Pyrosequencing Analysis Yields Comprehensive Assessment of Microbial Communities in Pilot-Scale Two-Stage Membrane Biofilm Reactors
Description
We studied the microbial community structure of pilot two-stage membrane biofilm reactors (MBfRs) designed to reduce nitrate (NO[subscript 3]–) and perchlorate (ClO[subscript 4]–) in contaminated groundwater. The groundwater also contained oxygen (O[subscript 2]) and sulfate (SO[2 over 4]–), which became important electron sinks that affected the NO[subscript 3]– and ClO[subscript 4]– removal rates. Using pyrosequencing, we elucidated how important phylotypes of each “primary” microbial group, i.e., denitrifying bacteria (DB), perchlorate-reducing bacteria (PRB), and sulfate-reducing bacteria (SRB), responded to changes in electron-acceptor loading. UniFrac, principal coordinate analysis (PCoA), and diversity analyses documented that the microbial community of biofilms sampled when the MBfRs had a high acceptor loading were phylogenetically distant from and less diverse than the microbial community of biofilm samples with lower acceptor loadings. Diminished acceptor loading led to SO[2 over 4]– reduction in the lag MBfR, which allowed Desulfovibrionales (an SRB) and Thiothrichales (sulfur-oxidizers) to thrive through S cycling. As a result of this cooperative relationship, they competed effectively with DB/PRB phylotypes such as Xanthomonadales and Rhodobacterales. Thus, pyrosequencing illustrated that while DB, PRB, and SRB responded predictably to changes in acceptor loading, a decrease in total acceptor loading led to important shifts within the “primary” groups, the onset of other members (e.g., Thiothrichales), and overall greater diversity.
Date Created
The date the item was original created (prior to any relationship with the ASU Digital Repositories.)
2014-07-01
Agent
- Author (aut): Ontiveros-Valencia, Aura
- Author (aut): Tang, Youneng
- Author (aut): Zhao, Heping
- Author (aut): Friese, David
- Author (aut): Overstreet, Ryan
- Author (aut): Smith, Jennifer
- Author (aut): Evans, Patrick
- Author (aut): Rittmann, Bruce
- Author (aut): Krajmalnik-Brown, Rosa
- Contributor (ctb): Biodesign Institute
- Contributor (ctb): Swette Center for Environmental Biotechnology
- Contributor (ctb): Julie Ann Wrigley Global Institute of Sustainability
- Contributor (ctb): School of Sustainability