β-Mannosidase (EC 3.2.1.25) is an exoglycosidase specific for the hydrolysis of terminal β-linked mannoside in various sugar chains. cDNA corresponding to the β-mannosidase gene was cloned from Aspergillus niger, sequenced, and expressed in the yeast Pichia pastoris. The β-mannosidase gene contains an open reading frame which encodes the protein with 933 amino acid residues. The wild type and recombinant proteins were purified to apparent homogeneity and biochemically characterized (K(M) 0.28 and 0.44 mmol/l for p-nitrophenyl β-d-mannopyranoside, pI 4.2 and 4.0, and their pH optima were at pH 4.5 and 5.5 and 65°C, respectively).

Laboratory of Biotransformation Institute of Microbiology Academy of Sciences of the Czech Republic Vídeňská 1083 Prague Czech Republic

Citace poskytuje Crossref.org

Crystallization and preliminary X-ray crystallographic analysis of recombinant β-mannosidase from Aspergillus niger