Author
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Hou, Ching |
Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/6/2005 Publication Date: 11/15/2005 Citation: Hou, C.T. 2005. Monooxygenase system of Bacillus megaterium ALA2: Studies on palmitic acid oxidation products. Journal of the American Oil Chemists' Society. 82(11):839-843. Interpretive Summary: Previously, we discovered a new microbial strain ALA2 that produced seven new polyhydroxy unsaturated fatty acids from linoleic acid. Hydroxy fatty acids are useful as starting materials for the synthesis of specialty chemicals, special military nylon, plastisizers, and coatings materials. Polyhydroxy unsaturated fatty acids are also valuable precursors for prostaglandin and other hormones synthesis, can act as fungicides in agricultural application, are precursors of flavor ingredients, and are chiral synthons of possible drug discovery interest. Application of these new products either for bioactive agents or raw material for synthesis of specialty chemicals will benefit U.S. farmers. We have been trying to improve the products yield through manipulation of metabolic pathway enzymes. Recently, we reclassified strain ALA2 as Bacillus megaterium. Now we proved that strain ALA2 enzymes also converts palmitic acid to hydroxyl fatty acids products similar to those well studied self-sufficient cytochrome P450 monooxygenase system in Bacillus strains. These findings facilitate studies on strain ALA2 oxygenase system. Technical Abstract: We identified many novel oxygenated fatty acids produced from linoleic acid by strain ALA2: 12,13,17-trihydroxy-9(Z)-octadecenoic acid (12,13,17-THOA); 12,13,16-trihydroxy-9(z)-octadecenoic acid (12,13,16-THOA); 12-hydroxy-13,16-epoxy-9(Z)-octadecenoic acid; and 12,17;13,17-diepoxy-16-hydroxy-9(Z)-octadecenoic acid. 12,13,17-THOA, the main product, inhibits the growth of some plant pathogenic fungi. Recently, we reclassified strain ALA2 as Bacillus megaterium and opened a possible link with the well-studied catalytically self-sufficient P450 monooxygenase of Bacillus megaterium ATCC 14581 (NRRL B-3712) and Bacillus subtilis strain 168 (NRRL B-4219). Now we found that strain ALA2 also oxidizes palmitic acid into three oxygenated products: 13-, 14-, and 15-hydroxy palmitic acids. This indicated that strain ALA2 also possesses a monooxygenase system similar to the above mentioned well known strains. These data facilitate our studies on strain ALA2 oxygenase system. |