Community analysis of 3-amino-1,2,4-triazol-5-one (ATO) and 3-nitro-1,2,4-triazol-5-one (NTO) degrading microbial cultures

Abstract

The degradation of NTO is a growing concern to do its increasing popularity and persistence in the soil as ATO. There is concern over its environmental and health impact, particularly because contamination to water resources is likely due to its high mobility in soil. Understanding the microbial communities that reduce NTO and degrade ATO is important for the development of bioremediation techniques to remove these pollutants from the environment. A culture of ATO degrading microbes was diluted to extinction to reduce the culture to the species essential for ATO degradation. Quantitative polymerase chain reaction (qPCR) analysis showed that the number of species groups present was reduced from 19 to 9, with Terrimonas spp. and Ramlibacter — like spp. the most abundant. Metagenomic data from the culture was used to identify potential biomarker genes related to ATO degradation and qPCR primers were developed. A culture of NTO reducing microbes was measured throughout complete NTO transformation to identify the change in species abundance over time. qPCR analysis showed that Geobacter spp. were consistently found in the highest abundance in the community, and were slightly enriched after the end of the lag phase. The relative abundance of members in each community can give valuable insights into how the community reduces NTO and ATO. Examination of the key members of the community can be used to identify degradation pathways and bioaugmentation strategies for bioremediation. Potential ATO degradation biomarkers identified in this study can be used to monitor and track the in-situ bioremediation of contaminated sites.