|Bae, Ja-Han - KYUNGPOOK NATL UNIV KOREA|
|Suh, Min-Jung - KYUNGPOOK NATL UNIV KOREA|
|Kim, Hak-Ryul - KYUNGPOOK NATL UNIV KOREA|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 21, 2008
Publication Date: November 21, 2008
Citation: Bae, J., Suh, M., Hou, C.T., Kim, H. 2008. Thermostable lipoxygenase, a key enzyme in bioconversion of linoleic acid to trihycroxy-octadecenoic acid by Pseudomonas aeruginosa PR3 [abstract]. International Society of Biocatalysis and Biotechnology. L-3. p. 77. Technical Abstract: Lipoxygenases, enzymes that contain non-heme iron, catalyze the oxidation of unsaturated fatty acids with a (1Z,4Z)-pentadiene moiety leading to conjugated (Z,E)-hydroperoxydienoic acids. These enzymes are widely distributed in plants and animals, and a few microorganisms are reported as well. It was reported that conversion of linoleic hydroperoxide by soybean lipoxygenase generated trihydroxy-, hydroperoxy dihydroxy-, hydroxyepoxy-octadecenoate, and lipid hydroperoxide. These reaction products are also known in many other higher plants. Previously, we reported that Pseudomonas aeruginosa PR3 converted linoleic acid to equimolar mixture of 9,10,13-trihydroxy-11(E)-octadecenoic acid and 9,12,13-trihydroxy-10(E)-octadecenoic acid. These results allowed us to address identification of new lipoxygenase in P. aeruginosa PR3. As a result, we isolated a protein carrying lipoxygenase activity from P. aeruginosa PR3 with 20.6-fold purification and 3.1% of recovery. The Km and Vmax value of the purified enzyme was 4.923 mM and 0.815 µM•min-1•mg-1, respectively. The optimal pH and temperature was 6.0 and and 60 degrees Celsius, respectively. Moreover, this enzyme is highly thermostable representing 60% of the initial activity after incubation at 80 degrees Celsius for 2 hours.