title: Association of antibiotic resistance in agricultural Escherichia coli isolates with attachment to quartz.
abstract: Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P < 0.0038) related to combined resistance to amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms.
authors.affiliation: Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Liu
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Soupir
authors.forename: Martha
authors.initials: M
authors.lastname: Zwonitzer
authors.forename: Bridgette
authors.initials: B
authors.lastname: Huss
authors.forename: Laura R
authors.initials: LR
authors.lastname: Jarboe
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001422:Bacterial Adhesion; D024881:Drug Resistance, Bacterial; D004783:Environmental Microbiology; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics; D005798:Genes, Bacterial; D020071:Interspersed Repetitive Sequences; D011791:Quartz; D013552:Swine / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D011791:Quartz