Galactose mutarotase (aldose 1-epimerase) (gene name GALM) is a human
enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...
that reversibly converts α-
aldose
An aldose is a monosaccharide (a simple sugar) with a carbon backbone chain with a carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl groups connected to all the other carbon atoms. Aldoses can be distinguished from ket ...
to the β-
anomer
In carbohydrate chemistry, a pair of anomers () is a pair of near-identical stereoisomers or diastereomers that differ at only the anomeric carbon, the carbon atom that bears the aldehyde or ketone functional group in the sugar's open-chain for ...
. This enzyme catalyzes the first step of the
Leloir pathway, which is involved in galactose metabolism. It belongs to family of
aldose
An aldose is a monosaccharide (a simple sugar) with a carbon backbone chain with a carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl groups connected to all the other carbon atoms. Aldoses can be distinguished from ket ...
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.
References
External links
PDBe-KBprovides an overview of all the structure information available in the PDB for Human Aldose 1-epimerase (Galactose mutarotase)
{{gene-2-stub