SREL Reprint #1799

Spatial and temporal variability of antibiotic resistance in freshwater bacterial assemblages

Laura G. Leff1,2, J. Vaun McArthur1, and Lawrence J. Shimkets2 

1Savannah River Ecology Laboratory, Aiken, South Carolina, USA
2Department of Microbiology, University of Georgia, Athens, Georgia, USA 

Abstract: Spatial and temporal variability in antibiotic resistance was examined in bacterial assemblages from streams and ponds on the US Department of Energy's Savannah River Site (SRS) in South Carolina. Sites sampled have been impacted to varying degrees by contamination with organic compounds, heavy metals, and radioactive materials because of production of nuclear materials on the site. Antibiotic resistance in the culturable portion of the bacterial assemblage was determined from colony formation on media containing antibiotics. Eight antibiotics, chloramphenicol, cycloserine, kanamycin, neomycin, novobiocin, rifampicin, streptomycin, and tetracycline, were used at concentrations of 50 and 200 µg ml-1. Statistically significant differences in frequency of antibiotic resistance were observed among sites and among dates at a single site. Bacterial densities (total and culturable), dissolved organic carbon (DOC) concentration, and human impact also varied among sites but bore no overall relationship to resistance frequency. SRS operations did not have a detectable impact on antibiotic resistance.

Keywords: Antibiotic resistance; Streams; Carolina bays; Aquatic bacteria

SREL Reprint #1799

Leff, L.G., J.V. McArthur, and L.J. Shimkets. 1993. Spatial and temporal variability of antibiotic resistance in freshwater bacterial assemblages. FEMS Microbiology Ecology 13:135-144.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).