Corynebacterium glutamicumからのフマラーゼの精製と基質アナログ阻害

Purification of Fumarase from Corynebacterium glutamicum andInhibition by Substrate Analogs

Creators Genda Tomoko

Creators Watabe Shoji

Creators Ozaki Hachiro

Fumarase (EC 4.2.1.2) from Corynebacterium glutamicum (Breuibacterium flavum) ATCC 14067 was purified to homogeneity. Its amino-terminal sequence (residues 1 to 30) corresponded to the sequence (residues 6 to 35) of the deduced product of the fumarase gene of C. glutamicum (GeneBank accession no. BAB98403) . The molecular mass of the native enzyme was 200 kDa. The protein was a homotetramer, with a 50-kDa subunit molecular mass. The homotetrameric and stable properties indicated that the enzyme belongs to a family of Class II fumarase. Equilibrium constants (Keq) for the enzyme reaction were determined at pH 6.0, 7.0, and 8.0, resulting in Keq = 6.4, 6.1, and 4.6 in phosphate buffer, while 16, 19, and 17 in the non-phosphate buffers, respectively. Among amino acids and nucleotides tested ATP inhibited the enzyme. Substrate analogs, meso-tartrate, D-tartrate, and pyromellitate, inhibited the enzyme competitively, and D-malate in mixed-type.

[ISSN]1349-810X

[NCID]AN00243950