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Summary: The development and advent of mutagenesis tools for solventogenic clostridial species in recent years has allowed for the increased refinement of industrially relevant strains. In this study we have utilised CLEAVE™, a CRISPR/Cas genome editing system developed by Green Biologics Ltd., to engineer a strain of Clostridium saccharoperbutylacetonicum N1‐4(HMT) with potentially useful solvents titres and energy metabolism. As one of two enzymes responsible for the conversion of glyceraldehyde‐3‐phosphate (GAP) to 3‐phosphoglyceric acid in glycolysis, it was hypothesised that deletion of gapN would increase ATP and NADH production that could in turn improve solvent production. Herein, whole genome sequencing has been used to evaluate CLEAVE™ and the successful knockout of gapN, demonstrating a clean knockout with no other detectable variations from the wild type sequence. Elevated solvent levels were detected during the first 24 h of batch fermentation, indicating an earlier shift to solventogenesis. A 2.4‐fold increase in ATP concentration was observed, and quantitation of NAD(P)H derivatives revealed a more reducing cytoplasm for the gapN strain. These findings expand our understanding of clostridium carbon metabolism and report a new approach to optimising biofuel production. [ABSTRACT FROM AUTHOR]

Presents an abstract on optimization of reductive biotransformations of phenylalkene derivatives catalyzed by an enoate reductase from the acetogenic anaerobe Acetobacterium woodii DSM 1030 taken from the Art of Anaerobes Conference on August 15-16, 1996 at Athens, Georgia. How enoate reductases catalyze the stereospecific and regiospecific hydrogenation of carbon-carbon double bonds.