title: Systematic investigation and microbial community profile of indole degradation processes in two aerobic activated sludge systems.
abstract: Indole is widely spread in various environmental matrices. Indole degradation by bacteria has been reported previously, whereas its degradation processes driven by aerobic microbial community were as-yet unexplored. Herein, eight sequencing batch bioreactors fed with municipal and coking activated sludges were constructed for aerobic treatment of indole. The whole operation processes contained three stages, i.e. stage I, glucose and indole as carbon sources; stage II, indole as carbon source; and stage III, indole as carbon and nitrogen source. Indole could be completely removed in both systems. Illumina sequencing revealed that alpha diversity was reduced after indole treatment and microbial communities were significantly distinct among the three stages. At genus level, Azorcus and Thauera were dominant species in stage I in both systems, while Alcaligenes, Comamonas and Pseudomonas were the core genera in stage II and III in municipal sludge system, Alcaligenes and Burkholderia in coking sludge system. In addition, four strains belonged to genera Comamonas, Burkholderia and Xenophilus were isolated using indole as sole carbon source. Burkholderia sp. IDO3 could remove 100 mg/L indole completely within 14 h, the highest degradation rate to date. These findings provide novel information and enrich our understanding of indole aerobic degradation processes.
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Ma
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Qu
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Xuwang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Ziyan
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Huijie
authors.initials: H
authors.lastname: Li
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Zhaojing
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Jingwei
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Wenli
authors.initials: W
authors.lastname: Shen
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Jiti
authors.initials: J
authors.lastname: Zhou
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics; D001673:Biodegradation, Environmental; D019149:Bioreactors; D002244:Carbon; D005947:Glucose / Q000378:metabolism; D007211:Indoles / Q000378:metabolism*; D054892:Metagenome; D056186:Metagenomics; D064307:Microbiota; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology*
chemical_list: D007211:Indoles; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D002244:Carbon; C030374:indole; D005947:Glucose