Novel beta-galactoside-alpha2,3-sialyltransferase, a gene encoding thereof, and a method for producing thereof

An isolated protein having β-galactoside-α2,3-sialyltransferase activity, which comprises an amino acid sequence comprising conservative substitution of one or more amino acids in, and sharing an amino homology of at least 90% or more with, an amino acid sequence selected from SEQ ID NO:

• 31, or amino acid residues 23-402 of SEQ ID NO:
• 31.

An isolated protein having β-galactoside-α2,3-sialyltransferase activity, which comprises an amino acid sequence sharing an amino acid homology of at least 90% or more with an amino acid sequence selected from SEQ ID NO:

• 31, or amino acid residues 23-402 of SEQ ID NO:
• 31.

An isolated protein having β-galactoside-α2,3-sialyltransferase activity, which is encoded by a nucleic acid comprising a nucleotide sequence selected from SEQ ID NO:

• 30, or nucleotides 67-1209 of SEQ ID NO:
• 30.

An isolated protein having β-galactoside-α2,3-sialyltransferase activity, which is encoded by a nucleic acid comprising a nucleotide sequence hybridizable under conditions including hybridization at 65° C. in 0.5M sodium phosphate pH7.2, 1 mM EDTA, 7% SDS, 1% BSA, and washing at 65° C. in 40 mM sodium phosphate buffer pH 7.2, 1 mM EDTA, 5% SDS, 0.5% BSA and at 65° C. in 40 mM sodium phosphate buffer pH 7.2, 1 mM EDTA, 1% SDS, with the full length complementary stand of a nucleotide sequence of SEQ ID NO:

• 30.

An isolated nucleic acid encoding a protein comprising an amino acid sequence selected from SEQ ID NO:

• 31 or amino acid residues 23-402 of SEQ ID NO:
• 31.

An isolated nucleic acid encoding a protein having β-galactoside-α2,3-sialyltransferase activity, wherein the protein comprises an amino acid sequence comprising conservative substitution of one or more amino acids in, and sharing an amino acid homology of at least 90% or more with, an amino acid sequence selected from SEQ ID NO:

• 31 or amino acid residues 23-402 of SEQ ID NO:
• 31.

An isolated nucleic acid encoding a protein having β-galactoside-α2,3-sialyltransferase activity, wherein the protein comprises an amino acid sequence sharing a homology of at least 90% with an amino acid sequence selected from SEQ ID NO:

• 31 or amino acid residues 23-402 of SEQ ID NO:
• 31.

An isolated nucleic acid comprising a nucleotide sequence selected from SEQ ID NO:

• 30 or nucleotides 67-1209 of SEQ ID NO:
• 30.

An isolated nucleic acid encoding a protein having β-galactoside-α2,3-sialyltransferase activity, wherein the nucleic acid comprises a nucleotide sequence hybridizable under conditions including hybridization at 65° C. in 0.5M sodium phosphate pH7.2, 1 mM EDTA, 7% SDS, 1% BSA, and washing at 65° C. in 40 mM sodium phosphate buffer pH 7.2, 1 mM EDTA, 5% SDS, 0.5% BSA and at 65° C. in 40 mM sodium phosphate buffer pH 7.2, 1 mM EDTA, 1% SDS, with the full length complementary stand of a nucleotide sequence of SEQ ID NO:

• 30.