title: The characteristics of a novel heterotrophic nitrification-aerobic denitrification bacterium, Bacillus methylotrophicus strain L7.
abstract: Bacillus methylotrophicus strain L7, exhibited efficient heterotrophic nitrification-aerobic denitrification ability, with maximum NH(4)(+)-N and NO(2)(-)-N removal rate of 51.58 mg/L/d and 5.81 mg/L/d, respectively. Strain L7 showed different gaseous emitting patterns from those strains ever described. When (15)NH(4)Cl, or Na(15)NO(2), or K(15)NO(3) was used, results of GC-MS indicated that N(2)O was emitted as the intermediate of heterotrophic nitrification or aerobic denitrification, while GC-IRMS results showed that N(2) was produced as end product when nitrite was used. Single factor experiments suggested that the optimal conditions for heterotrophic nitrification were sodium succinate as carbon source, C/N 6, pH 7-8, 0 g/L NaCl, 37 °C and a wide range of NH(4)(+)-N from 80 to 1000 mg/L. Orthogonal tests showed that the optimal conditions for aerobic denitrification were C/N 20, pH 7-8, 10 g/L NaCl and DO 4.82 mg/L (shaking speed 50 r/min) when nitrite was served as substrate.
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Qing-Ling
authors.initials: QL
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Guo-Min
authors.initials: GM
authors.lastname: Ai
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Miao
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Zheng
authors.forename: Zhi-Pei
authors.initials: ZP
authors.lastname: Liu
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D001407:Bacillus / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D058440:Denitrification / Q000502:physiology*; D008401:Gas Chromatography-Mass Spectrometry; D058465:Nitrification / Q000502:physiology*; D009573:Nitrites / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013056:Spectrophotometry, Ultraviolet; D013386:Succinates; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods*
chemical_list: D017931:DNA Primers; D009573:Nitrites; D012336:RNA, Ribosomal, 16S; D013386:Succinates; D000641:Ammonia