HETEROTROPHY AND PHOTOHETEROTROPHY BY ANTARCTIC MICROALGAE: LIGHT‐DEPENDENT INCORPORATION OF AMINO ACIDS AND GLUCOSE 1

• Published in: Journal of Phycology
• Main Authors: Rivkin, Richard B., Putt, Mary
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1987
• Subjects: Antarc*; Antarctic; Antarctica; Sea ice
• Online Access: http://dx.doi.org/10.1111/j.1529-8817.1987.tb02530.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1529-8817.1987.tb02530.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1529-8817.1987.tb02530.x

ABSTRACT Diatoms isolated from the benthic, planktonic and sea ice microbial communities in M c Murdo Sound, Antarctica assimilated ambient concentrations of dissolved amino acids and glucose in both the light and dark. Uptake of amino acids but not glucose was influenced by the iucubation irradiance and amino acid uptake rates were up to 250 times greater than those of glucose. Amino acids were incorporated into proteins and other complex polymers and the rates of assimilation and patterns of polymer synthesis were similar to those of the light‐saturated photosynthetic incorporation of inorganic carbon. This suggests that these diatoms can use exogenous amino acids to synthesize the essential macromolecules for heterotrophic growth. The assimilation of dissolved organic substrates could supplement light‐limited growth during the austral spring and summer as well as potentially support the heterotrophic growth of these diatoms throughout the aphotic polar winter.