Anaerobic phenanthrene biodegradation with four kinds of electron acceptors enriched from the same mixed inoculum and exploration of metabolic pathways  

作　　者：Zuotao Zhang Chongyang Wang Jianzhong He Hui Wang 

机构地区：[1]State Key Joint Laboratory of Environment Simulation and Pollution Control,School of Environment,Tsinghua University,Beijing 100084,China [2]Miami College,Henan University,Kaifeng 475000,China [3]Department of Civil and Environmental Engineering,National University of Singapore,Singapore 117576,Singapore

出　　处：《Frontiers of Environmental Science & Engineering》2019年第5期175-186,共12页环境科学与工程前沿（英文）

基　　金：the National Natural Science Foundations of China(Grant Nos.41573065 and 41773082);the Key Project of Natural Science Foundation of China(No.21337001);the Mega-projects of Science Research for Water Environment Improvement(No.2017ZX07202002).

摘　　要：Polycyclic aromatic hydrocarbons (PAHs) are widespread and persistent contaminants worldwide, especially in environments devoid of molecular oxygen. For lack of molecular oxygen, researchers enhanced anaerobic zones PAHs biodegradation by adding sulfate, bicarbonate, nitrate, and iron. However, microbial community reports of them were limited, and information of metabolites was poor except two-ring PAH, naphthalene. Here, we reported on four phenanthrene-degrading enrichment cultures with sulfate, bicarbonate, nitrate, and iron as electron acceptors from the same initial inoculum. The high-to-low order of the anaerobic phenanthrene biodegradation rate was the nitrate-reducing conditions>sulfate-reducing conditions>methanogenic conditions>iron-reducing conditions. The dominant bacteria populations were Desulfobacteraceae, Anaerolinaceae, and Thermodesulfobiaceae under sulfate-reducing conditions;Moraxellaceae, Clostridiaceae, and Comamonadaceae under methanogenic conditions;Rhodobacteraceae, Planococcaceae, and Xanthomonadaceae under nitrate-reducing conditions;and Geobacteraceae, Carnobacteriaceae, and Anaerolinaceae under iron-reducing conditions, respectively. Principal component analysis (PCA) indicated that bacteria populations of longtime enriched cultures with four electron acceptors all obtained significant changes from original inoculum, and bacterial communities were similar under nitrate-reducing and iron-reducing conditions. Archaea accounted for a high percentage under iron-reducing and methanogenic conditions, and Methanosarcinaceae and Methanobacteriaceae, as well as Methanobacteriaceae, were the dominant archaea populations under iron-reducing and methanogenic conditions. The key steps of phenanthrene biodegradation under four reducing conditions were carboxylation, further ring system reduction, and ring cleavage.

关 键 词：PHENANTHRENE ANAEROBIC BIODEGRADATION Bacterial POPULATIONS ARCHAEA POPULATIONS METABOLIC pathway 

分 类 号：S15[农业科学—土壤学]