Overexpressing Ferredoxins in Chlamydomonas reinhardtii Increase Starch and Oil Yields and Enhance Electric Power Production in a Photo Microbial Fuel Cell.
Ferredoxins (FDX) are final electron carrier proteins in the plant photosynthetic pathway, and function as major electron donors in diverse redox-driven metabolic pathways. We previously showed that overexpression of a major constitutively expressed ferredoxin gene PETF in Chlamydomonas decreased the reactive oxygen species (ROS) level and enhanced tolerance to heat stress. In addition to PETF, an endogenous anaerobic induced FDX5 was overexpressed in transgenic Chlamydomonas lines here to address the possible functions of FDX5. All the independent FDX transgenic lines showed decreased cellular ROS levels and enhanced tolerance to heat and salt stresses. The transgenic Chlamydomonas lines accumulated more starch than the wild-type line and this effect increased almost three-fold in conditions of nitrogen depletion. Furthermore, the lipid content was higher in the transgenic lines than in the wild-type line, both with and without nitrogen depletion. Two FDX-overexpressing Chlamydomonas lines were assessed in a photo microbial fuel cell (PMFC); power density production by the transgenic lines was higher than that of the wild-type cells. These findings suggest that overexpression of either PETF or FDX5 can confer tolerance against heat and salt stresses, increase starch and oil production, and raise electric power density in a PMFC.
Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan 320, Taiwan. hlf326@saturn.yzu.edu.tw.
Li-Fen
LF
Huang
Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan 320, Taiwan. jylin0620@gmail.com.
Ji-Yu
JY
Lin
Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan 320, Taiwan. pku07216@gmail.com.
Kui-You
KY
Pan
Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan 320, Taiwan. hck0903@gate.sinica.edu.tw.
Chun-Kai
CK
Huang
Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan 320, Taiwan. mn32369@hotmail.com.
Ying-Kai
YK
Chu
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001674:Bioelectric Energy Sources; D056804:Biofuels / Q000032:analysis / Q000382:microbiology; D016825:Chlamydomonas reinhardtii / Q000235:genetics* / Q000378:metabolism; D005288:Ferredoxins / Q000235:genetics* / Q000378:metabolism; D006358:Hot Temperature; D008027:Light; D017382:Reactive Oxygen Species / Q000378:metabolism; D055049:Salt Tolerance; D013213:Starch / Q000378:metabolism*; D019076:Transgenes; D015854:Up-Regulation
D001426:Bacterial Proteins; D056804:Biofuels; D005288:Ferredoxins; D017382:Reactive Oxygen Species; D013213:Starch
Chlamydomonas reinhardtii; ferredoxin; heat; oil; salt; starch