Patent ID: 7273754

Claim:
An expression system comprising: an isolated host cell comprising: a first expressible recombinant polynucleotide which encodes a human core 1 β3-galactosyl transferase; and a second expressible recombinant polynucleotide which encodes a human core 1 β3-galactosyl transferase specific molecular chaperone for expressing the active form of the human core 1 β3-galactosyl transferase, wherein the second expressible recombinant polynucleotide comprises: (A) a polynucleotide having the sequence of SEQ ID NO: 2; (B) a polynucleotide encoding the polypeptide of SEQ ID NO: 1; or (C) a polynucleotide which differs in nucleotide sequence from the polynucleotides of (A) or (B) in that said polynucleotide lacks a nucleotide sequence which encodes a transmembrane domain wherein the human core 1 β3-galactosyl transferase specific molecular chaperone is soluble.