Expression, purification, crystallization and preliminary X-ray analysis of the κ-carrageenase from Pseudoalteromonas carrageenovora

A recombinant form of His-tagged κ-carrageenase from Pseudoalteromonas carrageenovora has been expressed, purified and crystallized. Crystals have been obtained by the vapour-diffusion method using polyethylene glycol (M_r = 4000) as a precipitant. These crystals belong to the space group P2₁2₁2₁, with unit-cell parameters a  =  58.2, b  =  62.8, c  =  77.9 Å, and diffract to 2.2 Å resolution on a rotating-anode X-ray source.