Spotlight on microbial interactions leading to biofouling of landfill methane collection systems
EMSL Project ID
51065
Abstract
Biofilm is the dominant life strategy for microorganisms in environments from pristine aquifers to engineered systems. Biofilm provides structure, protection, and an opportunity for tightly-knit microbial interactions, from mutually beneficial cross-feeding to enhanced predation by viruses and grazers. Despite the importance and prevalence of biofilms, their formation, structure, and ecology are not as well understood as planktonic systems. Engineered environments provide a valuable opportunity to examine naturally forming biofilms at instrumented, monitored, and accessible sites. In partnership with a municipal landfill in Southern Ontario, we propose to characterize the thick, glue-like biofilm that periodically clogs the landfill methane capture system, with the underlying aims of understanding why, how, and when the biofilm forms. Methane capture systems represent unique, high-methane low-oxygen environments. Our work will clarify microbial adaptations to these conditions and the microbial ecology of the biofilm community. High-methane-adapted organisms, especially if methanotrophic, would be of significant interest as potential methane sinks in industrial processes. Samples have been taken from the methane capture system over the summer "bloom" months, with both liquid leachate and solid biofilm (when present) included. We intend to connect key biofilm microorganisms' growth with atmospheric and biogeochemical conditions within the capture system, to better understand triggers for biofilm formation. To accomplish this, we are proposing metaproteomic and meta-metabolomic analyses of four biofilm and six leachate samples, with leachate samples covering the weeks before, during, and after a biofilm bloom for each of two blooms. We will collaborate with EMSL for (1) LC-MS metaproteomic analyses to clarify dominant metabolic strategies in the leachate and biofilm and (2) NMR and GC-MS metabolomics to identify the biofilm matrix composition and to clarify microbial signaling and metabolic hand-off points between microbial community members. We have previously conducted deep metagenomic sequencing, assembly, and genome reconstruction on biofilm and leachate samples, which serve as blueprints for mapping protein data and for modeling metabolic flux within the biofilm microbial community. This project is an initial exploration of the biofilm microbial ecology. Prior metagenomic work shows a moderately complex community that is sourced from the more complex landfill leachate communities. From the multi-faceted meta-omic data developed with EMSL, we will clarify the dynamics governing biofilm formation, including the pioneering organisms necessary for biofilm establishment. We will identify microbial interactions governing biofilm formation and maturation, including an examination of viral predation within the biofilm community. The landfill methane capture system has an unusual atmosphere, and we will examine how microbes respond or adapt to high methane conditions and variable atmospheric conditions. This work would not be possible without the expertise and infrastructure available at EMSL. Our partners at the landfill are focused on biofilm prevention or disruption, as maintaining gas capture efficiency is important for securing sustainable bioenergy and minimizing greenhouse gas emissions. Our future work is aimed at identifying cellular targets for biofilm inhibition and means of effectively dispersing biofilm once formed, and the proposed metaproteomic and metabolomic exploration will help us identify specific targets of interest for future experiments.
Project Details
Project type
Exploratory Research
Start Date
2019-11-26
End Date
2021-03-31
Status
Closed
Released Data Link
Team
Principal Investigator