Master-Stroke by Researchers Yields One-Step Super Yeast for Cellulosic Ethanol

Japanese researchers have succeeded in integrating cellulolytic enzyme genes from koji mould, into a sake yeast. This yeast now has the the cellulolytic enzyme prominently sprinkled over its cell membrane, where it can break down cellulose from biomass, while the sake yeast itself ferments the resulting simple sugars into ethanol.

To create the super yeast that produces the bioethanol, koji mold genes that produce cellulolytic enzymes were integrated into sake yeast using cell surface engineering so that the enzymes are densely displayed on the surfaces of the yeast cells. Because super yeast combines the capabilities of koji mold, which converts the cellulose starch (cellooligosaccharide) into sugar (glucose), with that of yeast, which ferments sugar (glucose), it can produce ethanol by itself from cellulose pretreated with subcritical water

The combination of subcritical water treatment with super yeast enables clean and easy pretreatment, and simple and efficient ethanol production, which means that small-scale plants could be built and operated in many different rural locations where the plant materials are produced.

Gekkeikan Research Institute has already demonstrated at the experimental level that the new process can effectively produce ethanol from paddy straw and chaff, and it is now working to refine the process for commercial production through research aimed at boosting alcohol yield and integration with various other technologies. _Gekkeikan_via_Japanfs_via_autobloggreen

This one step process utilising a hybrid yeast w/mould genes, is just the beginning of the clever use of biotechnology for meeting the basic needs of human society. Consider it a humble, though important, beginning.