Xylosyltransferase are transferase

Transferase

In biochemistry, a transferase is an enzyme that catalyzes the transfer of a functional group from one molecule to another . For example, an enzyme that catalyzed this reaction would be a transferase:In this example, A would be the donor, and B would be the acceptor...

 enzymes which act upon xylose

Xylose

Xylose is a sugar first isolated from wood, and named for it. Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes an aldehyde functional group. It is the precursor to hemicellulose, one of the main constituents of biomass...

 and are classified under EC 2.4.2.

More specifically, they can refer to:

• Dolichyl-phosphate D-xylosyltransferase
  Dolichyl-phosphate D-xylosyltransferase
  In enzymology, a dolichyl-phosphate D-xylosyltransferase is an enzyme that catalyzes the chemical reactionThus, the two substrates of this enzyme are UDP-D-xylose and dolichyl phosphate, whereas its two products are UDP and dolichyl D-xylosyl phosphate....
  
  
• Dolichyl-xylosyl-phosphate-protein xylosyltransferase
  Dolichyl-xylosyl-phosphate-protein xylosyltransferase
  In enzymology, a dolichyl-xylosyl-phosphate-protein xylosyltransferase is an enzyme that catalyzes the chemical reactionThus, the two substrates of this enzyme are dolichyl D-xylosyl phosphate and protein, whereas its two products are dolichyl phosphate and D-xylosylprotein.This enzyme belongs to...
  
  
• Flavonol-3-O-glycoside xylosyltransferase
  Flavonol-3-O-glycoside xylosyltransferase
  In enzymology, a flavonol-3-O-glycoside xylosyltransferase is an enzyme that catalyzes the chemical reactionThus, the two substrates of this enzyme are UDP-D-xylose and flavonol 3-O-glycoside, whereas its two products are UDP and flavonol 3-[-D-xylosyl--beta-D-glycoside].This enzyme belongs to the...
  
  
• Glycoprotein 2-beta-D-xylosyltransferase
• Protein xylosyltransferase
  Protein xylosyltransferase
  In enzymology, a protein xylosyltransferase is an enzyme that catalyzes the chemical reaction in which a beta-D-xylosyl residue is transferred from UDP-D-xylose to the sidechain oxygen atom of a serine residue in a protein....
  
  
• Xyloglucan 6-xylosyltransferase
  Xyloglucan 6-xylosyltransferase
  In enzymology, a xyloglucan 6-xylosyltransferase is an enzyme that catalyzes the chemical reaction in which an alpha-D-xylosyl residue is transferred from UDP-D-xylose to a glucose residue in xyloglucan, being attached by an alpha-1,6-D-xylosyl-D-glucose bond....
  
  
• XYLT1
  XYLT1
  Xylosyltransferase 1 is an enzyme that in humans is encoded by the XYLT1 gene.-Further reading:...
  
  
• XYLT2
  XYLT2
  Xylosyltransferase 2 is an enzyme that in humans is encoded by the XYLT2 gene.-Further reading:...
  
  
• Zeatin O-beta-D-xylosyltransferase
  Zeatin O-beta-D-xylosyltransferase
  In enzymology, a zeatin O-beta-D-xylosyltransferase is an enzyme that catalyzes the chemical reactionThus, the two substrates of this enzyme are UDP-D-xylose and zeatin, whereas its two products are UDP and O-beta-D-xylosylzeatin....
  
  

xylosyl transferase is the first enzyme involved in the biosynthesis of glycosaminoglycan chains, an important constituent of proteoglycans. There are two types of xylosyl transferases type I and type II.