Function
Mannosidase (MAN) is an enzyme which hydrolyzes mannose. There are 2 kinds of MAN. α-MAN which hydrolyzes α-mannose[1] and β-MAN which hydrolyzes β-1,4-linked manno-oligosaccharides[2]. α-MAN isozymes are classified as class I and II. Mannan endo-1,4-β-MAN hydrolyzes 1-4-β-D-mannosidic linkages in mannans, galactomannans and glucomannans. See some details in Molecular Playground/ERMan1. See also Carbohydrate Metabolism.
Disease
α-mannosidosis is manifested by accumulation of mannose-containing oligosaccharides leading to mental retardation, hearing impairment, skeletal changes and immunodeficiency[3]. β-MAN deficiency called β-mannosidosis is a disorder of oligosaccharide metabolism[4].
Structural highlights
[5]. Water molecules shown as red spheres.
3D structures of mannosidase
Mannosidase 3D structures