GCRC Project Summary |
From Animal Farms to Oyster Beds: Tetracycline Resistance Genes in the Altamaha River Watershed and Estuary
PIs: Andrei L. Barkovskii, C. Coleman, A. Bozdag, G. Kohlhagen, L. Pierce, C. Green, Georgia College and State University
Support:
Coastal Incentive Grant
Timeframe: 2007
- 2008
Project Objectives:
The usability of tetracycline resistance genes and the genes indicating the presence of integrons as indicators and tracers of anthropogenic contamination in oyster beds was evaluated. The presence, distribution and concentrations of these genes were monitored in the Altamaha River estuary. Samples were collected every four months, community DNA was extracted, and 16 tetracycline resistance (tet) genes along with three genes encoding integrase (intl) 1, 2 and 3 were targeted in the DNA.
Results to Date :
- Overall, we observed a wide array of tet genes. In the meantime, the presence of intl genes were not detected in the estuary.
- Distribution of tet genes between water column, sediments, and oysters varied between the stations and seasonally.
- Among all of the tet genes targeted, tet (D) and tet (G) were most indicative for the water column and sediment contamination. Their concentrations widely varied in the 100 - 1016 range between the stations and sampling events indicating that these genes are suitable for monitoring water quality in oyster beds. Both of these genes were also observed in oysters.
- We concluded that the tet gene profiles are reflective of fecal contamination of the estuary. Their profiles and abundance in all three matrices (the water column, sediments, and oysters) are indicative of the degree of fecal contamination in oyster beds and its likely origin.
Related Project:
Geochemical
and Microbial Signatures for Anthropogenic Disturbance of Coastal Environments
Andrei
L. Barkovskii (Georgia College and State Univ.), Dave S. Bachoon (Georgia
College and State Univ.), and Johannes E. Leisen (Georgia Inst. of Tech.)