title: Food commensal microbes as a potentially important avenue in transmitting antibiotic resistance genes.
abstract: The rapid emergence of antibiotic-resistant (ART) pathogens is a major threat to public health. While the surfacing of ART food-borne pathogens is alarming, the magnitude of the antibiotic resistance (AR) gene pool in food-borne commensal microbes is yet to be revealed. Incidence of ART commensals in selected retail food products was examined in this study. The presence of 10(2)-10(7) CFU of ART bacteria per gram of foods in many samples, particularly in ready-to-eat, 'healthy' food items, indicates that the ART bacteria are abundant in the food chain. AR-encoding genes were detected in ART isolates, and Streptococcus thermophilus was found to be a major host for AR genes in cheese microbiota. Lactococcus lactis and Leuconostoc sp. isolates were also found carrying AR genes. The data indicate that food could be an important avenue for ART bacterial evolution and dissemination. AR-encoding plasmids from several food-borne commensals were transmitted to Streptococcus mutans via natural gene transformation under laboratory conditions, suggesting the possible transfer of AR genes from food commensals to human residential bacteria via horizontal gene transfer.
authors.affiliation: Department of Food Science and Technology, The Ohio State University, Columbus, OH, USA. wang.707@osu.edu
authors.forename: Hua H
authors.initials: HH
authors.lastname: Wang
authors.forename: Michele
authors.initials: M
authors.lastname: Manuzon
authors.forename: Mark
authors.initials: M
authors.lastname: Lehman
authors.forename: Kai
authors.initials: K
authors.lastname: Wan
authors.forename: Hongliang
authors.initials: H
authors.lastname: Luo
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Wittum
authors.forename: Ahmed
authors.initials: A
authors.lastname: Yousef
authors.forename: Lauren O
authors.initials: LO
authors.lastname: Bakaletz
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000235:genetics* / Q000254:growth & development; D001426:Bacterial Proteins / Q000235:genetics*; D002611:Cheese / Q000382:microbiology; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005516:Food Microbiology; D022761:Gene Transfer, Horizontal; D006095:Gram-Positive Cocci / Q000187:drug effects / Q000235:genetics; D006801:Humans; D014169:Transformation, Bacterial
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins