Genetic Engineering of Cyanobacteria to Enhance Biohydrogen Production from Sunlight and Water
- 510 Downloads
To mitigate global warming caused by burning fossil fuels, a renewable energy source available in large quantity is urgently required. We are proposing large-scale photobiological H2 production by mariculture-raised cyanobacteria where the microbes capture part of the huge amount of solar energy received on earth’s surface and use water as the source of electrons to reduce protons. The H2 production system is based on photosynthetic and nitrogenase activities of cyanobacteria, using uptake hydrogenase mutants that can accumulate H2 for extended periods even in the presence of evolved O2. This review summarizes our efforts to improve the rate of photobiological H2 production through genetic engineering. The challenges yet to be overcome to further increase the conversion efficiency of solar energy to H2 also are discussed.
KeywordsCyanobacteria Hydrogen Hydrogenase Nitrogenase Photobiological H2 production
This study was supported by the Great Lakes Bioenergy Research Center (DOE BER Office of Science DE-FC02-07ER64494) and by the JST PRESTO.
- Ghirardi, M.L., and P. Mohanty. 2010. Oxygenic hydrogen photoproduction—current status of the technology. Current Science 98: 499–507.Google Scholar
- Masukawa, H., M. Mochimaru, and H. Sakurai. 2002a. Disruption of the uptake hydrogenase gene, but not of the bidirectional hydrogenase gene, leads to enhanced photobiological hydrogen production by the nitrogen fixing cyanobacterium Anabaena sp. PCC 7120. Applied Microbiology and Biotechnology 58: 618–624.CrossRefGoogle Scholar
- Mayer, S.M., C.A. Gormal, B.E. Smith, and D.M. Lawson. 2002. Crystallographic analysis of the MoFe protein of nitrogenase from a nifV mutant of Klebsiella pneumoniae identifies citrate as a ligand to the molybdenum of iron molybdenum cofactor (FeMoco). Journal of Biological Chemistry 277: 35263–35266.CrossRefGoogle Scholar
- Wolk, C.P., A. Ernst, and J. Elhai. 1994. Heterocyst metabolism and development. In The molecular biology of cyanobacteria, ed. D.A. Bryant, 769–823. Dordrecht: Kluwer Academic Publishers.Google Scholar