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Related Experiment Video

Updated: Jul 7, 2026

Measuring Lactase Enzymatic Activity in the Teaching Lab

Measuring Lactase Enzymatic Activity in the Teaching Lab

Published on: August 6, 2018

Galactokinase: structure, function and role in type II galactosemia.

H M Holden¹, J B Thoden, D J Timson

¹Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706, USA. hazel_holden@biochem.wisc.edu.

Cellular and Molecular Life Sciences : CMLS

|November 5, 2004

Summary

Galactokinase is a key enzyme in galactose metabolism, crucial for preventing galactosemia. Recent X-ray crystallography reveals its structure, aiding in understanding its function and potential therapeutic applications.

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Area of Science:

Biochemistry
Molecular Biology
Enzymology

Background:

The Leloir pathway converts beta-D-galactose to glucose 1-phosphate via four enzymes.
Galactokinase (GALK) catalyzes the conversion of alpha-D-galactose to galactose 1-phosphate, a critical step.
Defects in human GALK cause galactosemia, a serious metabolic disorder.

Purpose of the Study:

To review recent X-ray crystallographic analyses of galactokinase.
To contextualize the enzyme's molecular architecture with existing biochemical data.
To highlight GALK's metabolic significance, disease association, and biotechnological applications.

Main Methods:

X-ray crystallography
Biochemical assays
Literature review of accumulated data over 40 years.

Main Results:

Recent crystallographic studies provide detailed insights into galactokinase's molecular structure.
The structural data complements extensive biochemical information on the enzyme's function.
Galactokinase's role extends beyond metabolism to sensing and transcriptional regulation.

Conclusions:

Understanding galactokinase's structure-function relationship is vital for metabolic research and galactosemia treatment.
Directed evolution of galactokinase offers potential for novel sugar phosphate synthesis.
Galactokinase's multifaceted roles underscore its importance in cellular processes.