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1.
Sci Rep ; 5: 7700, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25572424

RESUMO

Fertilization is an indispensable step for formation of a zygote in sexual reproduction, leading to species survival. When mating occurs, sperm is transported to the female reproductive tracts via the seminal plasma (SP). SP is derived from male accessory sex glands and it plays pivotal roles for fertilization in animals. However, molecular mechanisms of SP or a fluid derived from male accessory sex glands for successful fertilization remain unclear. Here, we report that in male quail the cloacal gland (CG) produces prostaglandin F2α (PGF2α) that contributes to successful fertilization. PGF2α, as well as the secretion of CG (CGS), induced vaginal contractions and caused the opening of the entrance of the sperm storage tubules, the structures responsible for the long-term sperm storage and fertilization. The removal of CGS from the male before mating reduced the fertility, but the supplementation of CGS or PGF2α rescued the subfertility. We further showed that male CG contains glucose that is utilized as energy source for the intrinsic sperm mobility after transportation to female vagina. This mechanism, in concert with the excitatory effects of PGF2α enables successful fertilization in the domestic bird.


Assuntos
Fertilização , Animais , Animais Domésticos , Cromatografia Líquida de Alta Pressão , Cloaca/metabolismo , Dinoprosta/análise , Dinoprosta/farmacologia , Feminino , Masculino , Codorniz , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Vagina/efeitos dos fármacos , Vagina/fisiologia
2.
Z Naturforsch C J Biosci ; 65(9-10): 599-602, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21138062

RESUMO

Cell suspensions of Marchantia polymorpha hydrogenate progesterone to 5alpha-pregnane-3,20-dione. Structure elucidation of the product was achieved by comprehensive NMR analyses.


Assuntos
Marchantia/metabolismo , Progesterona/metabolismo , Monoterpenos Bicíclicos , Biotransformação , Células Cultivadas/metabolismo , Marchantia/citologia , Progesterona/química , Terpenos/química , Terpenos/metabolismo
3.
Bioorg Med Chem ; 17(1): 25-8, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19054677

RESUMO

On the basis of monitoring the prevention of accumulation of lipid droplets in mouse 3T3-L1 preadipocyte cells and inhibition of the proliferation of human colon cancer HT-29 cells, effective anti-corpulence and anticancer compounds were isolated from the peel of Citrus fruits. These bioactive components were identified as polymethoxyflavones and coumarin derivatives by spectroscopic analyses. 5-Hydroxy-6,7,8,3',4'-pentamethoxyflavone had the greatest anti-corpulence effects and 3,5,6,7,8,3',5'-heptamethoxyflavone had the greatest anticancer effects. Furthermore, distributions of those bioactive components in the peel of 10 species of Citrus fruits were demonstrated by HPLC analyses.


Assuntos
Fármacos Antiobesidade/isolamento & purificação , Antineoplásicos/isolamento & purificação , Citrus/química , Cumarínicos/isolamento & purificação , Flavonas/isolamento & purificação , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Animais , Fármacos Antiobesidade/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cumarínicos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Flavonas/farmacologia , Humanos , Camundongos
4.
Z Naturforsch C J Biosci ; 63(5-6): 403-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18669027

RESUMO

Stereospecific olefin (C=C) and carbonyl (C=O) reduction of the readily available prochiral compound ketoisophorone (2,2,6-trimethyl-2-cyclohexene-1,4-dione) (1) by Marchantia polymorpha and Nicotiana tabacum cell suspension cultures produce the chiral products (6R)-levodione (2), (4R,5S)-4-hydroxy-3,3,5-trimethylcyclohexanone (3), and (4R,6R)-actinol (4) as well as the minor components (4R)-hydroxyisophorone (5) and (4S)-phorenol (6).


Assuntos
Cicloexanonas/metabolismo , Marchantia/genética , Nicotiana/citologia , Polimorfismo Genético , Células Cultivadas , Cicloexanonas/química , Cinética , Espectroscopia de Ressonância Magnética , Marchantia/metabolismo , Análise Espectral , Estereoisomerismo , Nicotiana/metabolismo
5.
Biosci Biotechnol Biochem ; 72(7): 1764-71, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18603800

RESUMO

(-)-10-epi-Axisonitrile-3, a spirocyclic sesquiterpene isocyanide obtained from the marine sponge Geodia exigua, immobilized sperm of sea urchin and starfish to block fertilization at the minimum effective concentration of 0.4 microg/ml. On the other hand, fertilized eggs developed normally to the gastrula stage in the presence of a 250-times higher concentration of the isocyanide. Analysis by (31)P NMR revealed an accumulation of phosphocreatine and a depletion of inorganic phosphate in the isocyanide-treated sperm, suggesting that (-)-10-epi-axisonitrile-3 inhibited the phosphocreatine shuttle participating in the high-energy phosphate metabolism, thereby immobilizing sperm to block fertilization. No analogs of (-)-10-epi-axisonitrile-3 containing different functionalities or isocyanides with different carbon skeleton exhibited such activity.


Assuntos
Cianetos/farmacologia , Fertilização/efeitos dos fármacos , Nitrilas/farmacologia , Espermatozoides/efeitos dos fármacos , Compostos de Espiro/farmacologia , Animais , Cianetos/síntese química , Equinodermos , Embrião não Mamífero/efeitos dos fármacos , Células Germinativas/efeitos dos fármacos , Masculino , Fosfocreatina/antagonistas & inibidores , Poríferos , Sesquiterpenos , Relação Estrutura-Atividade , Zigoto/efeitos dos fármacos
6.
J Nat Prod ; 71(6): 1070-3, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18473477

RESUMO

Two new labdane diterpenes, 8alpha,19-dihydroxylabd-13 E-en-15-oic acid (1) and 13,14,15,16-tetranorlabdane-8alpha,12,14-triol (2), as well as an acetylated derivative, 8alpha-O-beta-D-glucopyranosyllabd-13 E-ene-15,19-diol-8alpha-2',3',4',6'-hexaacetate (3a), were isolated from the aerial parts of Crassocephalum mannii. The structures of 1, 2, and 3a were elucidated by spectroscopic data analysis. Selective inhibitory activity for 1 and 2 and their acetate derivatives, 1a and 2a, against cyclooxygenases (COX-1 and COX-2) was detected.


Assuntos
Asteraceae/química , Inibidores de Ciclo-Oxigenase/isolamento & purificação , Inibidores de Ciclo-Oxigenase/farmacologia , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Plantas Medicinais/química , Antineoplásicos Fitogênicos , Camarões , Inibidores de Ciclo-Oxigenase/química , Diterpenos/química , Isoenzimas , Estrutura Molecular
7.
Bioorg Chem ; 36(1): 23-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17945329

RESUMO

In the course of the purification of enone reductase participating to the reduction of pulegone, two reductases (NtRed-1 and NtRed-2) were isolated from cultured cells of Nicotiana tabacum. The partial amino acid sequences of the reductases revealed that NtRed-1 was allyl-alcohol dehydrogenase (Accession No. BAA89423) and NtRed-2 was malate dehydrogenase (Accession No. CAC12826). cDNA cloning and expression of these reductases in Escherichia coli were performed. Reduction with recombinant proteins was examined with cyclic alpha,beta-unsaturated ketones, such as pulegone, carvone and verbenone, as substrates. It was found that the recombinant NtRed-1 catalyses the hydrogenation of the exocyclic C-C double bond of pulegone.


Assuntos
DNA Complementar/genética , Escherichia coli/genética , Regulação Enzimológica da Expressão Gênica/genética , Cetonas/metabolismo , Nicotiana/enzimologia , Oxirredutases/genética , Oxirredutases/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , DNA Complementar/isolamento & purificação , Cetonas/química , Conformação Molecular , Dados de Sequência Molecular , Oxirredução , Oxirredutases/química , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência
8.
Nat Prod Res ; 21(8): 726-32, 2007 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-17616901

RESUMO

One novel and three known hydroxycinnamic acid derivatives having antioxidant activities were isolated from a Brazilian bee pollen. They were identified as kaempferol 3-O-[2-O-p-coumaroyl]-alpha-L-arabinopyranoside, N(1), N(5), N(10)-tri-p-coumaroyl spermidine, N(1), N(5), N(10), N(14)-tetra-p-coumaroyl spermine, and monocaffeoyl-tri-p-coumaroyl spermine, respectively. The structure of the kaempferol glycoside was established on the basis of spectroscopic and chemical investigations. Among the isolated compounds, monocaffeoyl-tri-p-coumaroyl spermine showed the strongest free radical-scavenging activity, which was almost identical to that of alpha-tocopherol. On the other hand, the antioxidant effect of tri-p-coumaroyl spermidine on autooxidation of linoleic acid was strongest and nearly equal to that of alpha-tocopherol.


Assuntos
Antioxidantes/isolamento & purificação , Ácidos Cumáricos/isolamento & purificação , Pólen/química , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Abelhas , Compostos de Bifenilo/metabolismo , Brasil , Dicroísmo Circular , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Hidrazinas/metabolismo , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Rotação Ocular , Picratos , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Phytochemistry ; 68(5): 680-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17258243

RESUMO

Fractionation of methylene chloride extracts of the resin of Ferula vesceritensis and F. sinaica afforded three sesquiterpene coumarins and a glucose derivative. One of them was a sesquiterpene with a rare carbon skeleton. The structures of these compounds were determined by extensive NMR studies, including DEPT, COSY, NOE, HMQC, and HMBC.


Assuntos
Cumarínicos/química , Ferula/química , Extratos Vegetais/química , Raízes de Plantas/química , Sesquiterpenos/química , Cumarínicos/isolamento & purificação , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Conformação Molecular , Extratos Vegetais/isolamento & purificação , Sesquiterpenos/isolamento & purificação
10.
J Nat Prod ; 69(3): 394-6, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16562842

RESUMO

A new diterpene glucoside (1), named sylviside, was isolated from the aerial parts of Gnaphalium sylvaticum. Its structure was elucidated as 2beta,15alpha,20alpha-trihydroxy-19,20-dicarboxy-ent-kaur-16-ene 2beta-O-(2'-angelate)-beta-D-glucopyranoside, on the basis of spectroscopic analysis ((1)H NMR, (13)C NMR, HMQC, HMBC, NOESY), and was confirmed by X-ray crystallographic analysis. Sylviside (1) displayed weak cytotoxicity against HeLa WT (human epitheloid cervical carcinoma) cells and was also evaluated for its effects on reversing multidrug resistance in HeLa cells overexpressing MDR1.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Diterpenos/isolamento & purificação , Glucosídeos/isolamento & purificação , Gnaphalium/química , Plantas Medicinais/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Diterpenos/química , Diterpenos/farmacologia , Resistência a Múltiplos Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Genes MDR/efeitos dos fármacos , Glucosídeos/química , Glucosídeos/farmacologia , Células HeLa , Humanos , Conformação Molecular , Estrutura Molecular , República de Belarus
11.
Z Naturforsch C J Biosci ; 60(3-4): 265-71, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15948594

RESUMO

Our previous study showed that approximately one-third of the nitrogen of 15N-labeled NO2 taken up into plants was converted to a previously unknown organic nitrogen (hereafter designated UN) that was not recoverable by the Kjeldahl method (Morikawa et al., 2004). In this communication, we discuss metabolic and physiological relevance of the UN based on our newest experimental results. All of the 12 plant species were found to form UN derived from NO2 (about 10-30% of the total nitrogen derived from NO2). The UN was formed also from nitrate nitrogen in various plant species. Thus, UN is a common metabolite in plants. The amount of UN derived from NO2 was greatly increased in the transgenic tobacco clone 271 (Vaucheret et al., 1992) where the activity of nitrite reductase is suppressed less than 5% of that of the wild-type plant. On the other hand, the amount of this UN was significantly decreased by the overexpression of S-nitrosoglutathione reductase (GSNOR). These findings strongly suggest that nitrite and other reactive nitrogen species are involved in the formation of the UN, and that the UN-bearing compounds are metabolizable. A metabolic scheme for the formation of UN-bearing compounds was proposed, in which nitric oxide and peroxynitrite derived from NO2 or endogenous nitrogen oxides are involved for nitrosation and/or nitration of organic compounds in the cells to form nitroso and nitro compounds, including N-nitroso and S-nitroso ones. Participation of non-symbiotic haemoglobin bearing peroxidase-like activity (Sakamoto et al., 2004) and GSNOR (Sakamoto et al., 2002) in the metabolism of the UN was discussed. The UN-bearing compounds identified to date in the extracts of the leaves of Arabidopsis thaliana fumigated with NO2 include a delta2-1,2,3-thiadiazoline derivative (Miyawaki et al., 2004) and 4-nitro-beta-carotene.


Assuntos
Nitrogênio/metabolismo , Plantas/metabolismo , Arabidopsis/metabolismo , Hordeum/metabolismo , Modelos Biológicos , Isótopos de Nitrogênio , Óxido Nitroso/metabolismo , Compostos Orgânicos/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Glycine max/metabolismo , Spinacia oleracea/metabolismo
12.
Z Naturforsch C J Biosci ; 60(3-4): 272-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15948595

RESUMO

Arabidopsis thaliana was transformed with a gene encoding a nitroreductase (NTR, E.C.1.6.99.7) with activity against a wide range of nitroaromatic compounds. The gene was transferred from Escherichia coli by an Agrobacterium-mediated in planta method. The obtained seeds were sowed to produce T1 plants, and they were assayed for the integration of the transgene in the plant genome. Transgenic plants that were positive with the PCR analysis were self-pollinated to produce T2 generation plants. Seven lines obtained were assayed for the NTR activity. While the non-transformed wild-type plants showed no detectable NTR activity, the enzyme activity of the transgenic plant lines was approx. 20 times higher. Using the line with the highest NTR activity, the phytoremediation characteristics of plants against 2,4,6-trinitrotoluene (TNT) was investigated. While the wild-type plants did not grow in the presence of 0.1 mM TNT, the transgenic plants grew almost normally in this condition. The uptake of TNT by seedlings of transgenic plants increased by 7 to 8 times when theywere floated on TNT solution. HPLC analysis showed that the peak due to TNT taken upinto plant body was much smaller in the transgenic plants as compared with that of the wild type, and that a number of peaks attributable to the degradation products of TNT, including 4-amino-2,6-dinitrotoluene, were detected in the extract from the transgenic plants. This indicates that the expression of bacterial NTR improved the capability of plants to degrade TNT.


Assuntos
Arabidopsis/metabolismo , Proteínas de Escherichia coli/metabolismo , Nitrorredutases/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Trinitrotolueno/farmacocinética , Sequência de Bases , Biodegradação Ambiental , Primers do DNA , Resistencia a Medicamentos Antineoplásicos/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Flavoproteínas/genética , Flavoproteínas/metabolismo , Cinética , Nitrorredutases/genética , Plasmídeos , Reação em Cadeia da Polimerase
13.
J Neurosurg ; 102(1): 161-6, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15658109

RESUMO

Occlusion of the parent artery is a traditional method of treatment of unclippable cerebral aneurysms. Surgical or endovascular occlusion of the parent artery proximal to the aneurysm has been recommended for the treatment of dissecting aneurysms located in the vertebrobasilar circulation. Nevertheless, occlusion of the parent artery may not result in permanent exclusion of the aneurysm from the systemic circulation because, occasionally, postoperative rebleeding occurs after proximal occlusion. Alternatively, endovascular occlusion of the affected site, including the aneurysmal dilation, and parent artery, is a safe and reliable treatment for dissecting aneurysms. The authors present two rare cases of ruptured vertebral artery (VA) dissecting aneurysms that were treated by endovascular occlusion of the affected site including the aneurysm and parent artery by using Guglielmi detachable coils. In both cases the VA recanalized in an antegrade fashion during the follow-up period. Based on these unique cases, the authors suggest that a careful angiographic follow up of dissecting aneurysms is required, even in patients successfully treated with endovascular occlusion of the affected artery and aneurysm.


Assuntos
Aneurisma Roto/complicações , Aneurisma Roto/terapia , Dissecção Aórtica/complicações , Dissecção Aórtica/terapia , Embolização Terapêutica/instrumentação , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/terapia , Artéria Vertebral , Dissecção Aórtica/diagnóstico , Angiografia Cerebral , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico , Masculino , Pessoa de Meia-Idade , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/patologia
14.
Planta ; 219(1): 14-22, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14963705

RESUMO

Plants take up inorganic nitrogen and store it unchanged or convert it to organic forms. The nitrogen in such organic compounds is stoichiometrically recoverable by the Kjeldahl method. The sum of inorganic nitrogen and Kjeldahl nitrogen has long been known to equal the total nitrogen in plants. However, in our attempt to study the mechanism of nitrogen dioxide (NO(2)) metabolism, we unexpectedly discovered that about one-third of the total nitrogen derived from (15)N-labeled NO(2) taken up by Arabidopsis thaliana (L.) Heynh. plants was converted to neither inorganic nor Kjeldahl nitrogen, but instead to an as yet unknown nitrogen compound(s). We here refer to this nitrogen as unidentified nitrogen ( UN). The generality of the formation of UN across species, nitrogen sources and cultivation environments for plants has been shown as follows. Firstly, all of the other 11 plant species studied were found to form the UN in response to fumigation with (15)NO(2). Secondly, tobacco ( Nicotiana tabacum L.) plants fed with (15)N-nitrate appeared to form the UN. And lastly, the leaves of naturally fed vegetables, grass and roadside trees were found to possess the UN. In addition, the UN appeared to comprise a substantial proportion of total nitrogen in these plant species. Collectively, all of our present findings imply that there is a novel nitrogen mechanism for the formation of UN in plants. Based on the analyses of the exhaust gas and residue fractions of the Kjeldahl digestion of a plant sample containing the UN, probable candidates for compounds that bear the UN were deduced to be those containing the heat-labile nitrogen-oxygen functions and those recalcitrant to Kjeldahl digestion, including organic nitro and nitroso compounds. We propose UN-bearing compounds may provide a chemical basis for the mechanism of the reactive nitrogen species (RNS), and thus that cross-talk may occur between UN and RNS metabolisms in plants. A mechanism for the formation of UN-bearing compounds, in which RNS are involved as intermediates, is proposed. The important broad impact of this novel nitrogen metabolism, not only on the general physiology of plants, but also on plant substances as human and animal food, and on plants as an integral part of the global environment, is discussed.


Assuntos
Dióxido de Nitrogênio/metabolismo , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Plantas/química , Plantas/metabolismo , Fumigação , Modelos Biológicos , Folhas de Planta/química
15.
Am J Med Sci ; 327(1): 38-43, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14722395

RESUMO

We report a 69-year-old woman with intracranial pachymeningitis showing hypopituitarism, diabetes insipidus, and Tolosa-Hunt syndrome associated with Hashimoto thyroiditis confirmed by autopsy. A large tumorous lesion of the hypothalamo-pituitary gland was revealed on magnetic resonance imaging, after the patient complained of gait and visual field disturbance. These symptoms subsided after thyroid hormone supplementation. Hypopituitarism and diabetes insipidus were diagnosed after cessation of the treatment by the patient herself. Multiple cranial nerve palsies and orbito-frontalgia appeared. Methylprednisolone pulse therapy improved the symptoms, but they recurred when the dose of glucocorticoid was decreased. The patient died of brain thrombosis. Autopsy revealed typical findings of Hashimoto thyroiditis and intracranial pachymeningitis involving the cranial base and pituitary gland. The high titer of rheumatoid factor and Hashimoto thyroiditis in this patient suggest an immunological role in the pathogenesis of pachymeningitis.


Assuntos
Diabetes Insípido Neurogênico/etiologia , Hipopituitarismo/etiologia , Meningite/etiologia , Tireoidite Autoimune/complicações , Idoso , Evolução Fatal , Feminino , Humanos , Neoplasias Hipotalâmicas/etiologia , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias/etiologia , Tireoidite Autoimune/tratamento farmacológico , Tireoidite Autoimune/fisiopatologia , Tiroxina/uso terapêutico , Campos Visuais/efeitos dos fármacos , Campos Visuais/fisiologia
16.
J Biosci Bioeng ; 98(2): 67-70, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-16233668

RESUMO

A novel 55-kDa hydroxylase was isolated from cultured cells of Catharanthus roseus by a three-step procedure: anion exchange chromatography, affinity chromatography and hydroxylapatite adsorption chromatography. The enzyme specifically catalyzed the hydroxylation of 2-hydroxybenzoic acid to give 2,5-dihydroxybenzoic acid. The enzyme activity was optimal at pH 7.8 and was completely inhibited by divalent cations, such as Cu(2+) and Hg(2+). The enzyme showed sequence similarity to certain plant flavonoid 3'-hydroxylases.

17.
Biochemistry ; 42(49): 14663-9, 2003 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-14661979

RESUMO

Cytochrome P450s in endoplasmic reticulum membranes function in the hydroxylation of exogenous and endogenous hydrophobic substrates concentrated in the membranes. The reactions require electron supplies from NADPH-cytochrome P450 reductase in the same membranes. The membranes play important roles in the reaction of cytochrome P450. The membrane topology of guinea pig P450 17alpha was investigated on the basis of the differences in reactivity to hydrophilic chemical modification reagents between those in the detergent-solubilized state and proteoliposomes. Recombinant guinea pig cytochrome P450 17alpha was purified from Escherichia coli and incorporated into liposome membranes. Lysine residues in the detergent-solubilized P450 17alpha and in the proteoliposomes were acetylated with acetic anhydride at pH 9.0, and the acidic amino acid residues were conjugated with glycinamide at pH 5.0 by the aid of a coupling reagent, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride. The modifications were performed under conditions where the denatured form, P420, was not induced. The modified P450 17alpha's were digested by trypsin, and the molecular weights of the peptide fragments were determined by MALDI-TOF mass spectrometry. From the increase in the molecular weights of the peptides, the positions of modifications could be deduced. In the detergent-solubilized state, 11 lysine residues and 7 acidic amino acid residues were modified, among which lysine residues at positions 29, 59, 490, and 492 and acidic residues at 211, 212, and/or 216 were not modified in the proteoliposomes. Both the N- and C-terminal domains and the putative F-G loop were concluded to be in or near the membrane-binding domains of P450 17alpha.


Assuntos
Membranas Intracelulares/química , Proteínas de Membrana/química , Esteroide 17-alfa-Hidroxilase/química , Acetilação , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Detergentes , Glicina/metabolismo , Cobaias , Membranas Intracelulares/metabolismo , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , Proteolipídeos/química , Proteolipídeos/metabolismo , Análise de Sequência de Proteína , Solubilidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria , Esteroide 17-alfa-Hidroxilase/isolamento & purificação , Esteroide 17-alfa-Hidroxilase/metabolismo , Tripsina
18.
Biol Pharm Bull ; 26(12): 1725-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14646179

RESUMO

In the present study, essential oil from the leaves of Syrian oreganum [Origanum syriacum L. (Lauraceae)] grown in Turkish state forests of the Dortyol district, Turkey, was obtained by steam distillation. The chemical composition of oil was analysed by GC and GC-MS, and was found to contain 49.02% monoterpenes, 36.60% oxygenated monoterpenes and 12.59% sesquiterpenes. The major components are as follows: gamma-terpinene, carvacrol, p-cymene and beta-caryophyllene. Subsequently, the reducing power, antioxidant and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities of the essential oil were studied. The reducing power was compared with ascorbic acid, and the other activities were compared with 2,6-di-tert-butyl-4-methyl phenol (BHT, butylated hydroxytoluene). The results showed that the activities were concentration dependent. The antioxidant activities of the oil were slightly lower than those of ascorbic acid or BHT, so the oil can be considered an effective natural antioxidant. Antimicrobial activities of the essential oil from the leaves of Origanum syriacum was also determined on 16 microorganisms tested using the agar-disc diffusion method, and showed antimicrobial activity against 13 of these.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Óleos Voláteis/química , Origanum/química , Óleos de Plantas/química , Ampicilina/farmacologia , Ampicilina/normas , Anti-Infecciosos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Ácido Ascórbico/farmacologia , Ácido Ascórbico/normas , Compostos de Bifenilo , Monoterpenos Cicloexânicos , Cimenos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Sequestradores de Radicais Livres/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/crescimento & desenvolvimento , Micrococcus luteus/efeitos dos fármacos , Micrococcus luteus/crescimento & desenvolvimento , Monoterpenos/química , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Nistatina/farmacologia , Nistatina/normas , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Picratos/farmacologia , Picratos/normas , Folhas de Planta/química , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia , Plantas Medicinais , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Estreptomicina/farmacologia , Estreptomicina/normas , Turquia
19.
Bioorg Med Chem ; 11(8): 1715-21, 2003 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-12659758

RESUMO

The marine sponge Monotria japonica contains cytolytic constituents, which have been fractionated to a new alpha,beta,gamma,delta-unsaturated carboxylic acid designated monotriajaponide A (1) and three new cyclic peroxides designated monotriajaponides B (2), C (3), and D (4), in addition to a known peroxide (5) and a known alpha,beta-unsaturated ester (6). The structures were determined on the basis of spectroscopic data. Compounds 1-5 lysed immature starfish (Asterina pectinifera) oocytes without affecting nuclear morphology at the minimum effective concentrations of 50, 6.3, 6.3, 6.3, and 13 microg/mL, respectively. On the other hand, compound 6, at the minimum effective concentration of 25 microg/mL, lysed both oocyte's plasma membrane and the nuclear envelope.


Assuntos
Ácidos Carboxílicos/farmacologia , Núcleo Celular/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Peróxidos/farmacologia , Poríferos/química , Animais , Ácidos Carboxílicos/química , Ácidos Carboxílicos/isolamento & purificação , Núcleo Celular/ultraestrutura , Dioxanos/química , Microscopia de Fluorescência , Ressonância Magnética Nuclear Biomolecular , Oócitos/citologia , Oócitos/ultraestrutura , Peróxidos/química , Peróxidos/isolamento & purificação , Estrelas-do-Mar , Estereoisomerismo
20.
J Biosci Bioeng ; 96(6): 581-4, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-16233578

RESUMO

The biotransformation of limonene and limonene oxide by the cyanobacterium, Synechococcus sp. PCC 7942, was investigated. (S)-(+)-Limonene was hydroxylated stereo- and regioselectively at its allylic position of the endocyclic C=C double bond by the cyanobacterial cells to its corresponding alcohol. The cells also showed the ability for the enantio- and stereoselective cleavage of the epoxide group of (1S,2R,4R)-limonene oxide to give (1S,2S,4R)-limonene-1,2-diol. The repetitive production of carveol from limonene was achieved using Ca2+-alginate-immobilized cyanobacterial cells.

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