Engineered autolytic yeast strains secreting Kluyveromyces lactis beta-galactosidase for production of heterologous proteins in lactose media.
Secretion of the heterologous Kluyveromyces lactis beta-galactosidase into culture medium by several Saccharomyces cerevisiae osmotic-remedial thermosensitive-autolytic mutants was assayed and proved that new metabolic abilities were conferred since the constructed strains were able to grow in lactose-containing media. Cell growth became independent of a lactose-uptake mechanism. Higher levels of extra-cellular and intra-cellular beta-galactosidase production, lactose consumption and growth were obtained with the LHDP1 strain, showing a thermosensitive-autolytic phenotype as well as being peptidase-defective. The recombinant strain LHDP1 presented the highest beta-galactosidase yields from biomass and the lowest ethanol levels from lactose. This strain is effective for the heterologous production and release of K. lactis beta-galactosidase into the extra-cellular medium after osmotic shock.
Becerra
Manuel
M
Departamento de Bioloxía Celular e Molecular, Facultade de Ciencias, Universidade da Coruña, Campus da Zapateira s/n, 15071-A Coruña, Spain. manu@udc.es
Rodríguez-Belmonte
Esther
E
Esperanza Cerdán
M
M
González Siso
M Isabel
MI
D002611:Cheese / Q000382:microbiology; D000431:Ethanol / Q000378:metabolism; D005818:Genetic Engineering; D007716:Kluyveromyces / Q000201:enzymology* / Q000235:genetics; D007785:Lactose / Q000378:metabolism; D009995:Osmosis; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D001616:beta-Galactosidase / Q000096:biosynthesis* / Q000235:genetics
D011994:Recombinant Proteins; D000431:Ethanol; D001616:beta-Galactosidase; D007785:Lactose