Live cyanobacteria produce photocurrent and hydrogen using both the respiratory and photosynthetic systems.
Gadiel SaperDan KallmannFelipe ConzueloFangyuan ZhaoTünde N TóthVarda LiveanuSagit MeirJedrzej SzymanskiAsaph AharoniWolfgang SchuhmannAvner RothschildGadi SchusterNoam AdirPublished in: Nature communications (2018)
Oxygenic photosynthetic organisms perform solar energy conversion of water and CO2 to O2 and sugar at a broad range of wavelengths and light intensities. These cells also metabolize sugars using a respiratory system that functionally overlaps the photosynthetic apparatus. In this study, we describe the harvesting of photocurrent used for hydrogen production from live cyanobacteria. A non-harmful gentle physical treatment of the cyanobacterial cells enables light-driven electron transfer by an endogenous mediator to a graphite electrode in a bio-photoelectrochemical cell, without the addition of sacrificial electron donors or acceptors. We show that the photocurrent is derived from photosystem I and that the electrons originate from carbohydrates digested by the respiratory system. Finally, the current is utilized for hydrogen evolution on the cathode at a bias of 0.65 V. Taken together, we present a bio-photoelectrochemical system where live cyanobacteria produce stable photocurrent that can generate hydrogen.
Keyphrases
- electron transfer
- induced apoptosis
- cell cycle arrest
- visible light
- quantum dots
- solar cells
- physical activity
- signaling pathway
- stem cells
- sensitive detection
- endoplasmic reticulum stress
- oxidative stress
- respiratory tract
- risk assessment
- cell death
- gold nanoparticles
- cell therapy
- mesenchymal stem cells
- cell proliferation
- combination therapy
- bone marrow
- kidney transplantation
- reduced graphene oxide