Soil oxygen fluctuations as a natural barrier against antibiotic resistant genes propagation: Indications from bacterial network and community assembly

TY - JOUR

T1 - Soil oxygen fluctuations as a natural barrier against antibiotic resistant genes propagation

T2 - Indications from bacterial network and community assembly

AU - Yan, Huicong

AU - Zhu, Xiangyu

AU - Wu, Yajing

AU - Wu, Enhui

AU - Zhu, Xiaomin

AU - Chen, Baoliang

PY - 2025/9/15

Y1 - 2025/9/15

N2 - The impact of redox fluctuations on ARGs propagation in antibiotic-contaminated soil is rarely investigated. In this study, we incubated tetracycline (TC)-contaminated soils under three different oxygen conditions (static anaerobic, oxygen fluctuations, and static aerobic) using a soil microcosm experiment. Soil microbial community composition analysis shows that the bacterial community exhibited higher diversity and stability under fluctuating oxygen conditions compared to continuous aerobic or anaerobic conditions. Network analysis reveals that networks under oxygen fluctuations exhibited higher stability and more competitive interactions. Neutral community model (NCM) analyses indicates that oxygen fluctuations mitigate the selection pressure of tetracycline on soil microbial communities, whereas anaerobic conditions potentiate it. Consequently, the relative abundance of tetracycline resistance genes (TRs) under oxygen fluctuations accounted for approximately 15–57 % of that in anaerobic conditions and 21–88 % in aerobic conditions. Structural equation model (SEM) further reveals that the bacterial community under oxygen fluctuations acts as a barrier to TRs propagation, whereas in aerobic and anaerobic communities, the enrichment of TRs was due to the direct effect of changes in the bacterial community and horizontal gene transfer. This study addresses that soil oxygen fluctuations act as a natural barrier against the propagation of antibiotic resistance genes.

AB - The impact of redox fluctuations on ARGs propagation in antibiotic-contaminated soil is rarely investigated. In this study, we incubated tetracycline (TC)-contaminated soils under three different oxygen conditions (static anaerobic, oxygen fluctuations, and static aerobic) using a soil microcosm experiment. Soil microbial community composition analysis shows that the bacterial community exhibited higher diversity and stability under fluctuating oxygen conditions compared to continuous aerobic or anaerobic conditions. Network analysis reveals that networks under oxygen fluctuations exhibited higher stability and more competitive interactions. Neutral community model (NCM) analyses indicates that oxygen fluctuations mitigate the selection pressure of tetracycline on soil microbial communities, whereas anaerobic conditions potentiate it. Consequently, the relative abundance of tetracycline resistance genes (TRs) under oxygen fluctuations accounted for approximately 15–57 % of that in anaerobic conditions and 21–88 % in aerobic conditions. Structural equation model (SEM) further reveals that the bacterial community under oxygen fluctuations acts as a barrier to TRs propagation, whereas in aerobic and anaerobic communities, the enrichment of TRs was due to the direct effect of changes in the bacterial community and horizontal gene transfer. This study addresses that soil oxygen fluctuations act as a natural barrier against the propagation of antibiotic resistance genes.

KW - Antibiotic resistance genes propagation

KW - Community stability

KW - Natural barrier

KW - Selection pressure

KW - Soil redox fluctuations

UR - https://www.scopus.com/pages/publications/105012207919

U2 - 10.1016/j.jhazmat.2025.139375

DO - 10.1016/j.jhazmat.2025.139375

M3 - Journal article

C2 - 40752166

SN - 0304-3894

VL - 496

JO - Journal of Hazardous Materials

JF - Journal of Hazardous Materials

M1 - 139375

ER -