The structural and molecular biology of type IV galactosemia

Copyright © 2020 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved..

Type IV galactosemia is a recently discovered inherited metabolic disease. It is caused by mutations in the GALM gene which result in reduced activity of the enzyme galactose mutarotase. This enzyme catalyses the interconversion of the α- and β-anomers of d-galactose and some other monosaccharides. Human galactose mutarotase is monomeric and its structure is largely composed of β-sheets. The catalytic mechanism requires a histidine residue acting as an acid, and a glutamate acting as a base. Together, these residues open the pyranose ring of d-galactose enabling free rotation of the bond between the first two carbon atoms in the monosaccharide. This can cause reversal of the configuration of the hydroxyl group attached to carbon 1. Type IV galactosemia manifests with similar symptoms to type II galactosemia (galactokinase deficiency), i.e. early onset cataracts. However, as a recently discovered disease, the longer-term consequences are unknown. The physiological role, if any, of galactose mutarotase's reactions with other monosaccharides are not yet known. The possible associations with other proteins also require further investigation.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:183

Enthalten in:

Biochimie - 183(2021) vom: 01. Apr., Seite 13-17

Sprache:

Englisch

Beteiligte Personen:

Banford, Samantha [VerfasserIn]
Timson, David J [VerfasserIn]

Links:

Volltext

Themen:

Aldose 1-epimerase
Anomers
Carbohydrate Epimerases
EC 5.1.3.-
EC 5.1.3.3
GALM
Galactose
Galactose metabolism
Galactose mutarotase
Inherited metabolic disease
Journal Article
Review
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Anmerkungen:

Date Completed 09.06.2021

Date Revised 09.06.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.biochi.2020.11.001

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM31748740X