Expression, purification and preliminary X‐ray analysis of the Neisseria meningitidis outer membrane protein PorB

The Neisseria meningitidis outer membrane protein PorB was expressed in Escherichia coli and purified from inclusion bodies by denaturation in urea followed by refolding in buffered LDAO on a size‐exclusion column. PorB has been crystallized in three different crystal forms: C 222, R 32 and P 6 3 . The C 222 crystal form may contain either one or two PorB monomers in the asymmetric unit, while both the R 32 and P 6 3 crystal forms contained one PorB monomer in the asymmetric unit. Of the three, the P 6 3 crystal form had the best diffraction quality, yielding data extending to 2.3 Å resolution.