The gene encoding D-tagatose 3-epimerase (D-TE) from Pseudomonas cichorii ST-24 was cloned and sequenced. It was found to consist of 873 bp encoding 290 amino acid residues. The molecular weight of the deduced amino acid sequence of D-TE was determined to be 32.5 kDa. The deduced amino acid sequence showed no extensive homology with sequences of other sugar-related epimerases, but homology was observed with several hypothetical proteins of procaryotes, i.e. Synechocystis sp., Bacillus subtilis, Haemophilus influenzae, and Escherichia coli. The D-TE gene was expressed in E. coil.