6533b837fe1ef96bd12a33eb
RESEARCH PRODUCT
Osmotrophic glucose and leucine assimilation and its impact on EPA and DHA content in algae
Elina T. PeltomaaSami J. Taipalesubject
0106 biological scienceslcsh:Medicinestable isotope labeling010501 environmental scienceslevätMETABOLISMFreshwater Biology01 natural sciencesGeneral Biochemistry Genetics and Molecular BiologyCARBONAlgaemixotrophyPHYTOPLANKTONOmega-3 fatty acidsCryptophytesQUALITYFood scienceStable isotope labelingMixotrophy0105 earth and related environmental scienceschemistry.chemical_classificationisotoopitCOMPETITORSEcologybiologyomega-3 fatty acidsFATTY-ACIDChemistry010604 marine biology & hydrobiologyGeneral Neurosciencelcsh:RFatty acidSUCCESSAssimilation (biology)General MedicineMetabolismbiology.organism_classificationEicosapentaenoic acidLAKEomegarasvahapotOsmotrophyDocosahexaenoic acid1181 Ecology evolutionary biologyGROWTHcryptophytesLeucineGeneral Agricultural and Biological Sciencesdescription
The uptake of dissolved organic compounds, that is, osmotrophy, has been shown to be an efficient nutritional strategy for algae. However, this mode of nutrition may affect the biochemical composition, for example, the fatty acid (FA) contents, of algal cells. This study focused on the osmotrophic assimilation of glucose and leucine by selected seven algal strains belonging to chlorophytes, chrysophytes, cryptophytes, dinoflagellates and euglenoids. Our laboratory experiments with stable isotope labeling showed that osmotrophy occurred in four of the selected seven strains. However, only three of these produced long chain omega-3 FAs eicosapentaenoic acid (EPA; 20:5ω3) and docosahexaenoic acid (DHA; 22:6ω3). High glucose content (5 mg L−1) affected negatively on the total FAs ofMallomonas kalinaeand the total omega-3 FAs ofCryptomonassp. Further, glucose assimilation explained 35% (negative effect) and leucine assimilation 48% (positive effect) of the variation of EPA, DHA and the FAs related to their synthesis inCryptomonassp. Moderate glucose concentration (2 mg L−1) was found to enhance the growth ofCryptomonas ozolinii, whereas low leucine (20 µg L−1) enhanced the growth ofM. kalinae. However, no systematic effect of osmotrophy on growth rates was detected. Our study shows that osmotrophic assimilation of algae is species and compound specific, and that the effects of the assimilated compounds on algal metabolism also varies depending on the species.
year | journal | country | edition | language |
---|---|---|---|---|
2020-01-03 |