Galactose mutarotase

Galactose mutarotase (aldose 1-epimerase) (gene name GALM) is a human enzyme that reversibly converts α-aldose to the β-anomer.^[5] This enzyme catalyzes the first step of the Leloir pathway, which is involved in galactose metabolism.^[6] It belongs to family of aldose epimerases.

GALM
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1SNZ, 1SO0
Identifiers
Aliases	GALM, BLOCK25, GLAT, HEL-S-63p, IBD1, galactose mutarotase (aldose 1-epimerase), galactose mutarotase, GALAC4
External IDs	OMIM: 137030; MGI: 2442420; HomoloGene: 71795; GeneCards: GALM; OMA:GALM - orthologs
Gene location (Human) Chr. Chromosome 2 (human)[1] Band 2p22.1 Start 38,666,081 bp[1] End 38,741,237 bp[1]
Gene location (Mouse) Chr. Chromosome 17 (mouse)[2] Band 17|17 E3 Start 80,434,900 bp[2] End 80,492,530 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in right adrenal gland right adrenal cortex pancreatic ductal cell left adrenal gland left adrenal cortex duodenum right uterine tube renal medulla jejunal mucosa human kidney Top expressed in olfactory epithelium lacrimal gland vestibular membrane of cochlear duct left lobe of liver epithelium of stomach jejunum gallbladder right kidney primary oocyte superior surface of tongue More reference expression data BioGPS n/a
Gene ontology Molecular function isomerase activity aldose 1-epimerase activity carbohydrate binding catalytic activity Cellular component extracellular exosome cytoplasm Biological process hexose metabolic process glucose metabolic process galactose metabolic process galactose catabolic process via UDP-galactose carbohydrate metabolic process Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 130589 319625 Ensembl ENSG00000143891 ENSMUSG00000035473 UniProt Q96C23 Q8K157 RefSeq (mRNA) NM_138801 NM_176963 RefSeq (protein) NP_620156 NP_795937 Location (UCSC) Chr 2: 38.67 – 38.74 Mb Chr 17: 80.43 – 80.49 Mb PubMed search [3] [4]
Wikidata
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The two main amino acids in the enzyme active site are Glu 304, which acts as a Bronsted-Lowry base and abstracts a proton, and His 170, which acts as Bronsted-Lowry Acid to donate a proton to the galactose.^[7]