title: Structural and functional response of the soil bacterial community to application of manure from difloxacin-treated pigs.
abstract: Difloxacin (DIF) belongs to the class of fluoroquinolone antibiotics that have been intensively used for the treatment of bacterial infections in veterinary and human medicine. The aim of this field study was to compare the effect of manure from DIF-treated pigs and untreated pigs on the bacterial community structure and resistance gene abundance in bulk soil and rhizosphere of maize. A significant effect of DIF manure on the bacterial community composition in bulk soil was revealed by denaturing gradient gel electrophoresis (DGGE) of bacterial 16S rRNA gene fragments amplified from total community DNA. In few samples, quinolone resistance genes qnrB and qnrS1/qnrS2 were detected by PCR and subsequent hybridization, while qnrA was not detected. Quantitative PCR revealed an increased abundance of the integrase gene intI1 of class I integrons and sulfonamide resistance genes sul1 and sul2 in DIF manure-treated bulk soil and rhizosphere, relative to 16S rRNA genes, while traN genes specific for LowGC-type plasmids were increased only in bulk soil. Principal component analysis of DGGE profiles suggested a manure effect in soil until day 28, but samples of days 71 and 140 were found close to untreated soil, indicating resilience of soil community compositions from disturbances by manure.
authors: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, Braunschweig, Germany.
authors: Sven
authors: S
authors: Jechalke
authors: Andreas
authors: A
authors: Focks
authors: Ingrid
authors: I
authors: Rosendahl
authors: Joost
authors: J
authors: Groeneweg
authors: Jan
authors: J
authors: Siemens
authors: Holger
authors: H
authors: Heuer
authors: Kornelia
authors: K
authors: Smalla
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D001426:Bacterial Proteins / Q000235:genetics; D002939:Ciprofloxacin / Q000031:analogs & derivatives* / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D032023:Integrons / Q000187:drug effects; D008372:Manure; D058441:Rhizosphere; D012988:Soil Microbiology; D034421:Sus scrofa; D013552:Swine; D003313:Zea mays / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D008372:Manure; D002939:Ciprofloxacin; C047225:difloxacin
keywords: DGGE; Difloxacin; manure; resistance; rhizosphere; soil