Detection and Characterization of a Multi-drug and Multi-metal Resistant Enterobacterium Pantoea sp. from Tannery Wastewater after Secondary Treatment Process

Abstract

In this study, an enterobacterium was isolated from treated tannery wastewater and characterized as gram-negative, rod shaped, motile, and lactose fermenting bacterium. Further, based on the 16S rRNA gene sequence analysis, the bacterium was identified as Pantoea sp. with accession number The antibiotic and heavy KJ576899. metal resistant property of isolated bacterium was investigated by the disk diffusion method on Muller-Hinton and nutrient agar medium amended with the increasing concentrations of various toxic metal ions, respectively. Results showed that the isolated bacterium was sensitive for amikacin, ampicillin, cefepime, cetriaxone, chloramphenicol, levofloxacin, meropenem, nalidixic acid, piperacillin and tobramycin, resistant for aztreonam, carbenicillin, cefotaxime, ceftazidime, ciprofloxacin, cotrimoxazole, imepenam, moxifloxacin, streptomycin and tetracycline, but intermediate for amoxicillin and gentamicin. In addition, the bacterium also showed the Minimum Inhibitory Concentration (MIC) values of 250, 500, 160, 190, 600, 700, 500, 380, 600 and 350 μg ml-1 forCu, Cr, Cd, Co, Zn, Fe, Ni, Pb, Mo and As, respectively with a plasmid DNA of 33.5 kb. This multi-drug and multi-metal resistant bacterium can be used as a potential agent for the bioremediation of metal contaminated sites.