title: Distribution of antibiotic resistance genes in glacier environments.
abstract: Antibiotic resistance genes are biologically transmitted from microorganism to microorganism in particular micro-environments where dense microbial communities are often exposed to an intensive use of antibiotics, such as intestinal microflora, and the soil microflora of agricultural fields. However, recent studies have detected antibiotic-resistant bacteria and/or antibiotic resistance genes in the natural environment geographically isolated from such areas. Here we sought to examine the prevalence of antibiotic resistance genes in 54 snow and ice samples collected from the Arctic, Antarctic, Central Asia, North and South America and Africa, to evaluate the level of these genes in environments supposedly not affected by anthropogenic factors. We observed a widespread distribution of antibiotic resistance genes in samples from various glaciers in Central Asia, North and South America, Greenland and Africa. In contrast, Antarctic glaciers were virtually free from these genes. Antibiotic resistance genes, of both clinical (i.e. aac(3), blaIMP) and agricultural (i.e. strA and tetW) origin, were detected. Our results show regional geographical distribution of antibiotic resistance genes, with the most plausible modes of transmission through airborne bacteria and migrating birds.
authors.affiliation: Transdisciplinary Research Integration Center, 4-3-13 Toranomon, Minato-ku, Tokyo 105-0001, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Segawa
authors.forename: Nozomu
authors.initials: N
authors.lastname: Takeuchi
authors.forename: Andres
authors.initials: A
authors.lastname: Rivera
authors.forename: Akinori
authors.initials: A
authors.lastname: Yamada
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Yoshimura
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Barcaza
authors.forename: Kunio
authors.initials: K
authors.lastname: Shinbori
authors.forename: Hideaki
authors.initials: H
authors.lastname: Motoyama
authors.forename: Shiro
authors.initials: S
authors.lastname: Kohshima
authors.forename: Kazunari
authors.initials: K
authors.lastname: Ushida
mesh_terms: D000349:Africa; D000864:Antarctic Regions; D001209:Asia, Central; D001419:Bacteria / Q000235:genetics* / Q000302:isolation & purification*; D004352:Drug Resistance, Microbial / Q000235:genetics*; D004777:Environment; D005798:Genes, Bacterial; D006116:Greenland; D046448:Ice Cover / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D009656:North America; D012988:Soil Microbiology; D013020:South America