TY - JOUR
T1 - Functional redundancy between flavodiiron proteins and NDH-1 in Synechocystis sp. PCC 6803
AU - Nikkanen, Lauri
AU - Santana Sánchez, Anita
AU - Ermakova, Maria
AU - Rögner, Matthias
AU - Cournac, Laurent
AU - Allahverdiyeva, Yagut
N1 - Funding Information:
We thank Prof. Teruo Ogawa for sharing the FDP and NDH-1 mutants and Dr. Henna Mustila for construction of the ΔM55 flv3 strain. Dr. Duncan Fitzpatrick is thanked for expertise and assistance with MIMS. We also thank Dr. Pierre Setif and Dr. Gert Schansker for their expert advice on measuring the DMPs for the DUAL-KLAS-NIR spectrophotometer, and Prof. Jens Appel for critical reading of the manuscript. This work was supported by the Academy of Finland (project no. 315119 to Y.A. and the Finnish Center of Excellence, project no. 307335), the NordForsk Nordic Center of Excellence ‘NordAqua’ (no. 82845) and SFB480, Germany.
Funding Information:
We thank Prof. Teruo Ogawa for sharing the FDP and NDH‐1 mutants and Dr. Henna Mustila for construction of the ΔM55 strain. Dr. Duncan Fitzpatrick is thanked for expertise and assistance with MIMS. We also thank Dr. Pierre Setif and Dr. Gert Schansker for their expert advice on measuring the DMPs for the DUAL‐KLAS‐NIR spectrophotometer, and Prof. Jens Appel for critical reading of the manuscript. This work was supported by the Academy of Finland (project no. 315119 to Y.A. and the Finnish Center of Excellence, project no. 307335), the NordForsk Nordic Center of Excellence ‘NordAqua’ (no. 82845) and SFB480, Germany. flv3
Publisher Copyright:
© 2020 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.
PY - 2020/8/1
Y1 - 2020/8/1
N2 - In oxygenic photosynthetic organisms, excluding angiosperms, flavodiiron proteins (FDPs) catalyze light-dependent reduction of O2 to H2O. This alleviates electron pressure on the photosynthetic apparatus and protects it from photodamage. In Synechocystis sp. PCC 6803, four FDP isoforms function as hetero-oligomers of Flv1 and Flv3 and/or Flv2 and Flv4. An alternative electron transport pathway mediated by the NAD(P)H dehydrogenase-like complex (NDH-1) also contributes to redox hemostasis and the photoprotection of photosynthesis. Four NDH-1 types have been characterized in cyanobacteria: NDH-11 and NDH-12, which function in respiration; and NDH-13 and NDH-14, which function in CO2 uptake. All four types are involved in cyclic electron transport. Along with single FDP mutants (∆flv1 and Δflv3) and the double NDH-1 mutants (∆d1d2, which is deficient in NDH-11,2 and ∆d3d4, which is deficient in NDH-13,4), we studied triple mutants lacking one of Flv1 or Flv3, and NDH-11,2 or NDH-13,4. We show that the presence of either Flv1/3 or NDH-11,2, but not NDH-13,4, is indispensable for survival during changes in growth conditions from high CO2/moderate light to low CO2/high light. Our results show functional redundancy between FDPs and NDH-11,2 under the studied conditions. We suggest that ferredoxin probably functions as a primary electron donor to both Flv1/3 and NDH-11,2, allowing their functions to be dynamically coordinated for efficient oxidation of photosystem I and for photoprotection under variable CO2 and light availability.
AB - In oxygenic photosynthetic organisms, excluding angiosperms, flavodiiron proteins (FDPs) catalyze light-dependent reduction of O2 to H2O. This alleviates electron pressure on the photosynthetic apparatus and protects it from photodamage. In Synechocystis sp. PCC 6803, four FDP isoforms function as hetero-oligomers of Flv1 and Flv3 and/or Flv2 and Flv4. An alternative electron transport pathway mediated by the NAD(P)H dehydrogenase-like complex (NDH-1) also contributes to redox hemostasis and the photoprotection of photosynthesis. Four NDH-1 types have been characterized in cyanobacteria: NDH-11 and NDH-12, which function in respiration; and NDH-13 and NDH-14, which function in CO2 uptake. All four types are involved in cyclic electron transport. Along with single FDP mutants (∆flv1 and Δflv3) and the double NDH-1 mutants (∆d1d2, which is deficient in NDH-11,2 and ∆d3d4, which is deficient in NDH-13,4), we studied triple mutants lacking one of Flv1 or Flv3, and NDH-11,2 or NDH-13,4. We show that the presence of either Flv1/3 or NDH-11,2, but not NDH-13,4, is indispensable for survival during changes in growth conditions from high CO2/moderate light to low CO2/high light. Our results show functional redundancy between FDPs and NDH-11,2 under the studied conditions. We suggest that ferredoxin probably functions as a primary electron donor to both Flv1/3 and NDH-11,2, allowing their functions to be dynamically coordinated for efficient oxidation of photosystem I and for photoprotection under variable CO2 and light availability.
KW - alternative electron transfer
KW - cyanobacteria
KW - Flavodiiron proteins
KW - Flv
KW - Mehler-like reaction
KW - NDH-1
KW - photoprotection
KW - photosynthesis
KW - Synechocystis sp. PCC 6803
UR - https://www.scopus.com/pages/publications/85087732714
U2 - 10.1111/tpj.14812
DO - 10.1111/tpj.14812
M3 - Article
C2 - 32394539
AN - SCOPUS:85087732714
SN - 0960-7412
VL - 103
SP - 1460
EP - 1476
JO - The Plant Journal
JF - The Plant Journal
IS - 4
ER -