Pyrosequencing Reveals a Core Community of Anodic Bacterial Biofilms in Bioelectrochemical Systems from China.

Yong Xiao,Yue Zheng,Song Wu,Peng Liang,Zhao-Hui Yang,Feng Zhao,Xia Huang,I-Son Ng,Bor-Yann Chen,Zheng Chen,En-Hua Zhang

doi:10.3389/fmicb.2015.01410

Abstract

Bioelectrochemical systems (BESs) are promising technologies for energy and product recovery coupled with wastewater treatment, and the core microbial community in electrochemically active biofilm in BESs remains controversy. In the present study, 7 anodic communities from 6 bioelectrochemical systems in 4 labs in southeast, north and south-central of China are explored by 454 pyrosequencing. A total of 251,225 effective sequences are obtained for 7 electrochemically active biofilm samples at 3% cutoff level. While Alpha-, Beta-, and Gamma-proteobacteria are the most abundant classes (averaging 16.0–17.7%), Bacteroidia and Clostridia are the two sub-dominant and commonly shared classes. Six commonly shared genera i.e., Azospira, Azospirillum, Acinetobacter, Bacteroides, Geobacter, Pseudomonas, and Rhodopseudomonas dominate the electrochemically active communities and are defined as core genera. A total of 25 OTUs with average relative abundance >0.5% were selected and designated as core OTUs, and some species relating to these OTUs have been reported electrochemically active. Furthermore, cyclic voltammetry and chronoamperometry tests show that two strains from Acinetobacter guillouiae and Stappia indica, bacteria relate to two core OTUs, are electrochemically active. Using randomly selected bioelectrochemical systems, the study has presented extremely diverse bacterial communities in anodic biofilms, though, we still can suggest some potentially microbes for investigating the electrochemical mechanisms in bioelectrochemical systems.

Highlights

Bioelectrochemical systems (BESs) are promising technologies for energy and products recovery coupled with wastewater treatment and have attracted increasing attention (Liu and Logan, 2004; Lovley, 2006a; Zhao et al, 2009b; Liu et al, 2013)
The understanding of performance of electrochemically active biofilm (EAB), which consists of Electrochemically active microorganisms (EAMs) and other microorganisms, is still poor due to limited knowledge on the microbial community in EAB
After filtering the low quality reads and trimming adapters and barcodes, a total of 266,791 high quality reads were obtained for the 7 EAB samples using Quantitative Insights Into Microbial Ecology (QIIME) (Table S1)

Summary

Introduction

Bioelectrochemical systems (BESs) are promising technologies for energy and products recovery coupled with wastewater treatment and have attracted increasing attention (Liu and Logan, 2004; Lovley, 2006a; Zhao et al, 2009b; Liu et al, 2013). Geobacter was detected as the most dominant microorganisms in anodic community by low depth pyrosequencing (Lee et al, 2010; Miceli et al, 2012; Yates et al, 2012).

Results

Conclusion