Abstract
Amphibians defend against pathogens using skin microbial communities, in addition to innate and adaptive immunity. Despite skin microbial communities play a key role in the immune function of amphibians, few studies have focused on the changes in its composition and function. In the present study, we identified the variation in adaptive immunity, as well as the corresponding changes in skin microbiome of Bufo raddei living in a heavy metal polluted area. The adaptive immunity of B. raddei in heavy metal polluted area was significantly lower than that in relatively unpolluted area. Further, different skin bacterial communities were found in the two areas. In the heavy metal polluted area, Actinobacteria and Microbacterium were the dominant bacteria in the skin microbiome of B. raddei, which showed broad-spectrum antibacterial activity. Besides, the antibiotic synthesis was also increased in metabolic pathways. The present study suggested that the adaptive immunity of B. raddei was weakened under long-term heavy metal stress. However, the toads increased the abundance of bacteriostatic bacteria by regulating the composition of skin microbiome, which released a large number of bacteriostatic metabolites and enhanced the host resistance to external pathogens in turn.
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The datasets used or analyzed during the current study are available from the corresponding author on reasonable request.
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The authors are very grateful for the anonymous reviewers and Editors in providing comments about the wording and organization of our manuscript. We also want to thank Editorbar (www.editorbar.com) for English language editing.
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This work was supported by the National Natural Science Foundation of China (No: 31971516), and Foundation for Distinguished Young Talent of Gansu province (No: 20JR10RA647).
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Rui Su: methodology, investigation, resources, writing—original draft, writing—review and editing. Sheng Zhang: methodology, investigation, resources. Xueying Zhang: resources. Shengnan Wang: investigation, resources. Wenya Zhang: methodology, investigation, resources, supervision, conceptualization, writing—review and editing, funding acquisition, formal analysis.
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Su, R., Zhang, S., Zhang, X. et al. Neglected skin-associated microbial communities: a unique immune defense strategy of Bufo raddei under environmental heavy metal pollution. Environ Sci Pollut Res 30, 22330–22342 (2023). https://doi.org/10.1007/s11356-022-23803-1
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DOI: https://doi.org/10.1007/s11356-022-23803-1