PGM2 proves positive in biofuel testing

Biofuel testing undertaken at Lund University, Sweden, has examined the impact of the PGM2 gene and a combination method of improving xylose utilisation in the processing of lignocellulosic biomass to create bioethanol.

The latter method consists of overexpression of genes which encode xylulokinase, deletion of the GRE3 gene in engineered strains of the brewer's yeast Saccharomyces cerevisiae and the presence of non-oxidative pentose phosphate pathway enzymes.

Engineered S cerevisiae was created following the discovery that xylose sugars - which form a significant part of lignocellulosic biomass - are not naturally fermented by the microorganism.

However, the biofuel testing revealed that the method can impair galactose fermentation if PGM2 is not overexpressed.

By overexpressing the gene, this impairment is removed, while it is itself associated with improved fermentation of both galactose and xylose sugars in the lignocellulosic feedstock.

The findings are published in Biotechnology for Biofuels, an open-access, peer-reviewed journal addressing the advances in operational and technological processes made in biomass-to-biofuel conversion.