Species-specific response of the soil collembolan gut microbiome and resistome to soil oxytetracycline pollution

Soil antibiotic pollution has caused wide public concern, and the effects of antibiotics on the gut microbiota of soil non-target organisms are poorly understood. Here, we simulate natural exposure scenarios by exposing three species of soil collembolans (Sinella curviseta, Onychiurus yodai, Folsomia candida) to environmentally relevant concentrations of oxytetracycline (OTC) in the soil to explore the response of their gut and surrounding soil microbiota to OTC, including changes in the bacterial community composition and diversity and abundance of antibiotic resistance genes (ARGs). The different collembolan species harbored different gut microbiotas from the surrounding soil. OTC exposure significantly altered the gut microbiota of O. yodai but did not obviously affect that of S. curviseta or F. candida. (o) Entomoplasmatales and Acinetobacter were two main taxa found in O. yodai: the level of the former was significantly increased but that of the latter was reduced with OTC exposure. Moreover, OTC exposure affected the diversity and abundance of ARGs in the gut microbiota of the three collembolan species, with significantly enhanced ARG number and abundance in S. curviseta, especially for genes associated with tetracycline resistance. Our findings indicate that the effects of OTC on soil collembolans are species specific. This study contributes to our understanding of the effects of environmental pollutants on the gut microbiome and resistome of soil animals. (C) 2019 Elsevier B.V. All rights reserved.