Galactosylceramidase (or galactocerebrosidase), , is an
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 removes
galactose
Galactose (, ''wikt:galacto-, galacto-'' + ''wikt:-ose#Suffix 2, -ose'', ), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweetness, sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epime ...
from
ceramide
Ceramides are a family of waxy lipid molecules. A ceramide is composed of sphingosine and a fatty acid joined by an amide bond. Ceramides are found in high concentrations within the cell membrane of Eukaryote, eukaryotic cells, since they are co ...
derivatives (
galactosylceramide
A galactosylceramide, or galactocerebroside is a type of cerebroside consisting of a ceramide with a galactose residue at the 1-hydroxyl moiety.
The galactose is cleaved by galactosylceramidase.
Galactosylceramide is a marker for oligodendrocyt ...
s) by catalysing the hydrolysis of
galactose
Galactose (, ''wikt:galacto-, galacto-'' + ''wikt:-ose#Suffix 2, -ose'', ), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweetness, sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epime ...
ester bonds of
galactosylceramide
A galactosylceramide, or galactocerebroside is a type of cerebroside consisting of a ceramide with a galactose residue at the 1-hydroxyl moiety.
The galactose is cleaved by galactosylceramidase.
Galactosylceramide is a marker for oligodendrocyt ...
, galactosylsphingosine,
lactosylceramide
The Lactosylceramides, also known as LacCer, are a class of glycosphingolipids composed of a variable hydrophobic ceramide lipid and a hydrophilic sugar moiety. Lactosylceramides are found in microdomains on the plasma layers of numerous cells ...
, and monogalactosyldiglyceride.
It is a
lysosomal
A lysosome () is a membrane-bound organelle that is found in all mammalian cells, with the exception of red blood cells (erythrocytes). There are normally hundreds of lysosomes in the cytosol, where they function as the cell’s degradation cent ...
protein, encoded in humans by the ''GALC''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
Mutations in this gene have been associated with
Krabbe disease
Krabbe disease (KD) (also known as globoid cell leukodystrophy or galactosylceramide lipidosis) is a rare and often fatal lysosomal storage disease that results in progressive damage to the nervous system. KD involves dysfunctional metabolism o ...
, also known as galactosylceramide lipidosis.
References
Further reading
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
External links
GeneReviews/NCBI/NIH/UW entry on Krabbe disease OMIM entries on Krabbe disease*
PDBe-KBprovides an overview of all the structure information available in the PDB for Mlouse Galactocerebrosidase
EC 3.2.1
{{3.2-enzyme-stub