AUTHOR=Wei Lanzhen , Li Xin , Fan Baoqiang , Ran Zhaoxing , Ma Weimin 

TITLE=A Stepwise NaHSO3 Addition Mode Greatly Improves H2 Photoproduction in Chlamydomonas reinhardtii

JOURNAL=Frontiers in Plant Science

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2018.01532

DOI=10.3389/fpls.2018.01532

ISSN=1664-462X

ABSTRACT=<p>NaHSO<sub>3</sub> addition greatly increases the yield of H<sub>2</sub> photoproduction in a unicellular green alga <italic>Chlamydomonas reinhardtii</italic> through removing O<sub>2</sub> and activating hydrogenase but significantly impairs the activity of PSII, an electron source for H<sub>2</sub> photoproduction. Here, a stepwise addition mode of total 13 mM NaHSO<sub>3</sub>, an optimal concentration for H<sub>2</sub> photoproduction of <italic>C. reinhardtii</italic> identified in a previous one step addition method, significantly improved H<sub>2</sub> photoproduction. Such improvement was believed to be the result of increased residual PSII activity in an anaerobic background, but was at least independent of two alternative electron sinks for H<sub>2</sub> photoproduction, cyclic electron transport around PSI and CO<sub>2</sub> assimilation. Based on the above results, we propose that increased residual PSII activity in an anaerobic environment is an efficient strategy to enhance H<sub>2</sub> photoproduction in <italic>C. reinhardtii</italic>, and the stepwise NaHSO<sub>3</sub> addition mode is a case study in the strategy.</p>