Implementation of Photobiological H2 Production: The O2 Sensitivity of Hydrogenases

Research output: Contribution to journalArticlepeer-review

70 Scopus Citations

Abstract

The search for the ultimate carbon-free fuel has intensified in recent years, with a major focus on photoproduction of H2. Biological sources of H2 include oxygenic photosynthetic green algae and cyanobacteria, both of which contain hydrogenase enzymes. Although algal and cyanobacterial hydrogenases perform the same enzymatic reaction through metallo-clusters, their hydrogenases have evolved separately, are expressed differently (transcription of algal hydrogenases is anaerobically induced, while bacterial hydrogenases are constitutively expressed), and display different sensitivity to O2 inactivation. Among various physiological factors, the sensitivity of hydrogenases to O2 has been one of the major factors preventing implementation of biological systems for commercial production of renewable H2. This review addresses recent strategies aimed at engineering increased O2 tolerance into hydrogenases (as of now mainly unsuccessful), as well as towards the development of methods to bypass the O2 sensitivity of hydrogenases (successful but still yielding low solar conversion efficiencies). The author concludes with a description of current approaches from various laboratories to incorporate multiple genetic traits into either algae or cyanobacteria to jointly address limiting factors other than the hydrogenase O2 sensitivity and achieve more sustained H2 photoproduction activity.

Original languageAmerican English
Pages (from-to)383-393
Number of pages11
JournalPhotosynthesis Research
Volume125
Issue number3
DOIs
StatePublished - 2015

Bibliographical note

Publisher Copyright:
© 2015 Springer Science+Business Media Dordrecht (outside the USA).

NREL Publication Number

  • NREL/JA-2700-63764

Keywords

  • hydrogenases
  • O2 sensitivity
  • photosynthetic microbes

Fingerprint

Dive into the research topics of 'Implementation of Photobiological H2 Production: The O2 Sensitivity of Hydrogenases'. Together they form a unique fingerprint.

Cite this