ELECTROEXTRACTION · Protein electroextraction coupled to direct sorption – a new route for primary recovery of intracellular bioproducts from industrial yeast

This project proposes a new -highly efficient- method for intracellular protein recovery form yeast – electroextraction. Moreover, a novel bio processing strategy will be developed based on its combination with subsequent direct product capture onto a suitable solid phase. Selective recovery of the yeast intracellular soluble proteome will be attempted by permeabilization of cell envelope with high intensity electric field pulses. This treatment as already shown in laboratory experiments leads to a selective release of soluble cytoplasmic proteins, without cell disintegration and with high product yields. The electropermeabilization will be performed in continuous mode under conditions allowing greater selectivity for the targeted species, and limited protease release to avoid product damage. The method will be tested employing several types of commercially relevant yeasts. Sorption is a proven method for efficient product recovery from fermentation liquors or disrupted biomass. The compatibility of the electrically treated feedstock with commercial beaded adsorbents for direct product capture will be assessed, under real process conditions. Operational windows will be defined to allow for product sorption in stirred tank or fluidized bed contactors. Mass transfer properties of the whole system will be explored. Better utilization of total adsorbent ligand sites is expected since less potential interfering substances (nucleic acids, organelles, cell debris) will be liberated. Therefore, a powerful technology for intracellular protein recovery and purification can be envisioned by coupling electroextraction and immediate soluble product sequestration onto a suitable solid phase. ‘Electroextraction’ will provide a route for more facile, efficient, and economical processing of intracellular bioproducts from yeast fermentations that are valuable for the chemical, food, and pharmaceutical industries.