title: Evolutionary alteration of ALOX15 specificity optimizes the biosynthesis of antiinflammatory and proresolving lipoxins.
abstract: ALOX15 (12/15-lipoxygenase) orthologs have been implicated in maturational degradation of intracellular organelles and in the biosynthesis of antiinflammatory and proresolving eicosanoids. Here we hypothesized that lower mammals (mice, rats, pigs) express 12-lipoxygenating ALOX15 orthologs. In contrast, 15-lipoxygenating isoforms are found in higher primates (orangutans, men), and these results suggest an evolution of ALOX15 specificity. To test this hypothesis we first cloned and characterized ALOX15 orthologs of selected Catarrhini representing different stages of late primate evolution and found that higher primates (men, chimpanzees) express 15-lipoxygenating orthologs. In contrast, lower primates (baboons, rhesus monkeys) express 12-lipoxygenating enzymes. Gibbons, which are flanked in evolution by rhesus monkeys (12-lipoxygenating ALOX15) and orangutans (15-lipoxygenating ALOX15), express an ALOX15 ortholog with pronounced dual specificity. To explore the driving force for this evolutionary alterations, we quantified the lipoxin synthase activity of 12-lipoxygenating (rhesus monkey, mouse, rat, pig, humIle418Ala) and 15-lipoxygenating (man, chimpanzee, orangutan, rabbit, ratLeu353Phe) ALOX15 variants and found that, when normalized to their arachidonic acid oxygenase activities, the lipoxin synthase activities of 15-lipoxygenating ALOX15 variants were more than fivefold higher (P < 0.01) [corrected]. Comparative molecular dynamics simulations and quantum mechanics/molecular mechanics calculations indicated that, for the 15-lipoxygenating rabbit ALOX15, the energy barrier for C13-hydrogen abstraction (15-lipoxygenation) was 17 kJ/mol lower than for arachidonic acid 12-lipoxygenation. In contrast, for the 12-lipoxygenating Ile418Ala mutant, the energy barrier for 15-lipoxygenation was 10 kJ/mol higher than for 12-lipoxygenation. Taken together, our data suggest an evolution of ALOX15 specificity, which is aimed at optimizing the biosynthetic capacity for antiinflammatory and proresolving lipoxins.
authors.affiliation: Institute of Biochemistry, University Medicine Berlin-Charité, D-10117 Berlin, Germany;
authors.forename: Susan
authors.initials: S
authors.lastname: Adel
authors.affiliation: Institute of Biochemistry, University Medicine Berlin-Charité, D-10117 Berlin, Germany;
authors.forename: Felix
authors.initials: F
authors.lastname: Karst
authors.affiliation: Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain;
authors.forename: Àngels
authors.initials: À
authors.lastname: González-Lafont
authors.affiliation: Institute of Biochemistry, University Medicine Berlin-Charité, D-10117 Berlin, Germany; Department of Cell and Molecular Biology of Drugs, Faculty of Pharmacy, Comenius University, 832 32 Bratislava, Slovakia.
authors.forename: Mária
authors.initials: M
authors.lastname: Pekárová
authors.affiliation: Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain;
authors.forename: Patricia
authors.initials: P
authors.lastname: Saura
authors.affiliation: Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain;
authors.forename: Laura
authors.initials: L
authors.lastname: Masgrau
authors.affiliation: Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain;
authors.forename: José M
authors.initials: JM
authors.lastname: Lluch
authors.affiliation: Institute of Biochemistry, University Medicine Berlin-Charité, D-10117 Berlin, Germany;
authors.forename: Sabine
authors.initials: S
authors.lastname: Stehling
authors.affiliation: Institute of Biochemistry, University Medicine Berlin-Charité, D-10117 Berlin, Germany;
authors.forename: Thomas
authors.initials: T
authors.lastname: Horn
authors.affiliation: Institute of Biochemistry, University Medicine Berlin-Charité, D-10117 Berlin, Germany; hartmut.kuehn@charite.de.
authors.forename: Hartmut
authors.initials: H
authors.lastname: Kuhn
authors.affiliation: Institute of Biochemistry, University Medicine Berlin-Charité, D-10117 Berlin, Germany;
authors.forename: Dagmar
authors.initials: D
authors.lastname: Heydeck
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000378:metabolism; D001093:Arachidonate 15-Lipoxygenase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D020134:Catalytic Domain; D019143:Evolution, Molecular; D006801:Humans; D044045:Lipoxins / Q000096:biosynthesis* / Q000737:chemistry; D051379:Mice; D009154:Mutation; D011323:Primates; D011817:Rabbits; D051381:Rats; D013045:Species Specificity; D013379:Substrate Specificity; D013552:Swine
chemical_list: D000893:Anti-Inflammatory Agents; D044045:Lipoxins; C515716:ALOX15 protein, human; D001093:Arachidonate 15-Lipoxygenase
keywords: eicosanoids; evolution; inflammation; lipoxygenase; protein design