Expression, purification, crystallization and preliminary characterization of an HHED aldolase homologue from Escherichia coli K12

An ORF from the E. coli K12 genome with 56% sequence identity to 2,4-dihydroxy-hept-2-ene-1,7-dioic acid (HHED) aldolase has been cloned, expressed and purified. Crystals obtained from the purified recombinant enzyme, belonging to space group C222₁, diffracted to a resolution of 1.78 Å.