title: Development and application of a novel and effective screening method for aerobic denitrifying bacteria.
abstract: Herein we describe a novel and effective screening method for aerobic denitrifying bacteria. For this procedure, we utilized KCN to inhibit the electron transference from Cytaa3 to oxygen in the bacteria respiratory chain. We employed a 3-h aeration operation cycle and intermittent rotations. The resultant bacterial suspensions were plated on a KCN-screening medium and incubated aerobically. Single colonies were selected and incubated in an aerobic culture medium. Culture nitrate and nitrite levels were determined over time, and ultimately four bacterial strains that performed denitrifying under aerobic conditions were identified by this method. Of these, strain Y2-1-1 demonstrated the best aerobic denitrifying ability. In a 5-day test, the NO3--N of the aerobic culture medium was reduced from 282.0+/-8.3 mg L(-1) to 149.2+/-17.1 mg L(-1), with little nitrite or N2O production. The morphological, physiological and biochemical characteristics and the 16S rRNA gene sequence homology comparison data for this strain were consistent with the classification of the genus Pseudomonas. We named this strain Pseudomonas sp. Y2-1-1.
authors.affiliation: Department of Environment and Health, Tianjin Institute of Environment and Health, Tianjin, China.
authors.forename: Qin-Xin
authors.initials: QX
authors.lastname: Kong
authors.forename: Xin-Wei
authors.initials: XW
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Jin
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Shen
authors.forename: Jun-Wen
authors.initials: JW
authors.lastname: Li
mesh_terms: D000332:Aerobiosis; D015373:Bacterial Typing Techniques; D003470:Culture Media; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D008969:Molecular Sequence Data; D050901:Nitrate Reductase / Q000235:genetics*; D009566:Nitrates / Q000378:metabolism*; D009573:Nitrites / Q000378:metabolism; D010101:Oxygen Consumption; D010802:Phylogeny; D011190:Potassium Cyanide / Q000494:pharmacology; D011549:Pseudomonas / Q000145:classification* / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009566:Nitrates; D009573:Nitrites; D012336:RNA, Ribosomal, 16S; D050901:Nitrate Reductase; D011190:Potassium Cyanide