Gas-Chromatography Mass-Spectrometry (GC-MS) Based Metabolite Profiling Reveals Mannitol as a Major Storage Carbohydrate in the Coccolithophorid Alga Emiliania huxleyi

Metabolites

Toshihiro Obata¹  Steffi Schoenefeld²  Ina Krahnert²  Susan Bergmann²  André Scheffel² 

[1] Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm 14476, Germany;

关键词: coccolithophorid;    Emiliania huxleyi;    metabolite profiling;    GC-MS;    primary carbon metabolism;    mannitol;    isotope labelling;   

DOI  :  10.3390/metabo3010168

来源: mdpi

【 摘 要 】

Algae are divergent organisms having a wide variety of evolutional histories. Although most of them share photosynthetic activity, their pathways of primary carbon metabolism are rather diverse among species. Here we developed a method for gas chromatography-mass spectroscopy (GC-MS) based metabolite profiling for the coccolithophorid alga Emiliania huxleyi, which is one of the most abundant microalgae in the ocean, in order to gain an overview of the pathway of primary metabolism within this alga. Following method optimization, twenty-six metabolites could be detected by this method. Whilst most proteogenic amino acids were detected, no peaks corresponding to malate and fumarate were found. The metabolite profile of E. huxleyi was, however, characterized by a prominent accumulation of mannitol reaching in excess of 14 nmol 10⁶ cells⁻¹. Similarly, the accumulation of the ¹³C label during short term H¹³CO₃⁻ feeding revealed a massive redistribution of label into mannitol as well as rapid but saturating label accumulation into glucose and several amino acids including aspartate, glycine and serine. These results provide support to previous work suggesting that this species adopts C₃ photosynthesis and that mannitol functions as a carbon store in E. huxleyi.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.