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bioRxiv · 10.1101/2024.11.25.625267

Microbial virulome and resistome in deep-sea cold seeps pose minimal public health risks

Abstract

Deep-sea cold seeps host high microbial biomass and biodiversity that thrive on hydrocarbon and inorganic compound seepage, exhibiting diverse ecological functions and unique genetic resources. However, potential health risks from pathogenic or antibiotic-resistant microorganisms in these environments remain largely overlooked, especially during resource exploitation and laboratory research. Here, we analyzed 165 metagenomes and 33 metatranscriptomes from 16 global cold seep sites to investigate the diversity and distribution of virulence factors (VFs), antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs). A total of 2,353 VFs are retrieved in 689 MAGs, primarily associated with non-pathogenic functions like adherence. Additionally, cold seeps harbor nearly 100,000 ARGs, as important reservoirs, with high-risk ARGs presenting at low abundance. Compared to other environments, microorganisms in cold seeps exhibit substantial differences in VF and ARG counts, with potential horizontal gene transfer facilitating their spread. These virulome and resistome profiles provide valuable insights into the evolutionary and ecological implications of pathogenicity and antibiotic resistance in extreme deep-sea ecosystems. Collectively, these results indicate that cold seep sediments pose minimal public health risks, shedding lights on environmental safety in deep-sea resource exploitation and research. ImportanceUnderstanding pathogenicity and antibiotic resistance in environmental reservoirs like deep-sea cold seeps is critical for assessing public health risks, particularly with increasing human activities such as deep-sea mining. This study offers the first comprehensive analysis of virulome, resistome, and mobilome profiles in cold seep microbial communities. While cold seeps act as reservoirs for diverse ARGs, high-risk ARGs are rare, and most VFs contribute to non-pathogenic ecological functions. These results highlight the minimal threat to public health posed by cold seeps, providing a reference for monitoring the spread of pathogenicity and resistance in extreme ecosystems and informing environmental safety assessments during deep-sea resource exploitation.

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Zhang, T., Han, Y., Peng, Y., Deng, Z., Shi, W., Xu, X., Wu, Y., Dong, X.. 2024-11-25. Microbial virulome and resistome in deep-sea cold seeps pose minimal public health risks. https://doi.org/10.1101/2024.11.25.625267

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