Effect of nitrogen availability on the poly-3-D-hydroxybutyrate accumulation by engineered Saccharomyces cerevisiae.

Poly-3-D-hydroxybutyrate (or PHB) is a polyester which can be used in the production of biodegradable plastics from renewable resources. It is naturally produced by several bacteria as a response to nutrient starvation in the excess of a carbon source. The yeast Saccharomyces cerevisiae could be an alternative production host as it offers good inhibitor tolerance towards weak acids and phenolic compounds and does not depolymerize the produced PHB.

Biofilm formation by designed co-cultures of Caldicellulosiruptor species as a means to improve hydrogen productivity.

Background: Caldicellulosiruptor species have gained a reputation as being among the best microorganisms to produce hydrogen (H2) due to possession of a combination of appropriate features. However, due to their low volumetric H2 productivities (Q H2), Caldicellulosiruptor species cannot be considered for any viable biohydrogen production process yet. In this study, we evaluate biofilm forming potential of pure and co-cultures of Caldicellulosiruptor saccharolyticus and Caldicellulosiruptor owensensis in continuously stirred tank reactors (CSTR) and up-flow anaerobic (UA) reactors.

Evaluation of assimilatory sulphur metabolism in Caldicellulosiruptor saccharolyticus.

Caldicellulosiruptor saccharolyticus has gained reputation as being among the best microorganisms to produce H2 due to possession of various appropriate features. The quest to develop an inexpensive cultivation medium led to determine a possible replacement of the expensive component cysteine, i.e.

Assessment of metabolic flux distribution in the thermophilic hydrogen producer Caloramator celer as affected by external pH and hydrogen partial pressure.

Background: Caloramator celer is a strict anaerobic, alkalitolerant, thermophilic bacterium capable of converting glucose to hydrogen (H2), carbon dioxide, acetate, ethanol and formate by a mixed acid fermentation. Depending on the growth conditions C. celer can produce H2 at high yields.

Thermophilic biohydrogen production: how far are we?

Apart from being applied as an energy carrier, hydrogen is in increasing demand as a commodity. Currently, the majority of hydrogen (H2) is produced from fossil fuels, but from an environmental perspective, sustainable H2 production should be considered. One of the possible ways of hydrogen production is through fermentation, in particular, at elevated temperature, i.

Reassessment of hydrogen tolerance in Caldicellulosiruptor saccharolyticus.

Background: Caldicellulosiruptor saccharolyticus has the ability to produce hydrogen (H2) at high yields from a wide spectrum of carbon sources, and has therefore gained industrial interest. For a cost-effective biohydrogen process, the ability of an organism to tolerate high partial pressures of H2 (PH2) is a critical aspect to eliminate the need for continuous stripping of the produced H2 from the bioreactor.

Results: Herein, we demonstrate that, under given conditions, growth and H2 production in C.