Use of fungi to make bio-ethanol

Fungi that digest wood in novel ways could fuel new avenues of research on cellulosic ethanol, and suggest a need to move beyond traditional classification systems.

Fungi that digest wood are typically categorized as white rots, which degrade both lignin and cellulose, or brown rots, which only have enzymes that act on cellulose. But two newly sequenced species are capable of digesting lignin, even though they lack the enzymes typically found in white rots, according to a study published recently in PNAS.

The species, Botryobasidium botryosum and Jaapia argillacea, appeared to be white-rot fungi based on the microscopic patterns they created in decomposing wood. However, at the molecular level, researchers found that the key enzymes considered markers of white-rot fungi were missing.

The results suggest a continuum rather than a dichotomy between the white-rot and brown-rot modes of wood decay, and highlight the need for a more nuanced categorization of rot types, according to the authors. Identifying the decay mechanisms in these new species could also have practical applications in the production of cellulosic biofuels.

The research is titled “Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/brown-rot paradigm for wood decay fungi.”

Posted by Tim Sandle