Primary Information
BoMiProt ID	Bomi2266
Protein Name	Galactokinase
Organism	Bos taurus
Uniprot ID	A6H768
Milk Fraction	Exosome
Ref Sequence ID	NP_001092851.1
Aminoacid Length	392
Molecular Weight	42227
FASTA Sequence	Download
Gene Name	GALK1
Gene ID	530855
Protein Existence Status	Reviewed: Experimental evidence at transcript level
Secondary Information
Protein Function	Galactokinase catalyses the first committed step of the Leloir pathway, i.e. the ATP-dependent phosphorylation of α-D-galactose at C1-OH.
Biochemical Properties	The bacterial enzyme is monomeric and consists of 399 amino acid residues. Its amino acid sequence is 34% identical and 47% similar to that of human galactokinase.The molecule is elongated with overall dimensions of ~70 Å X 54 Å X 57 Å and folds into two regions referred to as the N- and C-terminal domains. These domains are formed between Thr 9 to Gly 190 and Glu 191 to Gly 390, respectively. The last amino acid residues at the C-terminus curl back onto the N-terminal domain.
PTMs	Phosphorylation at Serine
Site(s) of PTM(s) N-glycosylation, O-glycosylation, Phosphorylation
Predicted Disorder Regions	NA
DisProt Annotation
TM Helix Prediction	No TM helices
Additional Comments	The phenotype of GALK1 deficiency may include neonatal elevation of transaminases, bleeding diathesis, and encephalopathy in addition to cataract.
Bibliography	1.McAuley M, Kristiansson H, Huang M, Pey AL, Timson DJ. Galactokinase promiscuity: a question of flexibility? Biochem Soc Trans. 2016 Feb;44(1):116-22. doi: 10.1042/BST20150188. PMID: 26862196. 2.Rubio-Gozalbo ME, Derks B, Das AM, Meyer U, Möslinger D, Couce ML, Empain A, Ficicioglu C, Juliá Palacios N, De Los Santos De Pelegrin MM, Rivera IA, Scholl-Bürgi S, Bosch AM, Cassiman D, Demirbas D, Gautschi M, Knerr I, Labrune P, Skouma A, Verloo P, Wortmann SB, Treacy EP, Timson DJ, Berry GT. Galactokinase deficiency: lessons from the GalNet registry. Genet Med. 2021 Jan;23(1):202-210. doi: 10.1038/s41436-020-00942-9. Epub 2020 Aug 18. PMID: 32807972; PMCID: PMC7790741. 3.Holden HM, Thoden JB, Timson DJ, Reece RJ. Galactokinase: structure, function and role in type II galactosemia. Cell Mol Life Sci. 2004 Oct;61(19-20):2471-84. doi: 10.1007/s00018-004-4160-6. PMID: 15526155.