Effects of Heavy Metals on Bacterial Growth, Biochemical Properties and Antimicrobial Susceptibility

Faith Ngwewa^{1, 2,} , George Kasali³, Ernatus M. Mkupasi⁴ and Abdul A. S. Katakweba⁵

¹Inter- University Council for East Africa, P.O Box 7110, Kampla, Uganda; Sponsor

²Southern African Centre for Infectious Disease Surveillance (SACIDS), P.O Box 3297, Sokoine University of Agriculture, Morogoro, Tanzania; Sponsor;Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, P. O. Box 3015, Chuo Kikuu, Morogoro, Tanzania; Registered Department at SUA

³Department of Biological Sciences, Copperbelt University, P.O Box 21692, Kitwe, Zambia

⁴Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, P. O. Box 3015, Chuo Kikuu, Morogoro, Tanzania; Registered Department at SUA

⁵Institute of Pest Management, Sokoine University of Agriculture, P.O.BOX 3110, Chuo Kikuu, Morogoro, Tanzania

Cite this paper:
Faith Ngwewa, George Kasali, Ernatus M. Mkupasi and Abdul A. S. Katakweba. Effects of Heavy Metals on Bacterial Growth, Biochemical Properties and Antimicrobial Susceptibility. Journal of Applied & Environmental Microbiology. 2022; 10(1):9-16. doi: 10.12691/jaem-10-1-2

Abstract

Heavy metals are metallic elements that occur naturally and have a high atomic weight and a density which is five times greater than the density of water. Several studies have demonstrated that metal contamination in natural environments could have an important role in the development and spread of antimicrobial resistance. This is of particular concern, considering that heavy metals usually occur at higher levels than pharmaceutically produced antimicrobials. Also, the bio-accumulative and non-biodegradable nature of heavy metals may result in long- term antimicrobial resistance selection pressure. Therefore, this study assessed the effects of Copper, Cobalt, Cadmium, Zinc and Lead salts on growth, biochemical properties and antimicrobial susceptibility of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus to commonly used antimicrobials. The selected bacteria were exposed to varying concentrations of the heavy metal salts ranging from 1 ppm to 1000 ppm after which growth was measured using a spectrophotometer. The effect on biochemical reactions and antimicrobial susceptibility were also tested by the use of conventional biochemical tests and Kirby-Bauer disk diffusion methods respectively. Different heavy metals affected the growth of each individual microorganism differently. Despite that, the growth of E. coli, P. aeruginosa and S. aureus was observed to be inversely proportional to the concentrations of the heavy metals used. Following exposure to heavy metals, E. coli and S. aureus showed no changes in their biochemical properties but P. aeruginosa gave a positive urease result contrary to the control. E. coli developed resistance to Levofloxacin, Meropenem and Tetracycline while S. aureus to Azithromycin and Gentamicin and P. aeruginosa developed resistance only to Meropenem. These results confirm the adverse effects of heavy metals on bacterial growth and reveals that heavy metals can cause changes in some biochemical properties of bacteria that produce any of these properties under stressful growing conditions. This research also supports the findings that heavy metals enhance the development of antimicrobial resistance in otherwise antimicrobial sensitive strains of bacteria. This study therefore, gives insight into the likely state of the proliferation of heavy metal induced antimicrobial resistance in heavy metal contaminated areas.

Keywords:
heavy metals antimicrobial resistance resistance mechanisms toxicity biochemical reactions bacterial growth

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

References:

[1]	Tchounwou, P.B., Yedjou, C.G. and Patlolla, A.K. “Heavy metal toxicity and the environment,” Experientia Supplementum, 101. 133-164. 2012.
[2]	Hashim, M.A., Mukhopadhyay, S., Sahu, J.N. and Sengupta, B. “Remediation technologies for heavy metal contaminated groundwater,” Journal of Environmental Management, 92 (10). 2355-2388. Jun.2011.
[3]	Wuana, R.A. and Okieimen, F.E. “Heavy metals in contaminated soils: A review of sources, chemistry, risks and best available strategies for remediation,” International Scholarly Research Notices Ecology Journal, 12. 1-20. Oct.2011.
[4]	Varalakshmi, L.R. and Ganeshamurthy, A.N. “Heavy metal contamination of water bodies, soils and vegetables in peri-urban areas of Bangalore city of India,” Journal of Horticultural Science, 7. 62-67. Jun.2012.
[5]	D’Amore, J.J., Al-Abed, S.R., Scheckel, K.G. and Ryan, J.A. “Methods for speciation of metals in soils: A review,” Journal of Environmental Quality, 34 (5). 1707-1745. Sept.2005.
[6]	Turpeinen, R., Kairesalo, T. and Haggblom, M. “Microbial community structure in arsenic, chromium and copper contaminated soils,” FEMS Microbiology Ecology, 47 (1). 39-50. Jan.2004.
[7]	Lakherwal, D. “Adsorption of heavy metals: a review,” International Journal of Environmental Research Development, 4 (1). 41-48. 2014.
[8]	Nielsen, K.M., Bøhn, T. and Townsend, J.P. “Detecting rare gene transfer events in bacterial populations,” Frontiers of Microbiology, 4. 415. Jan.2014.
[9]	Siddiquee, S., Rovina, K. and Azad, S.A. “Heavy metal contaminants removal from wastewater using the potential flamentous fungi biomass: a review,” Journal of Microbial and Biochemical Technology, 7 (6). 384-393. 2015.
[10]	Wang S and Shi X. “Molecular mechanisms of metal toxicity and carcinogenesis,” Molecular and Cellular Biochemistry, 222. 3-9. Jun.2001.
[11]	Chang, L.W., Magos, L. and Suzuki, T, Toxicology of Metals, CRC Press, Boca Raton. Florida, USA, 1996.
[12]	Beyersmann, D. and Hartwig A. “Carcinogenic metal compounds: recent insight into molecular and cellular mechanisms,” Archives of Toxicology, 82 (8). 493-512. May.2008.
[13]	Rupp, M.E., Fitzgerald, T., Marion, N., Helget, V., Puumala, S., Anderson, J.R. and Fey, P.D. “Effect of silver-coated urinary catheters: efficacy, cost-effectiveness, and antimicrobial resistance,” American Journal of Infection Control, 32 (8). 445-450. Dec.2004.
[14]	Yazdankhah, S., Rudi, K. and Bernhoft, A. “Zinc and copper in animal feed-development of resistance and co-resistance to antimicrobial agents in bacteria of animal origin,” Microbial Ecology in Health and Disease, 25 (1). 25862-25865. Sept.2014.
[15]	Bruins, M. R., Kapil S. and Oehme, F.W. “Microbial resistance to metals in the environment,” Ecotoxicology and Environmental Safety, 45 (3). 198-207. Mar.2000.
[16]	Choudhury, R. and Srivastava, S. “Zinc resistance mechanisms in bacteria,” Current Science, 81 (7). 768-775. Oct.2001.
[17]	Alonso, A., Sanchez, P. and Martinez, J.L. “Environmental selection of antibiotic resistance genes,” Environmental Microbiology, 3 (1). 1-9. 2001.
[18]	Yazdankhah, S., Skjerve, E. and Wasteson, Y. “Antimicrobial resistance due to the content of potentially toxic metals in soil and fertilizing products,” Microbial Ecology of Health Disease, 29 (1). 1548248. Dec.2018.
[19]	Stepanauskas, R., Glenn, T.C., Jagoe, C.H., Tuckfield, R.C., Lindell, A.H. and McArthur, J.V. “Elevated microbial tolerance to metals and antibiotics in metal-contaminated industrial environments,” Environmental Science and Technology, 39 (10). 3671-3678. Apr.2005.
[20]	Aung, W.L., Hlaing, N.N. and Aye, N.K. “Biosorption of lead (Pb 2+) by using Chlorella vulgaris,” International Journal of Chemical, Environmental and Biological Sciences, 1 (2). 2320-4087. 2013.
[21]	Gautam, R.K., Soni, S. and Chattopadhyaya, M.C. “Functionalized magnetic nanoparticles for environmental remediation,” Handbook of Research on Diverse Applications of Nanotechnology in Biomedicine, Chemistry and Engineering. 2014. 34pp.
[22]	Turner R.J. “Metal-based antimicrobial strategies,” Microbial biotechnology, 10 (5). 1062-1065. Jul. 2017.
[23]	World Health Organization (2017). Media Centre. WHO publishes list of bacteria for which new antibiotics are urgently needed [http://www.who.int/mediacentre/news/releases/2017/bacteria-antibiotics-needed/en/] accessed on 15/7/2021.
[24]	Zumdahl, S. and DeCoste, D, Introductory Chemistry (8th Edition), Cengage Learning EMEA, UK., 2014, 759 pp.
[25]	Rao, A., Pratibha, S., Neelakantham, S., Shashidhara, N. and Venkatesh, T. “Effect of Lead on Microorganisms with Respect to Antibiogram, Glucose and Amino Acid Metabolism,” Journal of Krishna Institute of Medical Sciences University, 3 (2). 43-54. Dec.2014.
[26]	Barrow, G.I. and Feltham, R.K.A. Cowan and Steel’s Manual for Identification of Medical Bacteria, (3rd. Ed.), Cambridge University Press, Cambridge. 1993. 216pp.
[27]	Bauer, A., Kirby, W., Sherris, J.C. and Turck, M. “Antibiotic susceptibility testing by a standardized single disk method,” American Journal of Clinical Pathology, 45 (4). 493-496. 1966.
[28]	Clinical and Laboratory Standards Institute. Performance Standards for Antimicrobial Susceptibility Testing (31st Ed.), CLSI Supplement M100. Wayne. 2021. 315pp.
[29]	Eghomwanre, A.F., Obayagbona, N.O., Osarenotor, O. and Enagbonma, B.J. “Evaluation of antibiotic resistance patterns and heavy metals tolerance of some bacteria isolated from contaminated soils and sediments from warri, Delta State, Nigeria,” Journal of Applied Science and Environmental Management, 20 (2). 287-291. Jul. 2016.
[30]	Fashola, M.O., Ngole-Jeme, V.M. and Babalola, O.O. “Heavy metal pollution from gold mines: Environmental effects and bacterial strategies for resistance,” International Journal of Environmental Research and Public Health, 13 (11). 1047. Oct. 2016.
[31]	Nies, D.H. “Microbial heavy-metal resistance,” Applied Microbiology and Biotechnology, 51 (6). 730-750. Jun. 1999.
[32]	Levinson, H.S., Mahler, I., Blackwelder, P. and Hood T. “Lead resistance and sensitivity in Staphylococcus aureus,” FEMS Microbiology Letter, 145 (3). 421-425. Dec.1996.
[33]	Nies, D.H. and Silver S. “Ion efflux systems involved in bacteria metal resistances,” Journal for Industrial Microbiology, 14. 186-199. Feb.1995.
[34]	Chudobova, D., Dostalova, S., Ruttkay-Nedecky, B., Guran, R., Rodrigo, M.A.M., Tmejova, K., Krizkova, S., Zitka, O., Adam, V. and Kizek, R. “The effect of metal ions on Staphylococcus aureus revealed by biochemical and mass spectrometric analyses,” Microbiological Research, 170. 147-156. Jan.2015.
[35]	Liu, Y., Zhang, J. and Ji, Y. “Environmental factors modulate biofilm formation by Staphylococcus aureus,” Science Progress, 103 (1). 1-14. Jan.2020.
[36]	Jassal, M.S., Nedeltchev, G.G., Lee, J.H., Choi, S.W., Atudorei, V., Sharp, Z.D., Deretic, V., Timmins, G.S. and Bishai, W.R. “13[C]-urea breath test as a novel point-of-care biomarker for tuberculosis treatment and diagnosis,” PLoS One, 27 (5). 1-9. Aug.2010.
[37]	Raissy, H.H., Timmins, G., Davies, L., Heynekamp, T., Harkins, M., Sharp, D.Z. and Kelly, W.H. “A Proof of Concept Study to Detect Urease Producing Bacteria in Lungs Using Aerosolized 13C-Urea,” Pediatric Allergy, Immunology, and Pulmonology, 29 (2). 68-73. Jun.2016.
[38]	Difco and BBL Manual. BD Diagnostics Manual of Microbiological Culture Media. (2nd Edition). Sparks, Maryland. 2009. 700pp.
[39]	Kim, J., Lee, S. and Choi, S. “Copper resistance and its relationship to erythromycin resistance in Enterococcus isolates from bovine milk samples in Korea,” Journal of Microbiology, 50 (3). 313-339. Jun.2012.
[40]	Rajbanshi, A. “Study on heavy metal resistant bacteria in guheswori sewage treatment plant,” Our Nature, 6 (1). 52-57. Mar.2008.
[41]	Nies, D.H. “Efflux-mediated heavy metal resistance in prokaryotes,” FEMS Microbiology Reviews, 27. 313-339. Jun.2003.
[42]	Li, X., Gu, A.Z., Zhang, Y., Xie, B., Li, D. and Chen, J. “Sub-lethal concentrations of heavy metals induce antibiotic resistance via mutagenesis,” Journal of Hazardous Materials, 369. 9-16. May.2019.
[43]	Sarkar, S.K., Dutta, M., Chowdhury, C., Kumar, A. and Ghosh, A.S. “PBP5, PBP6 and DacD play different roles in intrinsic beta-lactam resistance of Escherichia coli,” Microbiology, 157 (9). 2702-2707. Sept.2011.
[44]	Orth, P., Schnappinger, D., Hillen, W., Saenger, W. and Hinrichs, W. “Structural basis of gene regulation by the tetracycline inducible Tet repressor-operator system,” National Structure Biology, 7(3). 215-219. Mar.2000.
[45]	Perron, K., Caille, O., Rossier, C., Van-Delden, C. and Dumas, J. L. “CzcR-CzcS, a two-component system involved in heavy metal and carbapenem resistance in Pseudomonas aeruginosa,” Journal of Biological Chemistry, 279 (10). 8761-8768. Mar.2004.
[46]	Lamont, I.L., Konings, A.F. and Reid, D.W. “Iron acquisition by Pseudomonas aeruginosa in the lungs of patients with cystic fibrosis,” BioMetals, 22 (1). 53-60. Jan.2009.
[47]	Teitzel, G.M. and Parsek, M.R. “Heavy metal resistance of biofilm and planktonic Pseudomonas aeruginosa, Applied and Environment Microbiology 69 (4). 2313-2320. Apr.2003.
[48]	Gomez-Sanz, E., Kadlec, K., Fessler, A.T., Zarazaga, M., Torres, C. and Schwarz, S. “Novel erm(T)-carrying multi-resistance plasmids from porcine and human isolates of methicillin-resistant Staphylococcus aureus ST398 that also harbor cadmium and copper resistance determinants,” Antimicrobial Agents and Chemotherapy, 57 (7). 3275-3282. Apr.2013.
[49]	Aarestrup, F.M., Cavaco, L. and Hasman, H. “Decreased susceptibility to zinc chloride is associated with methicillin resistant Staphylococcus aureus CC398 in Danish swine,” Journal of Veterinary Microbiology, 142 (3-4). 455-457. May.2010.
[50]	Cavaco, L.M., Hasman, H., Stegger, M., Andersen, P.S., Skov, R. and Fluit, A.C. “Cloning and occurrence of czrC, a gene conferring cadmium and zinc resistance in methicillin-resistant Staphylococcus aureus CC398 isolates,” Antimicrobial Agents and Chemotherapy, 54 (9). 3605-3608. Sept.2010.