Purification and characterization of a novel thermophilic β-galactosidase from Picrophilus torridus of potential industrial application

Intracellular β-galactosidase (E.C 3.2.1.23) produced by the thermoacidophilic archeon Picrophilus torridus DSM 9790 was purified to homogeneity using a combination of DEAE Sepharose, gel filtration, hydroxyapatite and chromatofocusing chromatographies. LC–MS/MS analysis was used to confirm the identity of the purified protein. The enzyme was found to be a homotrimer, with a molecular mass of 157.0 kDa and an isoelectric point of 5.7. To our...