Biohydrogen production characteristics of Desulfurococcus amylolyticus DSM 16532

Abstract

Desulfurococcus amylolyticus DSM 16532 is a hyperthermophilic archaeon that can grow on cellulose. Due to the relevance of cellulose as a second generation biofuel production substrate this carbon compound was selected for molecular hydrogen (H2) production studies.D. amylolyticus has several genes that are necessary for H2 production, such as pyruvate ferredoxin oxidoreductase, formate dehydrogenase, glyceraldehyde-3-phosphate ferredoxin oxidoreductase and two membrane-bound hydrogenases. Moreover, D. amylolyticus comprises many physiological features that could promote H2 production. Here, the biohydrogen production potential of D. amylolyticus was analysed in batch cultivation mode in bioreactors on cellulose and fructose. Analysing the cell specific biohydrogen production rates revealed that the organism possesses an intriguing physiological potential to produce H2, at rates higher or equal to other known biohydrogen producing strains. However, with respect to the volumetric H2 production rate the limiting factor could be related to low cell densities.Given the physiological capacity of D. amylolyticus the organism could still be envisioned to be optimized as a second generation H2 cell factory.