FEATURES

FAMILY

DESCRIPTION

Also known as AXE2_GEOSE, axe2. Acetylxylan esterase involved in the degradation of xylan, a major structural heterogeneous polysaccharide found in plant biomass representing the second most abundant polysaccharide in the biosphere, after cellulose. Cleaves acetyl side groups from the xylose backbone units of the hemicellulolytic polymer xylan and xylo-oligosaccharides. Hydrolyzes about 20%-30% of the available acetyl groups on fully acetylated birch wood xylan. Completely deacetylates xylobiose peracetate (fully acetylated), and is active on both the alpha- and beta-forms of the sugar. Also hydrolyzes fully acetylated methyl-beta-D-xylopyranoside and methyl-beta-D-glucopyranoside, and the synthetic substrates 2-naphthyl acetate, 4-nitrophenyl acetate, 4-methylumbelliferyl acetate, and phenyl acetate. Homooctamer, presenting a unique donut-shaped quaternary structure built of two staggered tetrameric rings. The eight active sites are organized in four closely situated pairs, which face the relatively wide internal cavity.

EXTERNAL LINKS

axe2

Acetylxylan esterase

axe2

Molecular Synopsis