Correlation of methane production and functional gene transcriptional activity in a peat soil

Thomas E Freitag, James I Prosser

Research output: Contribution to journalArticle

105 Citations (Scopus)

Abstract

The transcription dynamics of subunit A of the key gene in methanogenesis (methyl coenzyme M reductase; mcrA) was studied to evaluate the relationship between process rate (methanogenesis) and gene transcription dynamics in a peat soil ecosystem. Soil methanogen process rates were determined during incubation of peat slurries at temperatures from 4 to 37 degrees C, and real-time quantitative PCR was applied to quantify the abundances of mcrA genes and transcripts; corresponding transcriptional dynamics were calculated from mcrA transcript/gene ratios. Internal standards suggested unbiased recovery of mRNA abundances in comparison to DNA levels. In comparison to those in pure-culture studies, mcrA transcript/gene ratios indicated underestimation by 1 order of magnitude, possibly due to high proportions of inactive or dead methanogens. Methane production rates were temperature dependent, with maxima at 25 degrees C, but changes in abundance and transcription of the mcrA gene showed no correlation with temperature. However, mcrA transcript/gene ratios correlated weakly (regression coefficient = 0.76) with rates of methanogenesis. Methanogen process rates increased over 3 orders of magnitude, while the corresponding maximum transcript/gene ratio increase was only 18-fold. mcrA transcript dynamics suggested steady-state expression in peat soil after incubation for 24 and 48 h, similar to that in stationary-phase cultures. mcrA transcript/gene ratios are therefore potential in situ indicators of methanogen process rate changes in complex soil systems.
Original languageEnglish
Pages (from-to)6679-6687
Number of pages9
JournalApplied and Environmental Microbiology
Volume75
Issue number21
DOIs
Publication statusPublished - Nov 2009

Keywords

  • gene expression profiling
  • methane
  • oxidoreductases
  • reverse transcriptase polymerase chain reaction
  • soil microbiology
  • temperature

Fingerprint Dive into the research topics of 'Correlation of methane production and functional gene transcriptional activity in a peat soil'. Together they form a unique fingerprint.

  • Cite this