Estrogen induces shift in abundances of specific groups of the coral microbiome

Helena D M Villela,Caio T C C Rachid,Caren L S Vilela,Raquel S Peixoto,Gustavo A S Duarte,Erika P Santoro

doi:10.1038/s41598-021-82387-x

Abstract

Synthetic estrogens such as ethinylestradiol (EE2) are persistent micropollutants that are not effectively removed from wastewater by conventional treatments. These contaminants are released into waterbodies, where they disrupt endocrine systems of organisms and cause harmful effects such as feminization, infertility, reproduction problems and genital malformations. The consequences of this pollution for key marine ecosystems such as coral reefs and their associated microbiomes are underexplored. We evaluated the effects of EE2 concentrations of 100 ng L−1 and 100 µg L−1 on the coral metaorganism Mussismilia harttii. The results indicated no effects on visible bleaching or Fv/Fm ratios in the corals during a 17-day microcosm experiment. However, next-generation sequencing of 16S rDNA revealed a statistically significant effect of high EE2 concentrations on OTU richness, and shifts in specific microbial groups after treatments with or without EE2. These groups might be bioindicators of early shifts in the metaorganism composition caused by EE2 contamination.

Highlights

Tarrant et al.[33] found that corals have the capacity to take up estrogens from the water and accumulate these compounds in their tissue, the consequences of this bioaccumulation are unknown
The coral-associated microbial community is sensitive to environmental changes and can quickly respond and adapt to new environmental conditions, which is important in maintaining the homeostasis of the metaorganism[37,42,44]
We evaluated the effects of EE2 on the coral Mussismilia harttii in a microcosm system, and, for the first time, the impacts of an endocrine-disrupting compounds (EDCs) on a coral-associated microbiome

Summary

Introduction

Tarrant et al.[33] found that corals have the capacity to take up estrogens from the water and accumulate these compounds in their tissue, the consequences of this bioaccumulation are unknown. The coral-associated microbial community is sensitive to environmental changes and can quickly respond and adapt to new environmental conditions, which is important in maintaining the homeostasis of the metaorganism[37,42,44] Different environmental stressors, such as thermal s tress38,45,46, oil[47,48] the presence of pathogens[40,49,50] or ocean a cidification[51,52] can cause shifts in the coral microbiome, which may change their diversity, abundance and functionality for long periods of time[53]. One study showed that the bacterial core associated with corals can respond to a gradient of anthropogenic pollution[55] Different stressors, such as climate change, pollution and overfishing are correlated with an increase in the richness and diversity of specific coral-associated microbes, including the commonly found association of higher abundances of members of Vibrionaceae and Altermonadaceae with stressed and diseased corals[56,57,58]. We evaluated the effects of EE2 on the coral Mussismilia harttii in a microcosm system, and, for the first time, the impacts of an EDC on a coral-associated microbiome

Methods

Results

Conclusion