As a widespread emerging contaminant,chloramphenicol(CAP)adversely impacts ecological communities in the water environment.Biological treatment is widely used for aquatic pollutant removal,and the performance of funct...As a widespread emerging contaminant,chloramphenicol(CAP)adversely impacts ecological communities in the water environment.Biological treatment is widely used for aquatic pollutant removal,and the performance of functional microbes determines its outcome.Herein,a consortium with a powerful CAPdegrading capacity was domesticated from activated sludge.As the common degradation products of CAP,4-nitrobenzoic acid(PNB)and 2,2-dichloroacetic acid(DCA)were also used as the sole substrates for long-term domestication.The successional pattern of the microbial community and critical functional genes through the 2.5-year domestication was revealed by metagenomic analysis.Sphingomonas,Caballeronia,and Cupriavidus became the most dominant populations in the CAP-,PNB-,and DCAdegrading consortia,respectively,and they were crucial degraders of PNB and DCA.Their collaboration contributed to the high mineralization rate of CAP.PNB was transformed into protocatechuic acid(PCA)and then mineralized through meta-cleavage and ortho-cleavage pathways.Crucial functional genes involved in CAP,PNB,and DCA metabolism,including CAP acetyltransferase,CAP oxidoreductase,haloacid dehalogenases,and protocatechuate dioxygenases,were significantly enriched in consortia.p H and carbon source had significant impacts on CAP biodegradation efficiency.The domesticated consortia and isolated strains are necessary microbial resources to enhance the bioremediation of CAP-,PNB-,or DCA-polluted environments.展开更多
基金funded by National Key Research and Development Program of China(2022YFE0103200)National Natural Science Foundation of China(22176107 and 22206107)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2019B151502034 and 2021A1515110772)China Postdoctoral Science Foundation(2021M691772)。
文摘As a widespread emerging contaminant,chloramphenicol(CAP)adversely impacts ecological communities in the water environment.Biological treatment is widely used for aquatic pollutant removal,and the performance of functional microbes determines its outcome.Herein,a consortium with a powerful CAPdegrading capacity was domesticated from activated sludge.As the common degradation products of CAP,4-nitrobenzoic acid(PNB)and 2,2-dichloroacetic acid(DCA)were also used as the sole substrates for long-term domestication.The successional pattern of the microbial community and critical functional genes through the 2.5-year domestication was revealed by metagenomic analysis.Sphingomonas,Caballeronia,and Cupriavidus became the most dominant populations in the CAP-,PNB-,and DCAdegrading consortia,respectively,and they were crucial degraders of PNB and DCA.Their collaboration contributed to the high mineralization rate of CAP.PNB was transformed into protocatechuic acid(PCA)and then mineralized through meta-cleavage and ortho-cleavage pathways.Crucial functional genes involved in CAP,PNB,and DCA metabolism,including CAP acetyltransferase,CAP oxidoreductase,haloacid dehalogenases,and protocatechuate dioxygenases,were significantly enriched in consortia.p H and carbon source had significant impacts on CAP biodegradation efficiency.The domesticated consortia and isolated strains are necessary microbial resources to enhance the bioremediation of CAP-,PNB-,or DCA-polluted environments.