ARS | Publication request: Lipoxygenase, a key enzyme in bioconversion of linoleic acid into trihydroxy-octadecenoic acid by Pseudomonas aeruginosa PR3

Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: May 21, 2008
Publication Date: May 21, 2008
Citation: Bae, J., Suh, M., Hou, C.T., Kim, H. 2008. Lipoxygenase, a key enzyme in bioconversion of linoleic acid into trihydroxy-octadecenoic acid by Pseudomonas aeruginosa PR3 [abstract]. American Oil Chemists' Society. Bio-1, #9.

Technical Abstract: Lipoxygenases catalyze the oxidation of unsaturated fatty acids with a (1Z,4Z)-pentadiene structure leading to the formation of conjugated (Z,E)-hydroperoxydienoic acids, which in turn result in production of hydroxy lipid. These enzymes are widely distributed in plants, animals, and microorganisms. Production of hydroxy fatty acids from different fatty acid substrates by microorganisms was studied. Among those microorganisms, Pseudomonas aeruginosa PR3 is well known to produce mono-, di- and trihydroxy fatty acids from their corresponding substrates. PR3 converted linoleic acid to trihydroxy fatty acid suggesting that lipoxygenase could be involved in this bioconversion. Therefore, we tried to isolate a lipoxygenase from P. aeruginosa PR3. As a result, we partially purified a lipoxygenase with 20.6-fold purification and 3.08 % recovery. The Km and Vmax values of the purified enzyme were 4.923 mM and 0.815 µmole/min/mg protein, respectively. The optimal pH and temperature for activity were pH 6.0 and 60°C, respectively. The purified enzyme was highly heat stable and showed substrate specificity only for polyunsaturated fatty acids carrying more than two double bonds.