title: Class 1 Integrons and the Antiseptic Resistance Gene (qacEΔ1) in Municipal and Swine Slaughterhouse Wastewater Treatment Plants and Wastewater-Associated Methicillin-Resistant Staphylococcus aureus.
abstract: Class 1 integrons are mobile gene elements (MGEs) containing qacEΔ1 that are resistant to quaternary ammonium compound (QAC) disinfectants. This study compared the abundances of class 1 integrons and antiseptic resistance genes in municipal (M) and swine slaughterhouse (S) wastewater treatment plants (WWTPs) and investigated the presence of class 1 integrons and antiseptic resistance genes in methicillin-resistant Staphylococcus aureus (MRSA) isolated from wastewater samples. The abundances of intI1 and qacEΔ1 genes in 96 wastewater samples were quantified using real-time quantitative polymerase chain reaction (real-time qPCR), and 113 MRSA isolates recovered from the wastewater samples were detected class 1 integrons and linked antiseptic resistance genes (qacEΔ1), and minimum inhibitory concentrations (MICs) for QAC antiseptics. The intI1 and qacEΔ1 genes were detected in all the wastewater samples, and they were more abundant in S-WWTP samples than in M-WWTP samples. A higher percentage of MRSA isolates carried qacEΔ1 in MRSA from swine wastewater samples (62.8%) than in municipal MRSA (3.7%). All the MRSA isolates showed high MICs for antiseptic agents. This study provides important evidence regarding the abundances of intI1 and qacEΔ1 genes in municipal and swine slaughterhouse wastewater, and antiseptic-resistant MRSA strains were detected in swine slaughterhouse wastewater.
authors.affiliation: School of Veterinary Medicine, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei 106, Taiwan. d99629002@ntu.edu.tw.|Biodiversity Research Center, Academia Sinica, 128 Academia Road, Section 2, Taipei 115, Taiwan. d99629002@ntu.edu.tw.
authors.forename: Min Tao
authors.initials: MT
authors.lastname: Wan
authors.affiliation: School of Veterinary Medicine, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei 106, Taiwan. chouchin@ntu.edu.tw.
authors.forename: Chin Cheng
authors.initials: CC
authors.lastname: Chou
mesh_terms: D000003:Abattoirs; D000818:Animals; D000891:Anti-Infective Agents, Local; D001426:Bacterial Proteins / Q000235:genetics; D004202:Disinfectants; D019426:Integrases / Q000032:analysis; D032023:Integrons; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D060888:Real-Time Polymerase Chain Reaction; D013552:Swine; D062065:Wastewater / Q000737:chemistry* / Q000382:microbiology
chemical_list: D000891:Anti-Infective Agents, Local; D001426:Bacterial Proteins; D004202:Disinfectants; D019426:Integrases; D062065:Wastewater; C115006:integron integrase IntI1
keywords: class 1 integrons and antiseptic resistance genes; methicillin-resistant Staphylococcus aureus; wastewater