HETEROLOGOUS KLUYVEROMYCES-LACTIS BETA-GALACTOSIDASE PRODUCTION AND RELEASE BY SACCHAROMYCES-CEREVISIAE OSMOTIC-REMEDIAL THERMOSENSITIVE AUTOLYTIC MUTANTS

The beta-galactosidase from Kluyveromyces lactis is a high molecular w eight protein with commercial interest. A major drawback of its indust rial production is the high cost associated with extraction and downst ream processing due to its intracellular nature. In this work, the eff ectiveness of the utilization of Saccharomyces cerevisiae LD1 and LHDP 1 strains, osmotic-remedial mutants which lyse at 37 degrees C, for th e heterologous production and release into the extracellular medium of this protein has been proved. The highest absolute values of released beta-galactosidase have been obtained with the protease-deficient str ain LHDP1 by osmotic shock.