Crystallization and preliminary X-ray analysis of a cold-active β-galactosidase from the psychrotrophic and halotolerant Planococcus sp. L4.

β-Galactosidases catalyze the hydrolysis of a galactosyl moiety from the nonreducing termini of oligosaccharides or from glycosides. A novel GH family 42 cold-active β-galactosidase identified from the psychrotrophic and halotolerant Planococcus sp. L4 (BgaP) was crystallized and a complete data set was collected from a single frozen crystal on an in-house X-ray source. The crystal diffracted to 2.8 Å resolution and belonged to space group P1, with unit-cell parameters a = 104.29, b = 118.12, c = 121.12 Å, α = 62.66, β = 69.48, γ = 70.74°. A likely Matthews coefficient of 2.58 Å(3) Da(-1) and solvent content of 52.32% suggested the presence of six protein subunits in the asymmetric unit.