WITHDRAWN: Impact of overexpressed secretory-pathway genes on the secretion of IFNgamma in Hansenula polymorpha applying an rDNA-cointegration approach for assessment.

gamma-Interferon (IFNgamma) is poorly secreted from recombinant Hansenula polymorpha cells in the form of hyperglycosylated molecules. A selection of four secretory-pathway genes was assessed for possible impact on secretion improvements. For assessment, rDNA integration vectors harbouring the H. polymorpha-derived KAR2, PDI, SSO2 or CNE1 gene were co-integrated along with the IFNgamma-integration/expression vector. Overexpression of CNE1 resulted in an increased secretion of the cytokine, predominantly consisting of molecules of distinct size. Deglycosylation with PGNaseF resulted in an M(r) reduction of the secreted IFNgamma corresponding to the removal of two N-linked glycoside chains. Coexpression of KAR2, PDI or SSO2 exhibited no effect.