Applied Microbiology and Biotechnology

, Volume 103, Issue 3, pp 1535–1544 | Cite as

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

  • Xi Liu
  • Shiwei Wang
  • Anming Xu
  • Li Zhang
  • Hongsheng Liu
  • Luyan Z. MaEmail author
Bioenergy and biofuels


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 PaPilA1–61 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.


Microbial nanowires Type IV pili (T4P) PilA Pseudomonas aeruginosa Extracellular electron transfer (EET) Microbial fuel cells (MFC) 



We sincerely thank Dr. Mohamed Y. El-Naggar and Dr. Sahand Pirbadian at the University of Southern California for the helpful comments on the manuscript and the CP-AFM experiments respectively, Dr. Daniel J. Wozniak at the Ohio State University for the anti-PaPilA antibody, Dr. Anhuai Lu and Dr. Hongrui Ding at the Peking University for the MFC configuration, Dr. Cong Liu at the Jiangsu Normal University for the G. sulfurreducens PCA strain, and Dr. Qing Wei at the Institute of Microbiology, Chinese Academy of Sciences for the manuscript preparation.


This study was funded by the National Basic Research Program of China (973) (2014CB846002 for LM) and by the National Natural Science Foundation of China (31570126 to LM and 31770152 to SW).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This article does not contain studies with human participants or animals performed by any of the authors.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.State Key Laboratory of Microbial Resources, Institute of MicrobiologyChinese Academy of SciencesBeijingChina
  2. 2.University of Chinese Academy of SciencesBeijingChina
  3. 3.Liaoning UniversityShenyangChina

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