Species: Bos taurus
A unique O-glycan structure, the trisaccharide Xylα1-3Xylα1-3Glcβ1-O-Ser, is found on the consensus sequence C-X-S-X-P-C (X stands for any amino acid) in epidermal growth factor (EGF)-like domains of plasma proteins such as clotting factor VII and clotting factor IX (see Xyl-α(1-3)-Xyl-α(1-3)-Glc-β-EGF-like domain) [Omichi97].
One of the enzymes involved in catalyzing the biosynthesis of this trisaccharide, UDP-D-xylose:β-D-glucoside α-1,3-D-xylosyltransferase, has been purified from the microsomal fraction of bovine liver [Ishimizu07]. The best acceptor substrate of those tested was the EGF-like domain of bovine factor IX carrying beta-glucoside at Ser53.
Upon purification a second active peak wht molecular weight of 124 kDa was also observed. This peak was thought to represent a dimer of the protein [Ishimizu07].
Molecular Weight of Polypeptide: 52.0 kD (experimental) [Ishimizu07]
Enzymatic reaction of: UDP-D-xylose:β-D-glucoside α-1,3-D-xylosyltransferase
EC Number: 18.104.22.168UDP-α-D-xylose + Glc-β-EGF-like domain ⇄ UDP + Xyl-α(1-3)-Glc-β-EGF-like domain
The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the Enzyme Commission system.
Reversibility of this reaction is unspecified.Co2+ [Ishimizu07], Cu2+ [Ishimizu07], Fe2+ [Ishimizu07], Ni2+ [Ishimizu07]Kinetic Parameters:
pH(opt): 7 [Ishimizu07]
Ishimizu07: Ishimizu T, Sano K, Uchida T, Teshima H, Omichi K, Hojo H, Nakahara Y, Hase S (2007). "Purification and substrate specificity of UDP-D-xylose:beta-D-glucoside alpha-1,3-D-xylosyltransferase involved in the biosynthesis of the Xyl alpha1-3Xyl alpha1-3Glc beta1-O-Ser on epidermal growth factor-like domains." J Biochem 141(4);593-600. PMID: 17317689
Omichi97: Omichi K, Aoki K, Minamida S, Hase S (1997). "Presence of UDP-D-xylose: beta-D-glucoside alpha-1,3-D-xylosyltransferase involved in the biosynthesis of the Xyl alpha 1-3Glc beta-Ser structure of glycoproteins in the human hepatoma cell line HepG2." Eur J Biochem 245(1);143-6. PMID: 9128735
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