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1.
J Basic Microbiol ; 59(12): 1238-1247, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613018

RESUMO

Penicillium griseoroseum lectin was 80-fold purified by successive DEAE Sepharose anion exchange and Sephadex G-100 gel permeation chromatography. P. griseoroseum lectin exhibited haemagglutination activity towards protease-treated rabbit erythrocytes. It showed specificity towards various carbohydrates such as d-mannose, N-acetyl-d-glucosamine, mucins, and so forth. P. griseoroseum lectin was found as a glycoprotein with glycan content of 4.33%. Purified P. griseoroseum lectin is homodimeric having a molecular mass of 57 kDa with subunit molecular mass of 28.6 kDa. Haemagglutination activity of purified P. griseoroseum lectin was completely stable from 25°C to 35°C at a pH range of 6-7.5. Lectin activity was not influenced by divalent metal ions and denaturants. P. griseoroseum lectin manifested mitogenicity towards mice splenocytes and activity reached a peak at 75 µg/ml of lectin concentration. P. griseoroseum lectin in microgram concentrations stimulated proliferation of mice splenocytes. Thus, P. griseoroseum lectin exhibits potential mitogenicity, which can be exploited for further biomedical applications.


Assuntos
Lectinas/química , Lectinas/isolamento & purificação , Mitógenos/química , Mitógenos/isolamento & purificação , Penicillium/química , Animais , Carboidratos/química , Cátions/metabolismo , Proliferação de Células/efeitos dos fármacos , Quelantes , Glicoproteínas/química , Hemaglutinação , Concentração de Íons de Hidrogênio , Lectinas/farmacologia , Masculino , Camundongos , Mitógenos/farmacologia , Peso Molecular , Multimerização Proteica , Estabilidade Proteica , Temperatura
2.
Biosens Bioelectron ; 143: 111607, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31445384

RESUMO

As a well-known allergenic indicator in kidney beans, lectins have always been the serious threats for human health. Herein, we introduced a new label-free voltammetric immunosensor for the direct determination of kidney bean lectin (KBL) with potential allergenic activity. Gold nanoparticles-polyethyleneimine-multiwalled carbon nanotubes nanocomposite was one-pot synthesized and modified onto the glass carbon electrode to enhance catalytic currents of oxygen reduction reaction. The KBL polyclonal antibody, acquired from rabbit immunization, was orientedly immobilized on the electrode modified with recombinant staphylococcal protein A via fragment crystallizable (Fc) region of antibody. Under the optimized condition, the immunosensor displayed a good linear response (R2 = 0.978) to KBL with a range from 0.05 to 100 µg/mL and a detection limit of 0.023 µg/mL. Simultaneously, the immunosensor exhibited well selectivity, interference-resistant ability, stability (4 °C) and reproducibility. Compared with the conventional enzyme-linked immunosorbent assay (ELISA) method, the immunosensor was successfully applied to quantify allergenic activity of lectin in raw and cooked (boiled for 30 min) kidney bean milk samples. This new approach provides new perspectives both for rapid quantification of lectin in kidney beans-derived foodstuffs and as a real-time monitoring tool for the allergenic potential during the whole production and consumption process.


Assuntos
Alérgenos/isolamento & purificação , Técnicas Biossensoriais , Lectinas/isolamento & purificação , Alérgenos/imunologia , Animais , Ouro/química , Humanos , Proteínas Imobilizadas/química , Proteínas Imobilizadas/imunologia , Lectinas/imunologia , Nanopartículas Metálicas/química , Nanotubos de Carbono/química , Coelhos
3.
Curr Pharm Biotechnol ; 20(15): 1236-1243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333121

RESUMO

BACKGROUND: The immune system is responsible for providing protection to the body against foreign substances. The immune system divides into two types of immune responses to study its mechanisms of protection: 1) Innate and 2) Adaptive. The innate immune response represents the first protective barrier of the organism that also works as a regulator of the adaptive immune response, if evaded the mechanisms of the innate immune response by the foreign substance the adaptive immune response takes action with the consequent antigen neutralization or elimination. The adaptive immune response objective is developing a specific humoral response that consists in the production of soluble proteins known as antibodies capable of specifically recognizing the foreign agent; such protective mechanism is induced artificially through an immunization or vaccination. Unfortunately, the immunogenicity of the antigens is an intrinsic characteristic of the same antigen dependent on several factors. CONCLUSION: Vaccine adjuvants are chemical substances of very varied structure that seek to improve the immunogenicity of antigens. The main four types of adjuvants under investigation are the following: 1) Oil emulsions with an antigen in solution, 2) Pattern recognition receptors activating molecules, 3) Inflammatory stimulatory molecules or activators of the inflammasome complex, and 4) Cytokines. However, this paper addresses the biological plausibility of two phytochemical compounds as vaccine adjuvants: 5) Lectins, and 6) Plant phenolics whose characteristics, mechanisms of action and disadvantages are addressed. Finally, the immunological usefulness of these molecules is discussed through immunological data to estimate effects of plant phenolics and lectins as vaccine adjuvants, and current studies that have implanted these molecules as vaccine adjuvants, demonstrating the results of this immunization.


Assuntos
Adjuvantes Imunológicos/farmacologia , Lectinas/farmacologia , Plantas/química , Polifenóis/farmacologia , Imunidade Adaptativa/efeitos dos fármacos , Adjuvantes Imunológicos/isolamento & purificação , Animais , Antígenos/imunologia , Citocinas/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Lectinas/imunologia , Lectinas/isolamento & purificação , Polifenóis/imunologia , Polifenóis/isolamento & purificação , Vacinação/métodos , Vacinas/imunologia
4.
An Acad Bras Cienc ; 91(2): e20180991, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241705

RESUMO

Dalbergieae tribe lectins, possessing binding affinity for galactose and mannose, present inflammatory and nociceptive effects, while those for N-acetylglucosamine are anti-inflammatory. Since the anti-inflammatory effect of the seed lectin of L. araripensis (LAL) had been already demonstrated in mice, this effect was presently evaluated in rat models of acute inflammation. LAL (0.01-1 mg/kg) was administered by intravenous (i.v.) route in male Wistar rats 30 min before paw edema induction by dextran or carrageenan, and peritonitis by carrageenan. LAL (1 mg/kg) was incubated with N-acetylglucosamine for allowing lectin-sugar interactions before injection into animals. LAL toxicity was evaluated by the parameters: body mass, organs weight, stomach macroscopy, hematological and biochemical dosage. Statistical analysis was performed by ANOVA and Bonferroni's test (p<0.05). The paw edema induced by carrageenan (AUC: 0.96 ± 0.09) was inhibited by LAL about 39% (0-2 h) at all doses, and about 72% (3-5 h) at 0.1 and 1 mg/kg. The increase in the neutrophil migration stimulated by carrageenan was also inhibited by LAL (83%). In both models, LAL inhibitory effect was prevented by GlcNAc. The sub-chronic treatment with LAL was well tolerated by animals. LAL possesses anti-inflammatory effect via lectin domain, indicating potential modulator role in cellular inflammatory events.


Assuntos
Edema/tratamento farmacológico , Fabaceae/química , Inflamação/tratamento farmacológico , Lectinas/farmacologia , Doença Aguda , Animais , Carragenina , Modelos Animais de Doenças , Fabaceae/classificação , Lectinas/isolamento & purificação , Masculino , Ratos , Ratos Wistar
5.
Nat Commun ; 10(1): 2183, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31097723

RESUMO

Pseudomonas aeruginosa biofilms are composed of exopolysaccharides (EPS), exogenous DNA, and proteins that hold these communities together. P. aeruginosa produces lectins LecA and LecB, which possess affinities towards sugars found in matrix EPS and mediate adherence of P. aeruginosa to target host cells. Here, we demonstrate that LecB binds to Psl, a key matrix EPS, and this leads to increased retention of both cells and EPS in a growing biofilm. This interaction is predicted to occur between the lectin and the branched side chains present on Psl. Finally, we show that LecB coordinates Psl localization in the biofilm. This constitutes a unique function for LecB and identifies it as a matrix protein that contributes to biofilm structure through EPS interactions.


Assuntos
Biofilmes , Lectinas/metabolismo , Polissacarídeos Bacterianos/metabolismo , Pseudomonas aeruginosa/fisiologia , Microscopia Intravital , Lectinas/isolamento & purificação , Microscopia Confocal , Simulação de Acoplamento Molecular
6.
Int J Biol Macromol ; 134: 487-497, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31051203

RESUMO

An L-fucose specific lectin from pathogenic fungus Aspergillus niger isolated from the corneal smears of keratitis patient was purified in a single step using mucin coupled sepharose-4B column by 58-fold. The purified lectin, ANL has molecular mass of 30 kDa by SDS-PAGE and 31.6 kDa by ESI-MS. ANL is a glycoprotein with 2.59% carbohydrate. ANL is blood group nonspecific and also agglutinates rabbit erythrocytes. ANL is heat stable up to 50 °C and over a pH range of 7-10. Hapten inhibition studies revealed that ANL is specific to L-fucose, galactose, lactose and glycoproteins, showing highest MIC of 3.125 µg for L-fucose, mucin and fetuin. ANL has potent antibacterial activity against Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli and also it inhibits the biofilm formation by them. ANL showed strong binding to human pancreatic adenocarcinoma PANC-1 cells which was effectively blocked by L-fucose and mucin respectively by 76.2% and 84.2%. ANL showed dose and time dependent growth inhibitory effect on PANC-1 cells with IC50 of 1.25 µg/ml at 48 h. Effect of ANL was compared with another fucose specific lectin AOL, from Aspergillus oryzae showing an IC50 of 1.85 µg/ml at 48 h revealing promising clinical potential of ANL.


Assuntos
Aspergilose/microbiologia , Aspergillus niger/química , Fucose/metabolismo , Ceratite/microbiologia , Lectinas/isolamento & purificação , Lectinas/metabolismo , Animais , Linhagem Celular Tumoral , Eritrócitos , Humanos , Concentração de Íons de Hidrogênio , Lectinas/química , Camundongos , Peso Molecular , Ligação Proteica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura
7.
Int J Biol Macromol ; 130: 399-406, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30822473

RESUMO

The lectin from Latiporus sulphureus (LSL) was purified by chromatography. Five components were obtained, of which LSL4 was the most effective one to promote cell growth, which increased cell viability to 2.6 times and 0.8 times of negative control and positive control group, so LSL4 with the highest immunomodulatory activity was selected for further identification. In addition, its immune effects on murine macrophages in vitro were evaluated. After LSL4 treatment, cell viability and phagocytic activity were greatly improved, and NO amount could reach about 24.795 ±â€¯1.559 µmol·L-1. The contents of TNF-α and IL-10 were 4.0 and 3.2 times higher than those of the negative control group, and the contents of IL-1ß and IL-6 were 2.8 and 4.1 times higher than those of the negative control group, respectively. TAK242 significantly inhibited the secretion of TNF-α, IL-1ß, IL-6 and IL-10, with inhibition rates of 53%, 61%, 48% and 54%, respectively. The results showed that 76.0 kD glycoprotein could promote cell proliferation and phagocytosis, and activate cells to release more nitric oxide, nitric oxide synthase and cytokines. The lectin has potential immunopotentiation in functional foods and pharmacology.


Assuntos
Agaricales/química , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Lectinas/química , Lectinas/farmacologia , Sequência de Aminoácidos , Animais , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Fatores Imunológicos/isolamento & purificação , Lectinas/isolamento & purificação , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , Análise Espectral
8.
Arch Biochem Biophys ; 664: 149-156, 2019 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-30772259

RESUMO

A new mannose/N-acetyl-dglucosamine-specific lectin, named MaL, was purified from seeds of Machaerium acutifolium by precipitation with ammonium sulfate, followed by affinity and ion-exchange chromatography. MaL haemagglutinates either native rabbit erythrocytes or those treated with proteolytic enzymes. MaL is highly stable by the ability to maintain its haemagglutinating activity after exposure to temperatures up to 50 °C. The lectin haemagglutinating activity was optimum between pH 6.0 and 7.0 and inhibited after incubation with d-mannose and N-acetyl-d-glucosamine and α-methyl-d-mannopyranoside. MaL is a glycoprotein with relative molecular mass of 29 kDa (α-chain), 13 kDa (ß-chain) and 8 kDa (γ-chain) with secondary structure composed of 3% α-helix, 44% ß-sheet, 21% ß-turn, and 32% coil. The orofacial antinociceptive activity of the lectin was also evaluated. MaL (0.03 mg mL-1) reduced orofacial nociception induced by capsaicin, an effect that occurred via carbohydrate recognition domain interaction, suggesting an interaction of MaL with the transient receptor potential cation channel subfamily V member 1 (TRPV1) receptor. Our results confirm the potential pharmacological relevance of MaL as an inhibitor of acute orofacial mediated by TRPV1.


Assuntos
Acetilglucosamina/química , Fabaceae/química , Dor Facial/tratamento farmacológico , Lectinas/isolamento & purificação , Lectinas/uso terapêutico , Manose/química , Canais de Cátion TRPV/metabolismo , Sequência de Aminoácidos , Animais , Fenômenos Biofísicos , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Feminino , Lectinas/química , Masculino , Estrutura Secundária de Proteína , Coelhos , Espectrometria de Massas em Tandem , Peixe-Zebra
9.
Int J Biol Macromol ; 128: 124-131, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30682480

RESUMO

In the present study, Penicillium proteolyticum lectin was purified by DEAE-Sepharose chromatography followed by Sephadex G-100 gel filtration chromatography. A sequence of ion-exchange and gel filtration chromatography resulted in 52.30 fold purified lectin with a high yield of 84.21%. The purified P. proteolyticum lectin is a glycoprotein with 2.83% linked carbohydrates. A single band in Native-PAGE, whereas two bands (25.1 kDa and 22.9 kDa) in SDS-PAGE confirmed the heterodimeric nature of the purified lectin. The apparent molecular weight (48 kDa) of P. proteolyticum lectin was further confirmed by gel filtration analysis. Heterodimeric P. proteolyticum lectin was stable within a pH range of 6.5-7.5 and upto a temperature of 30 °C. The lectin activity was strongly inhibited by complex glycoproteins and denaturants. Metal ions are not required for agglutination activity of purified lectin. The lectin showed significant mitogenic response towards mice splenocytes. It exhibited highest mitogenic activity at a concentration of 50 µg/mL. This is a first report on characteristics of purified P. proteolyticum lectin having potent mitogenic potential.


Assuntos
Lectinas/química , Lectinas/farmacologia , Penicillium/química , Multimerização Proteica , Animais , Quelantes/química , Quelantes/farmacologia , Cromatografia em Gel , Cromatografia por Troca Iônica , Concentração de Íons de Hidrogênio , Lectinas/isolamento & purificação , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/metabolismo , Camundongos , Peso Molecular , Estabilidade Proteica , Temperatura
10.
J Appl Microbiol ; 126(1): 300-310, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30240117

RESUMO

AIM: A lectin Concanavalin A (ConA) derived from Canavalia ensiformis (jack bean) exhibits high-binding affinity to carbohydrates on bacterial cell surfaces. The objective of this study was to inhibit the biofilm formation of the foodborne pathogens enterohemorrhagic Escherichia coli and Listeria monocytogenes using ConA prepared by a membrane-based extraction method. METHODS AND RESULTS: ConA was extracted using a simple and inexpensive membrane method instead of a chromatography approach. The extracted ConA was effective in inhibiting biofilms of E. coli by 30-fold and L. monocytogenes by 140-fold. In addition, ConA decreased the swimming motility of enterohemorrhagic E. coli EDL933 (EHEC) by 37%, resulting in low biofilm formation, as ConA binding to the bacterial cell surfaces might cause a reduced capability to adhere due to low cellular motility. We confirmed that the extracted ConA contains active components at less than 10 kDa as well as ConA multimers (>30 kDa) that repress EHEC biofilms. Additionally, noncell-based mannose reduced the activity of ConA in inhibiting biofilms. CONCLUSIONS: ConA extracted using the membrane-based method is active in inhibiting the biofilm formation by E. coli and L. monocytogenes via the mannose-binding affinity of ConA. SIGNIFICANCE AND IMPACT OF THE STUDY: ConA can be used as a promising anti-adherent and antibiofilm agent in inhibiting biofilm formation by enterohemorrhagic E. coli and L. monocytogenes. The membrane-based extraction approach may be applied for the economic production of biologically active lectins.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Canavalia/química , Escherichia coli Êntero-Hemorrágica/efeitos dos fármacos , Lectinas/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Lectinas/isolamento & purificação
11.
Int J Biol Macromol ; 126: 291-297, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30583005

RESUMO

Lectins are carbohydrate-binding proteins broadly distributed in plants and have several biological functions, including antimicrobial action. Portulaca elatior is a Caatinga plant whose chemical composition and biotechnological potential have not been extensively studied. In this work, a lectin was isolated from P. elatior root extract and evaluated for antimicrobial activity. The P. elatior root lectin (PeRoL) showed native molecular mass of 33 kDa, pI 3.8 and is comprised of two subunits of 15 kDa linked by disulfide bonds. No sequence similarities with Viridiplantae proteins were observed. The PeRoL hemagglutinating activity (HA) was not affected by heating and was detected in a pH ranging from 4.0 to 8.0. Trehalose was identified as an endogenous inhibitor of PeRoL present in the roots. Bacteriostatic activity was detected against Enterococcus faecalis, Pseudomonas aeruginosa and Staphylococcus aureus (minimal inhibitory concentration of 8.1, 32.5 and 4.06 µg/mL, respectively). PeRoL induced the death of Candida albicans, Candida parapsilosis, Candida krusei, and Candida tropicalis cells, with a minimal fungicidal concentration of 16 µg/mL. The lectin (100 µg/mL) was not cytotoxic to human peripheral blood mononuclear cells (PBMCs) and did not show hemolytic activity. In conclusion, the roots of P. elatior contain a trehalose-binding, thermostable, and antimicrobial lectin.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Lectinas/farmacologia , Raízes de Plantas/química , Portulaca/química , Trealose/metabolismo , Sequência de Aminoácidos , Hemaglutinação/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Lectinas/isolamento & purificação , Peptídeos/química , Extratos Vegetais/farmacologia , Ligação Proteica
12.
Amino Acids ; 51(2): 345-353, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30353357

RESUMO

The diversity of defensive peptides from skin of amphibians has been demonstrated. These peptides may have resulted from the diversity of microorganisms encountered by amphibians. In this study, peptidomics and RNA sequencing analyses were used to study deeply the defensive peptides of the skin secretions from Polypedates megacephalus. A total of 99 defensive peptides have been identified from the skin secretions. Among these peptides, 3 peptides were myotropical peptides and 34 peptides classified as protease inhibitor peptides. 5 lectins, 8 antimicrobial peptides, 26 immunomodulatory peptides, 10 wound-healing peptides and 13 other bioactive peptides were identified as belonging to the innate immune system. One antimicrobial peptide Pm-amp1 showed high similarity to antimicrobial peptide marcin-18. This peptide was successfully expressed and showed moderate activity against four tested strains. These identified peptides highlight the extensive diversity of defensive peptides and provide powerful tools to understand the defense weapon of frog.


Assuntos
Proteínas de Anfíbios/química , Proteínas de Anfíbios/genética , Venenos de Anfíbios/química , Venenos de Anfíbios/genética , Anuros/fisiologia , Pele/química , Proteínas de Anfíbios/isolamento & purificação , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Feminino , Fatores Imunológicos/genética , Fatores Imunológicos/isolamento & purificação , Lectinas/genética , Lectinas/isolamento & purificação , Masculino , Espectrometria de Massas , Inibidores de Proteases/química , Inibidores de Proteases/isolamento & purificação , Análise de Sequência de Proteína , Análise de Sequência de RNA , Sequenciamento Completo do Exoma
13.
Int J Biol Macromol ; 124: 819-827, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30496858

RESUMO

We studied localization and physiological activities of a lectin showing specific binding to N-acetylhexosamines, termed HOL-18, purified from Japanese black sponge (Halichondria okadai). Antiserum against the lectin was generated in rabbit and applied for immunohistochemical analyses. HOL-18 was expressed specifically around water pores and on spicules of sponge tissues. It showed strong binding to a variety of N-acetylhexosamines: N-acetyl D-glucosamine, N-acetyl D-galactosamine, N-acetyl mannosamine, N-acetyl muramic acid, and N-acetyl neuraminic acid. Hemagglutination induced by the lectin was inhibited by lipopolysaccharides and a peptidoglycan. HOL-18 inhibited growth of a gram-positive bacterium (Listeria monocytogenes), gram-negative bacteria (Escherichia coli, Shigella boydii, Pseudomonas aeruginosa), and a fungus (Aspergillus niger). It displayed anti-biofilm activity against P. aeruginosa. HOL-18 was internalized into conidiophores of A. niger, and displayed notable antifungal activity. Fluorescence microscopy revealed binding and incorporation of the lectin into human cancer cell lines HeLa, MCF-7, and T47D, but not Caco-2. HOL-18 displayed dose-dependent cytotoxic effects against HeLa, MCF-7, and T47D, with respective IC50 values 40, 52, and 63 µg/mL. In HeLa cells, it activated phosphorylation of MAPK pathway molecule (ERK1/2) and activated caspase-3 to trigger apoptosis. HOL-18 thus has the potential to upregulate metabolic pathways in higher animal cells through binding to N-acetylhexosamines.


Assuntos
Anti-Infecciosos/química , Antineoplásicos/química , Hexosaminas/química , Lectinas/química , Poríferos/química , Animais , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Caspase 3/genética , Caspase 3/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Células HeLa , Testes de Hemaglutinação , Hexosaminas/metabolismo , Humanos , Lectinas/isolamento & purificação , Lectinas/metabolismo , Lectinas/farmacologia , Lipopolissacarídeos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Células MCF-7 , Testes de Sensibilidade Microbiana , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Peptidoglicano/farmacologia , Fosforilação/efeitos dos fármacos , Ligação Proteica , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Coelhos , Shigella boydii/efeitos dos fármacos , Shigella boydii/crescimento & desenvolvimento
14.
Int J Biol Macromol ; 125: 53-60, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30500503

RESUMO

Lonchocarpus campestris (tribe Dalbergieae) possess a mannose biding lectin (LCaL) purified by ion exchange chromatography on DEAE-Sephacel, HiTrap DEAE FF and TSKgel engaged in AKTA-HPLC system. LCaL agglutinates trypsinized rabbit erythrocytes and its activity was maintained after incubation in a wide range of temperature (4-100 °C) and pH (4-9). The lectin had its apparent molecular weight evaluated by size-exclusion chromatography and SDS-PAGE and presented a profile of 10 kDa and 25 kDa in denaturing and native conditions, respectively. LCaL injected by intravenous route in mice showed antinociceptive activity in the behavioral tests of Formalin and Writhing. In the formalin test LCaL inhibited the licking time by 37% in the neurogenic phase and by 73% in the inflammatory phase. In the acetic acid-induced writhing test LCaL showed inhibitory effect at 0.1 mg/kg (72%), 1 mg/kg (74%) and 10 mg/kg (70%). The lectin also inhibited the increase in vascular permeability at 10 mg/kg and leukocyte migration at 0.1, 1 and 10 mg/kg concentrations. Additionally, LCaL inhibited paw edema (mainly from 1 to 3 h by 46%) and hyperalgesia (1 h: 82%; 3 h: 63%) induced by carrageenan. In conclusion, LCaL presents an antinociceptive action mainly via inhibition of inflammation.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Fabaceae/química , Lectinas/isolamento & purificação , Nociceptividade/efeitos dos fármacos , Sementes/química , Animais , Hemaglutinação , Lectinas/química , Masculino , Camundongos , Peso Molecular
15.
Curr Protein Pept Sci ; 20(3): 220-230, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29895242

RESUMO

Lectins are proteins or glycoproteins of non-immune origin which have at least one noncatalytic domain that bind reversibly to specific mono or oligosaccharides. Traditional Chinese Medicine (TCM) involves a broad range of medicinal practices sharing common concepts which have been developed in China and are based on a tradition of more than thousands of years. Plant materials which are commonly used in TCM as a complementary or alternative for Western medical treatments contain a considerable number of important lectins. These lectins have been reported to have various applications and uses such as cancer treatment, glycoconjugate research, biomarker development, and others. Here, we summarize the available literature related to lectins from TCM and recent trends in their potential biomedical applications.


Assuntos
Lectinas , Medicina Tradicional Chinesa , Animais , Glicoproteínas/isolamento & purificação , Glicoproteínas/uso terapêutico , Humanos , Lectinas/isolamento & purificação , Lectinas/uso terapêutico , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico
16.
Protein Expr Purif ; 154: 62-65, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30292806

RESUMO

The gene of mtl from the mussel Mytilus trossulus was cloned into pET-40b(+) expression vector. After expression in E. coli using designed MX-medium an instable soluble form of MTL was obtained. The developed isolation method of the recombinant protein in "semi-denatured" conditions allowed obtaining an active soluble form of the homogenous lectin from the mussel M. trossulus (r-MTL). Both of the lectins had similar antigenic and spatial structures.


Assuntos
Expressão Gênica , Lectinas , Mytilus , Animais , Escherichia coli/química , Escherichia coli/genética , Lectinas/biossíntese , Lectinas/química , Lectinas/genética , Lectinas/isolamento & purificação , Mytilus/química , Mytilus/genética , Coelhos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
17.
Int J Mol Sci ; 20(1)2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30577614

RESUMO

Lectins are a widely studied group of proteins capable of specific and reversible binding to carbohydrates. Undoubtedly, the best characterized are those extracted from plants of the Leguminosae family. Inside this group of proteins, those from the Diocleinae subtribe have attracted attention, in particular Concanavalin A (ConA), the best-studied lectin of the group. Diocleinae lectins, also called ConA-like lectins, present a high similarity of sequence and three-dimensional structure and are known to present inflammatory, vasoactive, antibiotic, immunomodulatory and antitumor activities, among others. This high similarity of lectins inside the ConA-like group makes it possible to use them to study structure/biological activity relationships by the variability of both carbohydrate specificity and biological activities results. It is in this context the following review aims to summarize the most recent data on the biochemical and structural properties, as well as biological activities, of ConA-like lectins and the use of these lectins as models to study structure/biological activity relationships.


Assuntos
Concanavalina A/química , Concanavalina A/farmacologia , Lectinas/química , Lectinas/farmacologia , Carboidratos/química , Fenômenos Químicos , Concanavalina A/genética , Concanavalina A/isolamento & purificação , Mediadores da Inflamação/química , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/farmacologia , Lectinas/genética , Lectinas/isolamento & purificação , Relação Estrutura-Atividade
18.
Glycoconj J ; 35(6): 511-523, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30306293

RESUMO

Plant lectins are gaining interest because of their interesting biological properties. Several Adenia species, that are being used in traditional medicine to treat many health ailments have shown presence of lectins or carbohydrate binding proteins. Here, we report the purification, characterization and biological significance of N-Acetyl galactosamine specific lectin from Adenia hondala (AHL) from Passifloraceae family. AHL was purified in a single step by affinity chromatography on asialofetuin Sepharose 4B column, characterized and its fine sugar specificity determined by glycan array analysis. AHL is human blood group non specific and also agglutinates rabbit erythrocytes. AHL is a glycoprotein with 12.5% of the carbohydrate, SDS-PAGE, MALDI-TOF-MS and ESI-MS analysis showed that AHL is a monomer of 31.6 kDa. AHL is devoid of DNase activity unlike other Ribosome inactivating proteins (RIPs). Glycan array analysis of AHL revealed its highest affinity for terminal lactosamine or polylactosamine of N- glycans, known to be over expressed in hepatocellular carcinoma and colon cancer. AHL showed strong binding to human hepatocellular carcinoma HepG2 cells with MFI of 59.1 expressing these glycans which was effectively blocked by 93.1% by asialofetuin. AHL showed dose and time dependent growth inhibitory effects on HepG2 cells with IC50 of 4.8 µg/ml. AHL can be explored for its clinical potential.


Assuntos
Acetilgalactosamina/metabolismo , Lectinas/isolamento & purificação , Passifloraceae/química , Açúcares/metabolismo , Acetilgalactosamina/química , Animais , Desoxirribonucleases/metabolismo , Haptenos/metabolismo , Hemaglutinação , Células Hep G2 , Humanos , Lectinas/química , Peso Molecular , Monossacarídeos/análise , Raízes de Plantas/química , Polissacarídeos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Suínos
19.
Protein Pept Lett ; 25(9): 871-877, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30182831

RESUMO

BACKGROUND: Marine sponges, belonging to the phylum Porifera, are gaining more attention by researchers and industrial sectors from all over the world due to their ability to produce a variety of bioactive secondary metabolites that have many applications including drug discovery. Marine sponges are a promising source of bioactive lectins, which are structurally diverse, many of them in the form of glycoproteins. OBJECTIVE: To purify and characterize lectin from a marine sponge Fasciospongia cavernosa and to study its antibacterial activity. METHOD: Lectin from a marine sponge Fasciospongia cavernosa was purified by guar gum affinity chromatography and checked for its biophysical and antibacterial properties. The lectin was subjected to evaluation for inhibition of microbial growth against bacteria by aggregation test. The activity of FCL against the biofilms formed by P. aeruginosa was also carried out. Biofilm is defined as the undesirable accumulation of microorganisms on artificial surfaces immersed in a common matrix. The effect of FCL on biofilm-forming gram negative bacteria P. aeruginosa was tested by crystal violet assay. RESULTS: This lectin, named FCL, has a molecular weight of 80 KDa approximately, was found to agglutinate human ABO, rat, rabbit and chicken erythrocytes. The hemagglutinating activity of FCL was reduced by demetallisation with E.D.T.A and regained by the addition of Ca2+, Mg2+, Mn2+, Ba2+ and Fe2+, which shows the metal dependency of the lectin. The hemagglutinating activity by the lectin was inhibited by D-galactose and N-acetyl-D-galactosamine. The lectin was stable over a range of pH from 2 to 10.5, and up to a temperature 70°C for 20 min. FCL agglutinated B. subtilis, S. aureus and P. aeruginosa and was able to reduce biofilm mass formed by P. aeruginosa. Thus, the marine sponge F. cavernosa lectin, FCL could be used as an antibacterial agent. FCL significantly reduced the biomass of bacterial biofilm tested. Biofilm mass of P. aeruginosa, K. pneumoniae and E. coli were decreased in a dose dependent manner. CONCLUSION: A novel lectin was isolated and purified from marine sponge F. cavernosa. FCL, a galactose-binding lectin displayed considerable antimicrobial activity in vitro, particularly against gram-positive bacteria and also exhibited a strong antibiofilm activity.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Lectinas/isolamento & purificação , Lectinas/farmacologia , Poríferos/metabolismo , Acetilgalactosamina/metabolismo , Animais , Biofilmes/efeitos dos fármacos , Galinhas , Cromatografia de Afinidade , Escherichia coli/efeitos dos fármacos , Galactose/metabolismo , Testes de Hemaglutinação , Humanos , Peso Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Coelhos , Ratos , Staphylococcus aureus/efeitos dos fármacos
20.
J Infect ; 77(6): 526-533, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30267797

RESUMO

OBJECTIVES: Interferon-γ release assays (IGRA) are designed for diagnosis of tuberculosis (TB) infection, and do not discriminate latent TB infection (LTBI) from active TB. Heparin-binding hemagglutinin antigen (HBHA) emerged as a promising antigen for TB diagnosis when used in IGRA format. Aim of this study was to prospectively evaluate the performance of an HBHA-based IGRA to support TB diagnosis and TB therapy monitoring in children with TB infection or active TB disease. METHODS: Following clinical, microbiological and radiological assessment, children (0-14 years old) were tested by the QuantiFERON TB-Gold In tube (QFT) assay and an aliquot of whole-blood was stimulated with HBHA and IFNγ evaluated only in QFT-positive subjects. RESULTS: Among the 550 children tested, 486 (88.4%) scored negative and 64 (11.6%) positive. None of the QFT-negative had active TB. Among the QFT-positive, 45 were with LTBI and 19 active TB. HBHA-IGRA scored positive in 41/45 children (91.1%) with LTBI and in 6/19 active TB children (31.6%) at diagnosis (p = 0.001); remarkably, 5 of these 6 children with active TB scoring HBHA-positive were asymptomatic. Moreover, following TB-specific therapy, most of the non-HBHA-responding children, gained an HBHA-positive response. CONCLUSIONS: HBHA-based IGRA is a useful support in TB diagnosis and TB-therapy monitoring in children.


Assuntos
Gerenciamento Clínico , Testes de Liberação de Interferon-gama , Interferon gama/sangue , Tuberculose Latente/diagnóstico , Lectinas/isolamento & purificação , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Itália , Tuberculose Latente/tratamento farmacológico , Masculino , Mycobacterium tuberculosis , Estudos Prospectivos , Teste Tuberculínico
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