title: Linkages of Firmicutes and Bacteroidetes populations to methanogenic process performance.
abstract: To identify potential linkages between specific bacterial populations and process performance in anaerobic digestion, the dynamics of bacterial community structure was monitored with high-throughput sequencing in triplicate anaerobic digesters treating animal waste. Firmicutes and Bacteroidetes were found as the two most abundant populations, however, with contrasting population dynamics in response to organic overloading. Firmicutes dominated the bacterial community during stable process performance at low organic loading rate, representing over 50 % of the bacterial abundance. In contrast, the onset of organic overloading raised the relative abundance of Bacteroidetes from 20 ± 2.6 to 44 ± 3.1 %. In addition to the significant negative correlation between the relative abundance of Firmicutes and Bacteroidetes, populations of Firmicutes and Bacteroidetes were found to be linked to process parameters including organic loading rate, volatile fatty acids concentration, and methane production. Therefore, the population abundance ratio of Firmicutes to Bacteroidetes (F/B ratio) was suggested as a potential indicator for process performance. The interactions between Firmicutes and Bacteroidetes populations could be exploited to develop strategies for the prevention of performance perturbation in anaerobic digestion processes.
authors.affiliation: Department of Civil and Environmental Engineering, The University of Tennessee, Knoxville, TN, 37996, USA.
authors.forename: Si
authors.initials: S
authors.lastname: Chen
authors.affiliation: Biology Institute, Hebei Academy of Sciences, Shijiazhuang, Hebei, China.
authors.forename: Huicai
authors.initials: H
authors.lastname: Cheng
authors.affiliation: Department of Civil and Environmental Engineering, The University of Tennessee, Knoxville, TN, 37996, USA.
authors.forename: Kristen N
authors.initials: KN
authors.lastname: Wyckoff
authors.affiliation: Department of Civil and Environmental Engineering, The University of Tennessee, Knoxville, TN, 37996, USA. qianghe@utk.edu.|Institute for a Secure and Sustainable Environment, The University of Tennessee, Knoxville, TN, USA. qianghe@utk.edu.
authors.forename: Qiang
authors.initials: Q
authors.lastname: He
mesh_terms: D000693:Anaerobiosis; D041963:Bacteroidetes / Q000378:metabolism*; D018533:Biomass; D004269:DNA, Bacterial / Q000302:isolation & purification; D005232:Fatty Acids, Volatile / Q000096:biosynthesis*; D005285:Fermentation; D000068536:Bacillota / Q000378:metabolism*; D007218:Industrial Microbiology; D008697:Methane / Q000096:biosynthesis*; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D005232:Fatty Acids, Volatile; D008697:Methane
keywords: Anaerobic digestion; Animal waste; Bacteroidetes; Firmicutes; Pyrosequencing