title: Phylogenetic Diversity in the Macromolecular Composition of Microalgae.
abstract: The elemental stoichiometry of microalgae reflects their underlying macromolecular composition and influences competitive interactions among species and their role in the food web and biogeochemistry. Here we provide a new estimate of the macromolecular composition of microalgae using a hierarchical Bayesian analysis of data compiled from the literature. The median macromolecular composition of nutrient-sufficient exponentially growing microalgae is 32.2% protein, 17.3% lipid, 15.0% carbohydrate, 17.3% ash, 5.7% RNA, 1.1% chlorophyll-a and 1.0% DNA as percent dry weight. Our analysis identifies significant phylogenetic differences in macromolecular composition undetected by previous studies due to small sample sizes and the large inherent variability in macromolecular pools. The phylogenetic differences in macromolecular composition lead to variations in carbon-to-nitrogen ratios that are consistent with independent observations. These phylogenetic differences in macromolecular and elemental composition reflect adaptations in cellular architecture and biochemistry; specifically in the cell wall, the light harvesting apparatus, and storage pools.
authors.affiliation: Environmental Science Program, Mount Allison University, Sackville, New Brunswick, Canada.
authors.forename: Zoe V
authors.initials: ZV
authors.lastname: Finkel
authors.affiliation: Department of Earth, Atmosphere and Planetary Sciences, MIT, Cambridge, MA, United States of America.
authors.forename: Mick J
authors.initials: MJ
authors.lastname: Follows
authors.affiliation: Environmental Science Program, Mount Allison University, Sackville, New Brunswick, Canada.
authors.forename: Justin D
authors.initials: JD
authors.lastname: Liefer
authors.affiliation: Department of Chemistry and Biochemistry, Mount Allison University, Sackville, New Brunswick, Canada.
authors.forename: Chris M
authors.initials: CM
authors.lastname: Brown
authors.affiliation: Environmental Science Program, Mount Allison University, Sackville, New Brunswick, Canada.
authors.forename: Ina
authors.initials: I
authors.lastname: Benner
authors.affiliation: Department of Math and Computer Science, Mount Allison University, Sackville, New Brunswick, Canada.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Irwin
mesh_terms: D001499:Bayes Theorem; D044822:Biodiversity; D046911:Macromolecular Substances / Q000737:chemistry*; D058086:Microalgae / Q000145:classification* / Q000254:growth & development / Q000378:metabolism*; D010802:Phylogeny; D018521:Plant Physiological Phenomena
chemical_list: D046911:Macromolecular Substances