3), p.1535-1544
• Main Authors: Liu, Xi, Wang, Shiwei, Xu, Anming, Zhang, Li, Liu, Hongsheng, Ma, Luyan Z.
• Format: Article
• Language: English
• Subjects: Amino acids; Bacteria; Biochemical fuel cells; Bioelectricity; Bioenergy and Biofuels; Biofilms; Biomedical and Life Sciences; Biosynthesis; Biotechnology; Carbenicillin; Conductivity; Fasciculation; Fuel cells; Fuel technology; Life Sciences; Methods; Microbial Genetics and Genomics; Microbiology; Microorganisms; N-Terminus; Nanomaterials; Nanotechnology; Nanowires; Organelles; Physiological aspects; PilA protein; Pili; Proteins; Pseudomonas aeruginosa; Twitching
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-018-9484-5

Bioelectrical nanowires as ecomaterials have great potential on environmental applications. A wide range of bacteria can express type IV pili (T4P), which are long protein fibers assembled from PilA. The T4P of Geobacter sulfurreducens are well known as “microbial nanowires,” yet T4P of Pseudomonas aeruginosa (PaT4P) was believed to be poorly conductive. P. aeruginosa is an aerobic and electrochemically active bacterium. Its T4P have been known to be responsible for surface attachment, twitching motility and biofilm formation. Here, we show that PaT4P can be highly conductive while assembled by a truncated P. aeruginosa PilA (PaPilA) containing only N-terminus 61 amino acids. Furthermore, increasing the number of aromatic amino acids in the PaPilA 1–61 significantly enhances the conductivity of pili and the bioelectricity output of P. aeruginosa in microbial fuel cell system, suggesting a potential application of PaT4P as a conductive nanomaterial. The N-terminal region of PilA from diverse eubacteria is highly conserved, implying a general way to synthesize highly conductive microbial nanowires and to increase the bioelectricity output of microbial fuel cell.