Mannitol in six autotrophic stramenopiles and Micromonas

Simon M Dittami, Hoai T N Aas, Berit S Paulsen, Catherine Boyen, Bente Edvardsen, Thierry Tonon

Research output: Contribution to journalArticlepeer-review


Mannitol plays a central role in brown algal physiology since it represents an important pathway used to store photoassimilate. Several specific enzymes are directly involved in the synthesis and recycling of mannitol, altogether forming the mannitol cycle. The recent analysis of algal genomes has allowed tracing back the origin of this cycle in brown seaweeds to a horizontal gene transfer from bacteria, and furthermore suggested a subsequent transfer to the green microalga Micromonas. Interestingly, genes of the mannitol cycle were not found in any of the currently sequenced diatoms, but were recently discovered in pelagophytes and dictyochophytes. In this study, we quantified the mannitol content in a number of ochrophytes (autotrophic stramenopiles) from different classes, as well as in Micromonas. Our results show that, in accordance with recent observations from EST libraries and genome analyses, this polyol is produced by most ochrophytes, as well as the green alga tested, although it was found at a wide range of concentrations. Thus, the mannitol cycle was probably acquired by a common ancestor of most ochrophytes, possibly after the separation from diatoms, and may play different physiological roles in different classes.

Original languageEnglish
Pages (from-to)1237-9
Number of pages3
JournalPlant Signaling and Behavior
Issue number8
Publication statusPublished - Aug 2011


  • Chlorophyta/genetics
  • Diatoms/genetics
  • Mannitol/metabolism
  • Phylogeny
  • Stramenopiles/genetics

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