IMPROVED PRODUCTION OF SPHINGOID BASES USING GENETICALLY ENGINEERED MICROBIAL STRAINS

摘要

The present invention provides genetically engineered microbial strains, in particular genetically engineered yeast strains, that produce at least 0.5 mg per g CDW of a sphingoid base according to Formula I or a salt or ester thereof. The present invention provides a method to obtain genetically engineered microbial strains producing at least 0.5 mg per g CDW of a sphingoid base according to Formula I or a salt or ester thereof. The method comprises the steps of: a) increasing the expression of a polynucleotide encoding an enzyme having ceramide synthase activity and/or an enzyme having ceramidase activity, the latter being capable of preferentially, or even specifically, hydrolyzing ceramides containing a sphingoid base according to Formula I, and/or b) decreasing the expression of a polynucleotide encoding an enzyme having sphingolipid ?8-desaturase activity and/or an enzyme having ceramidase activity, the latter being capable of preferentially, or even specifically, hydrolyzing ceramides containing phytosphingosine or dihydrosphingosine as sphingoid base, and isolating strains with the required productivity.