galactose mutarotase

{{Short description|Protein-coding gene in the species Homo sapiens}}

{{Infobox_gene}}

Galactose mutarotase (aldose 1-epimerase) (gene name GALM) is a human enzyme that reversibly converts α-aldose to the β-anomer.{{cite journal | vauthors = Thoden JB, Timson DJ, Reece RJ, Holden HM | title = Molecular structure of human galactose mutarotase | language = English | journal = The Journal of Biological Chemistry | volume = 279 | issue = 22 | pages = 23431–23437 | date = May 2004 | pmid = 15026423 | doi = 10.1074/jbc.M402347200 | doi-access = free }} This enzyme catalyzes the first step of the Leloir pathway, which is involved in galactose metabolism.{{cite journal | vauthors = Holden HM, Rayment I, Thoden JB | title = Structure and function of enzymes of the Leloir pathway for galactose metabolism | journal = The Journal of Biological Chemistry | volume = 278 | issue = 45 | pages = 43885–43888 | date = November 2003 | pmid = 12923184 | doi = 10.1074/jbc.R300025200 | author2-link = Ivan Rayment | doi-access = free }} It belongs to family of aldose epimerases.

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.{{cite journal | vauthors = Thoden JB, Kim J, Raushel FM, Holden HM | title = The catalytic mechanism of galactose mutarotase | journal = Protein Science | volume = 12 | issue = 5 | pages = 1051–1059 | date = May 2003 | pmid = 12717027 | pmc = 2323875 | doi = 10.1110/ps.0243203 }}