In order to amend the pCGEN for YRBC, a 2820 bp fragment, covering the URA3 marker and 2 l ori
from plasmid pNEB-hyg-yeast (digested with SacII and SspI) was ligatedin vitro with 8257 bp fragment
of vector pCGEN (digested with SacII and PsiI) resulting in
pCGEN-YR