Xueqi Chen, Zhiling Li, Zimeng Zhang, Jun Nan, Guanshu Zhao, Shih-Hsin Ho, Bin Liang, Aijie Wang
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引用次数: 0
Abstract
Organohalide-respiring bacteria (OHRB) play a key role in facilitating the detoxification of halogenated organics, but their slow growth and harsh growth conditions often limit their application in field remediation. In this study, we investigated the metabolic performance and organohalide respiration process of a non-obligate OHRB, Pseudomonas sp. CP-1, demonstrating favorable anaerobic reductive dechlorination ability of 2,4,6-trichlorophenol to 4-chlorophenol with a removal rate constant (k) of 0.46 d-1. Due to its facultative anaerobic nature, strain CP-1 exhibited unique metabolic properties. In aerobic conditions, strain CP-1 preferentially utilized oxygen for rapid proliferation, and anaerobic reductive dechlorination was initiated once the oxygen was depleted. The aerobic proliferation facilitated the subsequent reductive dechlorination process. Through multi-tool analysis, a modified tricarboxylic acid cycle was proposed to be linked to organohalide respiration when acetate served as the sole carbon source. A predictive model for the electron transport chain (ETC) for reductive dechlorination was constructed, with complex Ⅰ, complex Ⅱ, ubiquinone, complex Fix (flavoprotein), and reductive dehalogenase (RDase) as the major components. A specific RDase facilitating reductive dechlorination was identified. It shared a 64.35% amino acid similarity with biochemically characterized RDases and was designated CprA-2. Its ortho-dechlorination catalytic process was proposed through molecular docking. The discovery of highly adaptable Pseudomonas with favorable dechlorination activity and the elucidation of its metabolic properties provide valuable insights into the understanding of non-obligate OHRBs and their application regulation.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.