Literature summary for 2.4.2.26 extracted from

Condac, E.; Dale, G.L.; Bender-Neal, D.; Ferencz, B.; Towner, R.; Hinsdale, M.E.
Xylosyltransferase II is a significant contributor of circulating xylosyltransferase levels and platelets constitute an important source of xylosyltransferase in serum (2009), Glycobiology, 19, 829-833.

Activating Compound

Activating Compound	Comment	Organism	Structure
additional information	unactivated platelets harbor significant XylT activity that is released upon activation with thrombin. Diseases affecting platelet activation may alter serum total XylT activity. In vivo liver cells may contribute significant XylT activity to circulating levels	Homo sapiens

Application

Application	Comment	Organism
medicine	serum XylT levels may be an informative biomarker in patients who suffer from diseases affecting platelet and/or liver homeostasis	Homo sapiens

Cloned(Commentary)

Cloned (Comment)	Organism
c-Myc/TGFalpha doubly transgenic mice. Modified minigene Xylt2 expression construct producing a protein lacking the 45 N-terminal amino acids including the transmembrane domains. The Xylt1 expression cassette producing a protein that lacks 94 N-terminal amino acids including the transmembrane domain which is predicted as for XylT2. Both Xylt1 and Xylt2 expression cassettes cloned into a modified pcDNA3.1 vector containing a transferrin signal peptide and an HPC4 epitope tag in frame on the N-terminus	Mus musculus

Cloned (Comment)

Organism

c-Myc/TGFalpha doubly transgenic mice. Modified minigene Xylt2 expression construct producing a protein lacking the 45 N-terminal amino acids including the transmembrane domains. The Xylt1 expression cassette producing a protein that lacks 94 N-terminal amino acids including the transmembrane domain which is predicted as for XylT2. Both Xylt1 and Xylt2 expression cassettes cloned into a modified pcDNA3.1 vector containing a transferrin signal peptide and an HPC4 epitope tag in frame on the N-terminus

Mus musculus

Inhibitors

Inhibitors	Comment	Organism	Structure
additional information	reduced total XylT activity in sera from mice possessing visible tumors as compared to controls	Mus musculus

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism
0.01172	-	QEEEGSGGGQKK	in Xylt2	Mus musculus
0.02048	-	QEEEGSGGGQKK	in Xylt1	Mus musculus
0.2132	-	TENEGSGLTNIK	in Xylt1	Mus musculus
0.3905	-	TENEGSGLTNIK	in Xylt2	Mus musculus

Organism

Organism	UniProt	Comment	Textmining
Homo sapiens	-	-	-
Mus musculus	-	-	-

Source Tissue

Source Tissue	Comment	Organism	Textmining
blood plasma	-	Homo sapiens	-
blood plasma	XylT levels in plasma are approximately 200% lower than those in serum due in part to XylT released by platelets during blood clotting in vitro. In Xylt2+/+ mice, total serum XylT activity is 42% higher than in plasma. In Xylt2-/- mice, no significant difference between serum and plasma total XylT activity	Mus musculus	-
blood platelet	unactivated platelets harbor significant XylT activity that is released upon activation with thrombin	Homo sapiens	-
blood serum	XylT2 is predominant	Homo sapiens	-
blood serum	XylT2 is predominant. XylT levels in serum are approximately 200% higher than those in plasma due in part to XylT released by platelets during blood clotting in vitro. In Xylt2+/+ mice, total serum XylT activity is 42% higher than in plasma. In Xylt2-/- mice, no significant difference between serum and plasma total XylT activity	Mus musculus	-
Hep-G2 cell	-	Homo sapiens	-
liver	liver is a significant source of circulating XylT2 activity	Mus musculus	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.
UDP-D-xylose + QEEEGSGGGQKK	QEEEGSGGGQKK is a better acceptor substrate than TENEGSGLTNIK	Mus musculus	UDP + QEEEG-(D-xylosyl)SGGGQKK	-	?
UDP-D-xylose + QEEEGSGGGQKK	the bikunin nuclear acceptor peptide QEEEGSGGGQKK is not a differential acceptor substrate for the human XylT isoenzymes but is a good acceptor substrate for total XylT activity measurements	Homo sapiens	UDP + QEEEG-(D-xylosyl)SGGGQKK	-	?
UDP-D-xylose + TENEGSGLTNIK	QEEEGSGGGQKK is a better acceptor substrate than TENEGSGLTNIK	Mus musculus	UDP + TENEG-(D-xylosyl)SGLTNIK	-	?
UDP-D-xylose + TENEGSGLTNIK	the 3-A4-amyloid protein precursor protein peptide TENEGSGLTNIK is an acceptor substrate for XylT1	Homo sapiens	UDP + TENEG-(D-xylosyl)SGLTNIK	-	?

Synonyms

Synonyms	Comment	Organism
xylosyltransferase I	-	Mus musculus
xylosyltransferase I	-	Homo sapiens
xylosyltransferase II	-	Mus musculus
xylosyltransferase II	-	Homo sapiens
XYLT1	-	Mus musculus
XYLT1	-	Homo sapiens
XYLT2	-	Mus musculus
XYLT2	-	Homo sapiens

General Information

General Information	Comment	Organism
physiological function	in Xylt2-/- mice total XylT activity is decreased ca. 99% as compared to Xylt2+/+ mice	Mus musculus