Cyclical patterns affect microbial dynamics in the water basin of a nuclear research reactor

Research output: Contribution to journalArticlepeer-review

Authors

Institutes & Expert groups

  • KUL - Katholieke Universiteit Leuven
  • CEA Saclay - Commissariat à l'énergie atomique
  • Institute of Tropical Medicine
  • UCL - Université catholique de Louvain

Documents & links

Abstract

The BR2 nuclear research reactor in Mol, Belgium, runs in successive phases of operation (cycles) and shutdown, whereby a water basin surrounding the reactor vessel undergoes periodic changes in physico-chemical parameters such as flow rate, temperature, and radiation. The aim of this study was to explore the microbial community in this unique environment and to investigate its long-term dynamics using a 16S rRNA amplicon sequencing approach. Results from two sampling campaigns spanning several months showed a clear shift in community profiles: cycles were mostly dominated by two Operational Taxonomic Units (OTUs) assigned to unclassified Gammaproteobacterium and Pelomonas, whereas shutdowns were dominated by an OTU assigned to Methylobacterium. Although 1 year apart, both campaigns showed similar results, indicating that the system remained stable over this 2-year period. The community shifts were linked with changes in physico-chemical parameters by Nonmetric Multidimensional Scaling (NMDS) and correlation analyses. In addition, radiation was hypothesized to cause a decrease in cell number, whereas temperature had the opposite effect. Chemoautotrophic use of H2 and dead cell recycling are proposed to be used as a strategies for nutrient retrieval in this extremely oligotrophic environment.

Details

Original languageEnglish
Article number744115
Pages (from-to)1-11
Number of pages11
JournalFrontiers in Microbiology
DOIs
Publication statusPublished - 15 Oct 2021

Keywords

  • Nuclear reactor, Ultrapure water, Ionizing radiation, 16S rRNA amplicon sequencing, Aquatic microbiome, Extreme environment

ID: 7321887