A statistical approach to determine co-existence of heavy metal and antibiotic resistance in environmental isolates of Khewra salt range, Pakistan

Wastewater treatment plant is a potential reservoir contributing to the evolution and spread of heavy metal and antibiotic resistant bacteria. The pollutants such as biocides, antibiotics, heavy metals are to be feared for as they have been known to evoke resistance in microorganisms in such polluted environment. The aim of this study was to the isolate bacteria from the treated wastewater and assess the resistance pattern of the isolates against antibiotics and heavy metals. Grab sampling was performed from April to June 2017, from the treated effluent from the secondary treatment plant. To assess the resistance pattern for antibiotic(s) and heavy metal(s), antibiotic susceptibility test and minimum inhibitory concentration by cup well method were performed respectively. Staphylococcus aureus, Enterococcus faecalis, Citrobacter freundii, Escherichia coli, Enterobacter aerogenes, Proteus mirabilis, P. vulgaris, Salmonella Typhi, Pseudomonas aeruginosa were isolated. Multi drug and heavy metal resistant isolates were screened. Fisher’s exact test revealed that there is a significant association (p< 0.001) between antibiotic resistance pattern and resistance patterns at dilution of 2500 g/L (25%). Cramer’s V test revealed that the effect size of antibiotic resistance pattern and heavy metal resistance pattern at dilution 2500 g/L is medium. P. aeruginosa was able to resist the metal concentration up to 10000 g/L (100%) dilution of Fe++. Heavy metal resistant bacteria can be safely used to lower chemical concentration in the environment once their harmful genes are edited, knocked etc. so that risks of evoking antibiotic resistance could be minimized.

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Plasmid mediated transfer of antibiotic resistance and heavy metal tolerance in thermotolerant water borne coliforms

African Journal of Microbiology Research ◽

10.5897/ajmr12.1563 ◽

2013 ◽

Vol 7 (2) ◽

pp. 130-136 ◽

Cited By ~ 4

Author(s):

Tewari Suman ◽

W Ramteke Pramod ◽

Tripathi Manikant ◽

Kumar Shailendra ◽

Kumar Garg Satyendra

Keyword(s):

Heavy Metal ◽

Antibiotic Resistance ◽

Metal Tolerance ◽

Heavy Metal Tolerance ◽

Water Borne

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Prevalence And Characterization Of Plasmid-Mediated Quinolone Resistance In Various Aquatic Sources

10.32920/ryerson.14652291.v1 ◽

2021 ◽

Author(s):

Farhan Yusuf ◽

Kimberley Gilbride

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Quinolone Resistance ◽

Resistant Bacteria ◽

Rrna Gene ◽

Environmental Isolates ◽

Topoisomerase Iv ◽

Phenotypic Resistance ◽

Ciprofloxacin Resistance

Bacterial isolates found in aquatic ecosystems often carry antibiotic resistance genes (ARGs). These ARGs are often found on plasmids and transposons, which allows them to be proliferate throughout bacterial communities via horizontal gene transfer (HGT) causing dissemination of multidrug resistance. The increase in antibiotic resistance has raised concerns about the ability to continue to use these drugs to fight infectious diseases. Novel synthetic antibiotics like ciprofloxacin that are not naturally found in the environment were developed to prevent resistances. However, ciprofloxacin resistance has occurred through chromosomal gene mutations of type 2 topoisomerases or by the acquisition of plasmid-mediated quinolone resistances (PMQR). A particular PMQR, qnr genes, encoding for pentapeptide repeat proteins that confer low levels of quinolone resistance and protect DNA gyrase and topoisomerase IV from antibacterial activity. These qnr genes have been identified globally in both clinical and environmental isolates. The aim of this study was to determine the prevalence of ciprofloxacin-resistant bacteria in aquatic environments in the Greater Toronto Area and the potential dissemination of ciprofloxacin resistance. With the selective pressure of ciprofloxacin, we hypothesize that ciprofloxacin-resistant bacteria (CipR) in the environment may carry PMQR mechanisms while the sensitive population (CipS) would not carry PMQR genes. Isolates were tested for resistance to an additional 12 different antibiotics and identified using Sanger sequencing PCR products of the 16S rRNA gene. To determine which genes are responsible for ciprofloxacin resistance, multiplex PCR of associated qnr genes, qnrA, qnrB, and qnrS, was carried out on 202 environmental isolates. Our data demonstrate a similar prevalence of qnr genes was found in CipR (19%) and CipS (14%) populations suggesting that the presence of these genes was not necessarily correlated with the phenotypic resistance to the antibiotic. Furthermore, ciprofloxacinresistant bacteria were found in all locations at similar frequencies suggesting that resistance genes are widespread and could possibly arise through HGT events. Overall, determining the underlying cause and prevalence of ciprofloxacin resistance could help re-establish the effectiveness of these antimicrobial compounds.

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