Isolation and Characterization of Two Geometric Allene Oxide Isomers Synthesized from 9S-Hydroperoxylinoleic Acid by Cytochrome P450 CYP74C3

Specialized cytochromes P450 or catalase-related hemoproteins transform fatty acid hydroperoxides to allene oxides, highly reactive epoxides leading to cyclopentenones and other products. The stereochemistry of the natural allene oxides is incompletely defined, as are the structural features required for their cyclization. We investigated the transformation of 9S-hydroperoxylinoleic acid with the allene oxide synthase CYP74C3, a reported reaction that unexpectedly produces an allene oxide-derived cyclopentenone. Using biphasic reaction conditions at 0 °C, we isolated the initial products and separated two allene oxide isomers by HPLC at −15 °C. One matched previously described allene oxides in its UV spectrum (λmax 236 nm) and NMR spectrum (defining a 9,10-epoxy-octadec-10,12Z-dienoate). The second was a novel stereoisomer (UV λmax 239 nm) with distinctive NMR chemical shifts. Comparison of NOE interactions of the epoxy proton at C9 in the two allene oxides (and the equivalent NOE experiment in 12,13-epoxy allene oxides) allowed assignment at the isomeric C10 epoxy-ene carbon as Z in the new isomer and the E configuration in all previously characterized allene oxides. The novel 10Z isomer spontaneously formed a cis-cyclopentenone at room temperature in hexane. These results explain the origin of the cyclopentenone, provide insights into the mechanisms of allene oxide cyclization, and define the double bond geometry in naturally occurring allene oxides.

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Detection of the First Epoxyalcohol Synthase/Allene Oxide Synthase (CYP74 Clan) in the Lancelet (Branchiostoma belcheri, Chordata)

International Journal of Molecular Sciences ◽

10.3390/ijms22094737 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4737

Author(s):

Yana Y. Toporkova ◽

Elena O. Smirnova ◽

Natalia V. Lantsova ◽

Lucia S. Mukhtarova ◽

Alexander N. Grechkin

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Oxidative Metabolism ◽

Octadecadienoic Acid ◽

Cytochromes P450 ◽

Allene Oxide ◽

Allene Oxide Synthase ◽

Branchiostoma Belcheri ◽

Oxide Synthase ◽

Fatty Acid Hydroperoxides

The CYP74 clan cytochromes (P450) are key enzymes of oxidative metabolism of polyunsaturated fatty acids in plants, some Proteobacteria, brown and green algae, and Metazoa. The CYP74 enzymes, including the allene oxide synthases (AOSs), hydroperoxide lyases, divinyl ether synthases, and epoxyalcohol synthases (EASs) transform the fatty acid hydroperoxides to bioactive oxylipins. A novel CYP74 clan enzyme CYP440A18 of the Asian (Belcher’s) lancelet (Branchiostoma belcheri, Chordata) was biochemically characterized in the present work. The recombinant CYP440A18 enzyme was active towards all substrates used: linoleate and α-linolenate 9- and 13-hydroperoxides, as well as with eicosatetraenoate and eicosapentaenoate 15-hydroperoxides. The enzyme specifically converted α-linolenate 13-hydroperoxide (13-HPOT) to the oxiranyl carbinol (9Z,11R,12R,13S,15Z)-11-hydroxy-12,13-epoxy-9,15-octadecadienoic acid (EAS product), α-ketol, 12-oxo-13-hydroxy-9,15-octadecadienoic acid (AOS product), and cis-12-oxo-10,15-phytodienoic acid (AOS product) at a ratio of around 35:5:1. Other hydroperoxides were converted by this enzyme to the analogous products. In contrast to other substrates, the 13-HPOT and 15-HPEPE yielded higher proportions of α-ketols, as well as the small amounts of cyclopentenones, cis-12-oxo-10,15-phytodienoic acid and its higher homologue, dihomo-cis-12-oxo-3,6,10,15-phytotetraenoic acid, respectively. Thus, the CYP440A18 enzyme exhibited dual EAS/AOS activity. The obtained results allowed us to ascribe a name “B. belcheri EAS/AOS” (BbEAS/AOS) to this enzyme. BbEAS/AOS is a first CYP74 clan enzyme of Chordata species possessing AOS activity.

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Chemistry of singlet oxygen: Isolation and characterization of a stable allene oxide from a fulvene endoperoxide

Tetrahedron Letters ◽

10.1016/s0040-4039(00)91767-2 ◽

1993 ◽

Vol 34 (8) ◽

pp. 1255-1258 ◽

Cited By ~ 21

Author(s):

Ihsan Erden ◽

Jane Drummond ◽

Roger Alstad ◽

Fupei Xu

Keyword(s):

Singlet Oxygen ◽

Allene Oxide ◽

Isolation And Characterization

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Specific Adduction of Plant Lipid Transfer Protein by an Allene Oxide Generated by 9-Lipoxygenase and Allene Oxide Synthase

Journal of Biological Chemistry ◽

10.1074/jbc.m608580200 ◽

2006 ◽

Vol 281 (51) ◽

pp. 38981-38988 ◽

Cited By ~ 31

Author(s):

Bénédicte Bakan ◽

Mats Hamberg ◽

Ludivine Perrocheau ◽

Daniel Maume ◽

Hélène Rogniaux ◽

...

Keyword(s):

Lipid Transfer Protein ◽

Allene Oxide ◽

Allene Oxide Synthase ◽

Lipid Transfer ◽

Plant Lipid ◽

Transfer Protein ◽

Oxide Synthase

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Functional Characterization of An Allene Oxide Synthase Involved in Biosynthesis of Jasmonic Acid and Its Influence on Metabolite Profiles and Ethylene Formation in Tea (Camellia sinensis) Flowers

International Journal of Molecular Sciences ◽

10.3390/ijms19082440 ◽

2018 ◽

Vol 19 (8) ◽

pp. 2440 ◽

Cited By ~ 5

Author(s):

Qiyuan Peng ◽

Ying Zhou ◽

Yinyin Liao ◽

Lanting Zeng ◽

Xinlan Xu ◽

...

Keyword(s):

Mass Spectrometry ◽

Jasmonic Acid ◽

Camellia Sinensis ◽

Allene Oxide ◽

Allene Oxide Synthase ◽

Tea Leaves ◽

Ethylene Formation ◽

Horticultural Crops ◽

Metabolite Profiles ◽

Oxide Synthase

Jasmonic acid (JA) is reportedly involved in the interaction between insects and the vegetative parts of horticultural crops; less attention has, however, been paid to its involvement in the interaction between insects and the floral parts of horticultural crops. Previously, we investigated the allene oxide synthase 2 (AOS2) gene that was found to be the only JA synthesis gene upregulated in tea (Camellia sinensis) flowers exposed to insect (Thrips hawaiiensis (Morgan)) attacks. In our present study, transient expression analysis in Nicotiana benthamiana plants confirmed that CsAOS2 functioned in JA synthesis and was located in the chloroplast membrane. In contrast to tea leaves, the metabolite profiles of tea flowers were not significantly affected by 10 h JA (2.5 mM) treatment as determined using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry, and gas chromatography-mass spectrometry. Moreover, JA treatment did not significantly influence ethylene formation in tea flowers. These results suggest that JA in tea flowers may have different functions from JA in tea leaves and other flowers.

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Molecular cloning of an allene oxide synthase: a cytochrome P450 specialized for the metabolism of fatty acid hydroperoxides.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.90.18.8519 ◽

1993 ◽

Vol 90 (18) ◽

pp. 8519-8523 ◽

Cited By ~ 190

Author(s):

W. C. Song ◽

C. D. Funk ◽

A. R. Brash

Keyword(s):

Cytochrome P450 ◽

Fatty Acid ◽

Molecular Cloning ◽

Allene Oxide ◽

Allene Oxide Synthase ◽

Oxide Synthase ◽

Fatty Acid Hydroperoxides

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Isolation and characterization of some novel genes of the apolipoprotein A-I family in Japanese eel, Anguilla japonica

Open Life Sciences ◽

10.2478/s11535-011-0042-8 ◽

2011 ◽

Vol 6 (4) ◽

pp. 545-557 ◽

Cited By ~ 2

Author(s):

Malay Choudhury ◽

Takahiro Oku ◽

Shoji Yamada ◽

Masaharu Komatsu ◽

Keita Kudoh ◽

...

Keyword(s):

Amino Acids ◽

Molecular Weight ◽

Amino Acid ◽

Consensus Sequence ◽

Structural Features ◽

Lipid Binding ◽

Japanese Eel ◽

Amino Acid Sequences ◽

Novel Genes ◽

Isolation And Characterization

AbstractApolipoproteins such as apolipoprotein (apo) A-I, apoA-IV, and apoE are lipid binding proteins synthesized mainly in the liver and the intestine and play an important role in the transfer of exogenous or endogenous lipids through the circulatory system. To investigate the mechanism of lipid transport in fish, we have isolated some novel genes of the apoA-I family, apoIA-I (apoA-I isoform) 1–11, from Japanese eel by PCR amplification. Some of the isolated genes of apoIA-I corresponded to 28kDa-1 cDNAs which had already been deposited into the database and encoded an apolipoprotein with molecular weight of 28 kDa in the LDL, whereas others seemed to be novel genes. The structural organization of all apoIA-Is consisted of four exons separated by three introns. ApoIA-I10 had a total length of 3232 bp, whereas other genes except for apoIA-I9 ranged from 1280 to 1441 bp. The sequences of apoIA-Is at the exon-intron junctions were mostly consistent with the consensus sequence (GT/AG) at exon-intron boundaries, whereas the sequences of 3′ splice acceptor in intron 1 of apoIA-I1-7 were (AC) but not (AG). The deduced amino acid sequences of all apoIA-Is contained a putative signal peptide and a propeptide of 17 and 5 amino acid residues, respectively. The mature proteins of apoIA-I1-3, 7, and 8 consisted of 237 amino acids, whereas those of apoIA-I4-6 consisted of 239 amino acids. The mature apoIA-I10 sequence showed 65% identity to amino acid sequence of apoIA-I11 which was associated with an apolipoprotein with molecular weight of 23 kDa in the VLDL. All these mature apoIA-I sequences satisfied the common structural features depicted for the exchangeable apolipoproteins such as apoA-I, apoA-IV, and apoE but apoIA-I11 lacked internal repeats 7, 8, and 9 when compared with other members of apoA-I family. Phylogenetic analysis showed that these novel apoIA-Is isolated from Japanese eel were much closer to apoA-I than apoA-IV and apoE, suggesting new members of the apoA-I family.

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A density functional approach toward structural features and properties of C20…N2X2 (X = H, F, Cl, Br, Me) molecules

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633614500230 ◽

2014 ◽

Vol 13 (04) ◽

pp. 1450023 ◽

Cited By ~ 4

Author(s):

Reza Ghiasi ◽

Morteza Zaman Fashami ◽

Amir Hossein Hakimioun

Keyword(s):

Density Functional ◽

Chemical Shifts ◽

Geometry Optimization ◽

Structural Features ◽

Nbo Analysis ◽

Basis Set ◽

Basis Sets ◽

Basis Set Superposition Error ◽

Homo And Lumo ◽

Lowest Unoccupied Molecular Orbitals

In this work, the interaction of C 20 with N 2 X 2 ( X = H , F , Cl , Br , Me ) molecules has been explored using the B3LYP, M062x methods and 6-311G(d,p) and 6-311+G(d,p) basis sets. The interaction energies (IEs) obtained with standard method were corrected by basis set superposition error (BSSE) during the geometry optimization for all molecules at the same levels of theory. It was found C 20… N 2 H 2 interaction is stronger than the interaction of other N 2 X 2 ( X = F , Cl , Br , Me ) with C 20. Highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO, respectively) levels are illustrated by density of states spectra (DOS). The nucleus-independent chemical shifts (NICSs) confirm that C 20… N 2 X 2 molecules exhibit aromatic characteristics. Geometries obtained from DFT calculations were used to perform NBO analysis. Also, 14 N NQR parameters of the C 20… N 2 X 2 molecules are predicted.

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Isolation and characterization of PKC-L, a new member of the protein kinase C-related gene family specifically expressed in lung, skin, and heart

Molecular and Cellular Biology ◽

10.1128/mcb.11.1.126-133.1991 ◽

1991 ◽

Vol 11 (1) ◽

pp. 126-133 ◽

Cited By ~ 1

Author(s):

N Bacher ◽

Y Zisman ◽

E Berent ◽

E Livneh

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Gene Family ◽

Phorbol Esters ◽

Structural Features ◽

Cos Cells ◽

Isolation And Characterization ◽

Kinase C ◽

Human Epidermoid Carcinoma

We have isolated and characterized a new human cDNA, coding for a protein kinase, related to the protein kinase C (PKC) gene family. Although this protein kinase shares some homologous sequences and structural features with the four members of the PKC family initially isolated (alpha, beta I, beta II, and gamma), it shows more homology with the recently described PKC-related subfamily, encoded by the cDNAs delta, epsilon, and zeta. The transcript for this gene product, termed PKC-L, is most abundant in lung tissue, less expressed in heart and skin tissue, and exhibited very low expression in brain tissue. Thus, its tissue distribution is different from that described for other mammalian members of the PKC gene family, their expression being enriched in brain tissues. PKC-L is also expressed in several human cell lines, including the human epidermoid carcinoma line A431. The ability of phorbol esters to bind to and stimulate the kinase activity of PKC-L was revealed by introducing the cDNA into COS cells.

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