This invention provides recombinant glycosyltransferase fusion proteins having a desired level of expression and enzymatic activity (for example, acceptor substrate specificity or catalytic activity). The fusion proteins of the invention have a functional domain of a first glycosyltransferase joined, directly or through a peptide linker, to a subsequence of a functional domain of a second glycosyltransferase. Nucleic acids that encode the fusion proteins are also provided, as are host cells for expressing the fusion proteins and methods of making and using the fusion proteins of the invention.