Effects of biodegradable microplastics on the enrichment of antibiotic resistance genes depend on their particle size

Abstract

Microplastics (MPs) are recognized as emerging contaminants that facilitate the dissemination of antibiotic resistance genes (ARGs). However, the ecological mechanisms underlying MP-induced changes soil antibiotic resistance, particularly those mediated by the soil food web, remain largely unexplored. To address this knowledge gap, we conducted a microcosm experiment to investigate how biodegradable MPs (bio-MPs) of different particle sizes influence soil antibiotic resistance through their effects on the soil micro-food web. The results showed that the abundances of functional genes associated with bio-MPs biodegradation were significantly higher in soils amended with 20 μm bio-MPs than in those amended with 300 μm bio-MPs. The biodegradation of 20 μm bio-MP significantly increased the diversity and abundance of ARGs while altering their composition, particularly through the enrichment of genes conferring resistance to multidrug, tetracycline, and aminoglycoside. The tetracycline resistance gene tetA(48), the multidrug resistance gene ompR, and the unclassified resistance gene VanR were the three most abundant ARG subtypes and were significantly enriched in soils amended with 20 μm bio-MPs. Furthermore, amendment with 20 μm bio-MPs significantly increased the total abundance of mobile genetic elements (MGEs), which was positively correlated with ARG abundance. Additionally, amendment with 20 μm bio-MPs enriched Psedomonadota, the predominant hosts of ARGs. Furthermore, bio-MPs destabilized the soil micro-food web, and its stability was negatively associated with ARG abundance. Collectively, these findings suggest that multi-trophic interactions within the soil micro-food web play a previously underappreciated role in regulating antibiotic resistance responses to plastic pollution in soil ecosystems.

Graphical abstract

Keywords

microplastics pollution / antibiotic resistances / soil food web / soil microbial communities / predation pressure

Highlight

	● The biodegradability of bio-MPs is dependent on their particle size.
	● The degradation of bio-MPs drive the selective enrichment of ARGs.
	● Bio-MPs enrich ARGs by directly interventing soil bacterial community.
	● The disturbing of soil micro-food web may also accelerate the dissemination of ARGs.

References

[1] Bhagwat, G., O’Connor, W., Grainge, I., Palanisami, T., 2021. Understanding the fundamental basis for biofilm formation on plastic surfaces: role of conditioning films. Frontiers in Microbiology12, 687118.

[2] Christgen, B., Yang, Y., Ahammad, S.Z., Li, B., Rodriquez, D.C., Zhang, T., Graham, D.W., 2015. Metagenomics shows that low-energy anaerobic−aerobic treatment reactors reduce antibiotic resistance gene levels from domestic wastewater. Environmental Science & Technology49, 2577–2584.

[3] de Vries, F.T., Thébault, E., Liiri, M., Birkhofer, K., Tsiafouli, M.A., Bjørnlund, L., Bracht Jørgensen, H., Brady, M.V., Christensen, S., de Ruiter, P.C., d’Hertefeldt, T., Frouz, J., Hedlund, K., Hemerik, L., Hol, W.H.G., Hotes, S., Mortimer, S.R., Setälä, H., Sgardelis, S.P., Uteseny, K., van der Putten, W.H., Wolters, V., Bardgett, R.D., 2013. Soil food web properties explain ecosystem services across European land use systems. Proceedings of the National Academy of Sciences of the United States of America110, 14296–14301.

[4] Delgado-Baquerizo, M., Hu, H.W., Maestre, F.T., Guerra, C.A., Eisenhauer, N., Eldridge, D.J., Zhu, Y.G., Chen, Q.L., Trivedi, P., Du, S., Makhalanyane, T.P., Verma, J.P., Gozalo, B., Ochoa, V., Asensio, S., Wang, L., Zaady, E., Illán, J.G., Siebe, C., Grebenc, T., Zhou, X.B., Liu, Y.R., Bamigboye, A.R., Blanco-Pastor, J.L., Duran, J., Rodríguez, A., Mamet, S., Alfaro, F., Abades, S., Teixido, A.L., Peñaloza-Bojacá, G.F., Molina-Montenegro, M.A., Torres-Díaz, C., Perez, C., Gallardo, A., García-Velázquez, L., Hayes, P.E., Neuhauser, S., He, J.Z., 2022. The global distribution and environmental drivers of the soil antibiotic resistome. Microbiome10, 219.

[5] Dilkes-Hoffman, L.S., Pratt, S., Lant, P.A., Laycock, B., 2019. The role of biodegradable plastic in solving plastic solid waste accumulation. In: Al-Salem, S.M., ed. Plastics to Energy. Oxford: William Andrew469–505.

[6] Elsawy, M.A., Kim, K.H., Park, J.W., Deep, A., 2017. Hydrolytic degradation of polylactic acid (PLA) and its composites. Renewable and Sustainable Energy Reviews79, 1346–1352.

[7] Faust, K., Raes, J., 2012. Microbial interactions: from networks to models. Nature Reviews Microbiology10, 538–550.

[8] Gigli, M., Negroni, A., Soccio, M., Zanaroli, G., Lotti, N., Fava, F., Munari, A., 2012. Influence of chemical and architectural modifications on the enzymatic hydrolysis of poly(butylene succinate). Green Chemistry14, 2885–2893.

[9] Hibbing, M.E., Fuqua, C., Parsek, M.R., Peterson, S.B., 2010. Bacterial competition: surviving and thriving in the microbial jungle. Nature Reviews Microbiology8, 15–25.

[10] Hu, X.J., Gu, H.D., Sun, X.X., Wang, Y.B., Liu, J.J., Yu, Z.H., Li, Y.S., Jin, J., Wang, G.H., 2024. Metagenomic exploration of microbial and enzymatic traits involved in microplastic biodegradation. Chemosphere348, 140762.

[11] Hu, X.J., Gu, H.D., Wang, Y.B., Liu, J.J., Yu, Z.H., Li, Y.S., Jin, J., Liu, X.B., Dai, Q.W., Wang, G.H., 2022. Succession of soil bacterial communities and network patterns in response to conventional and biodegradable microplastics: a microcosmic study in mollisol. Journal of Hazardous Materials436, 129218.

[12] Jeong, C.B., Won, E.J., Kang, H.M., Lee, M.C., Hwang, D.S., Hwang, U.K., Zhou, B.S., Souissi, S., Lee, S.J., Lee, J.S., 2016. Microplastic size-dependent toxicity, oxidative stress induction, and p-JNK and p-p38 activation in the monogonont rotifer (Brachionus koreanus). Environmental Science & Technology50, 8849–8857.

[13] Kim, S.W., Kim, D., Jeong, S.W., An, Y.J., 2020. Size-dependent effects of polystyrene plastic particles on the nematode Caenorhabditis elegans as related to soil physicochemical properties. Environmental Pollution258, 113740.

[14] Lenoir, L., Persson, T., Bengtsson, J., Wallander, H., Wirén, A., 2007. Bottom–up or top–down control in forest soil microcosms? Effects of soil fauna on fungal biomass and C/N mineralisation. Biology and Fertility of Soils43, 281–294.

[15] Li, C.T., Cui, Q., Li, Y., Zhang, K., Lu, X.Q., Zhang, Y., 2022. Effect of LDPE and biodegradable PBAT primary microplastics on bacterial community after four months of soil incubation. Journal of Hazardous Materials429, 128353.

[16] Li, K., Xu, L.B., Bai, X.Y., Zhang, G.B., Zhang, M.J., Huang, Y., 2024. Potential environmental risks of field bio/non-degradable microplastic from mulching residues in farmland: evidence from metagenomic analysis of plastisphere. Journal of Hazardous Materials465, 133428.

[17] Liu, M.L., Wang, C., Zhu, B., 2023. Drought alleviates the negative effects of microplastics on soil micro-food web complexity and stability. Environmental Science & Technology57, 11206–11217.

[18] Liu, M.L., Wang, C., Zhu, B., 2024a. Independent and combined effects of microplastics pollution and drought on soil bacterial community. Science of the Total Environment913, 169749.

[19] Liu, X.W., Huang, C., Yu, H.X., Yang, Y.N., Ma, L.L., Zhao, B., Zhong, T.Y., Zhang, L.L., Peng, W.H., Gong, W.W., Ding, Y., 2024b. Quorum sensing regulating the heterogeneous transformation of antibiotic resistance genes in microplastic biofilms. Journal of Environmental Chemical Engineering12, 113698.

[20] Luo, G.Y., Liang, B., Cui, H.L., Kang, Y.Y., Zhou, X., Tao, Y., Lu, L., Fan, L., Guo, J.H., Wang, A.J., Gao, S.H., 2023a. Determining the contribution of micro/nanoplastics to antimicrobial resistance: challenges and perspectives. Environmental Science & Technology57, 12137–12152.

[21] Luo, T.Y., Dai, X.H., Wei, W., Xu, Q.X., Ni, B.J., 2023b. Microplastics enhance the prevalence of antibiotic resistance genes in anaerobic sludge digestion by enriching antibiotic-resistant bacteria in surface biofilm and facilitating the vertical and horizontal gene transfer. Environmental Science & Technology57, 14611–14621.

[22] Ma, L.P., Li, A.D., Yin, X.L., Zhang, T., 2017. The prevalence of integrons as the carrier of antibiotic resistance genes in natural and man-made environments. Environmental Science & Technology51, 5721–5728.

[23] Martínez, J.L., 2008. Antibiotics and antibiotic resistance genes in natural environments. Science321, 365–367.

[24] Meng, L.W., Zhao, Y.Z., Li, X.K., Kong, Y.L., Guo, J.B., Liu, M.W., 2021. The effect of bacterial functional characteristics on the spread of antibiotic resistance genes in expanded granular sludge bed reactor treating the antibiotic wastewater. Ecotoxicology and Environmental Safety225, 112714.

[25] Miri, S., Saini, R., Davoodi, S.M., Pulicharla, R., Brar, S.K., Magdouli, S., 2022. Biodegradation of microplastics: better late than never. Chemosphere286, 131670.

[26] Nguyen, B.A.T., Chen, Q.L., He, J.Z., Hu, H.W., 2020. Microbial regulation of natural antibiotic resistance: understanding the protist-bacteria interactions for evolution of soil resistome. Science of the Total Environment705, 135882.

[27] Nguyen, T.B.A., Bonkowski, M., Dumack, K., Chen, Q.L., He, J.Z., Hu, H.W., 2023. Protistan predation selects for antibiotic resistance in soil bacterial communities. The ISME Journal17, 2182–2189.

[28] Peng, C., Zhang, X.F., Zhang, X.Y., Liu, C.G., Chen, Z.Y., Sun, H.W., Wang, L., 2022. Bacterial community under the influence of microplastics in indoor environment and the health hazards associated with antibiotic resistance genes. Environmental Science & Technology56, 422–432.

[29] Rahman, M.H., Mahbub, K.R., Espinoza-Vergara, G., Ritchie, A., Hoque, M.M., Noorian, P., Cole, L., McDougald, D., Labbate, M., 2022. Protozoal food vacuoles enhance transformation in Vibrio cholerae through SOS-regulated DNA integration. The ISME Journal16, 1993–2001.

[30] Ravi, A., Avershina, E., Ludvigsen, J., L’Abée-Lund, T.M., Rudi, K., 2014. Integrons in the intestinal microbiota as reservoirs for transmission of antibiotic resistance genes. Pathogens3, 238–248.

[31] Ren, Z.Y., Guo, H., Jin, H.K., Wang, Y.J., Zhang, G.D., Zhou, J., Qu, G.Z., Sun, Q.H., Wang, T.C., 2023. P, N, and C-related functional genes in SBR system promoted antibiotics resistance gene transmission under polystyrene microplastics stress. Water Research235, 119884.

[32] Rohr, J.R., Barrett, C.B., Civitello, D.J., Craft, M.E., Delius, B., DeLeo, G.A., Hudson, P.J., Jouanard, N., Nguyen, K.H., Ostfeld, R.S., Remais, J.V., Riveau, G., Sokolow, S.H., Tilman, D., 2019. Emerging human infectious diseases and the links to global food production. Nature Sustainability2, 445–456.

[33] Shi, Z., Xiong, L., Liu, T., Wu, W., 2022. Alteration of bacterial communities and Co-occurrence networks as a legacy effect upon exposure to polyethylene residues under field environment. Journal of Hazardous Materials426, 128126.

[34] Starke, R., Kermer, R., Ullmann-Zeunert, L., Baldwin, I.T., Seifert, J., Bastida, F., von Bergen, M., Jehmlich, N., 2016. Bacteria dominate the short-term assimilation of plant-derived N in soil. Soil Biology and Biochemistry96, 30–38.

[35] Sun, Y.Z., Cao, N., Duan, C.X., Wang, Q., Ding, C.F., Wang, J., 2021. Selection of antibiotic resistance genes on biodegradable and non-biodegradable microplastics. Journal of Hazardous Materials409, 124979.

[36] Sun, Y.Z., Duan, C.X., Cao, N., Ding, C.F., Huang, Y., Wang, J., 2022. Biodegradable and conventional microplastics exhibit distinct microbiome, functionality, and metabolome changes in soil. Journal of Hazardous Materials424, 127282.

[37] Taniguchi, I., Yoshida, S., Hiraga, K., Miyamoto, K., Kimura, Y., Oda, K., 2019. Biodegradation of PET: current status and application aspects. ACS Catalysis9, 4089–4105.

[38] Wang, F., Fu, Y.H., Sheng, H.J., Topp, E., Jiang, X., Zhu, Y.G., Tiedje, J.M., 2021a. Antibiotic resistance in the soil ecosystem: a one health perspective. Current Opinion in Environmental Science & Health20, 100230.

[39] Wang, X.M., Lan, B.R., Fei, H.X., Wang, S.Y., Zhu, G.B., 2021b. Heavy metal could drive co-selection of antibiotic resistance in terrestrial subsurface soils. Journal of Hazardous Materials411, 124848.

[40] Wang, Y.F., Liu, Y.J., Fu, Y.M., Xu, J.Y., Zhang, T.L., Cui, H.L., Qiao, M., Rillig, M.C., Zhu, Y.G., Zhu, D., 2024. Microplastic diversity increases the abundance of antibiotic resistance genes in soil. Nature Communications15, 9788.

[41] Wardle, D.A., 2006. The influence of biotic interactions on soil biodiversity. Ecology Letters9, 870–886.

[42] Wardle, D.A., Yeates, G.W., 1993. The dual importance of competition and predation as regulatory forces in terrestrial ecosystems: evidence from decomposer food-webs. Oecologia93, 303–306.

[43] Xu, G.H., Yu, Y., 2021. Polystyrene microplastics impact the occurrence of antibiotic resistance genes in earthworms by size-dependent toxic effects. Journal of Hazardous Materials416, 125847.

[44] Yan, Y.W., Yu, Y.L., Sima, J.K., Geng, C.N., Yang, J., 2023. Aging behavior of microplastics accelerated by mechanical fragmentation: alteration of intrinsic and extrinsic properties. Environmental Science and Pollution Research30, 90993–91006.

[45] Yu, X., Zhou, Z.C., Shuai, X.Y., Lin, Z.J., Liu, Z., Zhou, J.Y., Lin, Y.H., Zeng, G.S., Ge, Z.Y., Chen, H., 2023. Microplastics exacerbate co-occurrence and horizontal transfer of antibiotic resistance genes. Journal of Hazardous Materials451, 131130.

[46] Yuan, M.M., Guo, X., Wu, L.W., Zhang, Y., Xiao, N.J., Ning, D.L., Shi, Z., Zhou, X.S., Wu, L.Y., Yang, Y.F., Tiedje, J.M., Zhou, J.Z., 2021. Climate warming enhances microbial network complexity and stability. Nature Climate Change11, 343–348.

[47] Zhang, J.Y., Xu, Z.X., Chu, W.H., Ju, F., Jin, W., Li, P., Xiao, R., 2023. Residual chlorine persistently changes antibiotic resistance gene composition and increases the risk of antibiotic resistance in sewer systems. Water Research245, 120635.

[48] Zhang, M.J., Zhao, Y.R., Qin, X., Jia, W.Q., Chai, L.W., Huang, M.K., Huang, Y., 2019. Microplastics from mulching film is a distinct habitat for bacteria in farmland soil. Science of the Total Environment688, 470–478.

[49] Zhang, Z.Y., Zhang, Q., Wang, T.Z., Xu, N.H., Lu, T., Hong, W.J., Penuelas, J., Gillings, M., Wang, M.X., Gao, W.W., Qian, H.F., 2022. Assessment of global health risk of antibiotic resistance genes. Nature Communications13, 1553.

[50] Zheng, D.S., Yin, G.Y., Liu, M., Hou, L.J., Yang, Y., Van Boeckel, T.P., Zheng, Y.L., Li, Y., 2022. Global biogeography and projection of soil antibiotic resistance genes. Science Advances8, eabq8015.

[51] Zhou, J.Z., Deng, Y., Luo, F., He, Z.L., Yang, Y.F., 2011. Phylogenetic molecular ecological network of soil microbial communities in response to elevated CO₂. mBio2, e00122–11.

[52] Zhu, D., Ma, J., Li, G., Rillig, M.C., Zhu, Y.G., 2022. Soil plastispheres as hotspots of antibiotic resistance genes and potential pathogens. The ISME Journal16, 521–532.

[53] Zhu, D., Xiang, Q., Yang, X.R., Ke, X., O’Connor, P., Zhu, Y.G., 2019. Trophic transfer of antibiotic resistance genes in a soil detritus food chain. Environmental Science & Technology53, 7770–7781.

[54] Zurier, H.S., Goddard, J.M., 2021. Biodegradation of microplastics in food and agriculture. Current Opinion in Food Science37, 37–44.

Rights & permissions

Higher Education Press