Snapshot prediction of carbon productivity, carbon and protein content in a Southern Ocean diatom using FTIR spectroscopy

Abstract Diatoms, an important group of phytoplankton, bloom annually in the Southern Ocean, covering thousands of square kilometers and dominating the region’s phytoplankton communities. In their role as the major food source to marine grazers, diatoms supply carbon, nutrients and energy to the Sou...

Full description

Bibliographic Details
Published in:The ISME Journal
Main Authors: Sackett, Olivia, Petrou, Katherina, Reedy, Brian, Hill, Ross, Doblin, Martina, Beardall, John, Ralph, Peter, Heraud, Philip
Format: Article in Journal/Newspaper
Language:English
Published: Oxford University Press (OUP) 2015
Subjects:
Online Access:http://dx.doi.org/10.1038/ismej.2015.123
http://www.nature.com/articles/ismej2015123.pdf
http://www.nature.com/articles/ismej2015123
https://academic.oup.com/ismej/article-pdf/10/2/416/56169795/41396_2016_article_bfismej2015123.pdf
Description
Summary:Abstract Diatoms, an important group of phytoplankton, bloom annually in the Southern Ocean, covering thousands of square kilometers and dominating the region’s phytoplankton communities. In their role as the major food source to marine grazers, diatoms supply carbon, nutrients and energy to the Southern Ocean food web. Prevailing environmental conditions influence diatom phenotypic traits (for example, photophysiology, macromolecular composition and morphology), which in turn affect the transfer of energy, carbon and nutrients to grazers and higher trophic levels, as well as oceanic biogeochemical cycles. The paucity of phenotypic data on Southern Ocean phytoplankton limits our understanding of the ecosystem and how it may respond to future environmental change. Here we used a novel approach to create a ‘snapshot’ of cell phenotype. Using mass spectrometry, we measured nitrogen (a proxy for protein), total carbon and carbon-13 enrichment (carbon productivity), then used this data to build spectroscopy-based predictive models. The models were used to provide phenotypic data for samples from a third sample set. Importantly, this approach enabled the first ever rate determination of carbon productivity from a single time point, circumventing the need for time-series measurements. This study showed that Chaetoceros simplex was less productive and had lower protein and carbon content during short-term periods of high salinity. Applying this new phenomics approach to natural phytoplankton samples could provide valuable insight into understanding phytoplankton productivity and function in the marine system.