title: Identification of Comamonas testosteroni as an androgen degrader in sewage.
abstract: Numerous studies have reported the masculinization of freshwater wildlife exposed to androgens in polluted rivers. Microbial degradation is a crucial mechanism for eliminating steroid hormones from contaminated ecosystems. The aerobic degradation of testosterone was observed in various bacterial isolates. However, the ecophysiological relevance of androgen-degrading microorganisms in the environment is unclear. Here, we investigated the biochemical mechanisms and corresponding microorganisms of androgen degradation in aerobic sewage. Sewage samples collected from the Dihua Sewage Treatment Plant (Taipei, Taiwan) were aerobically incubated with testosterone (1 mM). Androgen metabolite analysis revealed that bacteria adopt the 9, 10-seco pathway to degrade testosterone. A metagenomic analysis indicated the apparent enrichment of Comamonas spp. (mainly C. testosteroni) and Pseudomonas spp. in sewage incubated with testosterone. We used the degenerate primers derived from the meta-cleavage dioxygenase gene (tesB) of various proteobacteria to track this essential catabolic gene in the sewage. The amplified sequences showed the highest similarity (87-96%) to tesB of C. testosteroni. Using quantitative PCR, we detected a remarkable increase of the 16S rRNA and catabolic genes of C. testosteroni in the testosterone-treated sewage. Together, our data suggest that C. testosteroni, the model microorganism for aerobic testosterone degradation, plays a role in androgen biodegradation in aerobic sewage.
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.|Department of Life Science, National Taiwan Normal University, Taipei, 106, Taiwan.|Biodiversity Program, Taiwan International Graduate Program, Academia Sinica and National Taiwan Normal University, Taipei, 115, Taiwan.
authors.forename: Yi-Lung
authors.initials: YL
authors.lastname: Chen
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.
authors.forename: Chia-Hsiang
authors.initials: CH
authors.lastname: Wang
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.
authors.forename: Fu-Chun
authors.initials: FC
authors.lastname: Yang
authors.affiliation: Environmental Biotechnology Program, Life Sciences Department, College of Graduate Studies, Arabian Gulf University, Manama, 26671, Kingdom of Bahrain.
authors.forename: Wael
authors.initials: W
authors.lastname: Ismail
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.
authors.forename: Po-Hsiang
authors.initials: PH
authors.lastname: Wang
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.
authors.forename: Chao-Jen
authors.initials: CJ
authors.lastname: Shih
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 115, Taiwan.
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Wu
authors.affiliation: Biodiversity Research Center, Academia Sinica, Taipei, 115, Taiwan.|Department of Life Science, National Taiwan Normal University, Taipei, 106, Taiwan.|Biodiversity Program, Taiwan International Graduate Program, Academia Sinica and National Taiwan Normal University, Taipei, 115, Taiwan.
authors.forename: Yin-Ru
authors.initials: YR
authors.lastname: Chiang
mesh_terms: D000332:Aerobiosis; D000728:Androgens / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics; D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D020604:Comamonas testosteroni / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D017931:DNA Primers; D056186:Metagenomics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology*; D013624:Taiwan; D053719:Tandem Mass Spectrometry; D013739:Testosterone / Q000378:metabolism
chemical_list: D000728:Androgens; D001426:Bacterial Proteins; D017931:DNA Primers; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D013739:Testosterone