CONCENTRATION OF HEAVY METALS AND INVESTIGATION OF BACTERIAL TOXIC METAL RESISTANCE IN COASTAL CITY SEDIMENTS (EASTERN AEGEAN SEA)

Izmir is located on the Eastern Coast of the Aegean Sea in Turkey. In present study, it was aimed to determine the toxic metal resistance of bacterial isolates from coastal city sediments. Twenty-six isolates (Bacillus, Marinibacillus, Halobacillus) were identified and these strains were investigated in respect of the minimum inhibitory concentrations of metals, susceptibility of some antibiotics (Ampicillin, Tetracycline, Chloramphenicol, Tobramycin). The MICs of metals were different for each strain but the general order of resistance to the metals was found to be as Ni>Pb>Cu>Cr>Cd>Hg and the toxic effects of these metals increased with increasing concentration. Bacterial isolates were highly resistant to Ni (13 mM), Pb (6 mM). Additionally, it was found that the strains were resistant to Ampicillin. The highest concentrations of metals were found in the sediments of the inner part of the Bay, which is intensely industrialized compared to the middle and outer parts of the Bay. This study and several other studies suggest that sediment bacteria in an area polluted with heavy metal can be biological indicators.