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1.
Biomed Res Int ; 2019: 1341370, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016184

RESUMO

A novel lectin (ABL) was purified from the dried fruiting bodies of Agaricus bitorquis. An efficient 3-step purification protocol involved two consecutive steps of ion exchange chromatography on Q-Sepharose and SP-Sepharose and gel filtration by FPLC on Superdex 75. ABL is a monomeric protein with the molecular mass of 27.6 kDa, which is different from other lectins from genus Agaricus. Its N-terminal amino acid sequence is EYTISIRVYQTNPKGFNRPV which is unique and sharing considerably high similarity of other mushroom lectins. The hemagglutinating activity of the lectin was inhibited by inulin. Based on hemagglutination tests, ABL prefers rabbit, human type A, and AB erythrocytes to human type B and O erythrocytes. The lectin inhibits the activity of HIV-1 reverse transcriptase and the proliferation of leukemia cell (L1210) with an IC50 value of 4.69 and 4.97 µM, respectively. Furthermore, ABL demonstrates the highest mitogenic activity with a response of 24177.7 ± 940.6 [3H-methyl] thymidine counts per minute (CPM) at a concentration of 0.91 µM.


Assuntos
Agaricales/química , Agaricus/química , Proliferação de Células/efeitos dos fármacos , Transcriptase Reversa do HIV/antagonistas & inibidores , Inulina/metabolismo , Lectinas/farmacologia , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemaglutinação/efeitos dos fármacos , Testes de Hemaglutinação/métodos , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Coelhos
2.
World J Clin Cases ; 6(16): 1210-1216, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30613685

RESUMO

BACKGROUND: Chondromyxoid fibroma (CMF) is a rare benign bone tumour of cartilaginous origin, which usually affects the metaphysis of the long bone. Involvement of the temporal bone is extremely rare. Patients with CMF in the temporal bone can present some neurological deficits due to involvement of surrounding neural structures. CASE SUMMARY: We present the first case of histopathologically proven CMF originating in the temporal bone and involving the hypoglossal canal in a 40-year-old woman. Hypoglossal nerve paralysis was identified on the cranial nerve examination. The patient underwent surgical excision and was neurologically normal except for mild left facial palsy on 5-mo follow-up examination after surgery. In the current report, the major characteristics and computed tomography/magnetic resonance imaging features of the lesion are discussed. Furthermore, previous literature regarding this pathology is reviewed. CONCLUSION: The current study presents the first case of temporal bone CMF involving the hypoglossal canal.

3.
Clin Radiol ; 71(7): 691-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27180083

RESUMO

AIM: To evaluate whether some magnetic resonance imaging (MRI) signs suggesting idiopathic intracranial hypertension (IIH) could also be found in intracranial hypertension (IH) due to cerebral venous thrombosis (CVT) and to assess their possible contribution to diagnosing this disorder. MATERIALS AND METHODS: Thirty-one patients with IH due to CVT were evaluated prospectively using MRI. A group of 33 age- and sex-matched healthy volunteers served as controls. The optic nerve and sheath, pituitary gland, and ventricles were assessed. The prevalence of each imaging feature was compared between the two groups. RESULTS: Optic nerve sheath (ONS) dilatation and decreased pituitary gland height were the most valid signs suggesting IH in CVT patients: sensitivity 70.97% and 87.1%, respectively; specificity 96.97% and 72.73%, respectively; area under the curve 0.840 and 0.809, respectively. The MRI finding that showed the strongest association with IH in CVT patients was ONS dilatation (odds ratio 78.5). CONCLUSIONS: The combination of T1-weighted volumetric MRI and magnetic resonance venography could be helpful for diagnosing IH with CVT. Abnormalities of the ONS and the pituitary gland were reliable diagnostic signs for IH due to CVT.


Assuntos
Veias Cerebrais/patologia , Hipertensão Intracraniana/complicações , Hipertensão Intracraniana/patologia , Angiografia por Ressonância Magnética/métodos , Trombose dos Seios Intracranianos/complicações , Trombose dos Seios Intracranianos/patologia , Adulto , Veias Cerebrais/diagnóstico por imagem , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Trombose dos Seios Intracranianos/diagnóstico por imagem
4.
Biomed Res Int ; 2014: 417461, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25540778

RESUMO

A novel laccase was isolated and purified from fermentation mycelia of mushroom Coprinus comatus with an isolation procedure including three ion-exchange chromatography steps on DEAE-cellulose, CM-cellulose, and Q-Sepharose and one gel-filtration step by fast protein liquid chromatography on Superdex 75. The purified enzyme was a monomeric protein with a molecular weight of 64 kDa. It possessed a unique N-terminal amino acid sequence of AIGPVADLKV, which has considerably high sequence similarity with that of other fungal laccases, but is different from that of C. comatus laccases reported. The enzyme manifested an optimal pH value of 2.0 and an optimal temperature of 60°C using 2,2'-azinobis(3-ethylbenzothiazolone-6-sulfonic acid) diammonium salt (ABTS) as the substrate. The laccase displayed, at pH 2.0 and 37°C, K(m) values of 1.59 mM towards ABTS. It potently suppressed proliferation of tumor cell lines HepG2 and MCF7, and inhibited human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) with an IC50 value of 3.46 µM, 4.95 µM, and 5.85 µM, respectively, signifying that it is an antipathogenic protein.


Assuntos
Proliferação de Células/efeitos dos fármacos , Coprinus/enzimologia , Lacase/farmacologia , Neoplasias/tratamento farmacológico , Coprinus/química , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Transcriptase Reversa do HIV/biossíntese , Transcriptase Reversa do HIV/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Células Hep G2 , Humanos , Lacase/genética , Lacase/isolamento & purificação , Células MCF-7 , Micélio/química , Micélio/enzimologia , Neoplasias/patologia
5.
Appl Microbiol Biotechnol ; 98(8): 3475-94, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24562325

RESUMO

Marine organisms including bacteria, fungi, algae, sponges, echinoderms, mollusks, and cephalochordates produce a variety of products with antifungal activity including bacterial chitinases, lipopeptides, and lactones; fungal (-)-sclerotiorin and peptaibols, purpurides B and C, berkedrimane B and purpuride; algal gambieric acids A and B, phlorotannins; 3,5-dibromo-2-(3,5-dibromo-2-methoxyphenoxy)phenol, spongistatin 1, eurysterols A and B, nortetillapyrone, bromotyrosine alkaloids, bis-indole alkaloid, ageloxime B and (-)-ageloxime D, haliscosamine, hamigeran G, hippolachnin A from sponges; echinoderm triterpene glycosides and alkene sulfates; molluscan kahalalide F and a 1485-Da peptide with a sequence SRSELIVHQR; and cepalochordate chitotriosidase and a 5026.9-Da antifungal peptide. The antiviral compounds from marine organisms include bacterial polysaccharide and furan-2-yl acetate; fungal macrolide, purpurester A, purpurquinone B, isoindolone derivatives, alterporriol Q, tetrahydroaltersolanol C and asperterrestide A, algal diterpenes, xylogalactofucan, alginic acid, glycolipid sulfoquinovosyldiacylglycerol, sulfated polysaccharide p-KG03, meroditerpenoids, methyl ester derivative of vatomaric acid, lectins, polysaccharides, tannins, cnidarian zoanthoxanthin alkaloids, norditerpenoid and capilloquinol; crustacean antilipopolysaccharide factors, molluscan hemocyanin; echinoderm triterpenoid glycosides; tunicate didemnin B, tamandarins A and B and; tilapia hepcidin 1-5 (TH 1-5), seabream SauMx1, SauMx2, and SauMx3, and orange-spotted grouper ß-defensin. Although the mechanisms of antifungal and antiviral activities of only some of the aforementioned compounds have been elucidated, the possibility to use those known to have distinctly different mechanisms, good bioavailability, and minimal toxicity in combination therapy remains to be investigated. It is also worthwhile to test the marine antimicrobials for possible synergism with existing drugs. The prospects of employing them in clinical practice are promising in view of the wealth of these compounds from marine organisms. The compounds may also be used in agriculture and the food industry.


Assuntos
Antifúngicos/isolamento & purificação , Antivirais/isolamento & purificação , Organismos Aquáticos/química , Produtos Biológicos/isolamento & purificação , Antifúngicos/farmacologia , Antivirais/farmacologia , Produtos Biológicos/farmacologia
6.
J Basic Microbiol ; 54 Suppl 1: S102-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23787947

RESUMO

An RNase with a molecular mass of 28 kDa and with high ribonucleolytic activity toward poly(A) was purified from the ascocarps of Tuber indicum. The purification procedure involved ion exchange chromatography on diethylaminoethyl cellulose, Q-Sepharose and Mono Q, and gel filtration by fast protein liquid chromatography on Superdex 75. The pH and temperature optima of the RNase were 7.2 and 50 °C, respectively. The ranking of its activity toward various polyhomoribonucleotides was poly(A)>poly(C)>poly(G) ≈ poly(U). All of the metal ions used in this study, except for the K(+) ions, curtailed the activity of the RNase. The RNase activity was reduced by ethylene diamine tetraacetic acid (EDTA), dithiothreitol (DTT), and sodium dodecyl sulfate (SDS) by 42.2%, 75.5%, and 96.6%, respectively. The RNase inhibited the proliferation of hepatoma (HepG2) and human breast cancer cell lines (MCF7), with half-maximal inhibitory concentrations (IC50 ) of 12.6 and 16.6 µM, respectively.


Assuntos
Agaricales/enzimologia , Ascomicetos/enzimologia , Poli A/metabolismo , Ribonucleases/isolamento & purificação , Ribonucleases/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromatografia em Gel , Cromatografia por Troca Iônica , Inibidores Enzimáticos/metabolismo , Estabilidade Enzimática , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Metais/metabolismo , Peso Molecular , Ribonucleases/química , Especificidade por Substrato , Temperatura
7.
Biotechnol Appl Biochem ; 60(4): 393-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24033593

RESUMO

A 36-kDa protein, with an N-terminal sequence highly homologous to polygalacturonase (PG) inhibiting proteins, was isolated from small brown-eyed cowpea seeds. The protein was unadsorbed on diethylaminoethyl cellulose but adsorbed on both Affi-gel blue gel and SP-sepharose. It inhibited mycelial growth in the fungus Mycosphaerella arachidicola with an half-maximal (50%) inhibitory concentration (IC50 ) of 3.3 µM. It reduced [methyl-(3) H] thymidine incorporation into MBL2 lymphoma and L1210 leukemia cells with an IC50 of 7.4 and 5.4 µM, respectively. It inhibited human immunodeficiency virus type 1 (HIV-1) reverse transcriptase with an IC50 of 12.9 µM. However, it did not inhibit PG. The potent antifungal and antitumor activities of the protein suggest that it can be developed into an antifungal agent for combating M. arachidicola invasion in crops and an agent for cancer therapy in humans.


Assuntos
Antifúngicos/isolamento & purificação , Fabaceae/química , Transcriptase Reversa do HIV/antagonistas & inibidores , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Inibidores da Transcriptase Reversa/isolamento & purificação , Sementes/química , Sequência de Aminoácidos , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fungos/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/química , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia
8.
Indian J Biochem Biophys ; 50(3): 196-201, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23898482

RESUMO

A 15 kDa ribonuclease (RNase) was purified from dried fruiting bodies of the wild edible mushroom Armillaria luteo-virens. The simple 4-step purification protocol involved ion-exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on SP-Sepharose and a final gel filtration by FPLC on Superdex-75. The RNase was unadsorbed on Affi-gel blue gel, but adsorbed on DEAE-cellulose and SP-Sepharose. The N-terminal amino acid sequence of purified RNase was AGVQYKLTILLV, which showed low sequence homology to those of previously reported RNases. The optimal pH and temperature of the enzyme were very close to 4.0 and 70 degrees C, respectively. The enzyme showed considerably high ribonucleolytic activity and broad specificity towards polyhomoribonucleotides, with a specificity of poly(U) > poly(C) > poly (G) > poly(A). The ribonucleolytic activities towards poly(U), poly(C), poly(G) and poly(A) were 279.5, 184.1, 69.9 and 52.3 U/mg, respectively.


Assuntos
Agaricales/enzimologia , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Ribonucleases/química , Ribonucleases/isolamento & purificação , Animais , Ativação Enzimática , Estabilidade Enzimática , Especificidade por Substrato
9.
Biomed Res Int ; 2013: 540239, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23586045

RESUMO

A monomeric phytase with a molecular mass of 14 kDa was acquired from fresh fruiting bodies of the shiitake mushroom Lentinus edodes. The isolation procedure involved chromatography on DEAE-cellulose, CM-cellulose, Q-Sepharose, Affi-gel blue gel, and a final fast protein liquid chromatography-gel filtration on Superdex 75. The purified phytase demonstrated the unique N-terminal amino acid sequence DPKRTDQVN, which exhibited no sequence similarity with those of other phytases previously reported. It expressed its maximal activity at pH 5.0 and 37 °C. Phytase activity manifested less than 20% change in activity over the pH range of 3.0-9.0, considerable thermostability with more than 60% residual activity at 70 °C, and about 40% residual activity at 95°C. It displayed a wide substrate specificity on a variety of phosphorylated compounds with the following ranking: ATP > fructose-6-phosphate > AMP > glucose-6-phosphate > ADP > sodium phytate > ß -glycerophosphate. The phytase activity was moderately stimulated by Ca(2+), but inhibited by Al(3+), Mn(2+), Zn(2+), and Cu(2+) at a tested concentration of 5 mM.


Assuntos
6-Fitase/química , 6-Fitase/isolamento & purificação , Cogumelos Shiitake/enzimologia , Sequência de Aminoácidos , Cromatografia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Peso Molecular , Especificidade por Substrato , Temperatura
10.
J Basic Microbiol ; 53(10): 868-75, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23322529

RESUMO

A monomeric acid phosphatase (ACP) with a molecular mass of 72.5 kDa was purified from fresh fruiting bodies of cultured Schizophyllum commune mushroom. The isolation procedure entailed ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. It demonstrated a unique N-terminal amino acid sequence of NAPWAQIDEV, which exhibited 60% amino acid identity to that of S. commune hypothetical histidine ACP based on its genome sequence, but less than 30% amino acid identity to that of other fungal ACPs previously reported. The ACP exhibited an optimum temperature at 50 °C, an optimum pH at pH 4.6, and was considerably stable at a pH range of 4.0 to 9.0, and a temperature range of 20-40 °C. The Km of the purified enzyme for ρ-nitrophenyl phosphate (ρNPP) was 0.248 mM and the Vmax was 9.093 × 10(-3) µM/min. ACP activity was strongly inhibited by Al(3+) and Fe(3+) , but enhanced by Co(2+) , Mg(2+) , and Ca(2+) at a concentration of 0.5 mM.


Assuntos
Fosfatase Ácida/isolamento & purificação , Fosfatase Ácida/metabolismo , Carpóforos/enzimologia , Schizophyllum/enzimologia , Fosfatase Ácida/química , Sequência de Aminoácidos , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Carpóforos/fisiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Peso Molecular , Especificidade por Substrato , Temperatura
11.
Protein Pept Lett ; 20(7): 767-74, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23092133

RESUMO

A novel lectin was isolated from the dried fruiting bodies of the wild mushroom Paxillus involutus. Isolation was conducted by anion exchange chromatography on DEAE-Cellulose, Q-Sepharose and gel filtration on Superdex 75 using a fast protein liquid chromatography (FPLC) system. This lectin had a molecular mass of 28 kDa and was composed of four identical subunits, each with a molecular mass of 7 kDa. N-terminal amino acid sequence of the P. involutus lectin was determined to be CTCAVFLNNTTVKS, which showed a low level of similarity to mushroom lectin sequences reported previously. The biochemical properties of this lectin were determined, and the hemagglutinating activity was inhibited by inulin and O-Nitrophenyl-ß-D-galacto-pyranoside. Additionally, Ca2+, Zn2+, Cd2+, Fe2+, and Al3+ inhibited its hemagglutinating activity, while Cu2+ promoted this activity. This lectin exhibited poor thermostability and was sensitive to HCl, but it had a high tolerance to NaOH exposure. In terms of biological properties, this lectin manifested antiphytovirus activity towards tobacco mosaic virus (TMV) with a 70.61% inhibition at a concentration of 200 µg/mL. This lectin was devoid of inhibitory activities toward pathogenic fungi and HIV-1 reverse transcriptase, and antiproliferative activities were observed in tumor cell lines including lung cancer A-549 and human colon cancer HCT-8 cells.


Assuntos
Agaricus/química , Proteínas Fúngicas/química , Lectinas/química , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Carboidratos/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/farmacologia , Lectinas/isolamento & purificação , Lectinas/farmacologia , Metais/química , Estabilidade Proteica , Vírus do Mosaico do Tabaco/efeitos dos fármacos
12.
J Biomed Biotechnol ; 2012: 736472, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23093860

RESUMO

A novel 68 kDa laccase was purified from the mycorrhizal fungus Agaricus placomyces by utilizing a procedure that comprised three successive steps of ion exchange chromatography and gel filtration as the final step. The monomeric enzyme exhibited the N-terminal amino acid sequence of DVIGPQAQVTLANQD, which showed only a low extent of homology to sequences of other fungal laccases. The optimal temperature for A. placomyces laccase was 30°C, and optimal pH values for laccase activity towards the substrates 2,7'-azinobis[3-ethylbenzothiazolone-6-sulfonic acid] diammonium salt (ABTS) and hydroquinone were 5.2 and 6.8, respectively. The laccase displayed, at 30°C and pH 5.2, K(m) values of 0.392 mM towards hydroquinone and 0.775 mM towards ABTS. It potently suppressed proliferation of MCF 7 human breast cancer cells and Hep G2 hepatoma cells and inhibited human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) activity with an IC(50) of 1.8 µM, 1.7 µM, and 1.25 µM, respectively, signifying that it is an antipathogenic protein.


Assuntos
Agaricus/enzimologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Lacase/administração & dosagem , Lacase/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Inibidores da Transcriptase Reversa/química , Proliferação de Células/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/farmacologia , Células Hep G2 , Humanos , Células MCF-7 , Neoplasias Experimentais/patologia
13.
Acta Biochim Pol ; 59(3): 407-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22946027

RESUMO

A novel laccase with a molecular mass of 64 kDa and the N-terminal sequence AIGPDDTINF was isolated from fresh fruiting bodies of the mushroom Pleurotus nebrodensis. The purification protocol comprised ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-Sepharose, and gel filtration on Superdex 75. The laccase was adsorbed on DEAE-cellulose and Q-Sepharose, but not on CM-cellulose. It demonstrated an optimal temperature of 70°C. The enzyme activity increased steadily over the temperature range 20°C-70°C. There was only a slight reduction in activity at 80°C. However, all activity disappeared following exposure to 100°C for 10 minutes. The enzyme activity changed only slightly over the pH range 3-5, with the optimum at pH 5, but underwent a precipitous decline when the pH was elevated to 6, and was undetectable at pH 8 and pH 9.


Assuntos
Proteínas Fúngicas/isolamento & purificação , Lacase/isolamento & purificação , Pleurotus/enzimologia , Adsorção , Sequência de Aminoácidos , Catecóis/química , Cromatografia DEAE-Celulose/métodos , Cromatografia em Gel/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Ativação Enzimática , Ensaios Enzimáticos/métodos , Carpóforos/enzimologia , Proteínas Fúngicas/química , Concentração de Íons de Hidrogênio , Lacase/química , Peso Molecular , Fenilenodiaminas/química , Pirogalol/química , Análise de Sequência de Proteína/métodos , Especificidade por Substrato , Temperatura
14.
J Biomed Biotechnol ; 2012: 728975, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22675256

RESUMO

A novel aspartic protease with HIV-1 RT inhibitory activity was isolated and characterized from fruiting bodies of the wild mushroom Xylaria hypoxylon. The purification protocol comprised distilled water homogenization and extraction step, three ion exchange chromatographic steps (on DEAE-cellulose, Q-Sepharose, and CM-cellulose in succession), and final purification was by FPLC on Superdex 75. The protease was adsorbed on all the three ion exchangers. It was a monomeric protein with a molecular mass of 43 kDa as estimated by SDS-PAGE and FPLC. Its N-terminal amino acid sequence was HYTELLSQVV, which exhibited no sequence homology to other proteases reported. The activity of the protease was adversely affected by Pepstatin A, indicating that it is an aspartic protease. The protease activity was maximal or nearly so in the pH range 6-8 and in the temperature range 35-60°C. The purified enzyme exhibited HIV-1 RT inhibitory activity with an IC50 value of 8.3 µM, but was devoid of antifungal, ribonuclease, and hemagglutinating activities.


Assuntos
Ácido Aspártico Proteases/metabolismo , Ácido Aspártico Proteases/farmacologia , Carpóforos/enzimologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Xylariales/enzimologia , Ácido Aspártico Proteases/química , Ácido Aspártico Proteases/isolamento & purificação , Caseínas/metabolismo , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Carpóforos/química , Concentração de Íons de Hidrogênio , Análise de Sequência de Proteína , Temperatura , Xylariales/química
15.
Expert Opin Pharmacother ; 13(12): 1695-705, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22716311

RESUMO

INTRODUCTION: Invasive fungal infection (IFI) is a serious problem due to difficulties in early diagnosis and high mortality. Different approaches are adopted for the treatment and management of IFI, including prophylactic, empiric, preemptive and directed strategies. AREAS COVERED: This paper reviews the type of pharmacotherapy used for antifungal prophylaxis in infants with extremely low birth weights, pediatric patients with cardiac disease, preterm neonates, pediatric oncology patients, adult cancer patients with neutropenia, adult patients with hematologic malignancy, hematopoietic stem-cell transplantation recipients, organ transplant recipients, HIV-infected patients, immunosuppressed patients treated with moderate or high doses of corticosteroids, and patients with invasive fusariosis, candidemia, invasive candidiasis, systemic mycoses and immunocompromised patients. EXPERT OPINION: Azole drugs are the drugs most often used in cost-effective antifungal prophylaxis of patients with conditions such as immunodeficiency and cancer, which render them highly susceptible to IFI. Fluconazole is the most outstanding example. However, there are many azoles with different pharmacological characteristics that the physician can choose from. Echinocandins have favorable characteristics that make them useful for treating Candida infections. Antibodies, or their engineered derivatives directed against cell-wall polysaccharides and glycopeptides, and some protein epitopes of Candida albicans, appear to be a promising novel approach for prophylaxis against Candida infection and deserve further in-depth investigations.


Assuntos
Antifúngicos/uso terapêutico , Micoses/prevenção & controle , Azóis/uso terapêutico , Humanos , Hospedeiro Imunocomprometido
16.
J Biomed Biotechnol ; 2012: 536725, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22536022

RESUMO

A 59 kDa laccase with inhibitory activity against HIV-1 reverse transcriptase (IC(50) = 2.4 µM) was isolated from the broth of mycelial culture of the mushroom Lentinus tigrinus. The isolation procedure involved ion exchange chromatography on DEAE-cellulose and CM-cellulose, and gel filtration by fast protein liquid chromatography on Superdex 75. The laccase was adsorbed on both types of ion exchangers. About 95-fold purification was achieved with a 25.9% yield of the enzyme. The procedure resulted in a specific enzyme activity of 76.6 U/mg. Its N-terminal amino acid sequence was GIPDLHDLTV, which showed little similarity to other mushroom laccase and other Lentinus tigrinus strain laccase. Its characteristics were different from previously reported laccase of other Lentinus tigrinus strain. Maximal laccase activity was observed at a pH of 4 and at a temperature of 60°C, respectively. This study yielded the information about the potentially exploitable activities of Lentinus tigrinus laccase.


Assuntos
Proteínas Fúngicas/farmacologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Lacase/farmacologia , Lentinula/enzimologia , Inibidores da Transcriptase Reversa/farmacologia , Sequência de Aminoácidos , Cromatografia por Troca Iônica , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Lacase/isolamento & purificação , Lacase/metabolismo , Lentinula/química , Dados de Sequência Molecular , Micélio/química , Micélio/enzimologia , Inibidores da Transcriptase Reversa/isolamento & purificação , Inibidores da Transcriptase Reversa/metabolismo , Temperatura
17.
J Microbiol ; 50(1): 72-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22367940

RESUMO

A novel laccase from the edible mushroom Hericium coralloides was purified by ion exchange chromatography on diethylaminoethyl (DEAE) cellulose, carboxymethyl (CM) cellulose, and Q-Sepharose columns followed by fast protein liquid chromatography gel filtration on a Superdex 75 column. Analysis by gel filtration and SDS-PAGE indicated that the protein is a monomer in solution with a molecular mass of 65 kDa. Its N-terminal amino acid sequence was AVGDDTPQLY, which exhibits partial sequence homology to previously isolated laccases. Optimum activity was observed at pH 2.2 and at 40°C. The enzyme showed activity toward a variety of substrates, the most sensitive of which was 2,2'-azinobis [3-ethylbenzothiazolone-6-sulfonic acid] diammonium salt (ABTS). The degradation activity toward substrates was ABTS > N,N-dimethyl-1,4-phenylenediamine > catechol > 2-methylcatechol > pyrogallol. The laccase did not exert any antiproliferative activity against Hep G2 or MCF 7 tumor cell lines at a concentration of 60 µM, unlike some previously reported mushroom proteins, but showed significant activity toward human immunodeficiency virus-1 (HIV-1) reverse transcriptase with an IC(50) of 0.06 µM.


Assuntos
Basidiomycota/enzimologia , Lacase/isolamento & purificação , Lacase/metabolismo , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Transcriptase Reversa do HIV/antagonistas & inibidores , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Lacase/química , Peso Molecular , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/isolamento & purificação , Inibidores da Transcriptase Reversa/metabolismo , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Temperatura
18.
J Biosci Bioeng ; 113(1): 42-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22014786

RESUMO

A novel serine protease, designated as cordysobin, was purified from dried fruiting bodies of the mushroom Cordyceps sobolifera. The isolation procedure utilized ion exchange chromatography on DEAE-cellulose and SP-Sepharose followed by gel filtration on Superdex 75. The protease did not adsorb on DEAE-cellulose but bound to SP-Sepharose. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), the protease resolved as a single band with an apparent molecular mass of 31 kDa. Its optimal pH was 10.0, and the optimal temperature was 65°C. The protease displayed a K(m) value of 0.41 µM and 13.44 µM·min⁻¹ using Suc-Leu-Leu-Val-Tyr-MCA as substrate at pH 10.0 and 37°C. Protease activity was enhanced by the Fe²âº ion at low concentration range of 1.25-10 mM and was strongly inhibited by Hg²âº up to 1.25 mM. The protease was strongly inhibited by chymostatin and phenylmethylsulfonyl fluoride (PMSF), suggesting that it is a serine protease. It manifested significant inhibitory activity toward HIV-1 reverse transcriptase (RT) with an IC50 value of 8.2×10⁻³ µM, which is the highest anti-HIV-1 RT activity of reported mushroom proteins.


Assuntos
Fármacos Anti-HIV/farmacologia , Cordyceps/enzimologia , Proteínas Fúngicas/farmacologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Serina Proteases/farmacologia , Fármacos Anti-HIV/isolamento & purificação , Cromatografia em Gel , Cromatografia por Troca Iônica , Cumarínicos , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Carpóforos/enzimologia , Proteínas Fúngicas/isolamento & purificação , HIV-1/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Espectrometria de Massas , Peso Molecular , Oligopeptídeos , Serina Proteases/isolamento & purificação , Temperatura
19.
J Microbiol ; 49(5): 803-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22068498

RESUMO

A 20-kDa ribonuclease (RNase) was purified from fresh fruiting bodies of cultured Schizophyllum commune mushrooms. The RNase was not adsorbed on Affi-gel blue gel but adsorbed on DEAE-cellulose and CM-cellulose. It exhibited maximal RNase activity at pH 6.0 and 70°C. It demonstrated the highest ribonucleolytic activity toward poly (U) (379.5 µ/mg), the second highest activity toward poly (C) (244.7 µ/mg), less activity toward poly (A) (167.4 µ/mg), and much weaker activity toward poly (G) (114.5 µ/mg). The RNase inhibited HIV-1 reverse transcriptase with an IC(50) of 65 µM. No effect on [(3)H-methyl]-thymidine uptake by lymphoma MBL2 cells and leukemia L1210 cells was observed at 100 µM concentration of the RNase. A comparison of RNases from S. commune and Volvariella volvacea revealed that they demonstrated some similarities in N-terminal amino acid sequence, optimum pH and polyhomoribonucleotide specificity. However, some differences in chromatographic behavior and molecular mass were observed.


Assuntos
Transcriptase Reversa do HIV/antagonistas & inibidores , Ribonucleases/isolamento & purificação , Ribonucleases/metabolismo , Schizophyllum/enzimologia , Linhagem Celular Tumoral , Estabilidade Enzimática , Carpóforos/enzimologia , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Peso Molecular , Poli A/metabolismo , Poli C/metabolismo , Poli G/metabolismo , Poli U/metabolismo , Ribonucleases/química , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Temperatura
20.
J Biosci Bioeng ; 111(6): 641-5, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21388873

RESUMO

A novel serine protease, with a molecular mass of 19 kDa and the N-terminal sequence of ARTPEAPAEV, was isolated from dried fruiting bodies of the mushroom Pholiota nameko. The purification protocol comprised ion exchange chromatography on DEAE-cellulose, Q-Sepharose and SP-Sepharose, and gel filtration on Superdex 75. It was unadsorbed on DEAE-cellulose and Q-Sepharose but adsorbed on SP-Sepharose. It exhibited an optimum temperature at 50°C, an optimum pH at pH 8.8, a Km of 5.64 mg/mL and a Vmax of 0.98 µmol/min/mL against substrate casein. A number of metal ions inhibited the enzyme including Pb(2+), Mn(2+), Ca(2+), Hg(2+), Zn(2+), Cu(2+), Co(2+), Fe(3+) and Al(3+), with the inhibition of the last two cations being the most potent. K(+) and Mg(2+) slightly enhanced, while Li(+) moderately potentiated the activity of the protease. The protease was strongly inhibited by phenylmethylsulfonyl fluoride (PMSF), suggesting that it is a serine protease.


Assuntos
Agaricales/enzimologia , Pholiota/enzimologia , Serina Proteases/metabolismo , Sequência de Aminoácidos , Cromatografia em Gel , Cromatografia por Troca Iônica , Estabilidade Enzimática , Carpóforos/enzimologia , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peso Molecular , Homologia de Sequência de Aminoácidos , Serina Proteases/isolamento & purificação , Temperatura
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