A novel metatranscriptomic approach to identify gene expression dynamics during extracellular electron transfer

Area of Science:

• Microbial Ecology
• Biogeochemistry
• Environmental Microbiology

Background:

• Extracellular electron transfer (EET) is a vital microbial process in anoxic environments, influencing global metal biogeochemical cycling.
• Understanding the specific microbes and genes involved in EET is crucial for deciphering microbial community functions.

Purpose of the Study:

• To identify specific EET-active microbes and genes within a diverse microbial biofilm.
• To analyze the community-wide gene expression response to varying EET rates.
• To link functional genes to specific microbial groups involved in EET.

Main Methods:

• Utilized an innovative approach to analyze dynamic community responses to applied EET stimuli.
• Employed metagenomic analysis to obtain draft genomes of abundant and active microbes.
• Applied metatranscriptomic analysis to identify EET-responsive genes.

Main Results:

• Identified Desulfobulbaceae and Desulfuromonadales as the primary microbial groups exhibiting significant gene expression responses to EET.
• Obtained high-coverage draft genomes for these key EET-active microbes.
• Discovered known and novel genes highly responsive to EET stimuli, associated with the identified draft genomes.

Conclusions:

• This study provides a comprehensive view of functional microbes and genes associated with EET activity in complex communities.
• The innovative approach advances the understanding of microbial roles and adaptation mechanisms in response to environmental stimuli.
• Highlights the importance of specific microbial groups in driving biogeochemical processes through EET.