A system and a method for the production of recombinant N-glycosylated targetproteins. The system comprises a prokaryotic organism (e.g. Escherichia coli)into which is introduced a genetic information encoding for a metabolicapparatus capable of carrying out the requested N-glycosylation of the targetprotein. Said prokaryotic organism also contains the genetic informationrequired for the expression of one or more recombinant target proteins. Themetabolic apparatus preferably comprises specific glycosyltransferases for theassembly of the oligosaccharide on a lipid carrier and an OTase thatcovalently links this oligosaccharide to specific residues of the desiredprotein.
