Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
J Invertebr Pathol ; 171: 107341, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32057750

RESUMEN

Phenoloxidase (PO) is a key enzyme in the melanization process involved in elimination of pathogens in insects. The PO system is rapidly activated in response to pathogen recognition. Inhibition of PO activity can be a way to avoid immune response and increase infection effectiveness. In this study, the effects of inoculation of Galleria mellonella larvae with Aspergillus niger α-1,3-glucan and conidia on PO activity in hemolymph are analyzed in comparison with the effects of ß-1,3/1,6-glucan inoculation. Our results indicate that α-1,3-glucan, a fungal cell wall polysaccharide, can play a role of a virulence factor involved in inhibition of the insect PO system.


Asunto(s)
Aspergillus niger/fisiología , Glucanos/fisiología , Proteínas de Insectos/antagonistas & inhibidores , Monofenol Monooxigenasa/antagonistas & inhibidores , Mariposas Nocturnas/microbiología , Factores de Virulencia/fisiología , Animales , Larva/crecimiento & desarrollo , Larva/microbiología , Mariposas Nocturnas/crecimiento & desarrollo , Esporas Fúngicas/fisiología
2.
Int J Mol Sci ; 21(2)2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31963214

RESUMEN

The mechanisms of action of the complex including entomopathogenic nematodes of the genera Steinernema and Heterorhabditis and their mutualistic partners, i.e., bacteria Xenorhabdus and Photorhabdus, have been well explained, and the nematodes have been commercialized as biological control agents against many soil insect pests. However, little is known regarding the nature of the relationships between these bacteria and the gut microbiota of infected insects. In the present study, 900 bacterial isolates that were obtained from the midgut samples of Melolontha melolontha larvae were screened for their antagonistic activity against the selected species of the genera Xenorhabdus and Photorhabdus. Twelve strains exhibited significant antibacterial activity in the applied tests. They were identified based on 16S rRNA and rpoB, rpoD, or recA gene sequences as Pseudomonas chlororaphis, Citrobacter murliniae, Acinetobacter calcoaceticus, Chryseobacterium lathyri, Chryseobacterium sp., Serratia liquefaciens, and Serratia sp. The culture filtrate of the isolate P. chlororaphis MMC3 L3 04 exerted the strongest inhibitory effect on the tested bacteria. The results of the preliminary study that are presented here, which focused on interactions between the insect gut microbiota and mutualistic bacteria of entomopathogenic nematodes, show that bacteria inhabiting the gut of insects might play a key role in insect resistance to entomopathogenic nematode pressure.


Asunto(s)
Larva/microbiología , Photorhabdus/genética , Photorhabdus/aislamiento & purificación , Xenorhabdus/genética , Xenorhabdus/aislamiento & purificación , Acinetobacter calcoaceticus/genética , Acinetobacter calcoaceticus/aislamiento & purificación , Animales , Chryseobacterium/genética , Chryseobacterium/aislamiento & purificación , Citrobacter/genética , Citrobacter/aislamiento & purificación , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiología , Pseudomonas chlororaphis/genética , Pseudomonas chlororaphis/aislamiento & purificación , ARN Ribosómico 16S/genética , Serratia liquefaciens/genética , Serratia liquefaciens/aislamiento & purificación , Simbiosis/genética , Simbiosis/fisiología
3.
Int J Mol Sci ; 21(11)2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32471277

RESUMEN

Fourier transform infrared (FT-IR) and Raman spectroscopy and mapping were applied to the analysis of biofilms produced by bacteria of the genus Streptococcus. Bacterial biofilm, also called dental plaque, is the main cause of periodontal disease and tooth decay. It consists of a complex microbial community embedded in an extracellular matrix composed of highly hydrated extracellular polymeric substances and is a combination of salivary and bacterial proteins, lipids, polysaccharides, nucleic acids, and inorganic ions. This study confirms the value of Raman and FT-IR spectroscopies in biology, medicine, and pharmacy as effective tools for bacterial product characterization.


Asunto(s)
Biopelículas , Caries Dental/microbiología , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectrometría Raman/métodos , Streptococcus/patogenicidad , Proteínas Bacterianas/química , Matriz Extracelular/química , Humanos , Polisacáridos Bacterianos/química , Saliva/química , Saliva/microbiología , Streptococcus/metabolismo
4.
Molecules ; 25(23)2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-33255915

RESUMEN

Increasing knowledge of the role of the intestinal microbiome in human health and well-being has resulted in increased interest in prebiotics, mainly oligosaccharides of various origins. To date, there are no reports in the literature on the prebiotic properties of oligosaccharides produced by the hydrolysis of pure fungal α-(1→3)-glucan. The aim of this study was to prepare α-(1→3)-glucooligosaccharides (α-(1→3)-GOS) and to perform initial evaluation of their prebiotic potential. The oligosaccharides were obtained by acid hydrolysis of α-(1→3)-glucan isolated from the fruiting bodies of Laetiporus sulphureus and then, characterized by HPLC. Fermentation of α-(1→3)-GOS and reference prebiotics was compared in in vitro pure cultures of Lactobacillus, Bifidobacterium, and enteric bacterial strains. A mixture of α-(1→3)-GOS, notably with a degree of polymerization of 2 to 9, was obtained. The hydrolysate was utilized for growth by most of the Lactobacillus strains tested and showed a strong bifidogenic effect, but did not promote the growth of Escherichia coli and Enterococcus faecalis. α-(1→3)-GOS proved to be effective in the selective stimulation of beneficial bacteria and can be further tested to determine their prebiotic functionality.


Asunto(s)
Polisacáridos Fúngicos/química , Glucanos/química , Oligosacáridos/química , Polyporales/química , Prebióticos , Cromatografía Líquida de Alta Presión , Humanos , Hidrólisis
5.
Molecules ; 24(21)2019 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-31684030

RESUMEN

The cell walls of fungi are composed of glycoproteins, chitin, and α- and ß-glucans. Although there are many reports on ß-glucans, α-glucan polysaccharides are not yet fully understood. This review characterizes the physicochemical properties and functions of (1→3)-α-d-glucans. Particular attention has been paid to practical application and the effect of glucans in various respects, taking into account unfavourable effects and potential use. The role of α-glucans in plant infection has been proven, and collected facts have confirmed the characteristics of Aspergillus fumigatus infection associated with the presence of glucan in fungal cell wall. Like ß-glucans, there are now evidence that α-glucans can also stimulate the immune system. Moreover, α-d-glucans have the ability to induce mutanases and can thus decompose plaque.


Asunto(s)
Aspergilosis/microbiología , Pared Celular/química , Glucanos/química , Enfermedades de las Plantas/microbiología , Aspergillus fumigatus/química , Aspergillus fumigatus/patogenicidad , Quitina/química , Hongos/química , Glicoproteínas/química , Polisacáridos/química , beta-Glucanos/química
6.
Biotechnol Appl Biochem ; 64(3): 337-346, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-26969579

RESUMEN

Biofilm-related infections of the oral cavity, including dental caries and periodontitis, represent the most prevalent health problems. For years, the treatment thereof was largely based on antibacterial chemical agents. Recently, however, there has been growing interest in the application of more preventive and minimally invasive biotechnological methods. This review focuses on the potential applications of enzymes in the treatment and prevention of oral diseases. Dental plaque is a microbial community that develops on the tooth surface, embedded in a matrix of extracellular polymeric substances of bacterial and host origin. Both cariogenic microorganisms and the key components of oral biofilm matrix may be the targets of the enzymes. Oxidative salivary enzymes inhibit or limit the growth of oral pathogens, thereby supporting the natural host defense system; polysaccharide hydrolases (mutanases and dextranases) degrade important carbohydrate components of the biofilm matrix, whereas proteases disrupt bacterial adhesion to oral surfaces or affect cell-cell interactions. The efficiency of the enzymes in in vitro and in vivo studies, advantages and limitations, as well as future perspectives for improving the enzymatic strategy are discussed.


Asunto(s)
Antibacterianos/uso terapéutico , Bacterias/crecimiento & desarrollo , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Dextranasa/uso terapéutico , Glicósido Hidrolasas/uso terapéutico , Periodontitis , Placa Dental/tratamiento farmacológico , Placa Dental/microbiología , Humanos , Periodontitis/tratamiento farmacológico , Periodontitis/microbiología
7.
World J Microbiol Biotechnol ; 33(5): 83, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28378220

RESUMEN

Higher Basidiomycota have been used in natural medicine throughout the world for centuries. One of such fungi is Fomitopsis betulina (formerly Piptoporus betulinus), which causes brown rot of birch wood. Annual white to brownish fruiting bodies of the species can be found on trees in the northern hemisphere but F. betulina can also be cultured as a mycelium and fruiting body. The fungus has a long tradition of being applied in folk medicine as an antimicrobial, anticancer, and anti-inflammatory agent. Probably due to the curative properties, pieces of its fruiting body were carried by Ötzi the Iceman. Modern research confirms the health-promoting benefits of F. betulina. Pharmacological studies have provided evidence supporting the antibacterial, anti-parasitic, antiviral, anti-inflammatory, anticancer, neuroprotective, and immunomodulating activities of F. betulina preparations. Biologically active compounds such as triterpenoids have been isolated. The mushroom is also a reservoir of valuable enzymes and other substances such as cell wall (1→3)-α-D-glucan which can be used for induction of microbial enzymes degrading cariogenic dental biofilm. In conclusion, F. betulina can be considered as a promising source for the development of new products for healthcare and other biotechnological uses.


Asunto(s)
Coriolaceae/química , Cuerpos Fructíferos de los Hongos/química , Biotecnología , Industria Farmacéutica , Medicina Tradicional , Terpenos/aislamiento & purificación , Terpenos/farmacología
8.
World J Microbiol Biotechnol ; 32(9): 151, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27465851

RESUMEN

Piptoporus betulinus is a wood-rotting basidiomycete used in medicine and biotechnology. However, to date, no indoor method for cultivation of this mushroom fruiting bodies has been developed. Here we present the first report of successful production of P. betulinus mature fruiting bodies in artificial conditions. Four P. betulinus strains were isolated from natural habitats and their mycelia were inoculated into birch sawdust substrate supplemented with organic additives. All the strains effectively colonized the medium but only one of them produced fruiting bodies. Moisture and organic supplementation of the substrate significantly determined the fruiting process. The biological efficiency of the P. betulinus PB01 strain cultivated on optimal substrate (moisture and organic substance content of 55 and 65 and 25 or 35 %, respectively) ranged from 12 to 16 %. The mature fruiting bodies reached weight in the range from 50 to 120 g. Anticancer properties of water and ethanol extracts isolated from both cultured and nature-derived fruiting bodies of P. betulinus were examined in human colon adenocarcinoma, human lung carcinoma and human breast cancer cell lines. The studies revealed antiproliferative and antimigrative properties of all the investigated extracts. Nevertheless the most pronounced effects demonstrated the ethanol extracts, obtained from fruiting bodies of cultured P. betulinus. Summarizing, our studies proved that P. betulinus can be induced to fruit in indoor artificial culture and the cultured fruiting bodies can be used as a source of potential anticancer agents. In this respect, they are at least as valuable as those sourced from nature.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Coriolaceae/crecimiento & desarrollo , Cuerpos Fructíferos de los Hongos/química , Células A549 , Betula/microbiología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Coriolaceae/química , Etanol/farmacología , Células HT29 , Humanos , Micelio/química
9.
Molecules ; 18(8): 9117-31, 2013 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-23903184

RESUMEN

In this study, for the first time, we investigated in vitro inhibitory effects of Drymocallis rupestris extracts and their subfractions obtained with solvents of different polarity (aqueous, 50% ethanolic, diethyl ether, ethyl acetate and n-butanolic) against bacterial viability and caries virulence factors of Streptococcus spp. strains. The diethyl ether subfraction (PRU2) showed bacteriostatic and bactericidal activity against mutans streptococci, with minimum inhibitory concentrations (MICs) in the range of 0.75-1.5 mg/mL and minimum bactericidal concentrations (MBCs) in the range of 1.5-3 mg/mL. Furthermore, PRU2 inhibited biofilm formation by Streptococci in a dose-dependent manner. It was also found that all five D. rupestris preparations exhibited diverse inhibitory effects on de novo synthesis of water-insoluble and water-soluble α-D-glucans by glucosyltransferases of the mutans group streptococci. The phytochemical profile of investigated samples was determined by spectrophotometric and chromatographic (HPLC-DAD-MS³) methods. The high polyphenol (total phenol, phenolic acids, tannins, proantocyanidins, and flavonoids) contents were found which correlated with anticariogenic activity of the analyzed samples. The results demonstrate that D. rupestris extracts and their subfractions could become useful supplements for pharmaceutical products as a new anticariogenic agent in a wide range of oral care products. Further studies are necessary to clarify which phytoconstituents of D. rupestris are responsible for anticaries properties.


Asunto(s)
Cariogénicos/farmacología , Caries Dental/microbiología , Viabilidad Microbiana/efectos de los fármacos , Extractos Vegetales/farmacología , Rosaceae/química , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Cariogénicos/química , Cromatografía Líquida de Alta Presión , Caries Dental/tratamiento farmacológico , Humanos , Técnicas In Vitro , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Polifenoles/química , Streptococcus/efectos de los fármacos , Streptococcus/patogenicidad , Taninos/química
10.
World J Microbiol Biotechnol ; 29(4): 753-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23229287

RESUMEN

Laetiporus sulphureus is an edible wood-rotting basidiomycete fungus whose fruiting bodies contain substances with verified therapeutic evidences and large amounts of α-(1 → 3)-glucan which is used as an effective inducer of microbial α-(1 → 3)-glucanases. However, production of mature fruiting bodies of this species under artificially controlled conditions has not been reported until now. Here, we provide the first report of successful initiation and development of L. sulphureus fruiting bodies in large-scale experiments. Twelve Laetiporus strains were isolated from a natural habitat. A synthetic log production system with a substrate composed of a mixture of sawdust enriched with organic and inorganic additives was developed. It was found that shocking the fungus mycelium with cold water or low temperature was the only suitable method for forced fruiting of L. sulphureus strains. Primordia of two strains were initiated already after 5-6 days from induction, and after another 2 days, they began to develop into fruiting bodies. Carpophores appeared fastest on substrates with high organic supplementation (40-45 %) and a low moisture content (40 %). The resulting mature fruiting bodies reached a weight of 200-300 g. The method of cultivation presented in this paper opens the way to commercial production of this valuable basidiomycete.


Asunto(s)
Coriolaceae/crecimiento & desarrollo , Medios de Cultivo/química , Cuerpos Fructíferos de los Hongos/crecimiento & desarrollo , Frío , Coriolaceae/clasificación , Coriolaceae/aislamiento & purificación , Coriolaceae/efectos de la radiación , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Cuerpos Fructíferos de los Hongos/efectos de la radiación , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
11.
Acta Pol Pharm ; 70(3): 523-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23757943

RESUMEN

Potentilla L. (Rosaceae) species have been used in traditional medicine in Asia, Europe and Northern America. This study analyzed the biological activity of aqueous extracts of Potentilla species (Rosaceae): Dasiphora fruticosa (syn. P. fruticosa), P. norvegica, P. pensylvanica, P. thuringiaca, P. crantzii and P. nepalensis. The activities were tested using MTT, NR and DPPH assays on normal human colon epithelium (CCD 841 CoTr) and colon myofibroblast (CCD-18Co) cells. Moreover, cell morphology using the May-Grünwald-Giemsa method, IL-6 by ELISA, and nitric oxide (NO) analysis with the Griess method in culture supernatants were performed after 24 h. Extracts were tested at dose levels between 25 and 250 microg/mL. For ELISA, 15 microg/mL was chosen. All extracts suppressed the metabolism of myofibroblasts, while epithelial cells' mitochondrial dehydrogenase activity decreased after incubation with extracts. All extracts showed a free radical scavenging (DPPH) effect in a concentration-dependent manner. The most potent was the extract from D. fruticosa, while the least action was observed for P. thuringiaca. Potentilla extracts stimulated, IL-6 production in tested cells but the level of the cytokine was found to decrease in epithelial cells. Pre-incubation of cells with LPS resulted in increased IL-6 secretion. Modulation of NO production after extract addition and cell pre-incubation with LPS was also observed. Potentilla extracts may be interesting natural factors modulating the main features of cells forming the colon wall, and thus may be potentially useful in the prophylaxis or healing of colon disorders.


Asunto(s)
Colon/efectos de los fármacos , Extractos Vegetales/farmacología , Potentilla , Células Cultivadas , Colon/metabolismo , Humanos , Interleucina-6/biosíntesis , Lipopolisacáridos/farmacología , Óxido Nítrico/biosíntesis , Extractos Vegetales/análisis , Polifenoles/análisis , Potentilla/química
12.
Protein Expr Purif ; 86(1): 68-74, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22982219

RESUMEN

Mutanases hydrolyze d-glucosidic linkages of α-1,3-linked polysaccharides which are important components of dental plaque. Therefore, these enzymes can be useful in preventive oral hygiene. A gene encoding mutanase was cloned from soil-isolated Paenibacillus curdlanolyticus MP-1 and expressed in Escherichia coli, and the resulting recombinant enzyme was characterized. The nucleotide sequence of the mutanase gene consisted of 3786 nucleotides encoding a protein of 1261 amino acids with a theoretical molecular weight of 131.62kDa. The deduced amino acid sequence exhibited a high degree of similarity with mutanases of Paenibacillus sp. KSM-M126 and Paenibacillus humicus NA1123, with 84% and 80% identity, respectively. The recombinant enzyme was purified 17.5-fold to homogeneity with a recovery of 37%. The purified mutanase showed optimal activity at pH 6.0 and 45°C, and was completely stable at pH 4.0-9.5 and up to 45°C. The enzyme was specific for α-1,3-glucosidic linkages and effectively solubilized fungal α-1,3-glucans and streptococcal mutans, releasing nigerooligosaccharides. The mutanase did not hydrolyze a synthetic substrate readily hydrolyzed by exoglucanases and the enzyme activity was not suppressed in the presence of deoxynojirimycin, an inhibitor of exo-type enzymes. These results suggest an endohydrolytic mode of action.


Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Glicósido Hidrolasas/aislamiento & purificación , Paenibacillus/enzimología , Secuencia de Aminoácidos , Aspergillus niger/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Clonación Molecular , ADN Bacteriano/genética , Activación Enzimática , Pruebas de Enzimas , Estabilidad de Enzimas , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Genes Bacterianos , Vectores Genéticos/genética , Glucanos/metabolismo , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Concentración de Iones de Hidrógeno , Hidrólisis , Datos de Secuencia Molecular , Peso Molecular , Paenibacillus/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Streptococcus/metabolismo , Especificidad por Sustrato
13.
Int J Mol Sci ; 13(8): 9584-9598, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22949817

RESUMEN

Mutanase (α-(1→3)-glucanase) is a little-known inductive enzyme that is potentially useful in dentistry. Here, it was shown that the cell wall preparation (CWP) obtained from the fruiting body or vegetative mycelium of polypore fungus Laetiporus sulphureus is rich in α-(1→3)-glucan and can be successfully used for mutanase induction in Trichoderma harzianum. The content of this biopolymer in the CWP depended on the age of fruiting bodies and increased along with their maturation. In the case of CWP prepared from vegetative mycelia, the amount of α-(1→3)-glucan depended on the mycelium age and also on the kind of medium used for its cultivation. All CWPs prepared from the individually harvested fruiting body specimens induced high mutanase activity (0.53-0.82 U/mL) in T. harzianum after 3 days of cultivation. As for the CWPs obtained from the hyphal mycelia of L. sulpureus, the maximal enzyme productivity (0.34 U/mL after 3 days of incubation) was recorded for CWP prepared from the 3 week-old mycelium cultivated in Sabouraud medium. Statistically, a high positive correlation was found between the total percentage content of α-(1→3)-glucan in the CWP and the mutanase activity.


Asunto(s)
Coriolaceae/metabolismo , Cuerpos Fructíferos de los Hongos/metabolismo , Glucanos/metabolismo , Glicósido Hidrolasas/metabolismo , Micelio/metabolismo , Trichoderma/enzimología , Pared Celular/metabolismo , Coriolaceae/crecimiento & desarrollo , Inducción Enzimática , Técnica del Anticuerpo Fluorescente , Cuerpos Fructíferos de los Hongos/crecimiento & desarrollo , Micelio/crecimiento & desarrollo , Trichoderma/genética
14.
Prep Biochem Biotechnol ; 42(4): 335-47, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22708811

RESUMEN

Mutanases are enzymes that catalyze hydrolysis of α-1,3-glucosidic bonds in various α-glucans. One of such glucans, mutan, which is synthesized by cariogenic streptococci, is a major virulence factor for induction of dental caries. This means that mutan-degrading enzymes have potential in caries prophylaxis. In this study, we report the purification, characterization, and partial amino acid sequence of extracellular mutanase produced by the MP-1 strain of Paenibacillus curdlanolyticus, bacterium isolated from soil. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of the purified enzyme showed a single protein band of molecular mass 134 kD, while native gel filtration chromatography confirmed that the enzyme was a monomer of 142 kD. Mutanase showed a pH optimum in the range from pH 5.5 to 6.5 and a temperature optimum around 40-45°C. It was thermostable up to 45°C, and retained 50% activity after 1 hr at 50°C. The enzyme was fully stable at a pH range of 4 to 10. The enzyme activity was stimulated by the addition of Tween 20, Tween 80, and Ca²âº, but it was significantly inhibited by Hg²âº, Ag⁺, and Fe²âº, and also by p-chloromercuribenzoate, iodoacetamide, and ethylenediamine tetraacetic acid (EDTA). Mutanase preparation preferentially catalyzed the hydrolysis of various streptococcal mutans and fungal α-1,3-glucans. It also showed binding activity to insoluble α-1,3-glucans. The N-terminal amino acid sequence was NH2-Ala-Gly-Gly-Thr-Asn-Leu-Ala-Leu-Gly-Lys-Asn-Val-Thr-Ala-Ser-Gly-Gln. This sequence indicated an analogy of the enzyme to α-1,3-glucanases from other Paenibacillus and Bacillus species.


Asunto(s)
Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Paenibacillus/enzimología , Secuencia de Aminoácidos , Estabilidad de Enzimas , Glicósido Hidrolasas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Paenibacillus/química , Alineación de Secuencia , Especificidad por Sustrato , Temperatura
15.
Molecules ; 17(10): 11800-15, 2012 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-23047481

RESUMEN

Streptococcal mutans synthesized under different conditions by growing cultures or by their glucosyltransferases were shown to exhibit a great structural and property diversity. Culturing and environmental factors causing structural differences in mutans were specified. All of the obtained biopolymers (76 samples) were water-insoluble and most of them (72) had a structure with a predominance of α-(1→3)-linked glucose (i.e., the content of α-(1→3)-linkages in the glucan was always higher than 50%, but did not exceed 76%). An exception were four glucans containing more than 50% of α-(1→6)-sequences. In these structurally unique mutans, the ratio of α-(1→3)- to α-(1→6)-bonds ranged from 0.75 to 0.97. Aside from one polymer, all others had a heavily branched structures and differed in the number of α-(1→3), α-(1→6), and α-(1→3,6) linkages and their mutual proportion. The induction of mutanase production in shaken flask cultures of Trichoderma harzianum by the structurally diverse mutans resulted in enzyme activities ranging from 0.144 to 1.051 U/mL. No statistical correlation was found between the total percentage content of α-(1→3)-linkages in the α-glucan and mutanase activity. Thus, despite biosynthetic differences causing structural variation in the mutans, it did not matter which mutan structures were used to induce mutanase production.


Asunto(s)
Glicósido Hidrolasas/biosíntesis , Glicósido Hidrolasas/química , Streptococcus mutans/enzimología , Medios de Cultivo , Activación Enzimática , Concentración de Iones de Hidrógeno , Resonancia Magnética Nuclear Biomolecular , Streptococcus mutans/crecimiento & desarrollo , Temperatura
16.
Phytother Res ; 25(3): 343-50, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20677176

RESUMEN

This study, for the first time, investigated the in vitro inhibitory effects of Potentilla recta extracts and subfractions obtained with solvents of different polarity (aqueous, 50% ethanol, diethyl ether, ethyl acetate and n-butanol) against cariogenic Streptococcus spp. strains. It was found that the tested samples inhibited the growth of oral streptococci. Furthermore, all five P. recta preparations exhibited an inhibitory effect on water-insoluble α-(1→3)-,α-(1→6)-linked glucan (mutan) and artificial dental plaque formation. The ethyl acetate fraction showed the highest antibiofilm activities especially against S. sobrinus GCM 20381, with minimum mutan and biofilm inhibition concentrations of 6.25 and 25 µg/mL, respectively. The phytochemical profile of active constituents in the investigated samples was analysed. The high polyphenolics (total phenol, phenolic acids, tannins, proantocyanidins, flavonoids) content were found. The ethyl acetate fraction showed the highest concentration of total polyphenol content which may correlate with the high cariogenic activity of this subfraction. The results demonstrate that P. recta extracts and subfractions could become useful supplements for pharmaceutical products as new anticariogenic agents in a wide range of oral care products. Further studies are necessary to clarify the precise bioactive constituents of P. recta responsible for the anticariogenic properties.


Asunto(s)
Antibacterianos/farmacología , Cariostáticos/farmacología , Extractos Vegetales/farmacología , Potentilla/química , Streptococcus sobrinus/efectos de los fármacos , Biopelículas/efectos de los fármacos , Placa Dental/prevención & control , Flavonoides/análisis , Pruebas de Sensibilidad Microbiana , Fenoles/análisis , Componentes Aéreos de las Plantas/química , Polifenoles , Proantocianidinas/análisis , Taninos/análisis
17.
Pol J Microbiol ; 60(4): 293-301, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22390063

RESUMEN

alpha-1,3-Glucanases (mutanases) are currently of great interest due to their potential use in the field of dental care. These enzymes have been reported in several bacteria, yeasts and fungi, but up to now, characterization of this family of proteins has been relatively poor. In this study, we identify and characterize a mutanase gene from Trichoderma harzianum CCM F-340. Sequence analysis, on the nucleotide and amino acid levels reveals that this alpha-1,3-glucanase is highly homologous to alpha-1,3-glucanases from T harzianum isolate CBS 243.71 and T asperellum CECT 20539. T. harzianum CCM F-340 mutanase is a 634-aa residue protein with a calculated molecular mass of 67.65 kDa, composed of two distinct, highly conserved domains (a long N-terminal catalytic domain and a short C-terminal polysaccharide-binding domain) separated by a less conserved Pro-Ser-Thr-rich linker region. The mutanase gene was expressed in an E. coli BL21 (DE3) host, under the transcriptional control of T7 promoter. The purified enzyme migrated as a band of about 68 kDa after SDS-polyacrylamide gel electrophoresis, which coincided with the predicted size based on the amino acid sequence. Our data indicate that this enzyme is highly conserved in Trichoderma and can be produced in active form in such heterologous expression system.


Asunto(s)
Glicósido Hidrolasas/genética , Streptococcus/metabolismo , Trichoderma/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Activación Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Glicósido Hidrolasas/aislamiento & purificación , Glicósido Hidrolasas/metabolismo , Hidrólisis , Datos de Secuencia Molecular , Filogenia , Plásmidos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Trichoderma/clasificación , Trichoderma/enzimología
18.
Molecules ; 15(7): 4639-51, 2010 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-20657382

RESUMEN

The aerial parts of selected Potentilla species (P. anserina, P. argentea, P. erecta, P. fruticosa, P. grandiflora, P. nepalensis, P. norvegica, P. pensylvanica, P. crantzii and P. thuringiaca) were investigated in order to determine their contents of polyphenolic compounds. The results showed that P. fruticosa has relatively high concentrations of tannins (167.3 +/- 2.0 mg/g dw), proanthocyanidins (4.6 +/- 0.2 mg/g dw) and phenolic acids (16.4 +/- 0.8 mg/g dw), as well as flavonoids (7.0 +/- 1.1 mg/g dw), calculated as quercetin. Furthermore, we investigated the in vitro inhibitory effects of aqueous extracts from these species against cariogenic Streptococcus spp. strains. It was found that the tested samples moderately inhibit the growth of oral streptococci. However, all the preparations exhibited inhibitory effects on water-insoluble alpha-(1-->3)-, alpha-(1-->6)-linked glucan (mutan) and artificial dental plaque formation. The extract from P. fruticosa showed the highest anti-biofilm activities, with minimum mutan and biofilm inhibition concentrations of 6.25-25 and 50-100 microg/mL, respectively. The results indicate that the studied Potentilla species could be a potential plant material for extracting biologically active compounds, and could become a useful supplement for pharmaceutical products as a new anticariogenic agent in a wide range of oral care products.


Asunto(s)
Antibacterianos/farmacología , Placa Dental/tratamiento farmacológico , Flavonoides/análisis , Fenoles/análisis , Potentilla/química , Antibacterianos/aislamiento & purificación , Biopelículas/efectos de los fármacos , Atención Odontológica , Higiene Bucal , Componentes Aéreos de las Plantas/química , Polifenoles , Streptococcus/efectos de los fármacos
19.
Pathog Dis ; 78(9)2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33232457

RESUMEN

Alpha-1,3-glucan, in addition to ß-1,3-glucan, is an important polysaccharide component of fungal cell walls. It is reported for many fungal species, including human pathogenic genera: Aspergillus, Blastomyces, Coccidioides, Cryptococcus, Histoplasma and Pneumocystis, plant pathogens, e.g. Magnaporthe oryzae and entomopathogens, e.g. Metarhizium acridum. In human and plant pathogenic fungi, α-1,3-glucan is considered as a shield for the ß-1,3-glucan layer preventing recognition of the pathogen by the host. However, its role in induction of immune response is not clear. In the present study, the cellular immune response of the greater wax moth Galleria mellonella to Aspergillus niger α-1,3-glucan was investigated for the first time. The changes detected in the total hemocyte count (THC) and differential hemocyte count (DHC), formation of hemocyte aggregates and changes in apolipophorin III localization indicated activation of G. mellonella cellular mechanisms in response to immunization with A. niger α-1,3-glucan. Our results, which have clearly demonstrated the response of the insect immune system to this fungal cell wall component, will help in understanding the α-1,3-glucan role in immune response against fungal pathogens not only in insects but also in mammals, including humans.


Asunto(s)
Apolipoproteínas/inmunología , Aspergilosis/inmunología , Glucanos/inmunología , Hemocitos/inmunología , Inmunidad Celular , Mariposas Nocturnas , Animales , Apolipoproteínas/metabolismo , Aspergillus niger/inmunología , Aspergillus niger/metabolismo , Pared Celular/química , Modelos Animales de Enfermedad , Glucanos/metabolismo , Hemocitos/microbiología , Interacciones Microbiota-Huesped , Larva/inmunología , Larva/microbiología , Mariposas Nocturnas/inmunología , Mariposas Nocturnas/microbiología
20.
Plants (Basel) ; 9(1)2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31947694

RESUMEN

Various phytochemical studies have revealed that jackfruit (Artocarpus heterophyllus Lam.) is rich in bioactive compounds, including carotenoids, flavonoids, volatile acids, tannins, and lectins. The aim of the study was to analyze the biological activity of water-soluble polysaccharide (WSP) isolated from jackfruit and to assess its immunomodulatory, cytotoxic, and anti-oxidative effects on human colon carcinoma cells in vitro. The neutral red (NR) uptake assay revealed no toxic influence of the polymer on the viability of tumor cells (HT29 and SW620). After 24 h and 48 h of incubation, the cellular viability was not lower than 94%. The metabolic activity of the cells (MTT) at the compound concentration of 250 µg/mL was higher than 92% in comparison to the control. WSP (250 µg/mL) exerted no significant effect on the morphology of the cells was determined by May-Grünwald-Giemsa staining. WSP changed nitric oxide (NOx) production by the tumor cells depending on the time of incubation and prior 2-h stimulation of the cells with E. coli 0111:B4 LPS. It significantly stimulated IL-1ß production by the tumor cells. The IL-6 level increased but that of IL-10 decreased by a WSP concentration-dependent manner. No such effect was detected in SW620. The WSP had antioxidant properties. In conclusion, water-soluble polysaccharide isolated from A. heterophyllus exhibits significant biological activity towards many types of both normal and cancerous cells. Therefore, it may be considered as a useful agent in the protection of human health or in functional and dietary nutrition.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA