Publications

• Biogenic synthesis, purification, and chemical characterization of anti-inflammatory resolvins derived from docosapentaenoic acid (DPAn-6).

  Dangi B., Obeng M., Nauroth J.M., Teymourlouei M., Needham M., Raman K., Arterburn L.M.

  Enzymatically oxygenated derivatives of the omega-3 fatty acids cis-4,7,10,13,16,19-docosahexaenoic acid (DHA) and cis-5,8,11,14,17-eicosapentaenoic acid, known as resolvins, have potent inflammation resolution activity (Serhan, C. N., Clish, C. B., Brannon, J., Colgan, S. P., Chiang, N., and Gron ... >> More

  Enzymatically oxygenated derivatives of the omega-3 fatty acids cis-4,7,10,13,16,19-docosahexaenoic acid (DHA) and cis-5,8,11,14,17-eicosapentaenoic acid, known as resolvins, have potent inflammation resolution activity (Serhan, C. N., Clish, C. B., Brannon, J., Colgan, S. P., Chiang, N., and Gronert, K. (2000) J. Exp. Med. 192, 1197-1204; Hong, S., Gronert, K., Devchand, P. R., Moussignac, R., and Serhan, C. N. (2003) J. Biol. Chem. 278, 14677-14687). Our objective was to determine whether similar derivatives are enzymatically synthesized from other C-22 fatty acids and whether these molecules possess inflammation resolution properties. The reaction of DHA, DPAn-3, and DPAn-6 with 5-, 12-, and 15-lipoxygenases produced oxylipins, which were identified and characterized by liquid chromatography coupled with tandem mass-spectrometry. DPAn-6 and DPAn-3 proved to be good substrates for 15-lipoxygenase. 15-Lipoxygenase proved to be the most efficient enzyme of the three tested for conversion of long chain polyunsaturated fatty acids to corresponding oxylipins. Since DPAn-6 is a major component of Martek DHA-S oil, we focused our attention on reaction products obtained from the DPAn-6 and 15-lipoxygenase reaction. (17S)-hydroxy-DPAn-6 and (10,17S)-dihydroxy-DPAn-6 were the main products of this reaction. These compounds were purified by preparatory high performance liquid chromatography techniques and further characterized by NMR, UV spectrophotometry, and tandem mass spectrometry. We tested both compounds in two animal models of acute inflammation and demonstrated that both compounds are potent anti-inflammatory agents that are active on local intravenous as well as oral administration. These oxygenated DPAn-6 compounds can thus be categorized as a new class of DPAn-6-derived resolvins. << Less

  J. Biol. Chem. 284:14744-14759(2009) [PubMed] [EuropePMC]

  This publication is cited by 8 other entries.

• Structural and functional basis of phospholipid oxygenase activity of bacterial lipoxygenase from Pseudomonas aeruginosa.

  Banthiya S., Kalms J., Galemou Yoga E., Ivanov I., Carpena X., Hamberg M., Kuhn H., Scheerer P.

  Pseudomonas aeruginosa expresses a secreted LOX-isoform (PA-LOX, LoxA) capable of oxidizing polyenoic fatty acids to hydroperoxy derivatives. Here we report high-level expression of this enzyme in E. coli and its structural and functional characterization. Recombinant PA-LOX oxygenates polyenoic f ... >> More

  Pseudomonas aeruginosa expresses a secreted LOX-isoform (PA-LOX, LoxA) capable of oxidizing polyenoic fatty acids to hydroperoxy derivatives. Here we report high-level expression of this enzyme in E. coli and its structural and functional characterization. Recombinant PA-LOX oxygenates polyenoic fatty acids including eicosapentaenoic acid and docosahexaenoic acid to the corresponding (n-6)S-hydroperoxy derivatives. This reaction involves abstraction of the proS-hydrogen from the n-8 bisallylic methylene. PA-LOX lacks major leukotriene synthase activity but converts 5S-HETE and 5S,6R/S-DiHETE to anti-inflammatory and pro-resolving lipoxins. It also exhibits phospholipid oxygenase activity as indicated by the formation of a specific pattern of oxygenation products from different phospholipid subspecies. Multiple mutagenesis studies revealed that PA-LOX does not follow classical concepts explaining the reaction specificity of mammalian LOXs. The crystal structure of PA-LOX was solved with resolutions of up to 1.48Å and its polypeptide chain is folded as single domain. The substrate-binding pocket consists of two fatty acid binding subcavities and lobby. Subcavity-1 contains the catalytic non-heme iron. A phosphatidylethanolamine molecule occupies the substrate-binding pocket and its sn1 fatty acid is located close to the catalytic non-heme iron. His377, His382, His555, Asn559 and the C-terminal Ile685 function as direct iron ligands and a water molecule (hydroxyl) completes the octahedral ligand sphere. Although the biological relevance of PA-LOX is still unknown its functional characteristics (lipoxin synthase activity) implicate this enzyme in a bacterial evasion strategy aimed at downregulating the hosts' immune system. << Less

  Biochim. Biophys. Acta 1861:1681-1692(2016) [PubMed] [EuropePMC]

  This publication is cited by 4 other entries.

• 15-Lipoxygenase-1 biosynthesis of 7S,14S-diHDHA implicates 15-lipoxygenase-2 in biosynthesis of resolvin D5.

  Perry S.C., Kalyanaraman C., Tourdot B.E., Conrad W.S., Akinkugbe O., Freedman J.C., Holinstat M., Jacobson M.P., Holman T.R.

  The two oxylipins 7S,14S-dihydroxydocosahexaenoic acid (diHDHA) and 7S,17S-diHDHA [resolvin D5 (RvD5)] have been found in macrophages and infectious inflammatory exudates and are believed to function as specialized pro-resolving mediators (SPMs). Their biosynthesis is thought to proceed through se ... >> More

  The two oxylipins 7S,14S-dihydroxydocosahexaenoic acid (diHDHA) and 7S,17S-diHDHA [resolvin D5 (RvD5)] have been found in macrophages and infectious inflammatory exudates and are believed to function as specialized pro-resolving mediators (SPMs). Their biosynthesis is thought to proceed through sequential oxidations of DHA by lipoxygenase (LOX) enzymes, specifically, by human 5-LOX (h5-LOX) first to 7(S)-hydroxy-4Z,8E,10Z,13Z,16Z,19Z-DHA (7S-HDHA), followed by human platelet 12-LOX (h12-LOX) to form 7(S),14(S)-dihydroxy-4Z,8E,10Z,12E,16Z,19Z-DHA (7S,14S-diHDHA) or human reticulocyte 15-LOX-1 (h15-LOX-1) to form RvD5. In this work, we determined that oxidation of 7(S)-hydroperoxy-4Z,8E,10Z,13Z,16Z,19Z-DHA to 7S,14S-diHDHA is performed with similar kinetics by either h12-LOX or h15-LOX-1. The oxidation at C14 of DHA by h12-LOX was expected, but the noncanonical reaction of h15-LOX-1 to make over 80% 7S,14S-diHDHA was larger than expected. Results of computer modeling suggested that the alcohol on C7 of 7S-HDHA hydrogen bonds with the backbone carbonyl of Ile399, forcing the hydrogen abstraction from C12 to oxygenate on C14 but not C17. This result raised questions regarding the synthesis of RvD5. Strikingly, we found that h15-LOX-2 oxygenates 7S-HDHA almost exclusively at C17, forming RvD5 with faster kinetics than does h15-LOX-1. The presence of h15-LOX-2 in neutrophils and macrophages suggests that it may have a greater role in biosynthesizing SPMs than previously thought. We also determined that the reactions of h5-LOX with 14(S)-hydroperoxy-4Z,7Z,10Z,12E,16Z,19Z-DHA and 17(S)-hydroperoxy-4Z,7Z,10Z,13Z,15E,19Z-DHA are kinetically slow compared with DHA, suggesting that these reactions may be minor biosynthetic routes in vivo. Additionally, we show that 7S,14S-diHDHA and RvD5 have anti-aggregation properties with platelets at low micromolar potencies, which could directly regulate clot resolution. << Less

  J. Lipid Res. 61:1087-1103(2020) [PubMed] [EuropePMC]

  This publication is cited by 5 other entries.