title: Relative contributions of archaea and bacteria to microbial ammonia oxidation differ under different conditions during agricultural waste composting.
abstract: The aim of this study was to compare the relative contribution of ammonia-oxidizing archaea (AOA) and bacteria (AOB) to nitrification during agricultural waste composting. The AOA and AOB amoA gene abundance and composition were determined by quantitative PCR and denaturing gradient gel electrophoresis (DGGE), respectively. The results showed that the archaeal amoA gene was abundant throughout the composting process, while the bacterial amoA gene abundance decreased to undetectable level during the thermophilic and cooling stages. DGGE showed more diverse archaeal amoA gene composition when the potential ammonia oxidation (PAO) rate reached peak values. A significant positive relationship was observed between the PAO rate and the archaeal amoA gene abundance (R²=0.554; P<0.001), indicating that archaea dominated ammonia oxidation during the thermophilic and cooling stages. Bacteria were also related to ammonia oxidation activity (R²=0.503; P=0.03) especially during the mesophilic and maturation stages.
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, China. zgming@hnu.cn
authors.forename: Guangming
authors.initials: G
authors.lastname: Zeng
authors.forename: Jiachao
authors.initials: J
authors.lastname: Zhang
authors.forename: Yaoning
authors.initials: Y
authors.lastname: Chen
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yu
authors.forename: Man
authors.initials: M
authors.lastname: Yu
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Liu
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.forename: Lunhui
authors.initials: L
authors.lastname: Lu
authors.forename: Chunxiao
authors.initials: C
authors.lastname: Hu
mesh_terms: D000383:Agriculture / Q000379:methods*; D000641:Ammonia / Q000378:metabolism*; D001105:Archaea / Q000235:genetics / Q000378:metabolism*; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D058645:Denaturing Gradient Gel Electrophoresis; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012987:Soil; D014866:Waste Products
chemical_list: D012987:Soil; D014866:Waste Products; D000641:Ammonia; D010088:Oxidoreductases; C045582:ammonia monooxygenase