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  1 / 1953 MEDLINE  
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[PMID]:29328637
[Au] Autor:Filipovic M; Gledovic A; Lukic M; Tasic-Kostov M; Isailovic T; Pantelic I; Vuleta G; Savic S
[Ti] Título:Alp Rose stem cells, olive oil squalene and a natural alkyl polyglucoside emulsifier: Are they appropriate ingredients of skin moisturizers - in vivo efficacy on normal and sodium lauryl sulfate - irritated skin?.
[So] Source:Vojnosanit Pregl;73(11):991-1002, 2016 11.
[Is] ISSN:0042-8450
[Cp] País de publicação:Serbia
[La] Idioma:eng
[Ab] Resumo:Background/Aim: Since skin moisturization may be achieved by both actives and chosen carrier, plant stem cells, squalene and natural alkyl polyglucoside emulsifier may be potential components of contemporary cosmetic products. The aim of the study was in vivo evaluation of the skin irritation potential and the efficacy of Alpine Rose stem cells incorporated into li-posomes and olive oil squalene as ingredients of moisturizing creams, with respect to the novel emulsifier used for creams' stabilization. Methods: With the employment of noninvasive skin biophysical measurements, skin hydration (EC), transepi-dermal water loss (TEWL), erythema index (EI) and viscoelas-ticity were measured on 76 healthy volunteers. In the first phase, skin irritation after a 24-hour occlusion and the long-term efficacy of creams (a 21-day study) on healthy skin were evaluated. Phase II of the study focused on the cream efficacy assessment after a 6-day treatment of sodium lauryl sulfate-irritated skin. Results: After a 24-hour occlusion, there were no significant changes in the EI for any tested sample. In the second phase of the study, the EI was not significantly altered for the cream containing squalene, while the application of all active samples resulted in a significant reduction of TEWL. In both phases of the study an EC increase was recorded, espe-cially for the squalene-containing cream. Conclusion: Due to the lack of skin irritation and skin barrier impairment along with the marked hydration effect, it could be said that the in-vestigated actives incorporated into alkyl polyglucoside emulsi-fier-stabilized creams may be safely applied as ingredients for "tailor-made" cosmetic moisturizers intended for normal and dry skin care, whereas olive oil squalene could be used for the treatment of irritated or sensitive skin as well. [Projekat Ministarstva nauke Republike Srbije, br. TR34031]
[Mh] Termos MeSH primário: Emulsificantes/administração & dosagem
Glucosídeos/administração & dosagem
Azeite de Oliva/química
Rhododendron/citologia
Creme para a Pele/administração & dosagem
Testes de Irritação da Pele/métodos
Pele/efeitos dos fármacos
Dodecilsulfato de Sódio/toxicidade
Esqualeno/administração & dosagem
Células-Tronco/fisiologia
[Mh] Termos MeSH secundário: Administração Cutânea
Adulto
Segurança de Produtos ao Consumidor
Método Duplo-Cego
Elasticidade
Emulsificantes/efeitos adversos
Feminino
Glucosídeos/efeitos adversos
Seres Humanos
Lipossomos
Fitoterapia
Plantas Medicinais
Medição de Risco
Sérvia
Pele/metabolismo
Pele/patologia
Creme para a Pele/efeitos adversos
Esqualeno/efeitos adversos
Esqualeno/isolamento & purificação
Fatores de Tempo
Viscosidade
Perda Insensível de Água/efeitos dos fármacos
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL
[Nm] Nome de substância:
0 (Emulsifying Agents); 0 (Glucosides); 0 (Liposomes); 0 (Olive Oil); 368GB5141J (Sodium Dodecyl Sulfate); 7QWM220FJH (Squalene)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180113
[St] Status:MEDLINE
[do] DOI:10.2298/VSP150116122F


  2 / 1953 MEDLINE  
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[PMID]:28881085
[Au] Autor:Tenkovskaia L; Murakami M; Okuno K; Ueda D; Sato T
[Ad] Endereço:Department of Applied Biological Chemistry, Faculty of Agriculture, and, Graduate School of Science and Technology, Niigata University, Ikarashi 2-8050, Nishi-ku, Niigata, 950-2181, Japan.
[Ti] Título:Analysis of the Catalytic Mechanism of Bifunctional Triterpene/Sesquarterpene Cyclase: Tyr167 Functions To Terminate Cyclization of Squalene at the Bicyclic Step.
[So] Source:Chembiochem;18(19):1910-1913, 2017 Oct 05.
[Is] ISSN:1439-7633
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Onoceroids are a group of triterpenes biosynthesized from squalene or dioxidosqualene by cyclization from both termini. We previously identified a bifunctional triterpene/sesquarterpene cyclase (TC) that constructs a tetracyclic scaffold from tetraprenyl-ß-curcumene (C ) but a bicyclic scaffold from squalene (C ) in the first reaction. TC also accepts the bicyclic intermediate as a substrate and generates tetracyclic and pentacyclic onoceroids in the second reaction. In this study, we analyzed the catalytic mechanism of an onoceroid synthase by using mutated enzymes. TC produced an unnatural tricyclic triterpenol, but TC , TC , and TC formed small quantities of tricyclic compounds, which suggested that the bulk size at Y167 contributed to termination of the cyclization of squalene at the bicyclic step. Our findings provide insight into the unique catalytic mechanism of TC, which triggers different cyclization modes depending on the substrate. These findings may facilitate the large-scale production of an onoceroid for which natural sources are limited.
[Mh] Termos MeSH primário: Biocatálise
Transferases Intramoleculares/metabolismo
Esqualeno/metabolismo
Tirosina/metabolismo
[Mh] Termos MeSH secundário: Bacillus/enzimologia
Ciclização
Estrutura Molecular
Esqualeno/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
42HK56048U (Tyrosine); 7QWM220FJH (Squalene); EC 5.4.- (Intramolecular Transferases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170908
[St] Status:MEDLINE
[do] DOI:10.1002/cbic.201700329


  3 / 1953 MEDLINE  
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[PMID]:28845666
[Au] Autor:Paramasivan K; Mutturi S
[Ad] Endereço:Microbiology and Fermentation Technology Department, CSIR-Central Food Technological Research Institute , Mysore, India.
[Ti] Título:Regeneration of NADPH Coupled with HMG-CoA Reductase Activity Increases Squalene Synthesis in Saccharomyces cerevisiae.
[So] Source:J Agric Food Chem;65(37):8162-8170, 2017 Sep 20.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Although overexpression of the tHMG1 gene is a well-known strategy for terpene synthesis in Saccharomyces cerevisiae, the optimal level for tHMG1p has not been established. In the present study, it was observed that two copies of the tHMG1 gene on a dual gene expression cassette improved squalene synthesis in laboratory strain by 16.8-fold in comparison to single-copy expression. It was also observed that tHMG1p is limited by its cofactor (NADPH), as the overexpression of NADPH regenerating genes', viz., ZWF1 and POS5 (full length and without mitochondrial presequence), has led to its increased enzyme activity. Further, it was demonstrated that overexpression of full-length POS5 has improved squalene synthesis in cytosol. Finally, when tHMG1 and full-length POS5 were co-overexpressed there was a net 27.5-fold increase in squalene when compared to control strain. These results suggest novel strategies to increase squalene accumulation in S. cerevisiae.
[Mh] Termos MeSH primário: Acil Coenzima A/metabolismo
Hidroximetilglutaril-CoA Redutases/metabolismo
NADP/metabolismo
Proteínas de Saccharomyces cerevisiae/metabolismo
Saccharomyces cerevisiae/metabolismo
Esqualeno/metabolismo
[Mh] Termos MeSH secundário: Acil Coenzima A/genética
Hidroximetilglutaril-CoA Redutases/genética
Proteínas Mitocondriais/genética
Proteínas Mitocondriais/metabolismo
Fosfotransferases (Aceptor do Grupo Álcool)/genética
Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo
Saccharomyces cerevisiae/enzimologia
Saccharomyces cerevisiae/genética
Proteínas de Saccharomyces cerevisiae/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acyl Coenzyme A); 0 (Mitochondrial Proteins); 0 (Saccharomyces cerevisiae Proteins); 1553-55-5 (3-hydroxy-3-methylglutaryl-coenzyme A); 53-59-8 (NADP); 7QWM220FJH (Squalene); EC 1.1.1.- (Hydroxymethylglutaryl CoA Reductases); EC 2.7.1.- (Phosphotransferases (Alcohol Group Acceptor)); EC 2.7.1.86 (POS5 protein, S cerevisiae)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170829
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b02945


  4 / 1953 MEDLINE  
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[PMID]:28813599
[Au] Autor:Thapa HR; Tang S; Sacchettini JC; Devarenne TP
[Ad] Endereço:Department of Biochemistry & Biophysics, Texas A&M University , College Station, Texas 77843, United States.
[Ti] Título:Tetraterpene Synthase Substrate and Product Specificity in the Green Microalga Botryococcus braunii Race L.
[So] Source:ACS Chem Biol;12(9):2408-2416, 2017 Sep 15.
[Is] ISSN:1554-8937
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Recently, the biosynthetic pathway for lycopadiene, a C tetraterpenoid hydrocarbon, was deciphered from the L race of Botryococcus braunii, an alga that produces hydrocarbon oils capable of being converted into combustible fuels. The lycopadiene pathway is initiated by the squalene synthase (SS)-like enzyme lycopaoctaene synthase (LOS), which catalyzes the head-to-head condensation of two C geranylgeranyl diphosphate (GGPP) molecules to produce C lycopaoctaene. LOS shows unusual substrate promiscuity for SS or SS-like enzymes by utilizing C farnesyl diphosphate (FPP) and C phytyl diphosphate in addition to GGPP as substrates. These three substrates can be combined by LOS individually or in combinations to produce six different hydrocarbons of C , C , and C chain lengths. To understand LOS substrate and product specificity, rational mutagenesis experiments were conducted based on sequence alignment with several SS proteins as well as a structural comparison with the human SS (HSS) crystal structure. Characterization of the LOS mutants in vitro identified Ser276 and Ala288 in the LOS active site as key amino acids responsible for controlling substrate binding, and thus the promiscuity of this enzyme. Mutating these residues to those found in HSS largely converted LOS from lycopaoctaene production to C squalene production. Furthermore, these studies were confirmed in vivo by expressing LOS in E. coli cells metabolically engineered to produce high FPP and GGPP levels. These studies also offer insights into tetraterpene hydrocarbon metabolism in B. braunii and provide a foundation for engineering LOS for robust production of specific hydrocarbons of a desired chain length.
[Mh] Termos MeSH primário: Clorófitas/enzimologia
Farnesil-Difosfato Farnesiltransferase/metabolismo
Microalgas/enzimologia
Fosfatos de Poli-Isoprenil/metabolismo
Esqualeno/metabolismo
Terpenos/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Vias Biossintéticas
Clorófitas/química
Clorófitas/metabolismo
Farnesil-Difosfato Farnesiltransferase/química
Seres Humanos
Microalgas/química
Microalgas/metabolismo
Modelos Moleculares
Alinhamento de Sequência
Sesquiterpenos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Polyisoprenyl Phosphates); 0 (Sesquiterpenes); 0 (Terpenes); 79W6B01D07 (farnesyl pyrophosphate); 7QWM220FJH (Squalene); EC 2.5.1.21 (Farnesyl-Diphosphate Farnesyltransferase); N21T0D88LX (geranylgeranyl pyrophosphate)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170817
[St] Status:MEDLINE
[do] DOI:10.1021/acschembio.7b00457


  5 / 1953 MEDLINE  
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[PMID]:28795620
[Au] Autor:Otagiri M; Khalid A; Moriya S; Osada H; Takahashi S
[Ad] Endereço:a Biomass Research Platform Team , RIKEN Centre for Sustainable Resource Science , Yokohama , Japan.
[Ti] Título:Novel squalene-producing thraustochytrids found in mangrove water.
[So] Source:Biosci Biotechnol Biochem;81(10):2034-2037, 2017 Oct.
[Is] ISSN:1347-6947
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:On extended screening of squalene-producing strains in Okinawa mangrove water, we identified 14 novel squalene-producing thraustochytrids from 172 unialgal clonal isolates. The novel thraustochytrids produced 13.9-7.54 mg squalene/g dry cell weight. Eight isolates were found to belong to potentially novel squalene-producing genera, forming a monophyletic cluster independent from any known thraustochytrids.
[Mh] Termos MeSH primário: Esqualeno/metabolismo
Estramenópilas/metabolismo
Microbiologia da Água
Zonas Úmidas
[Mh] Termos MeSH secundário: RNA Ribossômico 18S/genética
Estramenópilas/genética
Estramenópilas/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 18S); 7QWM220FJH (Squalene)
[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:170811
[St] Status:MEDLINE
[do] DOI:10.1080/09168451.2017.1359485


  6 / 1953 MEDLINE  
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[PMID]:28750236
[Au] Autor:Santivañez-Veliz M; Moreno-Viguri E; Pérez-Silanes S; Varela J; Cerecetto H; González M; Lizarraga E
[Ad] Endereço:Universidad de Navarra, Instituto de Salud Tropical, Campus Universitario, 31080, Pamplona, Spain; Universidad de Navarra, Departamento de Química orgánica y Farmacéutica, Facultad de Farmacia y Nutrición, Campus Universitario, 31080, Pamplona, Spain.
[Ti] Título:Development, validation and application of a GC-MS method for the simultaneous detection and quantification of neutral lipid species in Trypanosoma cruzi.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1061-1062:225-232, 2017 Sep 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The development and validation of an analytical method for the simultaneous analysis of five neutral lipids in Trypanosoma cruzi epimastigotes by GC-MS is presented in this study. The validated method meets all validation parameters for all components and the chromatographic conditions have been optimized during its development. This analytical method has demonstrated good selectivity, accuracy, within-day precision, recovery and linearity in each of the established ranges. In addition, detection and quantification limits for squalene, cholesterol, ergosterol and lanosterol have been improved and it is worth highlighting the fact that this is the first time that squalene-2,3-epoxide validation data have been reported. The new validated method has been applied to epimastigotes treated with compounds with in vitro anti-T.cruzi activity. This new methodology is straightforward and constitutes a tool for screening possible sterol biosynthesis pathway inhibitors in Trypanosoma cruzi, one of the most studied targets in Chagas disease treatment. Therefore, it is an interesting and useful contribution to medicinal chemistry research.
[Mh] Termos MeSH primário: Cromatografia Gasosa-Espectrometria de Massas/métodos
Esqualeno/análise
Esteróis/análise
Trypanosoma cruzi/química
[Mh] Termos MeSH secundário: Animais
Limite de Detecção
Modelos Lineares
Reprodutibilidade dos Testes
Esqualeno/análogos & derivados
Trypanosoma cruzi/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Sterols); 7QWM220FJH (Squalene)
[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:170728
[St] Status:MEDLINE


  7 / 1953 MEDLINE  
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[PMID]:28416486
[Au] Autor:Kotelevets L; Chastre E; Caron J; Mougin J; Bastian G; Pineau A; Walker F; Lehy T; Desmaële D; Couvreur P
[Ad] Endereço:Institut Galien Paris-Sud, UMR 8612, CNRS; Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France.
[Ti] Título:A Squalene-Based Nanomedicine for Oral Treatment of Colon Cancer.
[So] Source:Cancer Res;77(11):2964-2975, 2017 Jun 01.
[Is] ISSN:1538-7445
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nanotechnology offers many possibilities to improve drug treatments, including with regard to drug pharmacology. The current study reports a simple approach to improve cisplatin efficacy in the treatment of colon cancer through the creation of orally administered squalenoylated nanoparticles loaded with cisplatin (SQ-CDDP NP). Cytotoxic effects of SQ-CDDP NP were assessed in human colonic cells and in mouse models of intestinal cancer. In cell culture, SQ-CDDP NP exhibited at least 10-fold greater cytotoxic potency compared with uncomplexed cisplatin, reflecting an enhancement in intracellular accumulation and DNA platination. Mechanistic investigations showed that SQ-CDDP NP stimulated ROS production, expression of heavy metal-inducible and stress-inducible genes, stress kinase cascades, and apoptosis. In Apc mice, a model of intestinal tumorigenesis, oral administration of SQ-CDDP NP curtailed spontaneous tumor formation and azoxymethane-induced colon carcinogenesis with no apparent evidence of tissue toxicity. Our results offer preclinical validation of a nanocarrier formulation that can safely improve chemotherapeutic efficacy, address risks of drug resistance, and improve patient compliance by enabling oral administration. .
[Mh] Termos MeSH primário: Antineoplásicos/uso terapêutico
Neoplasias do Colo/tratamento farmacológico
Nanomedicina/métodos
Esqualeno/uso terapêutico
[Mh] Termos MeSH secundário: Administração Oral
Animais
Antineoplásicos/farmacologia
Apoptose
Proliferação Celular
Neoplasias do Colo/patologia
Modelos Animais de Doenças
Seres Humanos
Camundongos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antineoplastic Agents); 7QWM220FJH (Squalene)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170419
[St] Status:MEDLINE
[do] DOI:10.1158/0008-5472.CAN-16-1741


  8 / 1953 MEDLINE  
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[PMID]:28375554
[Au] Autor:McDonald JU; Zhong Z; Groves HT; Tregoning JS
[Ad] Endereço:Mucosal Infection and Immunity group, Section of Virology, Department of Medicine, Imperial College London, London, UK.
[Ti] Título:Inflammatory responses to influenza vaccination at the extremes of age.
[So] Source:Immunology;151(4):451-463, 2017 Aug.
[Is] ISSN:1365-2567
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Age affects the immune response to vaccination, with individuals at the extremes of age responding poorly. The initial inflammatory response to antigenic materials shapes the subsequent adaptive response and so understanding is required about the effect of age on the profile of acute inflammatory mediators. In this study we measured the local and systemic inflammatory response after influenza vaccination or infection in neonatal, young adult and aged mice. Mice were immunized intramuscularly with inactivated influenza vaccine with and without the adjuvant MF59 and then challenged with H1N1 influenza. Age was the major factor affecting the inflammatory profile after vaccination: neonatal mice had more interleukin-1α (IL-1α), C-reactive protein (CRP) and granulocyte-macrophage colony-stimulating factor (GMCSF), young adults more tumour necrosis factor-α (TNF), and elderly mice more interleukin-1 receptor antagonist (IL-1RA), IL-2RA and interferon-γ-induced protein 10 (IP10). Notably the addition of MF59 induced IL-5, granulocyte colony-stimulating factor (G-CSF), Keratinocyte Chemotractant (KC) and monocyte chemoattractant protein 1 (MCP1) in all ages of animals and levels of these cytokines correlated with antibody responses. Age also had an impact on the efficacy of vaccination: neonatal and young adult mice were protected against challenge, but aged mice were not. There were striking differences in the localization of the cytokine response depending on the route of exposure: vaccination led to a high serum response whereas intranasal infection led to a low serum response but a high lung response. In conclusion, we demonstrate that age affects the inflammatory response to both influenza vaccination and infection. These age-induced differences need to be considered when developing vaccination strategies for different age groups.
[Mh] Termos MeSH primário: Envelhecimento/imunologia
Vírus da Influenza A Subtipo H1N1/imunologia
Vacinas contra Influenza/imunologia
Influenza Humana/imunologia
Pulmão/imunologia
Infecções por Orthomyxoviridae/imunologia
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Anticorpos Antivirais/sangue
Citocinas/metabolismo
Seres Humanos
Mediadores da Inflamação/metabolismo
Pulmão/virologia
Camundongos
Polissorbatos/administração & dosagem
Esqualeno/administração & dosagem
Vacinação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Viral); 0 (Cytokines); 0 (Inflammation Mediators); 0 (Influenza Vaccines); 0 (MF59 oil emulsion); 0 (Polysorbates); 7QWM220FJH (Squalene)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170915
[Lr] Data última revisão:
170915
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170405
[St] Status:MEDLINE
[do] DOI:10.1111/imm.12742


  9 / 1953 MEDLINE  
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[PMID]:28340291
[Au] Autor:Schwalen CJ; Feng X; Liu W; O-Dowd B; Ko TP; Shin CJ; Guo RT; Mitchell DA; Oldfield E
[Ad] Endereço:Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, IL, 61801, USA.
[Ti] Título:Head-to-Head Prenyl Synthases in Pathogenic Bacteria.
[So] Source:Chembiochem;18(11):985-991, 2017 Jun 01.
[Is] ISSN:1439-7633
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Many organisms contain head-to-head isoprenoid synthases; we investigated three such types of enzymes from the pathogens Neisseria meningitidis, Neisseria gonorrhoeae, and Enterococcus hirae. The E. hirae enzyme was found to produce dehydrosqualene, and we solved an inhibitor-bound structure that revealed a fold similar to that of CrtM from Staphylococcus aureus. In contrast, the homologous proteins from Neisseria spp. carried out only the first half of the reaction, yielding presqualene diphosphate (PSPP). Based on product analyses, bioinformatics, and mutagenesis, we concluded that the Neisseria proteins were HpnDs (PSPP synthases). The differences in chemical reactivity to CrtM were due, at least in part, to the presence of a PSPP-stabilizing arginine in the HpnDs, decreasing the rate of dehydrosqualene biosynthesis. These results show that not only S. aureus but also other bacterial pathogens contain head-to-head prenyl synthases, although their biological functions remain to be elucidated.
[Mh] Termos MeSH primário: Bactérias/enzimologia
Neopreno/metabolismo
Terpenos/metabolismo
[Mh] Termos MeSH secundário: Enterococcus hirae/enzimologia
Neisseria gonorrhoeae/enzimologia
Neisseria meningitidis/enzimologia
Fosfatos de Poli-Isoprenil/metabolismo
Prenilação
Esqualeno/análogos & derivados
Esqualeno/metabolismo
Staphylococcus aureus/enzimologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Polyisoprenyl Phosphates); 0 (Terpenes); 0 (prenyl); 11051-27-7 (dehydrosqualene); 29849-75-0 (presqualene pyrophosphate); 7QWM220FJH (Squalene); 9010-98-4 (Neoprene)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170826
[Lr] Data última revisão:
170826
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170325
[St] Status:MEDLINE
[do] DOI:10.1002/cbic.201700099


  10 / 1953 MEDLINE  
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[PMID]:28333447
[Au] Autor:Tatli M; Naik MT; Okada S; Dangott LJ; Devarenne TP
[Ti] Título:Isolation and Characterization of Cyclic C Botryococcenes and a Trimethylsqualene Isomer from Botryococcus braunii Race B.
[So] Source:J Nat Prod;80(4):953-958, 2017 Apr 28.
[Is] ISSN:1520-6025
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Three cyclic C botryococcenes and one new trimethylsqualene isomer were isolated from the B race, Showa (Berkeley) strain of Botryococcus braunii, which is known to produce large amounts of isoprenoid hydrocarbons ranging in carbon number from 30 to 34. Their purity was determined by GC-MS, and structures were characterized by 1D and 2D NMR. One of these molecules, cyclic C -1 botryococcene (5), has an unusual connection of a methylenecyclohexane ring to the molecule backbone not seen before in botryococcenes. This report further adds to our knowledge of the wide range of isoprenoid hydrocarbon structures produced by B. braunii.
[Mh] Termos MeSH primário: Clorófitas/química
Esqualeno/análogos & derivados
Terpenos/isolamento & purificação
[Mh] Termos MeSH secundário: Cromatografia Gasosa-Espectrometria de Massas
Isomerismo
Estrutura Molecular
Ressonância Magnética Nuclear Biomolecular
Esqualeno/química
Esqualeno/isolamento & purificação
Terpenos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Terpenes); 0 (trimethylsqualene); 7QWM220FJH (Squalene)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170801
[Lr] Data última revisão:
170801
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170324
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jnatprod.6b00934



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