A tale of two mixotrophic chrysophytes: Insights into the metabolisms of two Ochromonas species (Chrysophyceae) through a comparison of gene expression

摘要: Ochromonas spp. strains CCMP1393 and BG-1 are phagotrophic phytoflagellates with different nutritional strategies. Strain is an obligate phototroph while strain readily grows in continuous darkness the presence of bacterial prey. Growth gene expression were investigated under conditions allowing phagotrophic, mixotrophic, or phototrophic nutrition. The availability light prey led to differential 42% 45–59% all genes, respectively. Data from compared those a study conducted previously on BG-1, revealed notable differences carbon nitrogen metabolism between 2 congeners similar environmental conditions. utilized amino acids through glycolysis tricarboxylic acid cycle, downregulating harvesting fixation Calvin cycle when both bacteria available. In contrast, upregulation genes related photosynthesis, harvesting, chlorophyll synthesis, for implied that this species more than phagotrophy may have enhanced phototrophy. Cellular content was also significantly higher supplied without Our results thus point very physiological strategies mixotrophic nutrition these closely chrysophyte species.