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Information on EC 2.4.1.229 - [Skp1-protein]-hydroxyproline N-acetylglucosaminyltransferase
for references in articles please use BRENDA:EC2.4.1.229
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EC Tree 2 Transferases
2.4 Glycosyltransferases
2.4.1 Hexosyltransferases
2.4.1.229 [Skp1-protein]-hydroxyproline N-acetylglucosaminyltransferase
IUBMB Comments
Skp1 is a cytoplasmic and nuclear protein required for the ubiquitination of cell cycle regulatory proteins and transcriptional factors. In Dictyostelium Skp1 is modified by the linear pentasaccharide Galα1-6Galα1-L-Fucα1-2Galβ1-3GlcNAc, which is attached to a hydroxyproline residue at position 143. This enzyme catalyses the first step in the building up of the pentasaccharide by attaching an N-acetylglucosaminyl group to the hydroxyproline residue. It requires dithiothreitol and a divalent cation for activity.
The enzyme appears in viruses and cellular organisms
Reaction Schemes
showSynonyms
gnt51, hydroxyproline-capping enzyme, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
acetylglucosaminyltransferase, uridine diphosphoacetylglucosamine-glycoprotein serine/threonine
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acetylglucosaminyltransferase, uridine diphosphoacetylglucose-protein Skp1 hydroxyproline
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GnT1
GnT51
hydroxyproline-capping enzyme
Skp1 alpha-GlcNAcT1-like enzyme
Skp1-HyPro GlcNAc-transferase
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UDP-GlcNAc:hydroxyproline polypeptide GlcNAc-transferase
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UDP-GlcNAc:Skp1-hydroxyproline GlcNAc-transferase
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UDP-N-acetylglucosamine (GlcNAc):hydroxyproline polypeptide GlcNAc-transferase
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
UDP-N-acetyl-alpha-D-glucosamine + [Skp1-protein]-trans-4-hydroxy-L-proline = UDP + [Skp1-protein]-O-(N-acetyl-alpha-D-glucosaminyl)-trans-4-hydroxy-L-proline
UDP-N-acetyl-alpha-D-glucosamine + [Skp1-protein]-trans-4-hydroxy-L-proline = UDP + [Skp1-protein]-O-(N-acetyl-alpha-D-glucosaminyl)-trans-4-hydroxy-L-proline
Requires dithiothreitol and a divalent cation for activity. This enzyme commences the building up of a pentasaccharide (Galalpha1-6Galalpha1-L-Fucalpha1-2Galbeta1-3GlcNAc) on Hyp-143 of the Dictyostelium protein Skp1, which is required for the ubiquitination of cell-cycle regulatory proteins and transcription factors. The fucose residue is probably in the alpha configuration. The specificity of the enzyme for Skp1-Hyp-143 and its high affinity for this substrate suggests that it is the GlcNAc-transferase that modifies Skp1 in vivo
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UDP-N-acetyl-alpha-D-glucosamine + [Skp1-protein]-trans-4-hydroxy-L-proline = UDP + [Skp1-protein]-O-(N-acetyl-alpha-D-glucosaminyl)-trans-4-hydroxy-L-proline
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
hexosyl group transfer
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SYSTEMATIC NAME
IUBMB Comments
UDP-N-acetyl-alpha-D-glucosamine:[Skp1-protein]-trans-4-hydroxy-L-proline N-acetyl-alpha-D-glucosaminyl-transferase
Skp1 is a cytoplasmic and nuclear protein required for the ubiquitination of cell cycle regulatory proteins and transcriptional factors. In Dictyostelium Skp1 is modified by the linear pentasaccharide Galalpha1-6Galalpha1-L-Fucalpha1-2Galbeta1-3GlcNAc, which is attached to a hydroxyproline residue at position 143. This enzyme catalyses the first step in the building up of the pentasaccharide by attaching an N-acetylglucosaminyl group to the hydroxyproline residue. It requires dithiothreitol and a divalent cation for activity.
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CAS REGISTRY NUMBER
COMMENTARY
256531-81-4
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37277-59-1
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
UDP-N-acetyl-alpha-D-glucosamine + [Skp1-protein]-trans-4-hydroxy-L-proline
UDP + [Skp1-protein]-O-(N-acetyl-alpha-D-glucosaminyl)-trans-4-hydroxy-L-proline
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Substrates: -
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UDP-N-acetylglucosamine + hydroxyproline-peptide
UDP + (N-acetyl-D-glucosaminyl)hydroxyproline peptide
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Substrates: synthetic peptide substrate
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UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyproline
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
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UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
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UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
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UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
Products: -
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyproline
Substrates: enzyme is involved in O-glycosylation of Skp1-protein and mucin formation
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyproline
Substrates: enzyme is highly specific for the Skp1-protein
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
Substrates: enzyme attaches the first sugar of pentasaccharide chain
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
Substrates: hydroxyproline143
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
Substrates: -
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: -
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: transfer to the hydroxyproline, at the Thr-Pro143 dipeptide, preceded by a coil and succeeded by an alpha-helix in Skp1
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: -
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: transfer to the hydroxyproline, at the Thr-Pro143 dipeptide, preceded by a coil and succeeded by an alpha-helix in Skp1
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: hydroxyproline143
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: high affinity for UDP-GlcNAc
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: recombinant protein substrate, deficient in GlcNAc
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: -
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UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: part of complex O-linked glycosylation, which is necessary for targeting of Skp-1-protein to the nucleus
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additional information
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Substrates: substrate specificity of recombinant Gnt1 hydrid enzyme, although synthetic 13-mer and 23-mer hydroxyproline peptides are substrates, their activities are much lower even at 5000fold higher concentration, the 40-mer hydroxyproline peptide is also a poor substrate, overview
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additional information
?
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Substrates: substrate specificity of recombinant Gnt1 hydrid enzyme, although synthetic 13-mer and 23-mer hydroxyproline peptides are substrates than Skyp1A, their activities are much lower even at 5000fold higher concentration, the 40-mer hydroxyproline peptide is also a poor substrate, overview
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additional information
?
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Substrates: no activity with nonhydroxylated Skp-1-protein or -peptide
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyproline
Substrates: enzyme is involved in O-glycosylation of Skp1-protein and mucin formation
Products: -
Products: -
?
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
Products: -
Products: -
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UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
Products: -
Products: -
?
UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
Products: -
Products: -
?
UDP-N-acetylglucosamine + polypeptide-hydroxyamino acid
UDP + polypeptide-O-(alpha-N-acetyl-D-glucosaminyl)hydroxyamino acid
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Substrates: -
Products: -
Products: -
?
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
Substrates: -
Products: -
Products: -
?
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: -
Products: -
Products: -
?
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: -
Products: -
Products: -
?
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: -
Products: -
Products: -
?
UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline
UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline
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Substrates: part of complex O-linked glycosylation, which is necessary for targeting of Skp-1-protein to the nucleus
Products: -
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
additional information
additional information
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enzyme prefers low salt conditions, absolutely dependent on divalent cations
additional information
-
enzyme prefers low salt conditions, absolutely dependent on divalent cations
additional information
-
enzyme prefers low salt conditions, absolutely dependent on divalent cations
additional information
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enzyme prefers low salt conditions, absolutely dependent on divalent cations
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
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Skp-1-protein isoform containing unhydroxylated proline143 is probably inhibitory
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ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
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LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
additional information
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
metabolism
additional information
metabolism
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a hypoxia inducible factor-alpha (HIFR) type prolyl 4-hydroxylase, P4H1, and an alpha-N-acetylglucosaminyltransferase Gnt1, sequentially modify proline 143 of Skp1, a subunit of the Skp1/Cullin/F-box protein, SCF, class of E3 ubiquitin ligases
metabolism
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a hypoxia inducible factor-alpha (HIFR) type prolyl 4-hydroxylase, P4H1, and an alpha-N-acetylglucosaminyltransferase Gnt1, sequentially modify proline 143 of Skp1, a subunit of the Skp1/Cullin/F-box protein, SCF, class of E3 ubiquitin ligases
additional information
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Gnt1 from Dictyostelium discoideum contains a stretch of 80 Asn residues and other Asn-rich inserts
additional information
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Gnt1 from Dictyostelium purureum lacks a stretch of 80 Asn residues and other Asn-rich inserts
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UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
47500
x * 47500, wild-type enzyme and mutants K23R, D102A, H104D, and L276S, SDS-PAGE
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
?
x * 47500, wild-type enzyme and mutants K23R, D102A, H104D, and L276S, SDS-PAGE
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
L276S
site-directed mutagenesis, 7% remaining activity compared to the wild-type enzyme
additional information
C-terminal deletion mutants GnT51(1-282) and GnT51(1-369+) show no remaining activity
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TEMPERATURE STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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GENERAL STABILITY
ORGANISM
UNIPROT
LITERATURE
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
recombinant His-tagged hybrid Gnt1, formed of Dictyostelium discoideum Gnt1/Dictyostelium purpureum Gnt1, from Escherichia coli by nickel affinity chromatography
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recombinant wild-type enzyme and mutants from Escherichia coli as CBD-intein tagged proteins, to near homogeneity
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
cloning of a hybrid Gnt1, the coding sequence is generated from the 16 amino acid exon 1 of Dictyostelium discoideum Gnt1 and exon 2 of Dictyostelium purpureum Gnt1, and expression in Escherichia coli as His-tagged protein
gene GnT51, DNA sequence determination and analysis, functional expression of wild-type and mutants as fusion proteins with CBD-intein, in Escherichia coli strain ER2566, autocleavage of tag moiety
cloning of a hybrid Gnt1, the coding sequence is generated from the 16 amino acid exon 1 of Dictyostelium discoideum Gnt1 and exon 2 of Dictyostelium purpureum Gnt1, and expression in Escherichia coli as His-tagged protein
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cloning of a hybrid Gnt1, the coding sequence is generated from the 16 amino acid exon 1 of Dictyostelium discoideum Gnt1 and exon 2 of Dictyostelium purpureum Gnt1, and expression in Escherichia coli as His-tagged protein
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
van der Wel, H.; Morris, H.R.; Panico, M.; Paxton, T.; Dell, A.; Kaplan, L.; West, C.M.
Molecular cloning and expression of a UDP-N-acetylglucosamine (GlcNAc):hydroxyproline polypeptide GlcNAc-transferase that modifies Skp1 in the cytoplasm of Dictyostelium
J. Biol. Chem.
277
46328-46337
2002
Dictyostelium discoideum (Q8T1C6)
brenda
Teng-umnuay, P.; van der Wel, H.; West, C.M.
Identification of a UDP-GlcNAc:Skp1-hydroxyproline GlcNAc-transferase in the cytoplasm of Dictyostelium
J. Biol. Chem.
274
36392-36402
1999
Dictyostelium sp.
brenda
West, C.M.; van der Wel, H.; Gaucher, E.A.
Complex glycosylation of Skp1 in Dictyostelium: implications for the modification of other eukaryotic cytoplasmic and nuclear proteins
Glycobiology
12
17R-27R
2002
Dictyostelium discoideum (Q8T1C6), Dictyostelium sp.
brenda
West, C.M.; van der Wel, H.; Sassi, S.; Gaucher, E.A.
Cytoplasmic glycosylation of protein-hydroxyproline and its relationship to other glycosylation pathways
Biochim. Biophys. Acta
1673
29-44
2004
Chlamydomonas reinhardtii, Dictyostelium discoideum (Q8MZN0), Phytophthora sojae, Thalassiosira pseudonana, Toxoplasma gondii
brenda
van der Wel, H.; Johnson, J.M.; Xu, Y.; Karunaratne, C.V.; Wilson, K.D.; Vohra, Y.; Boons, G.J.; Taylor, C.M.; Bendiak, B.; West, C.M.
Requirements for Skp1 processing by cytosolic prolyl 4(trans)-hydroxylase and alpha-N-acetylglucosaminyltransferase enzymes involved in O2 signaling in dictyostelium
Biochemistry
50
1700-1713
2011
Dictyostelium discoideum, Dictyostelium purpureum
brenda
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