Structure of PDB 1ek5 Chain A

Receptor sequence

>1ek5A (length=346) Species: 9606 (Homo sapiens)

MAEKVLVTGGAGYIGSHTVLELLEAGYLPVVIDNFHNAFRGGGSLPESLR
RVQELTGRSVEFEEMDILDQGALQRLFKKYSFMAVIHFAGLKAVGESVQK
PLDYYRVNLTGTIQLLEIMKAHGVKNLVFSSSATVYGNPQYLPLDEAHPT
GGCTNPYGKSKFFIEEMIRDLCQADKTWNAVLLRYFNPTGAHASGCIGED
PQGIPNNLMPYVSQVAIGRREALNVFGNDYDTEDGTGVRDYIHVVDLAKG
HIAALRKLKEQCGCRIYNLGTGTGYSVLQMVQAMEKASGKKIPYKVVARR
EGDVAACYANPSLAQEELGWTAALGLDRMCEDLWRWQKQNPSGFGT

3D structure

• PDB: 1ek5 Crystallographic evidence for Tyr 157 functioning as the active site base in human UDP-galactose 4-epimerase.
• Chain: A
• Resolution: 1.8 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): S132 A133 T134 Y157 K161
• Catalytic site (residue number reindexed from 1): S132 A133 T134 Y157 K161
• Enzyme Commision number: 5.1.3.2: UDP-glucose 4-epimerase.
  5.1.3.7: UDP-N-acetylglucosamine 4-epimerase.

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	NAD	A	G9 G12 Y13 I14 D33 N34 H36 N37 D66 F88 G90 K92 S131 Y157 K161 Y185 P188	G9 G12 Y13 I14 D33 N34 H36 N37 D66 F88 G90 K92 S131 Y157 K161 Y185 P188

Gene Ontology

Molecular Function

• GO:0003974 UDP-N-acetylglucosamine 4-epimerase activity
• GO:0003978 UDP-glucose 4-epimerase activity
• GO:0016853 isomerase activity
• GO:0042802 identical protein binding
• GO:0042803 protein homodimerization activity

Biological Process

• GO:0006012 galactose metabolic process
• GO:0019388 galactose catabolic process
• GO:0033499 galactose catabolic process via UDP-galactose

Cellular Component

• GO:0005829 cytosol

External links

• PDB: RCSB:1ek5, PDBe:1ek5, PDBj:1ek5
• PDBsum: 1ek5
• PubMed: 10801319
• UniProt: Q14376|GALE_HUMAN UDP-glucose 4-epimerase (Gene Name=GALE)