title: Triclosan Resistome from Metagenome Reveals Diverse Enoyl Acyl Carrier Protein Reductases and Selective Enrichment of Triclosan Resistance Genes.
abstract: Triclosan (TCS) is a widely used antimicrobial agent and TCS resistance is considered to have evolved in diverse organisms with extensive use of TCS, but distribution of TCS resistance has not been well characterized. Functional screening of the soil metagenome in this study has revealed that a variety of target enoyl acyl carrier protein reductases (ENR) homologues are responsible for the majority of TCS resistance. Diverse ENRs similar to 7-α-hydroxysteroid dehydrogenase (7-α-HSDH), FabG, or the unusual YX7K-type ENR conferred extreme tolerance to TCS. The TCS-refractory 7-α HSDH-like ENR and the TCS-resistant YX7K-type ENR seem to be prevalent in human pathogenic bacteria, suggesting that a selective enrichment occurred in pathogenic bacteria in soil. Additionally, resistance to multiple antibiotics was found to be mediated by antibiotic resistance genes that co-localize with TCS resistance determinants. Further comparative analysis of ENRs from 13 different environments has revealed a huge diversity of both prototypic and metagenomic TCS-resistant ENRs, in addition to a selective enrichment of TCS-resistant specific ENRs in presumably TCS-contaminated environments with reduced ENR diversity. Our results suggest that long-term extensive use of TCS can lead to the selective emergence of TCS-resistant bacterial pathogens, possibly with additional resistance to multiple antibiotics, in natural environments.
authors: Department of Applied Biology, Dong-A University, Busan 604-714, Republic of Korea.
authors: Raees
authors: R
authors: Khan
authors: Department of Applied Biology, Dong-A University, Busan 604-714, Republic of Korea.
authors: Hyun Gi
authors: HG
authors: Kong
authors: Department of Applied Bioscience, Dong-A University, Busan 604-714, Republic of Korea.
authors: Yong-Hoon
authors: YH
authors: Jung
authors: Department of Applied Bioscience, Dong-A University, Busan 604-714, Republic of Korea.
authors: Jinhee
authors: J
authors: Choi
authors: Department of Applied Bioscience, Dong-A University, Busan 604-714, Republic of Korea.
authors: Kwang-Yeol
authors: KY
authors: Baek
authors: Department of Applied Biology, Dong-A University, Busan 604-714, Republic of Korea.
authors: Eul Chul
authors: EC
authors: Hwang
authors: Department of Applied Biology, Dong-A University, Busan 604-714, Republic of Korea.|Department of Applied Bioscience, Dong-A University, Busan 604-714, Republic of Korea.
authors: Seon-Woo
authors: SW
authors: Lee
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics; D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000472:pathogenicity; D004352:Drug Resistance, Microbial / Q000187:drug effects / Q000235:genetics*; D050753:Enoyl-(Acyl-Carrier-Protein) Reductase (NADH) / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D006913:Hydroxysteroid Dehydrogenases / Q000235:genetics; D054892:Metagenome / Q000187:drug effects / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D014260:Triclosan / Q000627:therapeutic use
chemical_list: D014260:Triclosan; D000429:Alcohol Oxidoreductases; D006913:Hydroxysteroid Dehydrogenases; C025376:7 alpha-hydroxysteroid dehydrogenase; C023744:acetoacetyl-CoA reductase; D050753:Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)