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[PMID]:29225126
[Au] Autor:Xu J; Xu J; Ai Y; Farid RA; Tong L; Yang D
[Ad] Endereço:Gene Engineering and Biotechnology Beijing Key Laboratory, College of Life Sciences, Beijing Normal University, Beijing 100875 China.
[Ti] Título:Mutational analysis and dynamic simulation of S-limonene synthase reveal the importance of Y573: Insight into the cyclization mechanism in monoterpene synthases.
[So] Source:Arch Biochem Biophys;638:27-34, 2018 01 15.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Monoterpene synthases carry out complex reactions to produce multiple products from a sole substrate, geranyl pyrophosphate (GPP). S-limonene synthase (LS) is a model monoterpene synthase that can be explored to understand the catalytic mechanism of these enzymes. In this study, we have identified an active site tyrosine residue (Y573) is crucial for the enzyme activity and mutational analysis indicates that both the aromatic ring and hydroxyl group are essential for the catalysis. Dynamic simulations found a hydrogen bond between Y573 and D496 and also a significant conformational change in the helical form of the LPP intermediate. Further mutagenesis suggested that this hydrogen bond is essential for catalysis. Sequence analysis suggested Y573 is completely conserved among cyclic monoterpene synthases but variable in acyclic enzymes, indicating this residue may be involved in cyclization. Subsequent studies by using neryl diphosphate (NPP) as the substrate ruled out the possibility that Y573 functions solely at the substrate isomerization step. Therefore, a more complicated role may be played by this residue. We proposed that Y573 may be involved in the earlier steps of the reaction, probably by controlling the conformation of the helical LPP intermediate. Our study provides important insights not only on the catalytic mechanism of LS, but also on the cyclization of monoterpene synthases in general.
[Mh] Termos MeSH primário: Liases Intramoleculares
Simulação de Dinâmica Molecular
Mutação de Sentido Incorreto
Pinaceae
Proteínas de Plantas
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Liases Intramoleculares/química
Liases Intramoleculares/genética
Mutagênese
Pinaceae/enzimologia
Pinaceae/genética
Proteínas de Plantas/química
Proteínas de Plantas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Plant Proteins); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (pinene cyclase I)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171212
[St] Status:MEDLINE


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[PMID]:28841019
[Au] Autor:Christianson DW
[Ad] Endereço:Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania , 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States.
[Ti] Título:Structural and Chemical Biology of Terpenoid Cyclases.
[So] Source:Chem Rev;117(17):11570-11648, 2017 Sep 13.
[Is] ISSN:1520-6890
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The year 2017 marks the twentieth anniversary of terpenoid cyclase structural biology: a trio of terpenoid cyclase structures reported together in 1997 were the first to set the foundation for understanding the enzymes largely responsible for the exquisite chemodiversity of more than 80000 terpenoid natural products. Terpenoid cyclases catalyze the most complex chemical reactions in biology, in that more than half of the substrate carbon atoms undergo changes in bonding and hybridization during a single enzyme-catalyzed cyclization reaction. The past two decades have witnessed structural, functional, and computational studies illuminating the modes of substrate activation that initiate the cyclization cascade, the management and manipulation of high-energy carbocation intermediates that propagate the cyclization cascade, and the chemical strategies that terminate the cyclization cascade. The role of the terpenoid cyclase as a template for catalysis is paramount to its function, and protein engineering can be used to reprogram the cyclization cascade to generate alternative and commercially important products. Here, I review key advances in terpenoid cyclase structural and chemical biology, focusing mainly on terpenoid cyclases and related prenyltransferases for which X-ray crystal structures have informed and advanced our understanding of enzyme structure and function.
[Mh] Termos MeSH primário: Alquil e Aril Transferases/química
Terpenos/metabolismo
[Mh] Termos MeSH secundário: Alquil e Aril Transferases/metabolismo
Carbono-Carbono Liases/química
Carbono-Carbono Liases/metabolismo
Cristalografia por Raios X
Dimetilaliltranstransferase/química
Dimetilaliltranstransferase/metabolismo
Liases Intramoleculares/química
Liases Intramoleculares/metabolismo
Estrutura Terciária de Proteína
Terpenos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Terpenes); EC 2.5.- (Alkyl and Aryl Transferases); EC 2.5.1.- (terpene carbocyclase); EC 2.5.1.1 (Dimethylallyltranstransferase); EC 4.1.- (Carbon-Carbon Lyases); EC 4.2.3.6 (trichodiene synthetase); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (pinene cyclase I)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170826
[St] Status:MEDLINE
[do] DOI:10.1021/acs.chemrev.7b00287


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[PMID]:28675805
[Au] Autor:Lazarus S; Tseng HW; Lawrence F; Woodruff MA; Duncan EL; Pettit AR
[Ad] Endereço:Translational Research Institute, Brisbane, Queensland, Australia; University of Queensland Diamantina Institute, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia; Department of Endocrinology and Diabetes, Royal Brisbane and Women's Hospital, Brisbane, Queensland, A
[Ti] Título:Characterization of Normal Murine Carpal Bone Development Prompts Re-Evaluation of Pathologic Osteolysis as the Cause of Human Carpal-Tarsal Osteolysis Disorders.
[So] Source:Am J Pathol;187(9):1923-1934, 2017 Sep.
[Is] ISSN:1525-2191
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Multicentric carpal-tarsal osteolysis; multicentric osteolysis, nodulosis, and arthropathy; and Winchester syndromes, skeletal dysplasias characterized by carpal/tarsal and epiphyseal abnormalities, are caused by mutations in v-maf musculoaponeurotic fibrosarcoma oncogene ortholog B (MAFB), matrix metalloproteinase (MMP) 2, and MMP14, respectively; however, the underlying pathophysiology is unclear. Osteoclast-mediated osteolysis has been regarded as the main mechanism, but does not explain the skeletal distribution. We hypothesized that MAFB, MMP-2, and MMP-14 have integral roles in carpal/tarsal and epiphyseal bone development. Normal neonatal mouse forepaws were imaged by micro-computed tomography and examined histologically. Murine forepaw ossification occurred sequentially. Subarticular regions of endochondral ossification showed morphologic and calcification patterns that were distinct from archetypical physeal endochondral ossification. This suggests that two different forms of endochondral ossification occur. The skeletal sites showing the greatest abnormality in the carpal-tarsal osteolysis syndromes are regions of subarticular ossification. Thus, abnormal bone formation in areas of subarticular ossification may explain the site-specific distribution of the carpal-tarsal osteolysis phenotype. MafB, Mmp-2, and Mmp-14 were expressed widely, and tartrate-resistant acid phosphatase staining notably was absent in the subarticular regions of the cartilage anlagen and entheses at a time point most relevant to the human osteolysis syndromes. Thus, abnormal peri-articular skeletal development and modeling, rather than excessive bone resorption, may be the underlying pathophysiology of these skeletal syndromes.
[Mh] Termos MeSH primário: Ossos do Carpo/crescimento & desenvolvimento
Lâmina de Crescimento/patologia
Osteólise/patologia
[Mh] Termos MeSH secundário: Animais
Proteínas de Arabidopsis
Ossos do Carpo/diagnóstico por imagem
Ossos do Carpo/metabolismo
Pré-Escolar
Lâmina de Crescimento/diagnóstico por imagem
Lâmina de Crescimento/metabolismo
Seres Humanos
Liases Intramoleculares
Fator de Transcrição MafB/metabolismo
Metaloproteinase 14 da Matriz/metabolismo
Metaloproteinase 2 da Matriz/metabolismo
Camundongos
Osteogênese
Osteólise/diagnóstico por imagem
Osteólise/metabolismo
Microtomografia por Raio-X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Arabidopsis Proteins); 0 (MafB Transcription Factor); 0 (Mafb protein, mouse); EC 3.4.24.24 (Matrix Metalloproteinase 2); EC 3.4.24.80 (Matrix Metalloproteinase 14); EC 5.5.- (Intramolecular Lyases); EC 5.5.1.6 (CHIL protein, Arabidopsis)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170914
[Lr] Data última revisão:
170914
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170705
[St] Status:MEDLINE


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[PMID]:28655616
[Au] Autor:Hurd MC; Kwon M; Ro DK
[Ad] Endereço:University of Calgary, Department of Biological Sciences, Calgary, AB, T2N 1N4, Canada.
[Ti] Título:Functional identification of a Lippia dulcis bornyl diphosphate synthase that contains a duplicated, inhibitory arginine-rich motif.
[So] Source:Biochem Biophys Res Commun;490(3):963-968, 2017 Aug 26.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Lippia dulcis (Aztec sweet herb) contains the potent natural sweetener hernandulcin, a sesquiterpene ketone found in the leaves and flowers. Utilizing the leaves for agricultural application is challenging due to the presence of the bitter-tasting and toxic monoterpene, camphor. To unlock the commercial potential of L. dulcis leaves, the first step of camphor biosynthesis by a bornyl diphosphate synthase needs to be elucidated. Two putative monoterpene synthases (LdTPS3 and LdTPS9) were isolated from L. dulcis leaf cDNA. To elucidate their catalytic functions, E. coli-produced recombinant enzymes with truncations of their chloroplast transit peptides were assayed with geranyl diphosphate (GPP). In vitro enzyme assays showed that LdTPS3 encodes bornyl diphosphate synthase (thus named LdBPPS) while LdTPS9 encodes linalool synthase. Interestingly, the N-terminus of LdBPPS possesses two arginine-rich (RRX W) motifs, and enzyme assays showed that the presence of both RRX W motifs completely inhibits the catalytic activity of LdBPPS. Only after the removal of the putative chloroplast transit peptide and the first RRX W, LdBPPS could react with GPP to produce bornyl diphosphate. LdBPPS is distantly related to the known bornyl diphosphate synthase from sage in a phylogenetic analysis, indicating a converged evolution of camphor biosynthesis in sage and L. dulcis. The discovery of LdBPPS opens up the possibility of engineering L. dulcis to remove the undesirable product, camphor.
[Mh] Termos MeSH primário: Cânfora/metabolismo
Liases Intramoleculares/metabolismo
Lippia/enzimologia
Sesquiterpenos/metabolismo
[Mh] Termos MeSH secundário: Motivos de Aminoácidos
Sequência de Aminoácidos
Arginina/química
Arginina/metabolismo
Liases Intramoleculares/química
Liases Intramoleculares/genética
Lippia/química
Lippia/genética
Lippia/metabolismo
Filogenia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Sesquiterpenes); 76-22-2 (Camphor); 7V22TJL7NX (hernandulcin); 94ZLA3W45F (Arginine); EC 5.5.- (Intramolecular Lyases); EC 5.5.1.8 (geranyl-diphosphate cyclase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170629
[St] Status:MEDLINE


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[PMID]:28550743
[Au] Autor:Radwan A; Kleinwächter M; Selmar D
[Ad] Endereço:Technische Universität Braunschweig, Institute for Plant Biology, Mendelssohnstr. 4, 38106, Braunschweig, Germany; Agriculture Genetic Engineering Research Institute, AGERI, ARC, Giza, Egypt.
[Ti] Título:Impact of drought stress on specialised metabolism: Biosynthesis and the expression of monoterpene synthases in sage (Salvia officinalis).
[So] Source:Phytochemistry;141:20-26, 2017 Sep.
[Is] ISSN:1873-3700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In previous experiments, we demonstrated that the amount of monoterpenes in sage is increased massively by drought stress. Our current study is aimed to elucidate whether this increase is due, at least in part, to elevated activity of the monoterpene synthases responsible for the biosynthesis of essential oils in sage. Accordingly, the transcription rates of the monoterpene synthases were analyzed. Salvia officinalis plants were cultivated under moderate drought stress. The concentrations of monoterpenes as well as the expression of the monoterpene synthases were analyzed. The amount of monoterpenes massively increased in response to drought stress; it doubled after just two days of drought stress. The observed changes in monoterpene content mostly match with the patterns of monoterpene synthase expressions. The expression of bornyl diphosphate synthase was strongly up-regulated; its maximum level was reached after two days. Sabinene synthase increased gradually and reached a maximum after two weeks. In contrast, the transcript level of cineole synthase continuously declined. This study revealed that the stress related increase of biosynthesis is not only due to a "passive" shift caused by the stress related over-reduced status, but also is due - at least in part-to an "active" up-regulation of the enzymes involved.
[Mh] Termos MeSH primário: Secas
Liases Intramoleculares/metabolismo
Salvia officinalis/enzimologia
Estresse Fisiológico
[Mh] Termos MeSH secundário: Regulação da Expressão Gênica de Plantas
Liases Intramoleculares/genética
Monoterpenos/metabolismo
Óleos Voláteis/metabolismo
Salvia officinalis/genética
Regulação para Cima
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Monoterpenes); 0 (Oils, Volatile); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (pinene cyclase I); EC 5.5.1.8 (geranyl-diphosphate cyclase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170721
[Lr] Data última revisão:
170721
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170528
[St] Status:MEDLINE


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[PMID]:28371918
[Au] Autor:Sugiyama K; Ebisawa M; Yamada M; Nagashima Y; Suzuki H; Maoka T; Takaichi S
[Ad] Endereço:Department of Applied Chemistry, Kogakuin University, Hachioji, Japan.
[Ti] Título:Functional Lycopene Cyclase (CruA) in Cyanobacterium, Arthrospira platensis NIES-39, and its Role in Carotenoid Synthesis.
[So] Source:Plant Cell Physiol;58(4):831-838, 2017 04 01.
[Is] ISSN:1471-9053
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:The genus Arthrospira is filamentous, non-nitrogen-fixing cyanobacteria that is commercially important. We identified the molecular structures of carotenoids in Arthrospira platensis NIES-39. The major carotenoid identified was ß-carotene. In addition, the hydroxyl derivatives of ß-cryptoxanthin and (3R,3'R)-zeaxanthin were also found to be present. The carotenoid glycosides were identified as (3R,2'S)-myxol 2'-methylpentoside and oscillol 2,2'-dimethylpentoside. The methylpentoside moiety was a mixture of fucoside and chinovoside in an approximate ratio of 1 : 4. Trace amounts of the ketocarotenoid 3'-hydroxyechinenone were also found. Three types of lycopene cyclases have been functionally confirmed in carotenogenesis organisms. In cyanobacteria, the functional lycopene cyclases (CrtL, CruA and CruP) have only been found in four species. In this study, we found that CruA exhibited lycopene cyclase activity in transformed Escherichia coli, which contains lycopene, but CruP exhibited no lycopene cyclase activity and crtL was absent. This is the third cyanobacterial species in which CruA activity has been confirmed. Neurosporene was not a substrate of CruA in E. coli, whereas lycopene cyclases of CrtY (bacteria), CrtL (plants) and CrtYB (fungi) have been reported to convert neurosporene to 7,8-dihydro-ß-carotene. ß-Carotene hydroxylase (CrtR) was found to convert ß-carotene to zeaxanthin in transformed E. coli, which contains ß-carotene. Among the ß-carotene hydroxylases, bacterial CrtZ and eukaryotic CrtR and BCH have similarities, whereas cyanobacterial CrtR appears to belong to another clade. Based on the identification of the carotenoids and the completion of the entire nucleotide sequence of the A. platensis NIES-39 genome, we propose a biosynthetic pathway for the carotenoids as well as the corresponding genes and enzymes.
[Mh] Termos MeSH primário: Carotenoides/biossíntese
Liases Intramoleculares/metabolismo
Oxigenases de Função Mista/metabolismo
Spirulina/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Carotenoides/metabolismo
Clonagem Molecular
Escherichia coli/genética
Liases Intramoleculares/genética
Oxigenases de Função Mista/genética
Zeaxantinas/metabolismo
beta Caroteno/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Zeaxanthins); 01YAE03M7J (beta Carotene); 36-88-4 (Carotenoids); EC 1.- (Mixed Function Oxygenases); EC 1.14.13.- (beta-carotene hydroxylase); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (lycopene cyclase-isomerase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170404
[St] Status:MEDLINE
[do] DOI:10.1093/pcp/pcx015


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[PMID]:28272876
[Au] Autor:Kumar RP; Morehouse BR; Matos JO; Malik K; Lin H; Krauss IJ; Oprian DD
[Ad] Endereço:Department of Biochemistry, Brandeis University , Waltham, Massachusetts 02454, United States.
[Ti] Título:Structural Characterization of Early Michaelis Complexes in the Reaction Catalyzed by (+)-Limonene Synthase from Citrus sinensis Using Fluorinated Substrate Analogues.
[So] Source:Biochemistry;56(12):1716-1725, 2017 Mar 28.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The stereochemical course of monoterpene synthase reactions is thought to be determined early in the reaction sequence by selective binding of distinct conformations of the geranyl diphosphate (GPP) substrate. We explore here formation of early Michaelis complexes of the (+)-limonene synthase [(+)-LS] from Citrus sinensis using monofluorinated substrate analogues 2-fluoro-GPP (FGPP) and 2-fluoroneryl diphosphate (FNPP). Both are competitive inhibitors for (+)-LS with K values of 2.4 ± 0.5 and 39.5 ± 5.2 µM, respectively. The K values are similar to the K for the respective nonfluorinated substrates, indicating that fluorine does not significantly perturb binding of the ligand to the enzyme. FGPP and FNPP are also substrates, but with dramatically reduced rates (k values of 0.00054 ± 0.00005 and 0.00024 ± 0.00002 s , respectively). These data are consistent with a stepwise mechanism for (+)-LS involving ionization of the allylic GPP substrate to generate a resonance-stabilized carbenium ion in the rate-limiting step. Crystals of apo-(+)-LS were soaked with FGPP and FNPP to obtain X-ray structures at 2.4 and 2.2 Å resolution, respectively. The fluorinated analogues are found anchored in the active site through extensive interactions involving the diphosphate, three metal ions, and three active-site Asp residues. Electron density for the carbon chains extends deep into a hydrophobic pocket, while the enzyme remains mostly in the open conformation observed for the apoprotein. While FNPP was found in multiple conformations, FGPP, importantly, was in a single, relatively well-defined, left-handed screw conformation, consistent with predictions for the mechanism of stereoselectivity in the monoterpene synthases.
[Mh] Termos MeSH primário: Apoproteínas/química
Citrus sinensis/química
Cicloexenos/química
Diterpenos/química
Inibidores Enzimáticos/química
Liases Intramoleculares/química
Organofosfatos/química
Proteínas de Plantas/química
Terpenos/química
[Mh] Termos MeSH secundário: Apoproteínas/antagonistas & inibidores
Apoproteínas/genética
Apoproteínas/metabolismo
Domínio Catalítico
Citrus sinensis/enzimologia
Clonagem Molecular
Cristalografia por Raios X
Cicloexenos/metabolismo
Diterpenos/metabolismo
Ensaios Enzimáticos
Inibidores Enzimáticos/metabolismo
Escherichia coli/genética
Escherichia coli/metabolismo
Expressão Gênica
Liases Intramoleculares/antagonistas & inibidores
Liases Intramoleculares/genética
Liases Intramoleculares/metabolismo
Cinética
Ligantes
Modelos Moleculares
Organofosfatos/metabolismo
Proteínas de Plantas/antagonistas & inibidores
Proteínas de Plantas/genética
Proteínas de Plantas/metabolismo
Fosfatos de Poli-Isoprenil/química
Fosfatos de Poli-Isoprenil/metabolismo
Domínios Proteicos
Estrutura Secundária de Proteína
Proteínas Recombinantes de Fusão/química
Proteínas Recombinantes de Fusão/genética
Proteínas Recombinantes de Fusão/metabolismo
Estereoisomerismo
Terpenos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (2-fluorogeranylgeranyl diphosphate); 0 (Apoproteins); 0 (Cyclohexenes); 0 (Diterpenes); 0 (Enzyme Inhibitors); 0 (Ligands); 0 (Organophosphates); 0 (Plant Proteins); 0 (Polyisoprenyl Phosphates); 0 (Recombinant Fusion Proteins); 0 (Terpenes); 9MC3I34447 (limonene); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (pinene cyclase I); N21T0D88LX (geranylgeranyl pyrophosphate)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170309
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00144


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[PMID]:28272875
[Au] Autor:Morehouse BR; Kumar RP; Matos JO; Olsen SN; Entova S; Oprian DD
[Ad] Endereço:Department of Biochemistry, Brandeis University , Waltham, Massachusetts 02454, United States.
[Ti] Título:Functional and Structural Characterization of a (+)-Limonene Synthase from Citrus sinensis.
[So] Source:Biochemistry;56(12):1706-1715, 2017 Mar 28.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Terpenes make up the largest and most diverse class of natural compounds and have important commercial and medical applications. Limonene is a cyclic monoterpene (C ) present in nature as two enantiomers, (+) and (-), which are produced by different enzymes. The mechanism of production of the (-)-enantiomer has been studied in great detail, but to understand how enantiomeric selectivity is achieved in this class of enzymes, it is important to develop a thorough biochemical description of enzymes that generate (+)-limonene, as well. Here we report the first cloning and biochemical characterization of a (+)-limonene synthase from navel orange (Citrus sinensis). The enzyme obeys classical Michaelis-Menten kinetics and produces exclusively the (+)-enantiomer. We have determined the crystal structure of the apoprotein in an "open" conformation at 2.3 Å resolution. Comparison with the structure of (-)-limonene synthase (Mentha spicata), which is representative of a fully closed conformation (Protein Data Bank entry 2ONG ), reveals that the short H-α1 helix moves nearly 5 Å inward upon substrate binding, and a conserved Tyr flips to point its hydroxyl group into the active site.
[Mh] Termos MeSH primário: Apoproteínas/química
Citrus sinensis/química
Cicloexenos/química
Liases Intramoleculares/química
Proteínas de Plantas/química
Proteínas Recombinantes de Fusão/química
Terpenos/química
[Mh] Termos MeSH secundário: Apoproteínas/genética
Apoproteínas/metabolismo
Domínio Catalítico
Citrus sinensis/enzimologia
Clonagem Molecular
Cristalografia por Raios X
Cicloexenos/metabolismo
Difosfatos/química
Difosfatos/metabolismo
Diterpenos/química
Diterpenos/metabolismo
Ensaios Enzimáticos
Escherichia coli/genética
Escherichia coli/metabolismo
Expressão Gênica
Liases Intramoleculares/genética
Liases Intramoleculares/metabolismo
Cinética
Mentha spicata/química
Mentha spicata/enzimologia
Modelos Moleculares
Mutagênese Sítio-Dirigida
Mutação
Proteínas de Plantas/genética
Proteínas de Plantas/metabolismo
Domínios Proteicos
Estrutura Secundária de Proteína
Proteínas Recombinantes de Fusão/genética
Proteínas Recombinantes de Fusão/metabolismo
Estereoisomerismo
Terpenos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Apoproteins); 0 (Cyclohexenes); 0 (Diphosphates); 0 (Diterpenes); 0 (Plant Proteins); 0 (Recombinant Fusion Proteins); 0 (Terpenes); 0 (geranyl diphosphate); 9MC3I34447 (limonene); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (pinene cyclase I)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170309
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00143


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[PMID]:28215610
[Au] Autor:Xu J; Ai Y; Wang J; Xu J; Zhang Y; Yang D
[Ad] Endereço:Gene Engineering and Biotechnology Beijing Key Laboratory, College of Life Sciences, Beijing Normal University, Beijing, 100875 China.
[Ti] Título:Converting S-limonene synthase to pinene or phellandrene synthases reveals the plasticity of the active site.
[So] Source:Phytochemistry;137:34-41, 2017 May.
[Is] ISSN:1873-3700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:S-limonene synthase is a model monoterpene synthase that cyclizes geranyl pyrophosphate (GPP) to form S-limonene. It is a relatively specific enzyme as the majority of its products are composed of limonene. In this study, we converted it to pinene or phellandrene synthases after introducing N345A/L423A/S454A or N345I mutations. Further studies on N345 suggest the polarity of this residue plays a critical role in limonene production by stabilizing the terpinyl cation intermediate. If it is mutated to a non-polar residue, further cyclization or hydride shifts occurs so the carbocation migrates towards the pyrophosphate, leading to the production of pinene or phellandrene. On the other hand, mutant enzymes that still possess a polar residue at this position produce limonene as the major product. N345 is not the only polar residue that may stabilize the terpinyl cation because it is not strictly conserved among limonene synthases across species and there are also several other polar residues in this area. These residues could form a "polar pocket" that may collectively play this stabilizing role. Our study provides important insights into the catalytic mechanism of limonene synthases. Furthermore, it also has wider implications on the evolution of terpene synthases.
[Mh] Termos MeSH primário: Carbono-Oxigênio Liases/química
Liases Intramoleculares/química
[Mh] Termos MeSH secundário: Carbono-Oxigênio Liases/genética
Domínio Catalítico
Cicloexenos/química
Liases Intramoleculares/genética
Mentha spicata/enzimologia
Mentha spicata/genética
Modelos Moleculares
Mutagênese
Mutação
Fosfatos de Poli-Isoprenil/química
Terpenos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyclohexenes); 0 (Polyisoprenyl Phosphates); 0 (Terpenes); 763-10-0 (geranyl pyrophosphate); 9MC3I34447 (limonene); EC 4.2.- (Carbon-Oxygen Lyases); EC 4.2.3.119 ((-)-alpha-pinene synthase); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (pinene cyclase I)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170407
[Lr] Data última revisão:
170407
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170221
[St] Status:MEDLINE


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[PMID]:28190677
[Au] Autor:Despinasse Y; Fiorucci S; Antonczak S; Moja S; Bony A; Nicolè F; Baudino S; Magnard JL; Jullien F
[Ad] Endereço:Université de Lyon, F-42023, Saint-Etienne, France; Université de Saint-Etienne, Jean Monnet, F-42000, Saint-Etienne, France; Laboratoire de Biotechnologies Végétales Appliquées aux Plantes Aromatiques et Médicinales, EA 3061, 23 Rue du Dr Michelon, F-42000, Saint-Etienne, France.
[Ti] Título:Bornyl-diphosphate synthase from Lavandula angustifolia: A major monoterpene synthase involved in essential oil quality.
[So] Source:Phytochemistry;137:24-33, 2017 May.
[Is] ISSN:1873-3700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Lavender essential oils (EOs) of higher quality are produced by a few Lavandula angustifolia cultivars and mainly used in the perfume industry. Undesirable compounds such as camphor and borneol are also synthesized by lavender leading to a depreciated EO. Here, we report the cloning of bornyl diphosphate synthase of lavender (LaBPPS), an enzyme that catalyzes the production of bornyl diphosphate (BPP) and then by-products such as borneol or camphor, from an EST library. Compared to the BPPS of Salvia officinalis, the functional characterization of LaBPPS showed several differences in amino acid sequence, and the distribution of catalyzed products. Molecular modeling of the enzyme's active site suggests that the carbocation intermediates are more stable in LaBPPS than in SoBPPS leading probably to a lower efficiency of LaBPPS to convert GPP into BPP. Quantitative RT-PCR performed from leaves and flowers at different development stages of L. angustifolia samples show a clear correlation between transcript level of LaBPPS and accumulation of borneol/camphor, suggesting that LaBPPS is mainly responsible of in vivo biosynthesis of borneol/camphor in fine lavender. A phylogenetic analysis of terpene synthases (TPS) pointed out the basal position of LaBPPS in the TPSb clade, suggesting that LaBPPS could be an ancestor of others lavender TPSb. Finally, borneol could be one of the first monoterpenes to be synthesized in the Lavandula subgenus. Knowledge gained from these experiments will facilitate future studies to improve the lavender oils through metabolic engineering or plant breeding. Accession numbers: LaBPPS: KM015221.
[Mh] Termos MeSH primário: Liases Intramoleculares/metabolismo
Lavandula/enzimologia
Óleos Voláteis/química
Óleos Vegetais/química
Proteínas de Plantas/metabolismo
[Mh] Termos MeSH secundário: Alquil e Aril Transferases/genética
Alquil e Aril Transferases/metabolismo
Sequência de Aminoácidos
Bornanos/química
Cânfora/química
Domínio Catalítico
Clonagem Molecular
Flores/enzimologia
Liases Intramoleculares/genética
Modelos Moleculares
Filogenia
Folhas de Planta/enzimologia
Proteínas de Plantas/genética
Salvia officinalis/enzimologia
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bornanes); 0 (Oils, Volatile); 0 (Plant Oils); 0 (Plant Proteins); 76-22-2 (Camphor); EC 2.5.- (Alkyl and Aryl Transferases); EC 2.5.1.- (terpene synthase); EC 5.5.- (Intramolecular Lyases); EC 5.5.- (pinene cyclase I); EC 5.5.1.8 (geranyl-diphosphate cyclase); ZBP1YXW0H8 (lavender oil)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170407
[Lr] Data última revisão:
170407
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170214
[St] Status:MEDLINE



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