title: Evaluation of simultaneous autotrophic and heterotrophic denitrification processes and bacterial community structure analysis.
abstract: This study demonstrated that a combined heterotrophic and autotrophic denitrification (HAD) process is highly effective for the simultaneous removal of acetate, nitrate, and sulfide at an efficiency of 100, 80, and 100 %, respectively. In the HAD system, simultaneous sulfide, acetate, and nitrate removals were observed, which indicated that heterotrophic and autotrophic denitrification occurred simultaneously. When the sulfide was existed in HAD reactor, the main product of sulfide biooxidation was S(0). Once the sulfide was exhausted, the sulfate concentration in the HAD reactor increased and became the main end product. These results provided an alternative method to control the end sulfide biooxidation product by online monitoring sulfide concentration. Nearly half (43 %) of the total clones in our mix-trophic reactor were amphitrophy denitrifiers. The autotrophic denitrifiers, heterotrophic denitrifiers, and amphitrophy denitrifiers coexisted in the HAD reactor to complete the denitrification process. Retrieved bacterial 16S rRNA gene clones affiliated with uncultured Xanthomonadaceae, Thauera, Thiobacillus, and Chromatiales were dominant.
authors.affiliation: Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
authors.forename: Guihua
authors.initials: G
authors.lastname: Xu
authors.forename: Jingjing
authors.initials: J
authors.lastname: Peng
authors.forename: Cuijie
authors.initials: C
authors.lastname: Feng
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.forename: Shaohua
authors.initials: S
authors.lastname: Chen
authors.forename: Yuanjian
authors.initials: Y
authors.lastname: Xu
authors.forename: Xingzu
authors.initials: X
authors.lastname: Wang
mesh_terms: D000085:Acetates / Q000378:metabolism; D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D058448:Biota; D016000:Cluster Analysis; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D058440:Denitrification; D008969:Molecular Sequence Data; D009566:Nitrates / Q000378:metabolism; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013440:Sulfides / Q000378:metabolism
chemical_list: D000085:Acetates; D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009566:Nitrates; D012336:RNA, Ribosomal, 16S; D013440:Sulfides