| abstract |
The present invention discloses a transformation system useful to express heterologous proteins in the Candida utilis yeast, based on obtaining auxotrophic mutants of said species as well as the isolation of different genes, from a genomic library, which complement said auxotrophies. The transformation system uses as hosts new auxotrophic mutants obtained from the yeast NRRL Y-1084 of Candida utilis which are defective mainly in the biosynthetic ways of uracyl and histidine, which are transformed with plasmids containing as selection markers the genes URA3 and HIS3 of Candida utilis. Another aspect of the invention is the isolation of the gene coding for the enzyme sucrose invertase or β-fructofuranosidase of Candida utilis, as well as the identification of sequences for promoting, secretion signalling and termination of said gene INV1. These sequences are useful to obtain the expression of heterologous proteins in said yeast. |