What is the limit for photoautotrophic plankton growth rates?

TY - JOUR

T1 - What is the limit for photoautotrophic plankton growth rates?

AU - Flynn, Kevin J.

AU - Raven, John A.

N1 - Stimulation for this work came from both the Leverhulme International Network on planktonic mixotrophy (grant F00391V), and from investigations on algal biofuels production funded to K.J.F. through EnAlgae, receiving European Regional Development Funding via Interreg IVB (NWE).

PY - 2017/1/1

Y1 - 2017/1/1

N2 - Knowing the potential maximum photoautotrophic growth rate for planktonic primary producers is fundamental to our understanding of trophic and biogeochemical processes, and of importance in applied phycology. When dayintegrated C-specific growth is considered over natural light:dark cycles, plausible RuBisCO activity (Kcat coupled with cellular RuBisCO content) caps growth to less than a few doubling per day. Prolonged periods of C-specific growth rates above ca. 1.3 d thus appear increasingly implausible. Discrepancies between RuBisCO-capped rates and reported microalgal-specific growth rates, including temperature-growth rate relationships, may be explained by transformational errors in growth rate determinations made by reference to cell counts or most often chlorophyll, or by extrapolations from short-Term measurements. Coupled studies of enzyme activity and day-on-day C-specific growth rates are required to provide definitive evidence of high growth rates. It seems likely, however, that selective pressure to evolve a RuBisCO with a high Kcat (with a likely concomitant increase in Km for CO2) would be low, as other factors such as light limitation (developing during biomass growth due to self-shading), nutrient limitations, CO2 depletion and pH elevation, would all rapidly depress realized specific growth rates.

AB - Knowing the potential maximum photoautotrophic growth rate for planktonic primary producers is fundamental to our understanding of trophic and biogeochemical processes, and of importance in applied phycology. When dayintegrated C-specific growth is considered over natural light:dark cycles, plausible RuBisCO activity (Kcat coupled with cellular RuBisCO content) caps growth to less than a few doubling per day. Prolonged periods of C-specific growth rates above ca. 1.3 d thus appear increasingly implausible. Discrepancies between RuBisCO-capped rates and reported microalgal-specific growth rates, including temperature-growth rate relationships, may be explained by transformational errors in growth rate determinations made by reference to cell counts or most often chlorophyll, or by extrapolations from short-Term measurements. Coupled studies of enzyme activity and day-on-day C-specific growth rates are required to provide definitive evidence of high growth rates. It seems likely, however, that selective pressure to evolve a RuBisCO with a high Kcat (with a likely concomitant increase in Km for CO2) would be low, as other factors such as light limitation (developing during biomass growth due to self-shading), nutrient limitations, CO2 depletion and pH elevation, would all rapidly depress realized specific growth rates.

KW - Microalga

KW - Phytoplankton

KW - RuBisCO

KW - Specific growth rate

KW - Temperature

UR - https://www.scopus.com/pages/publications/85014681019

U2 - 10.1093/plankt/fbw067

DO - 10.1093/plankt/fbw067

M3 - Article

AN - SCOPUS:85014681019

SN - 0142-7873

VL - 39

SP - 13

EP - 22

JO - Journal of Plankton Research

JF - Journal of Plankton Research

IS - 1

ER -