Characterization of Heavy Metal and Antibiotic Resistant Bacteria Isolated from Aliaga Ship Dismantling Zone, Eastern Aegean Sea, Turkey

Abstract

In this study, it was aimed to determine the effects of ship dismantling zones on distribution of<br />heavy metal resistance and level of antibiotic resistance of bacterial isolates from Eastern Aegean Sea coast.<br />Thirteen isolates were identified by phylogenetic analysis using 16S rDNA sequences which indicated that the<br />isolates belonged to genus Bacillus. These strains were investigated in respect of the minimum inhibitory<br />concentrations (MICs) of heavy metals (Hg, Cu, Cd, Cr, Zn, Co, Ni, Pb and As) and susceptibility of some<br />antibiotics (ampicillin, tetracycline, chloramphenicol, vancomycin, gentamicin and tobramycin). The MICs of<br />heavy metals were different for each strain but the general order of resistance to the metals was found to be as Pb>As>Ni>Co>Cu>Zn>Cr>Cd>Hg and the toxic effects of these metals increased with increasing concentration. It can be concluded that all isolates were sensitive to Hg but were highly resistant to Pb, As and Ni. Additionally, it was found that the strains were resistant to gentamicin followed by tobramicin. The studies suggest that sediment bacteria in a ship dismantling area can be biological indicators of heavy metal contamination.