Purification and Crystallization of Fumarase C from Escherichia coli

Fumarase C purified from Escherichia coli has been crystallized in the presence of polyethylene glycol in both a citrate buffer at pH 5·3 and a 3-(4-morpholino)-propanesulfonic acid buffer at pH 7·5 yielding two crystal forms. An orthorhombic C222 1 form was obtained in citrate at pH 5·3 and an orthorhombic I222 form was obtained in 3-(4-morpholino)-propanesulfonic acid (pH 7·5). Complete native data sets have been collected on both crystal forms: the C222 1 form is complete to 2·10 Å and the I222 form is complete to 2·20 Å.