title: Response of bacterial isolates from Antarctic shallow sediments towards heavy metals, antibiotics and polychlorinated biphenyls.
abstract: The response of bacterial isolates from Antarctic sediments to polychlorinated biphenyls (Aroclor 1242 mixture), heavy metal salts (cadmium, copper, mercury and zinc) and antibiotics (ampicillin, chloramphenicol, kanamycin and streptomycin) was investigated. Overall, the ability to growth in the presence of Aroclor 1242 as a sole carbon source was observed for 22 isolates that mainly belonged to Psychrobacter spp. Tolerance to the heavy metals assayed in this study was in the order of Cd > Cu > Zn > Hg and appeared to be strictly related to the metal concentrations, as determined during previous chemical surveys in the same area. With regards to antibiotic assays, the response of the isolates to the tested antibiotics ranged from complete resistance to total susceptibility. In particular, resistances to ampicillin and chloramphenicol were very pronounced in the majority of isolates. Our isolates differently responded to the presence of toxic compounds primarily based on their phylogenetic affiliation and secondarily at strain level. Moreover, the high incidence of resistance either to metal or antibiotics, in addition to the capability to grow on PCBs, confirm that bacteria are able to cope and/or adapt to the occurrence pollutants even in low human-impacted environments.
authors.affiliation: Department of Biological and Environmental Sciences, University of Messina, Messina, Italy. alogiudice@unime.it
authors.forename: Angelina
authors.initials: A
authors.lastname: Lo Giudice
authors.forename: Patrizia
authors.initials: P
authors.lastname: Casella
authors.forename: Vivia
authors.initials: V
authors.lastname: Bruni
authors.forename: Luigi
authors.initials: L
authors.lastname: Michaud
mesh_terms: D000222:Adaptation, Physiological; D000667:Ampicillin / Q000633:toxicity; D000864:Antarctic Regions; D000900:Anti-Bacterial Agents / Q000633:toxicity*; D001140:Aroclors / Q000633:toxicity*; D001419:Bacteria / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D019256:Cadmium Chloride / Q000633:toxicity; D002701:Chloramphenicol / Q000633:toxicity; D002712:Chlorides / Q000633:toxicity; D003300:Copper / Q000633:toxicity; D004269:DNA, Bacterial / Q000032:analysis; D024901:Drug Resistance, Multiple, Bacterial; D019015:Geologic Sediments / Q000382:microbiology*; D007612:Kanamycin / Q000633:toxicity; D019216:Metals, Heavy / Q000633:toxicity*; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D021521:Ribotyping; D013307:Streptomycin / Q000633:toxicity; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D017967:Zinc Compounds / Q000633:toxicity
chemical_list: D000900:Anti-Bacterial Agents; D001140:Aroclors; D002712:Chlorides; D004269:DNA, Bacterial; D019216:Metals, Heavy; D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D017967:Zinc Compounds; C027423:aroclor 1242; D007612:Kanamycin; D002701:Chloramphenicol; D003300:Copper; D000667:Ampicillin; C016837:zinc chloride; D019256:Cadmium Chloride; C029892:cupric chloride; D013307:Streptomycin