title: Fate of tetracycline, sulfonamide and fluoroquinolone resistance genes and the changes in bacterial diversity during composting of swine manure.
abstract: This study monitored the abundance of antibiotic resistant genes (ARGs) and the bacterial diversity during composting of swine manure spiked with chlortetracycline, sulfadiazine and ciprofloxacin at two different levels and a control without antibiotics. Resistance genes of tetracycline (tetQ, tetW, tetC, tetG, tetZ and tetY), sulfonamide (sul1, sul2, dfrA1 and dfrA7) and fluoroquinolone (gyrA and parC) represented 0.02-1.91%, 0.67-10.28% and 0.00005-0.0002%, respectively, of the total 16S rDNA copies in the initial composting mass. After 28-42 days of composting, these ARGs, except parC, were undetectable in the composting mass indicating that composting is a potential method of manure management. Polymerase chain reaction-denaturing gradient gel electrophoresis analysis of bacterial 16S rDNA of the composting mass indicated that the addition of antibiotics up to 100, 20 and 20mg/kg of chlortetracycline, sulfadiazine and ciprofloxacin, respectively, elicited only a transient perturbation and the bacterial diversity was restored in due course of composting.
authors.affiliation: Sino-Forest Applied Research Centre for Pearl River Delta Environment, Hong Kong Baptist University, Kowloon Tong, Hong Kong.
authors.forename: Ammaiyappan
authors.initials: A
authors.lastname: Selvam
authors.forename: Delin
authors.initials: D
authors.lastname: Xu
authors.forename: Zhenyong
authors.initials: Z
authors.lastname: Zhao
authors.forename: Jonathan W C
authors.initials: JW
authors.lastname: Wong
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001673:Biodegradation, Environmental / Q000187:drug effects; D044822:Biodiversity; D002939:Ciprofloxacin / Q000494:pharmacology; D058645:Denaturing Gradient Gel Electrophoresis; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D024841:Fluoroquinolones / Q000494:pharmacology; D005798:Genes, Bacterial / Q000235:genetics*; D008372:Manure / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology; D013411:Sulfadiazine / Q000494:pharmacology; D013449:Sulfonamides / Q000494:pharmacology; D013552:Swine; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D008372:Manure; D012336:RNA, Ribosomal, 16S; D012987:Soil; D013449:Sulfonamides; D013411:Sulfadiazine; D002939:Ciprofloxacin; D013752:Tetracycline