Oligopeptides Represent a Preferred Source of Organic N Uptake: A Global Phenomenon?

Research output: Contribution to journalArticle

  • External authors:
  • Mark Farrell
  • Paul W. Hill
  • John Farrar
  • Thomas H. DeLuca
  • Paula Roberts
  • Knut Kielland
  • Randy Dahlgren
  • Daniel V. Murphy
  • Phil J. Hobbs
  • Davey L. Jones


Over the past 20 years, our understanding of soil nitrogen (N) cycling has changed with evidence that amino acids are major substrates for both soil microorganisms and plants. However, the recent discovery that plants and microorganisms can directly utilize small peptides in soil needs to be evaluated for its ecological significance, because peptides are released earlier in protein decomposition and thus would provide significant competitive advantage to any organism that can use them directly. We tested whether soil microorganisms took up peptides faster than amino acids across a broad range of ecosystems. We show that l-enantiomeric-peptidic-N is taken up significantly faster than the equivalent monomer, and that this is universal across soils from different ecosystems, with distinct microbial communities. Peptides may have an unrecognized, global, importance in the terrestrial N cycle, providing N to soil microorganisms at an earlier stage of decomposition than previously acknowledged. © 2012 Springer Science+Business Media New York.

Bibliographical metadata

Original languageEnglish
Pages (from-to)133-145
Number of pages12
Issue number1
Publication statusPublished - 2013