Feruloyl esterase (FAE; EC 3.1.1.73) catalyzes the cleavage of the ester bond between ferulic acid and polysaccharides in plant cell walls, and thus holds significant potential for the industrial utilization of biomass saccharification. A feruloyl esterase was identified from the genome database of Talaromyces cellulolyticus (formerly known as Acremonium cellulolyticus). The gene consists of the catalytic domain and a carbohydrate-binding module connected through a serine/threonine-rich linker region. The recombinant enzyme was prepared, purified and crystallized at 293 K using 0.1 M imidazole pH 8.0, 0.2 M calcium acetate, 14% PEG 8000 as the precipitant. The crystal diffracted to 2.6 Å resolution and the crystal system is primitive orthorhombic, with unit-cell parameters a = 90.9, b = 123.4, c = 135.4 Å. Four molecules are assumed to be present per asymmetric unit, corresponding to a Matthews coefficient of 2.50 Å(3) Da(-1) and a solvent content of 50.88%(v/v).
Keywords: biomass; carbohydrate-binding module; cellulase; fungus.