Efficient cell-free hydrogen production

Abstract

Cell-free synthesis of hydrogen from glucose and cellulosic hydrolysates is provided. Bacterial cells are modified to express high levels of (i) active [FeFe] hydrogenase; (ii) ferredoxin; and (iii) ferredoxin-NADP-reductase (FNR). The cells are then lysed and the lysate is combined with substrate during a production phase, where His produced. The substrate is typically a sugar, e.g. glucose, cellulose hydrolysates, fructose, and the like, including pentose sugars capable of entering the bacterial pentose phosphate cycle. The reaction mixture may be further supplemented with one or more of niacin as a precursor to nicotinamide; a nuclease, particularly a ribonuclease, to break down nucleic acids and generate adenine; and iodoacetamide to inactivate the normal cellular glycolytic pathway and thus maximize conversion yields.