Collect. Czech. Chem. Commun. 2005, 70, 124-132

Crystallization and Preliminary X-ray Diffraction Analysis of Cold-Active β-Galactosidase from Arthrobacter sp. C2-2

Hana Petrokováa, Eva Vondráčkováa, Tereza Skálováa, Jan Dohnáleka, Petra Lipovováb, Vojtěch Spiwokb, Hynek Strnadb, Blanka Králováb and Jindřich Hašeka,*

a Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic
b Department of Biochemistry, Institute of Chemical Technology, Prague, Technická 5,  166 28 Prague 6, Czech Republic


β-Galactosidase from psychrotrophic bacteria strain Arthrobacter sp. C2-2 catalyzes cleavage of β-D-galactosyl moieties from β-D-galactosides and is interesting for its activity at low temperatures. Various types of crystals with dimensions of up to 0.8 mm were obtained and X-ray diffraction data up to 1.9 Å were collected. The crystals belong to the monoclinic space group P21 with unit-cell parameters a = 140.1 Å, b = 205.7 Å, c = 140.5 Å and β = 102.3°. The enzyme (molecular weight of a monomer is 111 kDa) forms hexamers in the crystal structure (one hexamer per asymmetric unit). The phase problem was solved by molecular replacement. Structure refinement is in progress.

Keywords: Galactosidases; Glycosidases; Psychrotrophic; X-Ray diffraction; Crystallization; Crystal growth; Crystal structure determination; Enzymes.

References: 20 live references.