Vol. 7 No. 01 (2026)
Articles

Investigating Escherichia coli Resistance to Antibiotics and Heavy Metals

PDF
  • Diana Noor Al Din Mustafa,
  • Hiba Khalid Mahmood
Diana Noor Al Din Mustafa Department of Environmental Technologies, College of Environmental Science, University of Mosul, Mosul, Iraq
Hiba Khalid Mahmood Department of Biology, College of Science, University of Mosul, Mosul, Iraq

Published 2026-04-10

Keywords

  • Plasmid Curing,
  • Antimicrobial Resistance,
  • Heavy Metal Resistance,
  • Escherichia coli

Copyright (c) 2026 Diana Noor Al Din Mustafa, Hiba Khalid Mahmood

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

How to Cite

Investigating Escherichia coli Resistance to Antibiotics and Heavy Metals. (2026). Journal of Life and Bio-Sciences Research, 7(01), 16-22. https://doi.org/10.38094/jlbsr701178

Abstract

Bacterial resistance to antibiotics and heavy metals is an increasing ecological and public health risk. The genes responsible for the resistance are mainly carried on resistant plasmids; the elimination of these plasmids is carried out by curing using physical agents like low pH levels and elevated temperature. In this study, four stool isolates of Escherichia coli were obtained from Ibn-Sina Hospital in Mosul city, Iraq. The isolates were diagnosed using appropriate biochemical tests and tested for their resistance against five antibiotics: Ampicillin (Amp), Tetracycline (Tc), Erythromycin (Er), Nalidixic acid (Nal), and Chloramphenicol (Cm); and three heavy metals: Mercury chloride (HgCl2), Cobalt chloride (CoCl2), and Copper chloride (CuCl2). Results showed that all isolates were 100% resistant to (Nal) and (CuCl2), and (75%) for (Amp) and (Cocl2), while (50%) of the isolates were resistant to Tc and (25%) for Er and Cm; however, all isolates were sensitive to (HgCl2). MIC was conducted to examine the ability of bacteria to tolerate heavy metal concentrations, and we found that the MIC for Cobalt was 1000µg/ml and 1700 µg/ml for copper. Using low pH (pH5) as a curing agent showed that the resistance for Tc and Nal was lost in 60-64% and 36-68% of the isolates, respectively, while resistance to cobalt was lost in 40-52% of the isolates. These results suggest that genes responsible for the resistance of Tc, Nal, and Cobalt are probably located on the plasmids; while the resistance of Amp, Er, Cm, and Copper was not affected, which may suggest that they are chromosomally encoded. Using elevated temperature (46°C) as a curing agent showed higher rates for curing of Tc (94-96%), Nal (72-92%), and Cobalt (88-96%), which supports the results for gene location obtained from curing with low pH.

PDF

References

  1. Alav, I., Pordelkhaki, P., de Resende, P.E., Partington, H., Gibbons, S., Lord, R. M., Buckner, M.C. (2024). Cobalt complexes modulate plasmid conjugation in Escherichia coli and Klebsiella pneumonia. Nature, 14(1), 8103.
  2. Al-Khayyat, M.Z. (2008). Curing of plasmid DNA content of bacteria isolated from patients with urinary tract infection in Mosul city, Thesis for M.Sc., Biotecnology, College of Education, Mosul University, Iraq.
  3. Al Nuimi, A.A.E. (2021). Efficiency of extract of citrus aurantium and punica gronatium plant in neutralizing the resistance of some bacterial species isolated from urinary tract infection, M.Sc. Thesis, Biology, College of education for pure science, University of Mosul, Iraq.
  4. Al-Shamary, E.I., Taha, M.A. (2017). Bio removal of heavy metals by the local isolate Bacillus subtilis. Anbar Journal for Agricultural Sciences, 15, 1992-7479.
  5. Baldwin, J.N., Strickland, R.H., Cox, M.F. (1969). Some properties of the Beta-Lactamase genes in Staphylococcus epidermidis. J Appl Microbiol, 18(4), 628-630.
  6. Bansal, S., Tandon, V. (2011). Contribution of mutations in DNA gyrase and topoisomerase IV genes to ciprofloxacin resistance in Escherichia coli clinical isolates. Int J Antimicrob Agents, 37(3), 253-5.
  7. Bearson, S., Bearson, B., Foster, J.W. (1997). Acid stress responses in enterobacteria. FEMS Microbiol Lett, 147(2), 173-180.
  8. Bennet, P.M. (2008). Plasmid encoded antibiotic resistance: Acquisition and transfer of antibiotic resistance genes in bacteria. British Journal of Pharmacology 153(1), 347-357.
  9. Bhattacherjee, J.W., Pathak, S.P., Gaur, A. (1988). Antibiotic resistance and metal tolerance of coliform bacteria isolated from Gomti River water at Lucknow city. J Gen Appl Microbiol, 34, 391-399.
  10. Bobate, S., Mahalle, S., Dafale, N.A., Bajaj, A. (2023). Emergence of environmental antibiotic resistance: mechanism, monitoring, and management. environmental advances, 13. 100409.
  11. Brown, A.E., Smith, H.R. (2017). Bensons Microbiological Applications. Laboratory Manual in General Microbiology. 14th ed. McGraw-Hill Higher Education– Newyork. 438 pp.
  12. Carlton, B.C., Brown, B.J. (1981). Gene mutation. In: Gerhardt P, Murray, RGE, Costilow, R. N., Nester, E. W., Phillips, G. B. editors. Manual of methods for general Bacteriology, American Society for Microbiology, Washington, 222-242.
  13. Castanie-Cornet, M.P., Penfound, T.A., Smith, D., Elliott, J.F., Foster, J.W. (1999). Control of acid resistance in Escherichia coli. J Bacteriol, 181(11), 3525 -3535.
  14. Churchill, O., Romanus, A.A. (2018). Plasmid curing of antibiotics resistant Escherichia coli isolates from urine and stool samples. J Microbiol and Antimicrob, 11(1), 1-4.
  15. Coluzz, C., Rocha, E.P.C. (2025). The spread of antibiotic resistance is driven by plasmids, among the fastest evolving and of broadest host range. Molecular Biology and Evolution, 42(3),1-2.
  16. Cooksey, D.A. (1993). Copper uptake and resistance in bacteria. Molecular Microbiology, 7(1), 1–5.
  17. Groves, D.J., Short, H., Thewaini, A.J., Young, F.E. (1975). Epidemiology of antibiotic and heavy metal resistance in Bacteria: resistance patterns in staphylococci isolated from populations in Iraq exposed and exposed to heavy metals or antibiotics. Antimicrobial Agent and Chemotherapy, 17(5), 614-621.
  18. Delmar, J.A., Su, C.C., Yu, E.W. (2014). Bacterial multidrug efflux transporters. Annu Rev Biophys, 43, 93-117.
  19. Essa, M.A. and Abdulah, M.A. (2018). Spread and distribution antibiotics and heavy metals resistance and virulence factors possession in some members of enterobacteria isolated from various sources. Rafidain Journal of Science, 27(4), 243-257.
  20. Faisal, R.M. (2010). Application of Low pH as a Curing Agent of Plasmid DNA in Streptomyces as Compared with Other Agents. Rafidain Journal of Science, 21(1), 40-53.
  21. Faisal, R.M., Younis, R.M. (2024). Effect of antibiotics on the expression of pyocyanin synthetic genes in Pseudomonas aeruginosa isolated from different clinical sources of a few hospitals in Mosul, Iraq. Journal of Applied and Natural Science, 16(2), 812.
  22. Gullberg, E., Albrecht, L.M., Karlsson, C., Sandegren, L., Andersson, D.I. (2014). Selection of a multidrug resistance plasmid by sublethal levels of antibiotics and heavy metals. MBio, 5(5), e01918-14.
  23. Wolny-Koladka, K., Zdaniewicz, M. (2021). Antibiotic resistance of Escherichia coli isolated from processing of brewery waste with the addition of bulking agents. Sustainability, 13(18), 10174.
  24. Ezzouhri, L., Castro, E., Moya, M., Espinola, F., Lairini, K. (2009). Heavy metal tolerance of filamentous fungi isolated from polluted sites in tangier Morocco. African Journal of Microbiology Research, 3(2), 35-48.
  25. Liu, J.S., Xie, X.H., Xiao, S.M., Wang, X.M., Zhao, W.J., Tian, Z.L. (2007). Isolation of Leptospirillum ferriphilum by single layered solid medium. J Cent South Univ Technol, 14(4), 467-473.
  26. Liu, X., Wang, D., Wang, H., Feng, E., Zhu, L. (2012). Curing of plasmid PXO1 from Bacillus anthracis using plasmid incompatibility. PLoS ONE, 7(1), e29875.
  27. Majtan, T., Frerman, F.E., Kraus, J. (2010). Effect of cobalt on Escherichia coli metabolism and metalloporphyrin formation. Biometals, 24(2), 335-347.
  28. Malloy, A.M., Campose, J.M. (2011). Extended – Spectrum Beta – lactamase: A brief clinical update. The Pediatric Infectious Disease Journal, 30, 1092-1093.
  29. Manadhar, R., Reghubanshi, B.R., Mahato, M., Neupane, S., Lama, R. (2020). Bacteriological profile and antimicrobial susceptibility patterns of urine culture isolates from patients in a tertiary care center in Lalitpur. BJHS, 5(1), 881-885.
  30. Martinez–Medina, M. (2021). Pathogenic Escherichia coli infections and therapies. Antibiotics, 10(2),112.
  31. Meyer, R. (1974). Alternate forms of the resistant factor R1 in Proteus mirabilis. J Bacteriol, 118(3), 1010-1019.
  32. Michaelis, C., Grohmann, E. (2023). Horizontal gene transfer of antibiotic resistance genes in biofilms. Antibiotics, 12(2), 328.
  33. Mohamad, B. Gh., Al dabbagh, S.Y., Al chalaby, A.Y. (2013). A study on antibiotics and heavy metals resistance in Staphylococcus aureus isolated from mastitis in cows. Rafidain Journal of Science, 24(2),9-18.
  34. Ozdemir, K. (2019). Curing the drug resistance plasmid in E. coli O157:H7. Applied Ecology and Environmental Research, 17(6), 14715-14727.
  35. Padan, E. and Schuldiner, S. (1986). Intracellular pH regulation in bacterial cells. Methods Enzymol, 125, 337-352.
  36. Park, S.B., Park, Y.K., Ha, M.W., Thompson, K.D., Jung, T.S. (2022). Antimicrobial resistance, pathogenic and molecular characterization of Escherichia coli from Diarrheal patients in South Korea. Pathogenes, 11(4), 385.
  37. Paul, D., Chanda, D.D., Chakravarty, A., Bhattacharjee, A. (2020). An insight in to analysis and elimination of plasmid encoding metallo B-lactamases in Pseudomonas aeruginosa. J Global Antimicrobial Resistance, 21, 3-7.
  38. Peter, S., Polsfuss, S., Poledica, M., Hombach, M., Giger, J., Bottger, E., Zbinden, R., Bloemberg, G. (2011). Detection of AmpC Beta–Lactamase Escherichia coli: Comparison of three phenotypic confirmation assays and genetic analysis. J Clin Microbiol, 49(8), 2924-2932.
  39. Philippon, A., Arlet, G., Lagrange, P.H. (1994). Origin and impact of plasmid mediated extended - Spectrum Beta – Lactamases. Eur J Clin Microbiol Infect Dis, 13, 17-29.
  40. Puzari, M., Chetia, P. (2017). RND efflux pump mediated antibiotic resistance in gram negative bacteria, Escherichia coli and Pseudomonas aeruginosa: A major issue worldwide. World J Microbiol Biotechnol, 33(24), 1-8.
  41. Quintelas, C., Fernandes, B., Castro, J., Figueiredo, H. and Tavares, T. (2008). Biosorption of Cr (VI) by three different bacterial species supported on granular activated carbon: a comparative study. J Hazard Mater, 153(1), 799-809.
  42. Quiton, K.G., Doma, J.R.B., Futalan, C.M., Wan, M. (2018). Removal of Chromium (VI) and Zinc (II) from aqueous solution using kaolin supported bacterial biofilms of Gram negative E. coli and Gram positive Staphylococcus epidermidis. Sustainable Environment Research, 28(5), 206-213.
  43. Ramirez-Bayard, I.E., Majia, F., Medina–Sanchez, J.R., Conejo–Reyes, H., Martinez-Torres, A.O. (2023). Prevalence of plasmid–associated tetracycline resistance genes in multidrug–resistant Escherichia coli strains isolated from environmental, animal, and human samples in Panama. Antibiotics, 12(2), 280.
  44. Rosas, S.B., Calzolari, A., Latorre, J.L., Ghitton, N.E., Vasquez, C. (1983). Involvement of a plasmid in Escherichia coli envelope alteration. Journal of Bacteriology, 155, 402-406.
  45. Sengupta, M., Austin, S. (2011). Prevalence and significance of plasmid maintenance functions in the virulence plasmids of pathogenic bacteria. Infection and Immunity, 79(7), 2502-2509.
  46. Sheet, A.S., Al-Shiti, A.Y., Dawood, I.T., Rasol, A.H., Hasouni, A.M., Faisal, R.M. (2024). Phylogeny, susceptibility, and virulence determinants of Morganella morganii isolated from patients with urinary tract infections in Mosul, Iraq. Regulatory Mechanisms in Biosystems, 15(4), 957-961.
  47. Sinha, R.P. (1989). A new simple method of curing plasmid in lactic streptococci (Streptococcus cremoris; Streptococcus lactis, plasmids). FEMS Microbiol Letters, 57(3), 349-352.
  48. Spengler, G., Molnar, A., Molnar, J., Schelz, Z., Sharples, D., Amaral, L. (2006). The mechanism of plasmid curing in bacteria. Current Drug Targets, 7(7), 823-41.
  49. Stepanauskas, R., Glenn, T.C., Jagoe, C.H., Tuckfield, R.C., Lindell, A.H., McArthur, J.V. (2005). Elevated microbial tolerance to metals and antibiotics in metal-contaminated industrial environments. Environ Sci Technol, 39(10), 3671-3678.
  50. Sun, J., Deng, Z., Yan, A. (2014). Bacterial multidrug Efflux pumps: mechanisms, physiology, and pharmacological exploitations. Biochem Biophys Res Commun, 453(2), 254-267.
  51. Tille, P.M. (2017). Baily and scotts diagnostic microbiology, 14th ed. Elsevier Inc. China. 1115pp.
  52. Timmis, N.K., Puhlar, A. (1984). Advances in Molecular Genetics, Springer-Verlary, New York.
  53. Turkyilmaz, O., Darcan, C. (2024). Resistance mechanism of Escherichia coli with different ampicillin resistance levels. Applied Microbiology and Biotechnology, 108(5), 5.
  54. Wilks, J.C., Slonczewski, J.L. (2007). pH of the cytoplasm and periplasm of Escherichia coli: rapid measurement by green fluorescent protein fluorimetry. J Bacteriol, 189(15), 5601-5607.
  55. Yang, H., Wei, S.H., Hobman, J.L., Dodd, C.E.R. (2020). Antibiotic and metal resistance in Escherichia coli isolated from pig slaughter houses in the United Kingdom. Antibiotics, 9(11), 0746.
  56. Zaaen, A.Y., Najeeb, L.M., Amin, S.K. (2013). Role Escherichia coli plasmids halotolerance to resistant of antibiotics. Journal of the University of Anbar for pure science, 7(1),78-89.
  57. Zhang, R., Wang, Y., Leung, P.C., Gu, J.D. (2007). PVC, a small cryptic plasmid from the environmental isolate of Vibrio cholerae MP-1. J Microbiol, 45(3), 193-198.

Similar Articles

You may also start an advanced similarity search for this article.