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1.
J Helminthol ; 93(1): 57-65, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29248015

RESUMO

The toxicity of water-ethanol extracts of garlic (Allium sativum), ginger (Zingiber officinale), basil (Ocimum basilicum), bitter chaparro (Castela tortuousa), onion (Allium cepa) and papaya (Carica papaya) against adults, eggs and oncomiracidia of Neobenedenia spp. parasites was examined. Parasites were exposed to continuous immersion and treated as follows: extracts were tested at three dilutions: 1:10, 1:50 and 1:100 made with filtered seawater (35 g l-1); ethanol (70%) was evaluated at the same dilutions of 1:10 (7% ethanol), 1:50 (1.4% ethanol) and 1:100 (0.07% ethanol) and a seawater (35 g l-1) control. The antiparasitic effect was measured on: (1) adult survival, egg production and time to detachment from the culture vessel; (2) egg development and cumulative egg hatching; and (3) oncomiracidia survival. All three dilutions of ginger and dilutions 1:100 and 1:50 of basil extract reduced adult survival in vitro, time to detachment from the surface of the culture vessel, egg production and oncomiracidia survival. Bitter chaparro extract reduced adult egg production and oncomiracidia survival. Hatching success was significantly reduced (P < 0.05) in basil extract (1:100) to 86.6% compared to the seawater control (100%). Dilutions 1:10 of ginger and basil exhibited the highest impact on the biological parameters of Neobenedenia sp. Our study demonstrates that water-ethanol extracts of ginger, basil and bitter chaparro are toxic against Neobenedenia sp. life stages.


Assuntos
Ectoparasitoses/veterinária , Doenças dos Peixes/tratamento farmacológico , Helmintíase Animal/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Trematódeos/efeitos dos fármacos , Animais , Antiplatelmínticos/farmacologia , Antiplatelmínticos/uso terapêutico , Ectoparasitoses/tratamento farmacológico , Ectoparasitoses/parasitologia , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Magnoliopsida/química , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Trematódeos/fisiologia
2.
Fish Shellfish Immunol ; 55: 401-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27241285

RESUMO

White spot syndrome virus (WSSV) is the most important viral pathogen for the global shrimp industry causing mass mortalities with huge economic losses. Recombinant phages are capable of expressing foreign peptides on viral coat surface and act as antigenic peptide carriers bearing a phage-displayed vaccine. In this study, the full-length VP28 protein of WSSV, widely known as potential vaccine against infection in shrimp, was successfully cloned and expressed on M13 filamentous phage. The functionality and efficacy of this vaccine immunogen was demonstrated through immunoassay and in vivo challenge studies. In ELISA assay phage-displayed VP28 was bind to Litopenaeus vannamei immobilized hemocyte in contrast to wild-type M13 phage. Shrimps were injected with 2 × 10(10) cfu animal(-1) single dose of VP28-M13 and M13 once and 48 h later intramuscularly challenged with WSSV to test the efficacy of the vaccine against the infection. All dead challenged shrimps were PCR WSSV-positive. The accumulative mortality of the vaccinated and challenged shrimp groups was significantly lower (36.67%) than the unvaccinated group (66.67%). Individual phenoloxidase and superoxide dismutase activity was assayed on 8 and 48 h post-vaccination. No significant difference was found in those immunological parameters among groups at any sampled time evaluated. For the first time, phage display technology was used to express a recombinant vaccine for shrimp. The highest percentage of relative survival in vaccinated shrimp (RPS = 44.99%) suggest that the recombinant phage can be used successfully to display and deliver VP28 for farmed marine crustaceans.


Assuntos
Bacteriófago M13/fisiologia , Penaeidae/imunologia , Penaeidae/virologia , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Vírus da Síndrome da Mancha Branca 1/imunologia , Animais , Hemócitos/imunologia , Hemócitos/virologia , Vacinas Sintéticas/imunologia
3.
Med Vet Entomol ; 25(2): 117-25, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20880281

RESUMO

Oestrus ovis L. (Diptera: Oestridae) is a cosmopolitan agent of myiasis in sheep and goats. The parasitic phase begins after adult females deposit first-stage larvae (L1) into the nostrils of hosts; these larvae develop into L2 and L3 in the nasal and sinus horn cavities. Sneezing and nasal discharges are the major clinical signs in infected animals. The pathogenesis of O. ovis infection is caused by: (a) the trauma resulting from the mechanical action of spines and hooks during larval movement on mucosal membranes, and, more importantly, (b) an allergenic reaction provoked by molecules excreted/secreted by larvae, of which salivary antigens are those mainly recognized by the host's immune system. The recruitment of immune reactive cells increases gradually from the nasal to sinus cavities in infected hosts. Mast cells, eosinophils, macrophages and lymphocytes are always more numerous in infected than non-infected animals. Humoral (antibody) systemic response of immunoglobulin G (IgG) usually reaches seroconversion 2-4 weeks post-first infection and the highest levels are observed during the development of L2 and L3 larvae. Local antibody responses include specific IgG, which has been found to negatively correlate with larval survival and development. Hypersensitivity reaction, immunomodulation, immunization trials and mixed infections of O. ovis and helminths are discussed.


Assuntos
Imunidade Adaptativa , Dípteros/crescimento & desenvolvimento , Doenças das Cabras/imunologia , Miíase/veterinária , Doenças Nasais/veterinária , Doenças dos Ovinos/imunologia , Animais , Dípteros/imunologia , Feminino , Doenças das Cabras/parasitologia , Cabras , Imunidade nas Mucosas , Imunização/veterinária , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Larva/crescimento & desenvolvimento , Larva/imunologia , Miíase/imunologia , Miíase/parasitologia , Miíase/patologia , Infecções por Nematoides/complicações , Infecções por Nematoides/veterinária , Nariz/imunologia , Nariz/parasitologia , Doenças Nasais/imunologia , Doenças Nasais/parasitologia , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
4.
J Appl Microbiol ; 107(6): 1866-74, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19548890

RESUMO

AIMS: To identify and characterize adhesion-associated proteins in the potential probiotic Lactobacillus fermentum BCS87. METHODS AND RESULTS: Protein suspensions obtained from the treatment of Lact. fermentum BCS87 with 1 mol 1(-1) LiCl were analysed by Western blotting using HRP-labelled porcine mucus and mucin. Two adhesion-associated proteins with relative molecular weight of 29 and 32 kDa were identified. The N-terminal and internal peptides of the 32 kDa protein (32-Mmubp) were sequenced, and the corresponding gene (32-mmub) was found by inverse polymerase chain reaction. The complete nucleotide sequence of 32-mmub revealed an open reading frame of 903 bp encoding a primary protein of 300 amino acids and a mature protein of 272 residues. A basic local alignment search showed 47-99% identity to solute-binding components of ATP binding cassette transporter proteins in Lactobacillus, Streptococcus and Clostridium. An OpuAC-conserved domain was identified and phylogenetic relationship analysis confirmed that 32-Mmubp belongs to the OpuAC family. CONCLUSIONS: Adhesion of Lact. fermentum BCS87 appeared to be mediated by two surface-associated proteins. 32-Mmubp is a component of ABC transporter system that also functions as an adhesin. SIGNIFICANCE AND IMPACT OF THE STUDY: Characterization of 32-Mmubp and 32-mmub will contribute to understanding the host-bacteria interactions of Lact. fermentum with the intestinal tract of pigs.


Assuntos
Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Limosilactobacillus fermentum/metabolismo , Probióticos , Transportadores de Cassetes de Ligação de ATP/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Limosilactobacillus fermentum/genética , Dados de Sequência Molecular , Mucinas/metabolismo , Muco/metabolismo , Fases de Leitura Aberta
5.
Vet Parasitol ; 161(3-4): 356-9, 2009 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-19251372

RESUMO

The aims of this study were to analyze the systemic IgG responses against third-instar salivary gland (L3SG) antigens by ELISA in Oestrus ovis experimentally infected kids (EIK) and in naturally exposed adult goats (NEG). Firstly, kids (n=4 per group) were assigned to receive intranasally 0, 12, 24, 36, and 48 first-instars in experimental infections. Blood samples were taken from EIK at Days 0, 14, 42 and 67 post-infection. At necropsy (Day 67), larval number and developmental instars were recorded. In an epidemiological study, blood serum samples were collected from 448 grazing NEG (n=20 flocks) in Baja California Sur, Mexico. Results showed that larval establishment rate was similar in EIK groups. Systemic IgG response reached the threshold after Day 42, but humoral response was not statistically different among EIK groups receiving experimental infections. In NEG, all surveyed flocks (100%) showed specific systemic IgG antibodies to L3SG antigens and the overall goat oestrosis prevalence was 59.2%. In conclusion, larval L3SG antigens were effective in detection of specific systemic IgG antibodies against O. ovis infected kids and goats by ELISA.


Assuntos
Dípteros/imunologia , Doenças das Cabras/parasitologia , Imunoglobulina G/metabolismo , Proteínas de Insetos/imunologia , Animais , Feminino , Doenças das Cabras/imunologia , Cabras , Larva/imunologia , Masculino , Mucosa Nasal/imunologia , Glândulas Salivares/metabolismo
6.
Vet Parasitol ; 155(3-4): 257-63, 2008 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-18584967

RESUMO

Larvae of Oestrus ovis (Diptera: Oestridae) are ubiquitous parasites of nasal and sinusal cavities of sheep and goats. According to the chronobiology of O. ovis infections in Sardinia and the seasonal pattern of the IgG response, the optimal period to investigate the relationships between O. ovis larval populations and intensity of local and systemic IgG antibody responses was mid-July in the summer season. Sarda x Lacaune ewes (n=186), divided into three ram-families were used in the study. Systemic and local IgG responses were measured by ELISA tests using second stage larval crude extracts (L2CE) and L2 (L2SGC) and L3 (L3SGC) salivary gland contents as coating antigens. The number of larval instars, larval length of L1, L2 and L3 larvae, and larval weight of L2 and L3 larvae were individually recorded after ewe necropsy. Negative correlations among larval establishment and/or larval development on the one hand and intensity of local or systemic IgG responses on the other hand were found in two out of three studied ram-families.


Assuntos
Dípteros/crescimento & desenvolvimento , Dípteros/imunologia , Imunoglobulina G/sangue , Doenças Parasitárias em Animais/imunologia , Doenças dos Ovinos/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Itália/epidemiologia , Larva/crescimento & desenvolvimento , Larva/imunologia , Masculino , Doenças Parasitárias em Animais/diagnóstico , Doenças Parasitárias em Animais/epidemiologia , Valor Preditivo dos Testes , Prevalência , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia
7.
Vet Parasitol ; 149(1-2): 117-25, 2007 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-17697751

RESUMO

This study identified and characterized hydrolytic enzymes in salivary gland products of Oestrus ovis larvae. Third instars were collected from the heads of slaughtered goats. Salivary glands were extracted, their products obtained by centrifugation and the enzymatic profile determined. Optimum pH, temperature of maximum proteolytic activity, thermal stability, and resistance of salivary gland products were determined on collagen and subclasses of proteases were identified using protease inhibitors. Zymograms were used to determine the molecular weight of proteases. Antigenic protein bands were revealed by immunoblotting using sera obtained from experimentally infested goats. Seven positive enzymatic activities were detected in salivary gland products: acid phosphatase, naphthol-AS-BI-phosphohydrolase, esterase (C4), esterase lipase (C8), leucine arylamidase, alpha-glucosidase and N-acetyl-beta-glucosaminidase. Optimum pH for proteolytic activity was 8.0; proteolytic activity increased with temperature (10-50 degrees C) then drastically decreased at 60 degrees C. Proteases in O. ovis salivary gland products belong to the serine subclass. In Zymograms, bands of proteolytic activity were detected in the 20-63 kDa range; the immunoblot showed three antigenic bands, one of them related to a protease band (63 kDa). Serine proteases in O. ovis salivary gland products are most likely involved in larval nutrition and host immuno-modulation.


Assuntos
Dípteros/enzimologia , Peptídeo Hidrolases/metabolismo , Proteínas e Peptídeos Salivares/química , Animais , Antígenos/metabolismo , Doenças das Cabras/imunologia , Doenças das Cabras/parasitologia , Cabras , Concentração de Íons de Hidrogênio , Immunoblotting , Larva/efeitos dos fármacos , Larva/enzimologia , Miíase/parasitologia , Miíase/veterinária , Inibidores de Proteases/farmacologia , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/enzimologia , Proteínas e Peptídeos Salivares/isolamento & purificação , Temperatura
8.
J Food Prot ; 80(7): 1090-1098, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28574305

RESUMO

Molds are responsible for postharvest spoilage of citrus fruits. The objective of this study was to evaluate the effect of temperature on growth rate and the time to visible growth of Aspergillus niger strains isolated from citrus fruits. The growth of these strains was studied on agar lime medium (AL) at different temperatures, and growth rate was estimated using the Baranyi and Roberts model (Int. J. Food Microbiol. 23:277-294, 1994). The Rosso et al. cardinal model with inflexion (L. Rosso, J. R. Lobry, S. Bajard, and J. P. Flandrois, J. Theor. Biol. 162:447-463, 1993) was used as a secondary model to describe the effect of temperature on growth rate and the lag phase. We hypothesized that the same model could be used to calculate the time for the mycelium to become visible (tv) by substituting the lag phase (1/λ and 1/λopt) with the time to visible colony (1/tv-opt and 1/tv), respectively, in the Rosso et al. MODEL: High variability was observed at suboptimal conditions. Extremes of temperature of growth for A. niger seem to have a normal variability. For the growth rate and time tv, the model was satisfactorily compared with results of previous studies. An external validation was performed in lime fruits; the bias and accuracy factors were 1.3 and 1.5, respectively, for growth rate and 0.24 and 3.72, respectively, for the appearance time. The discrepancy may be due to the influence of external factors. A. niger grows significantly more slowly on lime fruit than in culture medium, probably because the nutrients are more easily available in medium than in fruits, where the peel consistency may be a physical barrier. These findings will help researchers understand the postharvest behavior of mold on lime fruits, host-pathogen interactions, and environmental conditions infecting fruit and also help them develop guidelines for future work in the field of predictive mycology to improve models for control of postharvest fungi.


Assuntos
Aspergillus niger/crescimento & desenvolvimento , Citrus/microbiologia , Temperatura , Compostos de Cálcio , Óxidos
9.
J Insect Physiol ; 52(8): 861-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16843483

RESUMO

Recent evolutionary studies have suggested that females have a more robust immune system than males. Using two damselfly species (Hetaerina americana and Argia tezpi), we tested if females produced higher immune responses (as phenoloxidase and hydrolytic enzymes), had a higher survival (using a nylon implant inserted in the abdomen and measuring survival after 24h) and fewer parasites (gregarines and water mites) than males. We also tested whether immune differences should emerge in different body areas (thorax vs. abdomen) within each sex with the prediction that only females will differ with the abdomen having a higher immune response than their thorax since the former area, for ecological and physiological reasons, may be a target zone for increased immune investment. Animals were adults of approximately the same age. In both species, females were more immunocompetent than males, but only in H. americana females were immune responses greater in the abdomen than in the thorax. However, there were no differences in survival and parasite intensity or the probability of being parasitised between the sexes in either of the two species. Thus, this study lends partial support to the principle that females are better at defending than males despite the null difference in parasitism and survival.


Assuntos
Insetos/imunologia , Abdome/fisiologia , Animais , Apicomplexa/fisiologia , Tamanho Corporal/imunologia , Feminino , Hidrolases/metabolismo , Proteínas de Insetos/metabolismo , Insetos/enzimologia , Insetos/parasitologia , Masculino , Ácaros/fisiologia , Monofenol Mono-Oxigenase/metabolismo , Fatores Sexuais , Taxa de Sobrevida , Tórax/imunologia
10.
APMIS ; 101(3): 187-93, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7685178

RESUMO

Expression of binding to vitronectin (Vn or S-protein) and fibronectin (Fn) was common among clinical isolates of Candida albicans. Growth at 37 degrees C enhanced expression of both Vn and Fn binding. Some strains expressed higher binding after growth in liquid media and others after growth on solid media. Most strains expressed higher cell surface hydrophobicity after growth on agar media. Vn binding was less influenced by expression of cell surface hydrophobicity than Fn binding. Vn binding to yeast cells was optimal around pH 4 and Fn binding around pH 6. Binding to soluble Vn was inhibited by unlabelled Vn and to a lesser extent by Fn. Fn binding to the same C. albicans strain was inhibited by unlabelled Fn, Vn, fibrinogen and to some extent collagens. C. albicans strain 3248 expressed specific high binding of Vn, and high binding of Fn. Binding of both proteins was sensitive to heat and protease treatment, but in different ways. Vn binding differed significantly from the earlier reported Fn binding and may represent a novel type of tissue adherence.


Assuntos
Candida albicans/citologia , Candida albicans/metabolismo , Fibronectinas/metabolismo , Glicoproteínas/metabolismo , Proteínas Sanguíneas/metabolismo , Candida albicans/fisiologia , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Fibronectinas/análise , Glicoproteínas/análise , Concentração de Íons de Hidrogênio , Ligação Proteica , Vitronectina
11.
APMIS ; 101(9): 695-702, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7694599

RESUMO

A particle agglutination assay (PAA) using fetuin (Ft) covalently coupled to carboxylate-modified latex (CML) particles was evaluated for rapid detection of sialic acid-specific haemagglutinins/lectins (SALs) of Helicobacter pylori isolates which bind sialoglycoconjugates. Sixty-three percent (20/32) of the isolates examined gave a positive PAA test. Cell-bound SALs were extracted by washing the bacteria with deionized water or isotonic saline, and their expression was influenced by pH and culture conditions. The Ft-CML reactivity of the PAA-positive isolates was inhibited by bovine submaxillary mucin, transferrin, fetuin, orosomucoid, vitronectin and lactoferrin in a manner which suggested that the isolates contain a lectin recognizing the alpha(2-6) linkage of terminal sialic acid. Western blots of strain NCTC 11637 SALs probed with horseradish peroxidase (HRP)-labelled Ft identified three bands (MW 64 kD, 62 kD, 56 kD) which also reacted with HRP-labelled mucin, transferrin, lactoferrin, orosomucoid, vitronectin and laminin. Sera from patients with a H. pylori infection and one polyclonal rabbit antiserum (strain NCTC 11637) also reacted with the SALs. Immunogold labelling of a polyclonal rabbit antiserum raised against the 64 kD protein of strain NCTC 11637 that reacted strongly with Ft-CML showed that abundant SALs were loosely cell-associated with the cell surface of both spiral and coccoidal forms of H. pylori. SALs were also present in low amounts on the surface of strain NCTC 11638 and 66, a clinical isolate that did not react with Ft-CML.


Assuntos
Glicoconjugados/análise , Glicoproteínas , Helicobacter pylori/química , Hemaglutininas/análise , Lectinas/análise , Ácidos Siálicos , Animais , Sequência de Carboidratos , Bovinos , Escherichia coli/química , Helicobacter pylori/crescimento & desenvolvimento , Helicobacter pylori/ultraestrutura , Testes de Hemaglutinação , Testes de Fixação do Látex , Dados de Sequência Molecular , Mioglobina , Coelhos/imunologia , Ácidos Siálicos/análise , Staphylococcus aureus/química , alfa-Fetoproteínas
12.
J Med Microbiol ; 47(5): 417-25, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9879942

RESUMO

The gastrointestinal pathogen Aeromonas hydrophila strain A186 produces a collagen-binding protein (CNBP) which is found extracellularly and loosely associated with the cell surface. The cell-associated CNBP was purified by sequential ammonium sulphate precipitation, size-exclusion chromatography and ion-exchange chromatography, or by sequential ammonium sulphate precipitation and affinity chromatography with collagen-Sepharose. The purified CNBP was homogeneous in SDS-PAGE, and had a mol. wt of c. 98 kDa. Cyanogen bromide cleavage of the CNBP destroyed collagen-binding activity; however, enzymic digestion with Staphylococcus aureus V8 protease generated > 10 polypeptide fragments, from which a 30-kDa polypeptide contained the strongest collagen-binding activity. Binding of collagen by the CNBP was restricted to the alpha1 (I) chain of the collagen molecule and binding seemed to involve both the carbohydrate moieties and certain peptide sequences on the collagen. Collagen-saccharides generated by alkaline hydrolysis inhibited collagen binding by A. hydrophila. Also, glycosidase digestion and chemical alteration of the carbohydrate residues of collagen reduced its ability to be bound by the CNBP. Collagen-homologous synthetic peptides inhibited binding of 125I-collagen by the bacteria.


Assuntos
Aeromonas hydrophila/metabolismo , Proteínas de Bactérias/biossíntese , Proteínas de Transporte/biossíntese , Colágeno/metabolismo , Aeromonas hydrophila/patogenicidade , Animais , Anticorpos Antibacterianos , Antígenos de Bactérias/química , Proteínas de Bactérias/química , Proteínas de Bactérias/imunologia , Sítios de Ligação , Proteínas de Transporte/química , Proteínas de Transporte/imunologia , Colágeno/química , Brometo de Cianogênio , Glicosídeo Hidrolases , Humanos , Peso Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Coelhos
13.
J Med Microbiol ; 38(4): 240-4, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7682621

RESUMO

Binding of 125I-heparan sulphate was a common property of Helicobacter pylori strains isolated from patients with gastroduodenal ulcer diseases. Binding was (i) saturable; (ii) reversible by the addition of unlabelled heparan sulphate and heparin; (iii) inhibited by unlabelled heparan sulphate, heparin, and heparin oligosaccharides but not by other glycosaminoglycans of comparable size (chondroitin sulphate and dermatan sulphate) or by highly glycosylated glycoproteins (hog gastric mucin and fetuin); (iv) reduced by heat treatment (80 degrees C, 10 min) and exposure of the bacteria to pronase E, proteinase K, trypsin and chymotrypsin, but unaffected by treatment with pepsin and neuraminidase; and (v) time-, pH-, and ionic strength-dependent. Scatchard plot analysis of the binding data indicated the presence of one class of high-affinity receptor (Kd = 9 x 10(-9) M) for heparan sulphate.


Assuntos
Helicobacter pylori/metabolismo , Heparitina Sulfato/metabolismo , Ligação Competitiva , Dextranos/metabolismo , Endopeptidases/farmacologia , Glicosaminoglicanos/metabolismo , Helicobacter pylori/efeitos dos fármacos , Heparina/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Neuraminidase/farmacologia , Oligossacarídeos/metabolismo , Concentração Osmolar , Fatores de Tempo
14.
J Med Microbiol ; 50(3): 215-222, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11232765

RESUMO

A pool of heparan sulphate-binding proteins (HSBPs) from Helicobacter pylori culture supernates was obtained by sequential ammonium sulphate precipitation and affinity chromatography on heparin-Sepharose. The chromatographic procedure yielded one major fraction that contained proteins with heparan sulphate affinity as revealed by inhibition studies of heparan sulphate binding to H. pylori cells. Preparative iso-electric focusing, SDS-PAGE and blotting experiments, with peroxidase(POD)-labelled heparan sulphate as a probe, indicated the presence of two major extracellular proteins with POD-heparan sulphate affinity. One protein had a molecular mass of 66.2 kDa and a pI of 5.4, whilst the second protein had a molecular mass of 71.5 kDa and a pI of 5.0. The N-terminal amino acid sequence of the 71.5-kDa HSBP did not show homology to any other heparin-binding protein, nor to known proteins of H. pylori, whereas the 66.2-kDa HSBP showed a high homology to an Escherichia coli chaperon protein and equine haemoglobin. A third HSBP was isolated from an outer-membrane protein (OMP) fraction of H. pylori cells with a molecular mass of 47.2 kDa. The amino acid sequence of an internal peptide of the OMP-HSBP did not show homology to the extracellular HSBP of H. pylori, or to another microbial HSBP.


Assuntos
Adesinas Bacterianas/isolamento & purificação , Proteínas de Transporte/isolamento & purificação , Helicobacter pylori/fisiologia , Proteoglicanas de Heparan Sulfato/metabolismo , Adesinas Bacterianas/química , Adesinas Bacterianas/metabolismo , Sequência de Aminoácidos , Proteínas da Membrana Bacteriana Externa/metabolismo , Cromatografia de Afinidade , Focalização Isoelétrica , Peso Molecular
15.
J Med Microbiol ; 49(6): 535-541, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10847207

RESUMO

The presence of Helicobacter pylori in the gastroduodenal mucosae is associated with chronic active gastritis, peptic ulcers and gastric cancers such as adenocarcinoma and low-grade gastric B-cell lymphoma. In response to the presence of antibiotic-resistant strains, the use of vaccines to combat this infection has become an attractive alternative. The present study used a murine model of infection by a mouse-adapted H. pylori strain to determine whether infection in BALB/c mice can be successfully eradicated by intragastric vaccination with H. pylori heparan sulphate-binding proteins (HSBP) covalently coupled to the beta-subunit of cholera toxin (CTB). It was shown that vaccination confers protection against exposure of BALB/c mice to the pathogen, as revealed by microbiological, histopathological and molecular methods.


Assuntos
Vacinas Bacterianas , Fatores de Coagulação Sanguínea , Proteínas de Transporte/imunologia , Toxina da Cólera/imunologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/imunologia , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/administração & dosagem , Bile/imunologia , Proteínas de Transporte/metabolismo , Toxina da Cólera/metabolismo , DNA Bacteriano/análise , Modelos Animais de Doenças , Mucosa Gástrica/imunologia , Mucosa Gástrica/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Heparina/metabolismo , Imunidade nas Mucosas , Imunização/métodos , Imunoglobulina A/análise , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Proteínas de Ligação a RNA , Proteínas Ribossômicas , Vacinas Conjugadas/administração & dosagem
16.
FEMS Immunol Med Microbiol ; 12(3-4): 265-72, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8745013

RESUMO

The pathogenic bacterium Helicobacter pylori, which causes active, chronic type B gastritis and peptic ulcer disease, and increases the risk for development of gastric cancer, could tentatively interfere with growth factors and growth factor receptors of importance for the gastroduodenal mucosa, e.g. heparin-binding FGFs (fibroblast growth factors). H. pylori binds FGF with an extremely strong affinity (3.8 x 10(-12)M), and also heparan sulfate and heparin with higher affinity (Kd 9 x 10(-9)M) than FGFs bind to heparin (10(-8) - 10(-9)M). FGF receptors are also dependent on heparin for their activation. Heparan sulfate binding proteins (HSBP) are exposed on and shed from the surface of H. pylori, which often are localised close to the epithelial stem cells in the gastroduodenal glands. H. pylori could thus efficiently interfere with growth factors and growth factor receptors, tentatively resulting in disturbance of the delicate balance that control the renewal, maintenance and repair of the gastroduodenal mucosa. This mode of action has previously not been considered, but may constitute part of its pathogenic mechanisms. Such a dynamic mode of action of H. pylori may explain the reason for that infected victims may either suffer from gastrointestinal symptoms or lack clinical evidence of disease or discomfort.


Assuntos
Fator 1 de Crescimento de Fibroblastos/metabolismo , Helicobacter pylori/patogenicidade , Heparina/metabolismo , Heparitina Sulfato/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Ligação Proteica
17.
FEMS Immunol Med Microbiol ; 20(3): 219-29, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9566493

RESUMO

Aeromonas species are known to be involved in human gastrointestinal diseases. These organisms colonize the gastrointestinal tract. Aeromonas hydrophila, A. caviae, and A. sobria have been demonstrated microscopically to adhere to animal cell lines that express mucous receptors, but quantitative studies of adherence to mucosal components such as mucin have not been published to date. Purified bovine submaxillary gland, hog gastric mucin, and fish skin mucin were used as a model to study mucin-binding activity among A. caviae, A. hydrophila, and A. sobria strains. Our findings revealed that binding of radiolabeled and enzyme-conjugated mucins to Aeromonas cells varied depending on the labeling procedure. The highest binding was observed when the three mucin preparations were labeled with horseradish peroxidase. Binding of the various horseradish peroxidase-labeled mucins by A. caviae, A. hydrophila, and A. sobria cells is a common property among Aeromonas species isolated from human infections, diseased fish, and from environmental sources. The proportion of Aeromonas strains which bind the various horseradish peroxidase-labeled mucins was significantly higher for A. hydrophila than for A. caviae and A. sobria. Bacterial cell-surface extracts containing active mucin-binding components recognized the horseradish peroxidase-labeled mucins. The molecular masses of the mucin-binding proteins were estimated by SDS-PAGE and Western blot as follows: A. caviae strain A4812 (95 and 44 kDa); A. hydrophila strain 48748 (97, 45, 33 and 22 kDa); and A. sobria strain 48739 (95 and 43 kDa). Mucin interaction with Aeromonas cells was also studied in terms of growth in mucin-rich media. The culture conditions greatly influence the expression of A. hydrophila mucin-binding activity.


Assuntos
Aeromonas hydrophila/metabolismo , Aeromonas/metabolismo , Proteínas de Bactérias/metabolismo , Mucinas/metabolismo , Aeromonas/crescimento & desenvolvimento , Aeromonas hydrophila/crescimento & desenvolvimento , Animais , Aderência Bacteriana , Proteínas de Bactérias/isolamento & purificação , Western Blotting , Bovinos , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Peixes , Mucinas Gástricas/metabolismo , Peroxidase do Rábano Silvestre , Humanos , Immunoblotting , Pele , Glândula Submandibular/metabolismo , Suínos
18.
FEMS Immunol Med Microbiol ; 16(3-4): 163-72, 1996 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-9116633

RESUMO

Western blot analysis (immunoblotting) of cell surface-associated proteins from Helicobacter pylori confirmed our previous findings that binding of human IgG is a common property (among H. pylori strains). Purification of the IgG-binding proteins (IGBP) was achieved by two purification steps, affinity chromatography on IgG-Sepharose and nickel chelate affinity chromatography. SDS-PAGE and immunoblotting analysis revealed a 60 kDa protein with affinity for peroxidase labeled human IgG. Solid phase binding assays showed that IgG binds to an immobilized protein (IGBP). The 60 kDa IGBP binds human IgG1, IgG3 and IgM. Binding could be inhibited by the kappa chain of the human IgG, but not with its Fc fragment, nor with IgA or IgM. In addition, rabbit polyclonal antibodies raised against the 60 kDa IGBP blocked IgG binding. Monoclonal antibodies, specific to the Hsp60 heat shock protein of H. pylori recognized the 60 kDa IGBP as revealed by immunoblotting analysis, both in crude preparations and in the purified fractions.


Assuntos
Proteínas de Bactérias/metabolismo , Chaperonina 60/metabolismo , Helicobacter pylori/metabolismo , Imunoglobulina G/metabolismo , Proteínas de Membrana/metabolismo , Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Proteínas de Bactérias/imunologia , Chaperonina 60/imunologia , Reações Cruzadas , Helicobacter pylori/imunologia , Humanos , Fragmentos Fc das Imunoglobulinas/metabolismo , Isotipos de Imunoglobulinas/metabolismo , Cadeias kappa de Imunoglobulina/metabolismo , Proteínas de Membrana/imunologia , Ligação Proteica
19.
FEMS Immunol Med Microbiol ; 16(3-4): 247-55, 1996 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-9116643

RESUMO

Bovine lactoferrin binds to a 60 kDa heat shock protein of Helicobacter pylori. Binding ability was related to human immunoglobulin G because bovine lactoferrin binding proteins were isolated by extraction of cell surface associated proteins with distilled water, applied on IgG-Sepharose and nickel sulphate chelate affinity chromatography. Binding was demonstrated by Western blot after purified protein was digested with alpha-chymotrypsin and incubated with peroxidase-labeled bovine lactoferrin. Binding was inhibited by bovine lactoferrin, lactose, rhamnose, galactose, and two iron-containing proteins, ferritin and haptoglobin. Helicobacter pylori binds ferritin and haptoglobin via charge or hydrophobic interactions because this binding was not inhibited by specific and various glycoproteins or carbohydrates. Carbohydrate moieties of bovine lactoferrin molecules seem to be involved in binding because glycoproteins with similar carbohydrate structures strongly inhibited binding. Scatchard plot analysis of the binding of peroxidase-labeled bovine lactoferrin to H. pylori cells yielded a kd 2.88 x 10(-6) M. In addition, binding of H. pylori cells to bovine lactoferrin was enhanced when bacteria treated with pepsin or alpha-chymotrypsin after isolation from iron-restricted and iron-containing media.


Assuntos
Antibacterianos/metabolismo , Chaperonina 60/metabolismo , Helicobacter pylori/metabolismo , Lactoferrina/metabolismo , Animais , Sítios de Ligação , Ligação Competitiva , Bovinos , Chaperonina 60/efeitos dos fármacos , Endopeptidases/farmacologia , Humanos , Cinética , Ligação Proteica
20.
Folia Microbiol (Praha) ; 49(1): 64-70, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15114868

RESUMO

The effect of cyanobacterial polysaccharides (from Cyanothece spp. and Cyanospira capsulata) on the binding of Helicobacter pylori to gastric epithelial cells was evaluated. The antiadhesive action on Kato III and HeLa S3 human gastric cell lines was established.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Cianobactérias/metabolismo , Células Epiteliais/microbiologia , Mucosa Gástrica/microbiologia , Helicobacter pylori/fisiologia , Polissacarídeos Bacterianos/farmacologia , Linhagem Celular Tumoral , Células HeLa , Humanos , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/química
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