Microbial population dynamics in deltaic aquatic ecosystems - case study on Sfantu Gheorghe Branc

The aquatic ecosystems – a perfect environment to propagate the characters of pathogenicity and virulence of the microorganisms, could be reservoirs of antibiotic resistance genes. During January – June 2013, a program to investigate bacteriological water quality of St. Gheorghe branch has been created. The investigations were carried out systematically, by establishing 11 locations with anthropogenic potential risks that could influence the quality of aquatic ecosystems. The surface water and sediments samples were monthly collected and the bacteriological indicators with their antibiotic resistance profile were quantified and analyzed. The Enterobacteriaceae and Pseudomonas sp. strains with antibiotic resistance profile were identified and they were subjected to PCR technique to identify the genes encoding these resistance mechanisms. The natural resistance mechanisms to antibiotics were identified, but there was amplified a tem gene which encode for resistance to β-lactams.