The lcc1 gene coding for the laccase from Trametes versicolor DSM11269 was cloned into the genome of
Yarrowia lipolytica using either single or multiple integration sites. The levels of the recombinant laccase
activity secreted in the culture media were 0.25 and 1 U ml1 for single and multiple integrations, respectively.
The strain with a single integration was successfully used to express variant libraries which were
screened on ABTS substrate. The strain encoding the double mutant L185P/Q214K (rM4A) showed a sixfold
enhancement in secreted enzyme activity. The catalytic efficiency of the purified rM-4A laccase was
respectively increased 2.4- and 2.8-fold towards ABTS and 2,6-dimethoxyphenol, compared to the rWT.
Culture supernatants containing either rWT or rM-4A catalyzed the almost complete decolorization of an
Amaranth solution (70 nM s1
). Taken together, our results open new perspectives for the use of Y. lipolytica
as a molecular evolution platform to engineer laccases with improved properties.