Patent ID: 8338154

Claim:
A mutant sialyltransferase-I (SAT-I) comprising the amino acid sequence of SEQ ID NO:4 into which at least one amino acid substitution selected from the group consisting of (a) to (d) shown below has been introduced: (a) substitution of Asn by Lys in the amino acid sequence motif (i) Asn Glu Ser (amino acids 224-226 of SEQ ID NO:4); (b) substitution of Thr by Gln in the amino acid sequence motif (ii) Asn Val Thr (amino acids 334-336 of SEQ ID NO:4); (c) substitution of Asn by Ser in the amino acid sequence motif (iii) His Val Gly Asn Lys Thr (SEQ ID NO: 43) (amino acids 177-182 of SEQ ID NO:4); and (d) substitution of His by Asp in the amino acid sequence motif (iii) His Val Gly Asn Lys Thr (SEQ ID NO: 43) (amino acids 177-182 of SEQ ID NO:4).