@article {xie_disentangling_2021,
	title = {Disentangling the Effects of Ocean Carbonation and Acidification on Elemental Contents and Macromolecules of the Coccolithophore Emiliania huxleyi},
	journal = {Frontiers in Microbiology},
	volume = {12},
	year = {2021},
	pages = {3188},
	abstract = {Elemental contents change with shifts in macromolecular composition of marine phytoplankton. Recent studies focus on the responses of elemental contents of coccolithophores, a major calcifying phytoplankton group, to changing carbonate chemistry, caused by the dissolution of anthropogenically derived CO2 into the surface ocean. However, the effects of changing carbonate chemistry on biomacromolecules, such as protein and carbohydrate of coccolithophores, are less documented. Here, we disentangled the effects of elevated dissolved inorganic carbon (DIC) concentration (900 to 4,930μmolkg-1) and reduced pH value (8.04 to 7.70) on physiological rates, elemental contents, and macromolecules of the coccolithophore Emiliania huxleyi. Compared to present DIC concentration and pH value, combinations of high DIC concentration and low pH value (ocean acidification) significantly increased pigments content, particulate organic carbon (POC), and carbohydrate content and had less impact on growth rate, maximal relative electron transport rate (rETRmax), particulate organic nitrogen (PON), and protein content. In high pH treatments, elevated DIC concentration significantly increased growth rate, pigments content, rETRmax, POC, particulate inorganic carbon (PIC), protein, and carbohydrate contents. In low pH treatments, the extents of the increase in growth rate, pigments and carbohydrate content were reduced. Compared to high pH value, under low DIC concentration, low pH value significantly increased POC and PON contents and showed less impact on protein and carbohydrate contents; however, under high DIC concentration, low pH value significantly reduced POC, PON, protein, and carbohydrate contents. These results showed that reduced pH counteracted the positive effects of elevated DIC concentration on growth rate, rETRmax, POC, PON, carbohydrate, and protein contents. Elevated DIC concentration and reduced pH acted synergistically to increase the contribution of carbohydrate{\textendash}carbon to POC, and antagonistically to affect the contribution of protein{\textendash}nitrogen to PON, which further shifted the carbon/nitrogen ratio of E. huxleyi.},
	keywords = {rcc, RCC1266},
	issn = {1664-302X},
	doi = {10.3389/fmicb.2021.737454},
	url = {https://www.frontiersin.org/article/10.3389/fmicb.2021.737454},
	author = {Xie, Emei and Xu, Kui and Li, Zhengke and Li, Wei and Yi, Xiangqi and Li, Hongzhou and Han, Yonghe and Zhang, Hong and Zhang, Yong}
}
@article {zhang_growth-dependent_2021,
	title = {Growth-dependent changes in elemental stoichiometry and macromolecular allocation in the coccolithophore Emiliania huxleyi under different environmental conditions},
	journal = {Limnology and Oceanography},
	volume = {66},
	number = {8},
	year = {2021},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1002/lno.11854},
	pages = {2999{\textendash}3009},
	abstract = {The growth rate hypothesis (GRH) posits an increase in ribosomal ribonucleic acid (RNA) content, and therefore cellular phosphorus (P), with increasing growth rate. There is evidence that the GRH may not apply to phytoplankton under all conditions. Here, we experimentally controlled four conditions (light, temperature, pH, and CO2) to alter the growth rate of Emiliania huxleyi, a biogeochemically important coccolithophorid, and monitored changes in RNA, protein, and carbohydrate content. We show that an increase in growth rate caused by increasing light, pH, and CO2 resulted in increased RNA per unit of organic carbon (RNA : POC), but that increasing temperature, leading to increase of growth rate, resulted in a decrease in RNA : POC. Protein per unit of organic carbon (protein : POC) increased in our increased temperature, pH, and CO2 treatments that increased growth rate, but there was little change in protein : POC in our light treatment despite it inducing the same increase in growth rate. Carbohydrate per unit of organic carbon (Carbohydrate : POC) increased with growth rate under increased light and CO2 but did not vary significantly in the temperature or pH treatments. These results indicate that physiological acclimation to specific environmental conditions can lead to contrasting patterns in RNA, protein, and carbohydrate composition and therefore contrasting changes in carbon : nitrogen : phosphorus ratios with growth rate in E. huxleyi.},
	keywords = {rcc, RCC1266},
	issn = {1939-5590},
	doi = {10.1002/lno.11854},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/lno.11854},
	author = {Zhang, Yong and Li, Zhengke and Schulz, Kai G. and Hu, Yingyu and Irwin, Andrew J. and Finkel, Zoe V.}
}
