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Details on Person UniProt:P16442 ABO

Class:IdReferenceGeneProduct:50808
_chainChangeLogchain:1-354 added on Fri February 6 2015;chain:54-354 added on Fri February 6 2015
_displayNameUniProt:P16442 ABO
_timestamp2026-02-20 21:57:03
chainchain:1-354
chain:54-354
checksumA03DA16E630C1608
commentFUNCTION This protein is the basis of the ABO blood group system. The histo-blood group ABO involves three carbohydrate antigens: A, B, and H. A, B, and AB individuals express a glycosyltransferase activity that converts the H antigen to the A antigen (by addition of N-acetyl-alpha-D-galactosamine (GalNAc)) or to the B antigen (by addition of galactose (Gal)), whereas O individuals lack such activity and express the H antigen precursor unmodified.FUNCTION Catalyzes the transfer of GalNAc or Gal in an alpha1,3 linkage to the terminal Gal of all five types of naturally occurring H antigens, forming the antigenic structures of the A and B blood groups.CATALYTIC ACTIVITY an alpha-L-fucosyl-(1->2)-beta-D-galactosyl derivative + UDP-N-acetyl-alpha-D-galactosamine = an N-acetyl-alpha-D-galactosaminyl-(1->3)-[alpha-L-fucosyl-(1->2)]-beta-D-galactosyl derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-fucosyl-(1->2)-beta-D-galactosyl derivative + UDP-alpha-D-galactose = an alpha-D-galactosyl-(1->3)-[alpha-L-fucosyl-(1->2)]-beta-D-galactosyl derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->3)-beta-D-GlcNAc derivative + UDP-N-acetyl-alpha-D-galactosamine = an alpha-D-GalNAc-(1->3)-[alpha-L-Fuc-(1->2)]-beta-D-Gal-(1->3)-beta-D-GlcNAc derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->4)-beta-D-GlcNAc derivative + UDP-N-acetyl-alpha-D-galactosamine = an alpha-D-GalNAc-(1->3)-[alpha-L-Fuc-(1->2)]-beta-D-Gal-(1->4)-beta-D-GlcNAc derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->3)-beta-D-GlcNAc derivative + UDP-alpha-D-galactose = an alpha-D-Gal-(1->3)-[alpha-L-Fuc-(1->2)]-beta-D-Gal-(1->3)-beta-D-GlcNAc derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->4)-beta-D-GlcNAc derivative + UDP-alpha-D-galactose = an alpha-D-Gal-(1->3)-[alpha-L-Fuc-(1->2)]-beta-D-Gal-(1->4)-beta-D-GlcNAc derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->3)-alpha-D-GalNAc derivative + UDP-alpha-D-galactose = an alpha-D-Gal-(1->3)-[alpha-L-Fuc-(1->2)]-beta-D-Gal-(1->3)-alpha-D-GalNAc derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->3)-beta-D-GalNAc derivative + UDP-alpha-D-galactose = an alpha-D-Gal-(1->3)-[alpha-L-Fuc-(1->2)]-beta-D-Gal-(1->3)-beta-D-GalNAc derivative + UDP + H(+)CATALYTIC ACTIVITY an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->4)-beta-D-Glc derivative + UDP-alpha-D-galactose = an alpha-D-Gal-(1->3)-[alpha-L-Fuc-(1->2)]-beta-D-Gal-(1->4)-beta-D-Glc derivative + UDP + H(+)COFACTOR Binds 1 Mn(2+) ion per subunit.BIOPHYSICOCHEMICAL PROPERTIES kcat is 1.3 sec(-1) for type I H-antigen (A transferase) (PubMed:16326711). kcat is 0.5 sec(-1) for type I H-antigen (B transferase) (PubMed:16326711). kcat is 1.8 sec(-1) for type II H-antigen (A transferase) (PubMed:16326711). kcat is 1.2 sec(-1) for type II H-antigen (B transferase) (PubMed:16326711).PATHWAY Protein modification; protein glycosylation.SUBCELLULAR LOCATION Membrane-bound form in trans cisternae of Golgi. Secreted into the body fluid.TISSUE SPECIFICITY Expressed at high levels in testis. Also expressed in pancreas, uterus and lung and salivary gland.DOMAIN The conserved DXD motif is involved in cofactor binding. The manganese ion interacts with the beta-phosphate group of UDP and may also have a role in catalysis.PTM The soluble form derives from the membrane form by proteolytic processing.POLYMORPHISM Genetic variations in ABO define the ABO blood group system [MIM:616093]. The ABO blood group system is one of the most important blood group systems in transfusion medicine. The ABO blood group involves 3 carbohydrate antigens: A, B, and H. A, B, and AB individuals express a glycosyltransferase activity that converts the H antigen to the A antigen (by addition of GalNAc) or to the B antigen (by addition of Gal). There are only 4 amino acid differences between A and B transferases in the catalytic domain, two of which (Leu266Met and Gly268Ala) are primarily responsible for the substrate specificity. The group O phenotype results from variations in ABO that cause a loss of glycosyltransferase activity. The most common group O allele results from a single nucleotide deletion near the 5' end of the gene (NM_020469.2:c.261del) that causes a frameshift and early termination with no active enzyme production (p.Thr88Profs*31). The sequence shown is that of ABO*A1.01.SIMILARITY Belongs to the glycosyltransferase 6 family.ONLINE INFORMATION Histo-blood group ABO system transferaseONLINE INFORMATION Histo-blood group ABO system transferase
descriptionrecommendedName: Histo-blood group ABO system transferase alternativeName: Fucosylglycoprotein 3-alpha-galactosyltransferase alternativeName: Fucosylglycoprotein alpha-N-acetylgalactosaminyltransferase alternativeName: Glycoprotein-fucosylgalactoside alpha-N-acetylgalactosaminyltransferase ecNumber evidence="4 13"2.4.1.40 alternativeName: Glycoprotein-fucosylgalactoside alpha-galactosyltransferase ecNumber evidence="4 13"2.4.1.37 alternativeName: Histo-blood group A transferase shortName: A transferase shortName evidence="23"GTA alternativeName: Histo-blood group B transferase shortName: B transferase shortName evidence="23"GTB alternativeName: NAGAT component recommendedName: Fucosylglycoprotein alpha-N-acetylgalactosaminyltransferase soluble form /component
geneNameABO
identifierP16442
isSequenceChangedFALSE
keyword3D-structure
Blood group antigen
Direct protein sequencing
Glycoprotein
Glycosyltransferase
Golgi apparatus
Manganese
Membrane
Metal-binding
Proteomics identification
Reference proteome
Secreted
Signal-anchor
Transferase
Transmembrane
Transmembrane helix
modified[InstanceEdit:84067] Schmidt, EE, 2003-12-18 04:29:09
[InstanceEdit:143527] Schmidt, EE, 2004-11-12 07:45:10
[InstanceEdit:217385] Schmidt, EE, 2008-03-27 06:23:53
[InstanceEdit:354386] Schmidt, EE, 2008-06-18 04:45:12
[InstanceEdit:384350] Kanapin, AA, 2008-11-26 14:00:39
[InstanceEdit:392885] Kanapin, AA, 2009-03-09 12:07:18
[InstanceEdit:400710] Schmidt, EE, 2009-03-25 05:33:35
[InstanceEdit:423310] Kanapin, AA
[InstanceEdit:435478] Kanapin, AA
[InstanceEdit:435871] Kanapin, AA
[InstanceEdit:447347] Kanapin, AA
[InstanceEdit:525883] Kanapin, AA
[InstanceEdit:613449] Kanapin, AA
[InstanceEdit:797602] Kanapin, AA
[InstanceEdit:937368] Yung, CK
[InstanceEdit:1042053] Yung, CK
[InstanceEdit:1220657] Yung, CK
[InstanceEdit:1300696] Yung, CK
[InstanceEdit:1301627] Yung, CK
[InstanceEdit:1551960] Weiser, JD
[InstanceEdit:1995863] Weiser, JD
[InstanceEdit:2132304] Weiser, JD
[InstanceEdit:2265580] Weiser, JD
[InstanceEdit:2587579] Weiser, JD
[InstanceEdit:3132113] Weiser, JD
[InstanceEdit:5433710] Weiser, JD
[InstanceEdit:5618415] Weiser, JD
[InstanceEdit:5634237] Weiser, JD
[InstanceEdit:5673015] Weiser, JD
[InstanceEdit:5691543] Weiser, JD
[InstanceEdit:8856987] Weiser, JD
[InstanceEdit:9037114] Weiser, JD
[InstanceEdit:9607352] Weiser, JD
[InstanceEdit:9637257] Weiser, JD
[InstanceEdit:9676415] Weiser, JD
[InstanceEdit:9715482] Weiser, JD
[InstanceEdit:9730071] Weiser, JD
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
[InstanceEdit:9983091] Weiser, Joel, 2026-02-20
nameABO
referenceDatabase[ReferenceDatabase:2] UniProt
secondaryIdentifierBGAT_HUMAN
B0JDB9
O14758
Q14490
Q53I57
Q6ISD4
Q6KFZ2
Q70V27
Q99484
Q99485
Q9NY01
Q9UQ68
Q9UQ69
sequenceLength354
species[Species:48887] Homo sapiens
(referenceEntity)[EntityWithAccessionedSequence:9034057] ABO-A [Golgi membrane] [Homo sapiens]
[EntityWithAccessionedSequence:9034064] ABO-B [Golgi membrane] [Homo sapiens]
[EntityWithAccessionedSequence:9034076] sABO-B [extracellular region] [Homo sapiens]
[EntityWithAccessionedSequence:9034078] sABO-A [extracellular region] [Homo sapiens]
(referenceSequence)[ReplacedResidue:9034032] L-arginine 176 replaced with glycine
[ReplacedResidue:9034040] glycine 268 replaced with L-alanine
[ReplacedResidue:9034050] glycine 235 replaced with L-serine
[ReplacedResidue:9034071] L-leucine 266 replaced with L-methionine
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No pathways have been reviewed or authored by UniProt:P16442 ABO (50808)