Surface water isolates of hemolytic and non-hemolytic Acinetobacter with multiple drug and heavy metal resistance ability

Acinetobacter in surface waters are a major concern because of their rapid development of resistance to a wide range of antimicrobials and their ability to persist in these waters for a very long time. Four surface water isolates of Acinetobacter having both multidrug- and multimetal-resistant ability were isolated and identified through biochemical tests and 16S rDNA sequencing. Based on these analyses, two hemolytic isolates were affiliated with Acinetobacter haemolyticus with an accession number of X81662. The other two non-hemolytic isolates were identified as Acinetobacter johnsonii and Acinetobacter calcoaceticus and affiliated with accession numbers of Z93440 and AJ888983, respectively. The antibiotic and heavy metal resistance profiles of the isolates were determined by using 26 antibiotics and 17 heavy metals. Acinetobacter isolates displayed resistance to β-lactams, cephalosporins, aminoglycosides, and sulfonamides. The hemolytic isolates were found to show resistance to higher numbers of heavy metals than the non-hemolytic ones. Due to a possible health risk of these pathogenic bacteria, a need exists for an accurate assessment of their acquired resistance to multiple drugs and metals.