Metagenomic Analysis of Biocide-Treated Neotropical Oil Reservoir Water Unveils Microdiversity of Thermophile Tepidiphilus.

Katherine Bedoya,Ronald Jaimes-Prada,Juan F Alzate,Julia Acero,Felipe Cabarcas,Jhorman Niño

doi:10.3389/fmicb.2021.741555

Katherine Bedoya, Ronald Jaimes-Prada + Show 4 more

Open Access

https://doi.org/10.3389/fmicb.2021.741555

Copy DOI

Abstract

Microorganisms are capable of colonizing extreme environments like deep biosphere and oil reservoirs. The prokaryotes diversity in exploited oil reservoirs is composed of indigenous microbial communities and artificially introduced microbes. In the present work, high throughput sequencing techniques were applied to analyze the microbial community from the injected and produced water in a neotropical hyper-thermophile oil reservoir located in the Orinoquia region of Colombia, South America. Tepidiphilus is the dominant bacteria found in both injection and produced waters. The produced water has a higher microbial richness and exhibits a Tepidiphilus microdiversity. The reservoir injected water is recycled and treated with the biocides glutaraldehyde and tetrakis-hydroxymethyl-phosphonium sulfate (THPS) to reduce microbial load. This process reduces microbial richness and selects a single Tepidiphilus genome (T. sp. UDEAICP_D1) as the dominant isolate. Thermus and Hydrogenobacter were subdominants in both water systems. Phylogenomic analysis of the injection water dominant Tepidiphilus positioned it as an independent branch outside T. succinatimandens and T. thermophilus lineage. Comparative analysis of the Tepidiphilus genomes revealed several genes that might be related to the biocide-resistant phenotype and the tolerance to the stress conditions imposed inside the oil well, like RND efflux pumps and type II toxin-antitoxin systems. Comparing the abundance of Tepidiphilus protein-coding genes in both water systems shows that the biocide selected Tepidiphilus sp. UDEAICP_D1 genome has enriched genes annotated as ABC-2 type transporter, ABC transporter, Methionine biosynthesis protein MetW, Glycosyltransferases, and two-component system NarL.

Highlights

MATERIALS AND METHODSOil reservoirs exhibit extreme environmental conditions for microbial life such as high temperature, salinity, pressure, anoxic conditions, and presence of heavy metals (Pannekens et al., 2019; Roumagnac et al, 2020)
We report and describe the genomic characteristics of a novel Tepidiphilus isolate found in a hyperthermophile oil well in the Orinoquia region, in Colombia, that endures the treatment with glutaraldehyde and tetrakis-hydroxymethyl-phosphonium sulfate (THPS)
The produced water samples might reflect a closer image of the native oil reservoir microbiota, whereas the injection water microbiota contains indigenous biocide resilient microbes and those artificially introduced, which are resistant to biocides, and that are capable of colonizing piping systems

Summary

Introduction

Oil reservoirs exhibit extreme environmental conditions for microbial life such as high temperature, salinity, pressure, anoxic conditions, and presence of heavy metals (Pannekens et al., 2019; Roumagnac et al, 2020). Indigenous and introduced microorganisms have several effects in petroleum reservoirs and oil exploitation (Ren et al, 2015); some of them are detrimental producing hydrogen sulfide (souring), inducing corrosion or leading to oil pipelines clogging (Okoro et al, 2016; Dolfing and Hubert, 2017; Vigneron et al, 2017). Oxidizing (chlorine and ozone), or non-oxidizing biocides (quaternary ammonium salts, aldehydes, and tetrakis -hydroxymethyl- phosphonium sulfate-THPS) are commonly applied (Gieg et al, 2011). This practice eventually leads to the selection of biocide-resistant microbes (Kahrilas et al, 2015)

Results

Discussion

Conclusion