Patent ID: 6534315
Filing Date: 2003-03-18
Classification: C12N

Abstract:
A DNA cassette intended for the transformation of a yeast host strain comprisingat least one excision module comprising: one negative dominant selectable marker; two direct repeat sequences (DRS), the length of which is at least 30 basepairs (bp), wherein said DRS do not contain exogenous DNA and are non recombinogenic: with the genome of the yeast host strain, wherein the two direct repeat sequences flank a fragment comprising said negative dominant selectable marker and wherein the two DRS comprise (a) mosaic sequences comprising an assembly of fragments of various DNA sequences of a yeast strain belonging to the same genus as said yeast host strain or (b) one or more DNA sequence(s) not present in the yeast host strain, but present in other strains belonging to the same genus of said yeast host strain; and at least one rare restriction site at each end of said excision module.