Crystallization And Preliminary X-Ray Diffraction Analysis Of Cold-Active P-Galactosidase From Arthrobacter Sp. C2-2

摘要

beta-Galactosidase from psychrotrophic bacteria strain Arthrobacter sp. C2-2 catalyzes cleavage of p-o-galactosyl moieties from beta-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 A were collected. The crystals belong to the monoclinic space group P21 with unit-cell parameters a - 140.1 A, b = 205.7 A, c = 140.5 A and (3 = 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.