Correction BIOCHEMISTRY Correction for “Evolutionary alteration of ALOX15 specificity optimizes the biosynthesis of antiinflammatory and proresolving lipoxins,” by Susan Adel, Felix Karst, Àngels González-Lafont, Mária Pekárová, Patricia Saura, Laura Masgrau, José M. Lluch, Sabine Stehling, Thomas Horn, Hartmut Kuhn, and Dagmar Heydeck, which appeared in issue 30, July 26, 2016, of Proc Natl Acad Sci USA (113:E4266–E4275; first published July 13, 2016; 10.1073/pnas.1604029113). The authors note that Table 5 appeared incorrectly. The corrected table appears below. The authors also note that on page E4266, in line 20 of the Abstract, “ratPhe353Ala” should instead appear as “ratLeu353Phe;” and that on page E4270, right column, first full paragraph, line 12, “ratPhe353Leu” should instead appear as “ratLeu353Phe.” These errors do not affect the conclusions of the article. Table 5. Relative lipoxin synthase activity of mammalian ALOX15 orthologs Relative lipoxin synthase activity, % 5-HETE as 5,6-DiHETE as Species 15-/12-ratio substrate substrate 15-lipoxygenating Human 8.1 100.0 100 Chimpanzee 8.1 118.0 145.8 Orangutan 8.1 172.2 105.6 Rabbit 24.0 39.5 108.6 ratL353F 13.3 197.3 262.5 Mean ± SD 12.3 ± 6.9 125.4 ± 62.1* 144.5 ± 68.4† 12-lipoxygenating Macaca 0.01 25.7 19.9 Mouse 0.03 36.1 1.5 Rat 0.26 8.4 0.0 Pig 0.04 35.4 61.1 humI418A 0.11 29.2 2.1 Mean ± SD 0.09 ± 0.10 27.0 ± 11.2* 17.1 ± 25.9† The relative lipoxin synthase activity of the ALOX15 orthologs was quantified as described in Materials and Methods. For 5S-HETE oxygenation, lipoxin A and lipoxin B isomers were quantified. During 5S,6(S/R)-DiHETE, only lipoxin A isomers were formed. *P = 0.008 by Student’s t test. †P = 0.005 by Student’s t test. www.pnas.org/cgi/doi/10.1073/pnas.1618183113 E8006 | PNAS | December 6, 2016 | vol. 113 | no. 49 www.pnas.org Downloaded by guest on September 25, 2021 Evolutionary alteration of ALOX15 specificity optimizes PNAS PLUS the biosynthesis of antiinflammatory and proresolving lipoxins Susan Adela,1, Felix Karsta,1, Àngels González-Lafontb,c, Mária Pekárováa,d, Patricia Saurab,c, Laura Masgrauc, José M. Lluchb,c, Sabine Stehlinga, Thomas Horna,2, Hartmut Kuhna,3, and Dagmar Heydecka aInstitute of Biochemistry, University Medicine Berlin–Charité, D-10117 Berlin, Germany; bDepartament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; cInstitut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; and dDepartment of Cell and Molecular Biology of Drugs, Faculty of Pharmacy, Comenius University, 832 32 Bratislava, Slovakia Edited by Klaus van Leyen, Harvard Medical School, Charlestown, MA, and accepted by Editorial Board Member Ruslan Medzhitov May 27, 2016 (received for review March 10, 2016) ALOX15 (12/15-lipoxygenase) orthologs have been implicated in Traditionally, mammalian LOXs have been classified according maturational degradation of intracellular organelles and in the to their reaction specificity with arachidonic acid into 5-LOX, 12- biosynthesis of antiinflammatory and proresolving eicosanoids. LOX, and 15-LOX, but this classification has several problems Here we hypothesized that lower mammals (mice, rats, pigs) (18). For those isoforms exhibiting their biological functions via express 12-lipoxygenating ALOX15 orthologs. In contrast, 15- the formation of bioactive mediators, the reaction specificity is of lipoxygenating isoforms are found in higher primates (orangutans, major biological importance. For instance, ALOX5 orthologs men), and these results suggest an evolution of ALOX15 specific- oxygenate arachidonic acid specifically to (6E,8Z,11Z,14Z)-5- ity. To test this hypothesis we first cloned and characterized hydroperoxy-6,8,11,14-eicosatetraenoic acid (5S-HpETE), which ALOX15 orthologs of selected Catarrhini representing different is further converted to various leukotrienes of the 5,6-series (4). stages of late primate evolution and found that higher pri- In contrast, 15-lipoxygenating LOX isoforms are not capable of mates (men, chimpanzees) express 15-lipoxygenating orthologs. In forming leukotrienes of the 5,6-series. Similarly, 12-lipoxygenating contrast, lower primates (baboons, rhesus monkeys) express 12- enzymes have been implicated in hepoxilin biosynthesis (5), but BIOCHEMISTRY lipoxygenating enzymes. Gibbons, which are flanked in evolution ALOX5 orthologs are not involved. by rhesus monkeys (12-lipoxygenating ALOX15) and orangutans Although mammalian ALOX15 orthologs have been known (15-lipoxygenating ALOX15), express an ALOX15 ortholog with for more than 40 y, their biological role is still a matter of dis- pronounced dual specificity. To explore the driving force for this cussion. The enzymes have been implicated in cell differentiation evolutionary alterations, we quantified the lipoxin synthase activity (6, 7) and in the pathogenesis of different diseases (1, 19), but of 12-lipoxygenating (rhesus monkey, mouse, rat, pig, humIle418Ala) there is no unifying concept for their functionality. Compared and 15-lipoxygenating (man, chimpanzee, orangutan, rabbit, with other LOX-isoforms, mammalian ALOX15 orthologs are ratPhe353Ala) ALOX15 variants and found that, when normalized to somewhat special. First, they are capable of oxygenating arachidonic their arachidonic acid oxygenase activities, the lipoxin synthase activities of 15-lipoxygenating ALOX15 variants were more than Significance fivefold higher (P < 0.01). Comparative molecular dynamics simula- tions and quantum mechanics/molecular mechanics calculations in- Lipoxygenases are lipid-peroxidizing enzymes that have been dicated that, for the 15-lipoxygenating rabbit ALOX15, the energy classified according to their reaction specificity. ALOX15 (12/15- barrier for C13-hydrogen abstraction (15-lipoxygenation) was 17 kJ/mol lipoxygenase) has been implicated in inflammatory resolution via lower than for arachidonic acid 12-lipoxygenation. In contrast, for biosynthesis of antiinflammatory and proresolving lipoxins. We the 12-lipoxygenating Ile418Ala mutant, the energy barrier for 15- found that lower mammals including lower primates express ara- lipoxygenation was 10 kJ/mol higher than for 12-lipoxygenation. chidonic acid 12-lipoxygenating ALOX15 orthologs, whereas higher Taken together, our data suggest an evolution of ALOX15 speci- primates express 15-lipoxygenating enzymes. Gibbons constitute ficity, which is aimed at optimizing the biosynthetic capacity for the missing link interconnecting 12- and 15-lipoxygenating ALOX15 antiinflammatory and proresolving lipoxins. orthologs. To explore the evolutionary driving force for this spec- ificity alteration, we quantified the lipoxin synthase activity of 12- eicosanoids | lipoxygenase | evolution | inflammation | protein design and 15-lipoxygenating ALOX15 orthologs and observed that the lipoxin synthase activities of 15-lipoxygenating enzymes were ipoxygenases (LOXs) form a diverse family of lipid-peroxidizing significantly higher. These results suggest an evolution of ALOX15 Lenzymes that catalyze the specific oxygenation of polyenoic specificity, which optimizes the biosynthetic capacity for antiin- fatty acids to their corresponding hydroperoxides (1, 2). Geno- flammatory and proresolving lipoxins. mic LOX sequences occur in two domains (Bacteria, Eukarya) of terrestrial life (3). In mammals, LOXs have been implicated in Author contributions: S.A., F.K., T.H., H.K., and D.H. designed research; S.A., F.K., À.G.-L., M.P., P.S., L.M., J.M.L., S.S., H.K., and D.H. performed research; S.A., F.K., À.G.-L., M.P., P.S., the biosynthesis of lipid mediators (4, 5), but they may also play a L.M., J.M.L., S.S., H.K., and D.H. analyzed data; and S.A., À.G.-L., T.H., H.K., and D.H. wrote role in cell differentiation (6, 7), apoptosis (8) and pathogenesis the paper. of inflammatory (9), hyperproliferative (10), and neurological (11) The authors declare no conflict of interest. disorders. Targeted gene inactivation in mice provided useful in- This article is a PNAS Direct Submission. K.v.L. is a guest editor invited by the Editorial formation on the functionality of Alox12B (12R-lipoxygenase) Board. 1 (12) and Aloxe3 (epidermal lipoxygenase-3) (13), but Alox5 (5- S.A. and F.K. contributed equally to this work. 2Present address: Institute of Biotechnology, RWTH Aachen University, 52074 Aachen, lipoxygenase)- (14), Alox15- (15), and Alox12-deficient mice (16) Germany. do not show major defects unless challenged otherwise. In the 3To whom correspondence should be addressed. Email: [email protected]. human genome, six functional LOX genes have been identified, This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10. which encode for six distinct LOX isoforms (17). 1073/pnas.1604029113/-/DCSupplemental. www.pnas.org/cgi/doi/10.1073/pnas.1604029113 PNAS Early Edition | 1of10 acid to 12-HpETE and 15-HpETE in variable amounts (20–22). logs of men (24), extinct human subspecies (25), various non- The molecular basis for this dual specificity has been explored human primates (22), rabbits (26), mice (27), rats (28), and pigs (23), and three critical amino acids have been identified (i.e., (29). Second, ALOX15 orthologs are capable of oxygenating “triad concept”). Alterations in the side-chain geometry of the phospholipids and cholesterol esters (30, 31), and thus, these LOX triad determinants impacted the specificity of ALOX15 ortho- isoforms can modify biomembranes and lipoproteins. Third, highly Fig. 1. Triad determinants of mammalian