Plant-fungal ecology. Niche engineering demonstrates a latent capacity for fungal-algal mutualism

Science. 2014 Jul 4;345(6192):94-8. doi: 10.1126/science.1253320.


Mutualistic symbioses shape the evolution of species and ecosystems and catalyze the emergence of biological complexity, yet how such symbioses first form is unclear. We show that an obligate mutualism between the yeast Saccharomyces cerevisiae and the alga Chlamydomonas reinhardtii--two model eukaryotes with very different life histories--can arise spontaneously in an environment requiring reciprocal carbon and nitrogen exchange. This capacity for mutualism is phylogenetically broad, extending to other Chlamydomonas and fungal species. Furthermore, we witnessed the spontaneous association of Chlamydomonas algal cells physically interacting with filamentous fungi. These observations demonstrate that under specific conditions, environmental change induces free-living species to become obligate mutualists and establishes a set of experimentally tractable, phylogenetically related, synthetic systems for studying the evolution of symbiosis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aspergillus nidulans / genetics
  • Aspergillus nidulans / physiology
  • Chlamydomonas reinhardtii / classification
  • Chlamydomonas reinhardtii / metabolism
  • Chlamydomonas reinhardtii / microbiology*
  • Coculture Techniques
  • Genetic Engineering
  • Glucose / metabolism
  • Metabolic Networks and Pathways / genetics
  • Metabolic Networks and Pathways / physiology
  • Neurospora crassa / genetics
  • Neurospora crassa / physiology
  • Nitrites / metabolism
  • Phylogeny
  • Saccharomyces cerevisiae / classification
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae / physiology*
  • Symbiosis / genetics
  • Symbiosis / physiology*


  • Nitrites
  • potassium nitrite
  • Glucose