Glucosidases

Not to be confused with Glycosidase.

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Beta-amylase, a type of glucosidase

Glucosidases are the glycoside hydrolase enzymes categorized under the EC number 3.2.1.

Function

Alpha-glucosidases are enzymes involved in breaking down complex carbohydrates such as starch and glycogen into their monomers.

They catalyze the cleavage of individual glucosyl residues from various glycoconjugates including alpha- or beta-linked polymers of glucose. This enzyme converts complex sugars into simpler ones.

Members

Different sources include different members in this class. Members marked with a "#" are considered by MeSH to be glucosidases.

Name	EC	Description
α-Amylase	EC 3.2.1.1	is a digestive enzyme in mammals
β-Amylase	EC 3.2.1.2	is a plant enzyme to break down starch
γ-Amylase	EC 3.2.1.3	is a digestive enzyme
Cellulase #	EC 3.2.1.4	breaks down cellulose from plant material
Sucrase-isomaltase	EC 3.2.1.10	-
Mannosyl-oligosaccharide glucosidase #	EC 3.2.1.106	catalyzes the first trimming step of the N-glycosylation pathway; is associated with Congenital Disorder of Glycosylation type IIb
Acid α-glucosidase #	EC 3.2.1.20	is associated with Glycogen storage disease type II
Beta-glucosidase #	EC 3.2.1.21	is associated with Gaucher's disease
Lactase	EC 3.2.1.23	one member of the β-galactosidase family, breaks down milk sugars, and its absence in adulthood causes lactose intolerance
Debranching enzyme #	EC 3.2.1.33	in mammals, yeast and some bacteria, combines transferase and glucosidase activity in glycogen breakdown
Pullulanase	EC 3.2.1.41	has been used as a detergent

Clinical significance

Alpha-glucosidases are targeted by alpha-glucosidase inhibitors such as acarbose and miglitol to control diabetes mellitus type 2.

See also

• DNA glycosylases
• Mucopolysaccharidoses

External links

• Glucosidases at the U.S. National Library of Medicine Medical Subject Headings (MeSH)