title: 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 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.
authors.affiliation: Plant Functional Biology and Climate Change Cluster, Faculty of Science, University of Technology, Sydney, New South Wales, Australia.|School of Biological Sciences, Monash University, Melbourne, Victoria, Australia.
authors.forename: Olivia
authors.initials: O
authors.lastname: Sackett
authors.affiliation: Plant Functional Biology and Climate Change Cluster, Faculty of Science, University of Technology, Sydney, New South Wales, Australia.
authors.forename: Katherina
authors.initials: K
authors.lastname: Petrou
authors.affiliation: School of Chemistry and Forensic Science, University of Technology, Sydney, New South Wales, Australia.
authors.forename: Brian
authors.initials: B
authors.lastname: Reedy
authors.affiliation: Centre for Marine Bio-Innovation and Sydney Institute of Marine Science, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Ross
authors.initials: R
authors.lastname: Hill
authors.affiliation: Plant Functional Biology and Climate Change Cluster, Faculty of Science, University of Technology, Sydney, New South Wales, Australia.
authors.forename: Martina
authors.initials: M
authors.lastname: Doblin
authors.affiliation: Centre for Biospectroscopy and School of Biological Sciences, Monash University, Melbourne, Victoria, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Beardall
authors.affiliation: Plant Functional Biology and Climate Change Cluster, Faculty of Science, University of Technology, Sydney, New South Wales, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Ralph
authors.affiliation: School of Biological Sciences and Centre for Biospectroscopy, School of Chemistry, Monash University, Melbourne, Victoria, Australia.
authors.forename: Philip
authors.initials: P
authors.lastname: Heraud
mesh_terms: D002244:Carbon / Q000032:analysis* / Q000378:metabolism; D002245:Carbon Dioxide / Q000032:analysis / Q000378:metabolism; D002247:Carbon Isotopes / Q000032:analysis / Q000378:metabolism; D017377:Diatoms / Q000737:chemistry* / Q000378:metabolism; D020387:Food Chain; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism; D010839:Phytoplankton / Q000737:chemistry* / Q000378:metabolism; D011506:Proteins / Q000032:analysis* / Q000378:metabolism; D012623:Seawater / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
chemical_list: D002247:Carbon Isotopes; D011506:Proteins; D002245:Carbon Dioxide; D002244:Carbon; D009584:Nitrogen