Light driven CO2 fixation by using cyanobacterial photosystem I and NADPH-dependent formate dehydrogenase.
The ultimate goal of this research is to construct a new direct CO2 fixation system using photosystems in living algae. Here, we report light-driven formate production from CO2 by using cyanobacterial photosystem I (PS I). Formate, a chemical hydrogen carrier and important industrial material, can be produced from CO2 by using the reducing power and the catalytic function of formate dehydrogenase (FDH). We created a bacterial FDH mutant that experimentally switched the cofactor specificity from NADH to NADPH, and combined it with an in vitro-reconstituted cyanobacterial light-driven NADPH production system consisting of PS I, ferredoxin (Fd), and ferredoxin-NADP(+)-reductase (FNR). Consequently, light-dependent formate production under a CO2 atmosphere was successfully achieved. In addition, we introduced the NADPH-dependent FDH mutant into heterocysts of the cyanobacterium Anabaena sp. PCC 7120 and demonstrated an increased formate concentration in the cells. These results provide a new possibility for photo-biological CO2 fixation.
Faculty of Agriculture, Shinshu University, Minamiminowa, Nagano, Japan. m_ihara@shinshu-u.ac.jp
Masaki
M
Ihara
Yusuke
Y
Kawano
Miho
M
Urano
Ayako
A
Okabe
D017033:Anabaena / Q000201:enzymology / Q000378:metabolism* / Q000528:radiation effects*; D057486:Carbon Cycle / Q000528:radiation effects*; D002245:Carbon Dioxide / Q000378:metabolism*; D005560:Formate Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D005561:Formates / Q000378:metabolism; D008027:Light; D009154:Mutation; D009249:NADP / Q000378:metabolism; D045331:Photosystem I Protein Complex / Q000378:metabolism*; D015202:Protein Engineering; D013379:Substrate Specificity
D005561:Formates; D045331:Photosystem I Protein Complex; C030544:formic acid; D002245:Carbon Dioxide; D009249:NADP; C037212:formate dehydrogenase (NADP+); D005560:Formate Dehydrogenases