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1.
PLoS One ; 15(1): e0225672, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923175

RESUMO

The aim of this study was to purify potential allergenic components of Vespa velutina venom, the yellow legged Asian Hornet, and perform a preliminary characterization of the purified proteins. Starting from the whole venom of V.velutina, several chromatographic steps allowed to purify the phospholipase (named Vesp v 1), as well as the antigen 5 (Vesp v 5, the only allergenic component described as such so far). The two hyaluronidase isoforms found (Vesp v 2A and Vesp v 2B) cannot be separated from each other, but they are partially purified and characterized. Purity of the isolated proteins in shown by SDSPAGE, as well as by the results of the N-terminal sequencing. This characterization and nLC-MS/MS data provide most of the sequence for Vesp v 1 and Vesp v 5 (72 and 84% coverage, respectively), confirming that the whole sequences of the isolated natural components match with the data available in public transcriptomic databases. It is of particular interest that Vesp v 1 is a glycosylated phospholipase, a fact that had only described so far for the corresponding allergen components of Dolichovespula maculata and Solenopsis invicta. The availability of the complete sequences of Vespa velutina components permits comparison with homologous sequences from other Hymenoptera. These data demonstrate the higher similarity among the species of the genera Vespa and Vespula, in comparison to Polistes species, as it is especially observed with the hyaluronidases isoforms: the isoform Vesp v 2A only exists in the former genera, and not in Polistes; in addition, the most abundant isoform (Vesp v 2B) exhibits 93% sequence identity with the Ves v 2 isoform of Vespula vulgaris. Finally, the isolated components might be useful for improving the diagnosis of patients that could be allergic to stings of this invasive Asian hornet, as it has been the case of an improved diagnosis and treatment of other Hymenoptera-sensitized patients.


Assuntos
Hialuronoglucosaminidase/metabolismo , Proteínas de Insetos/metabolismo , Fosfolipases/metabolismo , Venenos de Vespas/enzimologia , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Hialuronoglucosaminidase/química , Hialuronoglucosaminidase/isolamento & purificação , Proteínas de Insetos/química , Proteínas de Insetos/isolamento & purificação , Isoenzimas/química , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Nanotecnologia , Fosfolipases/química , Fosfolipases/isolamento & purificação , Alinhamento de Sequência , Espectrometria de Massas em Tandem , Venenos de Vespas/química , Venenos de Vespas/isolamento & purificação , Venenos de Vespas/metabolismo , Vespas
2.
Biochimie ; 169: 106-120, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31288050

RESUMO

Porcine pancreatic extracts (PPE), also named pancreatin, are commonly used as a global source of pancreatic enzymes for enzyme replacement therapy in patients with exocrine pancreatic insufficiency. They are considered as a good substitute of human pancreatic enzymes and they have become a material of choice for in vitro models of digestion. Nevertheless, while the global PPE contents in lipase, protease and amylase activities are well characterized, little is known about individual enzymes. Here we characterized the lipase, phospholipase, cholesterol esterase and galactolipase activities of PPE and compared them with those of porcine (PPJ) and human (HPJ) pancreatic juices. The phospholipase to lipase activity ratio was similar in PPJ and HPJ, but was 4-fold lower in PPE. The galactolipase and cholesterol esterase activities were found at lower levels in PPJ compared to HPJ, and they were further reduced in PPE. The enzymes known to display these activities in HPJ, pancreatic lipase-related protein 2 (PLRP2) and carboxylester hydrolase/bile salt-stimulated lipase (CEH/BSSL), were identified in PPJ using gel filtration experiments, SDS-PAGE and LC-MS/MS analysis. The galactolipase and cholesterol esterase activities of PPE indicated that PLRP2 and CEH/BSSL are still present at low levels in this enzyme preparation, but they were not detected by mass spectrometry. Besides differences between porcine and human enzymes, the lower levels of phospholipase, galactolipase and cholesterol esterase activities in PPE are probably due to some proteolysis occurring during the production process. In conclusion, PPE do not provide a full substitution of the lipolytic enzymes present in HPJ.


Assuntos
Carboxilesterase/química , Fármacos Gastrointestinais/química , Lipase/química , Suco Pancreático/química , Pancreatina/química , Esterol Esterase/química , Sequência de Aminoácidos , Animais , Carboxilesterase/isolamento & purificação , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/isolamento & purificação , Ensaios Enzimáticos , Estabilidade Enzimática , Insuficiência Pancreática Exócrina/tratamento farmacológico , Fármacos Gastrointestinais/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Cinética , Lipase/isolamento & purificação , Pâncreas/química , Pâncreas/enzimologia , Pancreatina/isolamento & purificação , Fosfolipases/química , Fosfolipases/isolamento & purificação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Esterol Esterase/isolamento & purificação , Suínos
3.
J Mol Microbiol Biotechnol ; 28(3): 99-106, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30149390

RESUMO

Phospholipases are classified in different enzyme families according to the ester bond they cleave within phospholipids. The use of phospholipases in industrial processes has prompted the search for new enzymes with differential properties. A gene encoding a novel phospholipase (PLP_2.9) was identified in the genome of the thermophilic strain Thermus sp. 2.9. The analysis of the primary sequence unveiled a patatin-like domain. The alignment of the amino acid sequence of PLP_2.9 to other bacterial patatin-related proteins showed that the four blocks characteristic of this type of phospholipases and the amino acids representing the catalytic dyad are conserved in this protein. PLP_2.9 was overexpressed in Escherichia coli and the purified enzyme was characterized biochemically. PLP_2.9 hydrolyzed p-nitrophenyl palmitate at alkaline pH over a wide range of temperatures (55-80°C), showing high thermostability. PLP_2.9 displayed phospholipase A and acyltransferase activities on egg yolk phosphatidylcholine. Due to its high thermostability, PLP_2.9 has potential applications as a catalyst in several industrial processes.


Assuntos
Aciltransferases/química , Aciltransferases/genética , Fosfolipases/química , Fosfolipases/genética , Thermus/enzimologia , Thermus/genética , Aciltransferases/isolamento & purificação , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Sequência de Bases , Clonagem Molecular , Ativação Enzimática , Ensaios Enzimáticos , Estabilidade Enzimática , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Cinética , Metabolismo dos Lipídeos , Fosfolipases/isolamento & purificação , Análise de Sequência de Proteína , Especificidade por Substrato , Temperatura
4.
Methods Mol Biol ; 1835: 243-283, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30109657

RESUMO

Immobilization of lipases and phospholipases, mainly on water-insoluble carriers, helps in their economic reusing and in the development of continuous bioprocesses. Design of efficient lipase and phospholipase-immobilized systems is rather a difficult task. A lot of research work has been done in order to optimize immobilization techniques and procedures and to develop efficient immobilized systems. We conceived a new strategy for the rational design of immobilized derivatives (RDID) in favor of the successful synthesis of optimal lipase and phospholipase-immobilized derivatives, aiming the prediction of the immobilized derivative's functionality and the optimization of load studies. The RDID strategy begins with the knowledge of structural and functional features of synthesis components (protein and carrier) and the practical goal of the immobilized product. The RDID strategy was implemented in a software named RDID1.0. The employment of RDID allows selecting the most appropriate way to prepare immobilized derivatives more efficient in enzymatic bioconversion processes and racemic mixture resolution.


Assuntos
Enzimas Imobilizadas , Lipase , Fosfolipases , Biologia Sintética , Biocatálise , Ativação Enzimática , Interações Hidrofóbicas e Hidrofílicas , Lipase/química , Lipase/isolamento & purificação , Lipase/metabolismo , Modelos Moleculares , Fosfolipases/química , Fosfolipases/isolamento & purificação , Fosfolipases/metabolismo , Software , Relação Estrutura-Atividade , Biologia Sintética/métodos
5.
J Mycol Med ; 28(3): 437-442, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29778633

RESUMO

Candida species are the commensal organisms of human and animal mucosa that cause a wide range of debilitating diseases in immunocompromised patients and other susceptible individuals. The present study aimed to investigate the ability of clinical isolates of various Candida species to produce proteinase and phospholipase, hydrophobicity and biofilm forming ability that assumed to have a vital role in Candida pathogenicity. Eighty-four Candida strains belonged to Candida albicans (44.1%), C. glabrata (5.9%), C. guilliermondii (5.9%), C. krusei (10.8%), C. parapsilosis (26.2%), and C. tropicalis (7.1%) were examined for proteinase and phospholipase production, cell surface hydrophobicity and biofilm forming ability. The production of proteinase and phospholipase was detected in 81 (96.4%) and 79 (94.1%) of the strains, respectively. C. albicans showed the highest proteinase and phospholipase activity (mean Pz values of 0.42±0.25 and 0.72±0.28) and biofilm formation ability (0.66±0.22). C. parapsilosis had the highest hydrophobicity (42.97±16.1), which showed a good correlation with biofilm formation ability. A considerable percentage of non-albicans Candida strains produced significant amounts of proteinase and phospholipase with a good ability of biofilm formation in vitro. Taken together, our results further substantiated that enzymatic activity, hydrophobicity and the ability for biofilm formation are important virulence factors which may be account for pathogenicity of various Candida species distributed in albicans and non-albicans groups.


Assuntos
Candida , Candidíase/microbiologia , Peptídeo Hidrolases/metabolismo , Fosfolipases/metabolismo , Biofilmes , Candida/enzimologia , Candida/isolamento & purificação , Candida/patogenicidade , Candida/fisiologia , Infecção Hospitalar/microbiologia , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Peptídeo Hidrolases/análise , Peptídeo Hidrolases/isolamento & purificação , Fosfolipases/análise , Fosfolipases/isolamento & purificação , Fatores de Virulência/fisiologia
6.
Toxicon ; 114: 31-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26908291

RESUMO

The Azemiops snakes are pit-less and phylogenetically located at the Crotalinae and Viperinae divergence. cDNAs encoding five Azemiops venom phospholipase (sPLA2) molecules were cloned and sequenced; their signal-peptides were similar to those of crotalid sPLA2s. Based on their calculated pI-values and residue-49 substitutions, they were designated as Af-E6, Af-N49a, Af-N49a1, Af-N49a2, and Af-N49b, respectively. The first three isoforms, comprising 3-4% of the venom proteins, were purified by reversed-phase HPLC. Af-E6 is catalytically active and has >80% sequence-similarity to other Glu(6)-PLA2 (a pitviper venom-marker). Results of phylogenetic analyses reveal that acidic Af-N49a and Af-N49a1 are rather unique and loosely linked with crotalid PLA2s, while Af-N49b is related to the viperid PLA2s with Ser(1) substitution. Notably, the Asn(49)-substitutions in these molecules imply catalytic-independent mechanisms. The 3D-models of Af-E6 and Af-N49a have surface electropotential maps similar to each other and to those of antiplatelet PLA2s, while the Af-N49b model is similar to basic and myotoxic sPLA2 molecules. From Azemiops feae and four other Viperidae, we cloned five novel Cys-rich secretory proteins (CRISPs). Azemiops CRISP and natriuretic-peptide precursors share more sequence similarities with those of crotalid venoms than with viperid venoms, further supporting the theory that Azemiops are sister taxons to pit vipers, especially Tropedolaemus.


Assuntos
Fosfolipases/química , Proteínas de Répteis/química , Venenos de Víboras/química , Viperidae/classificação , Animais , Clonagem Molecular , DNA Complementar/química , Modelos Moleculares , Fosfolipases/genética , Fosfolipases/isolamento & purificação , Filogenia , Estrutura Terciária de Proteína , Proteínas de Répteis/genética , Proteínas de Répteis/isolamento & purificação , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie , Viperidae/genética , Viperidae/metabolismo
7.
Appl Environ Microbiol ; 81(5): 1847-58, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25548058

RESUMO

Identification of proteins that were present in a polyhydroxybutyrate (PHB) granule fraction isolated from Ralstonia eutropha but absent in the soluble, membrane, and membrane-associated fractions revealed the presence of only 12 polypeptides with PHB-specific locations plus 4 previously known PHB-associated proteins with multiple locations. None of the previously postulated PHB depolymerase isoenzymes (PhaZa2 to PhaZa5, PhaZd1, and PhaZd2) and none of the two known 3-hydroxybutyrate oligomer hydrolases (PhaZb and PhaZc) were significantly present in isolated PHB granules. Four polypeptides were found that had not yet been identified in PHB granules. Three of the novel proteins are putative α/ß-hydrolases, and two of those (A0671 and B1632) have a PHB synthase/depolymerase signature. The third novel protein (A0225) is a patatin-like phospholipase, a type of enzyme that has not been described for PHB granules of any PHB-accumulating species. No function has been ascribed to the fourth protein (A2001), but its encoding gene forms an operon with phaB2 (acetoacetyl-coenzyme A [CoA] reductase) and phaC2 (PHB synthase), and this is in line with a putative function in PHB metabolism. The localization of the four new proteins at the PHB granule surface was confirmed in vivo by fluorescence microscopy of constructed fusion proteins with enhanced yellow fluorescent protein (eYFP). Deletion of A0671 and B1632 had a minor but detectable effect on the PHB mobilization ability in the stationary growth phase of nutrient broth (NB)-gluconate cells, confirming the functional involvement of both proteins in PHB metabolism.


Assuntos
Proteínas de Bactérias/análise , Proteínas de Bactérias/isolamento & purificação , Cupriavidus necator/química , Grânulos Citoplasmáticos/química , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Proteoma/análise , Proteínas de Bactérias/genética , Cupriavidus necator/genética , Cupriavidus necator/metabolismo , Deleção de Genes , Hidrolases/análise , Hidrolases/genética , Hidrolases/isolamento & purificação , Microscopia de Fluorescência , Óperon , Fosfolipases/análise , Fosfolipases/genética , Fosfolipases/isolamento & purificação
8.
Rev Iberoam Micol ; 32(2): 79-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24704439

RESUMO

BACKGROUND: Candida species, in conditions of microbiota imbalance or decreased immune defenses, may be one of the main human fungal pathogens. Virulence factors constitute the mechanisms used by the fungus to avoid host defenses. AIMS: This study aimed to investigate the in vitro production of virulence factors, such as hemolytic activity, and deoxyribonuclease (DNase), proteinase, and phospholipase activities in Candida spp. METHODS: Fifty clinical isolates were analyzed for virulence factors: Candida albicans (15), Candida tropicalis (15), Candida parapsilosis (10), Candida glabrata (5), and Candida krusei (5). Hemolytic activity was determined in Sabouraud dextrose agar plates containing 3% glucose and 7% sheep red cells. Culture media containing, respectively, agar-base DNA, egg yolk, and bovine albumin were used to determine DNase, phospholipase and proteinase activities, respectively. RESULTS: Forty-eight (96%) of 50 isolates showed hemolytic activity, with 10 (20%) positive for DNase, 19 (38%) for proteinase, and 16 (32%) for phospholipase. Statistically significant differences were observed between species for phospholipase (p<0.0001) and proteinase (p<0.05) production. CONCLUSIONS: It is concluded that all species had hemolytic activity. DNase activity was detected in all species except in C. glabrata; proteinase activity was detected in C. albicans, C. tropicalis, and C. parapsilosis; and phospholipase activity was observed in C. albicans and C. tropicalis.


Assuntos
Candida/enzimologia , Proteínas Fúngicas/fisiologia , Animais , Candida/classificação , Candida/isolamento & purificação , Candida/patogenicidade , Candidíase/microbiologia , Meios de Cultura , Desoxirribonucleases/isolamento & purificação , Desoxirribonucleases/fisiologia , Eritrócitos , Proteínas Fúngicas/isolamento & purificação , Hemólise , Humanos , Peptídeo Hidrolases/isolamento & purificação , Peptídeo Hidrolases/fisiologia , Fosfolipases/isolamento & purificação , Fosfolipases/fisiologia , Ovinos , Especificidade da Espécie , Virulência
9.
Biochimie ; 95(9): 1795-806, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23796575

RESUMO

The ciliated protozoon Euplotes focardii, originally isolated from the coastal seawaters of Terra Nova Bay in Antarctica, shows a strictly psychrophilic phenotype, including optimal survival and multiplication rates at 4-5 °C. This characteristic makes E. focardii an ideal model species for identifying the molecular bases of cold adaptation in psychrophilic organisms, as well as a suitable source of novel cold-active enzymes for industrial applications. In the current study, we characterized the patatin-like phospholipase from E. focardii (EfPLP), and its enzymatic activity was compared to that of the homologous protein from the mesophilic congeneric species Euplotes crassus (EcPLP). Both EfPLP and EcPLP have consensus motifs conserved in other patatin-like phospholipases. By analyzing both esterase and phospholipase A2 activity, we determined the thermostability and the optimal pH, temperature dependence and substrates of these enzymes. We demonstrated that EfPLP shows the characteristics of a psychrophilic phospholipase. Furthermore, we analyzed the enzymatic activity of three engineered versions of the EfPLP, in which unique residues of EfPLP, Gly80, Ala201 and Val204, were substituted through site-directed mutagenesis with residues found in the E. crassus homolog (Glu, Pro and Ile, respectively). Additionally, three corresponding mutants of EcPLP were also generated and characterized. These analyses showed that the substitution of amino acids with rigid and bulky charged/hydrophobic side chain in the psychrophilic EfPLP confers enzymatic properties similar to those of the mesophilic patatin-like phospholipase, and vice versa. This is the first report on the isolation and characterization of a cold-adapted patatin-like phospholipase from eukaryotes. The results reported in this paper support the idea that enzyme thermal-adaptation is based mainly on some amino acid residues that influence the structural flexibility of polypeptides and that EfPLP is an attractive biocatalyst for industrial processes at low temperatures.


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Euplotes/fisiologia , Fosfolipases/metabolismo , Homologia de Sequência de Aminoácidos , Sequência de Aminoácidos , Clonagem Molecular , Estabilidade Enzimática , Euplotes/enzimologia , Euplotes/genética , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Fosfolipases/química , Fosfolipases/genética , Fosfolipases/isolamento & purificação , Conformação Proteica , Análise de Sequência
10.
Int J Biol Macromol ; 58: 87-94, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23545272

RESUMO

A lipase from the golden grey mullet viscera was purified to homogeneity by ammonium sulphate precipitation, gel filtration, anionic and cation exchange chromatographies. The pure enzyme tentatively named grey mullet digestive lipase (GmDL) is a monomer having a molecular mass of about 35 kDa, as determined by SDS-PAGE analysis. No similarity was found between the NH2-terminal amino acid residues of GmDL and those of other known digestive lipases. GmDL is a serine enzyme, like all known lipases from different origins. Interestingly, GmDL has not only lipase activity but also a phospholipase activity which requires the presence of Ca(2+) and bile salts. Specific activities of 64 U/mg, 55 U/mg and 63 U/mg were measured using tributyrin, olive oil emulsion or phosphatidylcholine as substrate, respectively at pH 8 and at 50°C. GmDL is therefore a thermo-active enzyme as compared to other fish lipases studied so far. It is worth to notice that grey mullet lipase was active in the presence of salt concentrations as high as 0.8M.


Assuntos
Proteínas de Peixes/isolamento & purificação , Lipase/isolamento & purificação , Fosfolipases/isolamento & purificação , Smegmamorpha , Animais , Ácidos e Sais Biliares/química , Cálcio/química , Ensaios Enzimáticos , Estabilidade Enzimática , Proteínas de Peixes/antagonistas & inibidores , Proteínas de Peixes/química , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Lactonas/química , Lipase/antagonistas & inibidores , Lipase/química , Lipólise , Azeite de Oliva , Orlistate , Fosfatidilcolinas/química , Fosfolipases/antagonistas & inibidores , Fosfolipases/química , Óleos de Plantas/química , Análise de Sequência de Proteína
11.
Appl Biochem Biotechnol ; 168(8): 2330-43, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23151966

RESUMO

An extracellular lipase from Fusarium solani strain (F. solani lipase (FSL)) was purified to homogeneity by ammonium sulphate precipitation, gel filtration and anion exchange chromatography. The purified enzyme has a molecular mass of 30 kDa as estimated by sodium dodecyl sulphate polyacrylamide gel electrophoresis. The 12 NH(2)-terminal amino acid residues showed a high degree of homology with a putative lipase from the fungus Necteria heamatoccocae. It is a serine enzyme, like all known lipases from different origins. Interestingly, FSL has not only lipase activity but also a high phospholipase activity which requires the presence of Ca(2+) and bile salts. The specific activities of FSL were about 1,610 and 2,414 U/mg on olive oil emulsion and egg-yolk phosphatidylcholine as substrates, respectively, at pH 8.0 and 37 °C. The (phospho)lipase enzyme was stable in the pH range of 5-10 and at temperatures below 45 °C.


Assuntos
Fusarium/enzimologia , Fusarium/isolamento & purificação , Fosfolipases/isolamento & purificação , Fosfolipases/metabolismo , Sequência de Aminoácidos , Ácidos e Sais Biliares/farmacologia , Biocatálise/efeitos dos fármacos , Cálcio/farmacologia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Lactonas/farmacologia , Orlistate , Fosfolipases/química , Temperatura , Árvores/microbiologia , Madeira/microbiologia
12.
Toxins (Basel) ; 4(7): 536-53, 2012 07.
Artigo em Inglês | MEDLINE | ID: mdl-22852067

RESUMO

The mechanism of phagosome escape by intracellular pathogens is an important step in the infectious cycle. During the establishment of anthrax, Bacillus anthracis undergoes a transient intracellular phase in which spores are engulfed by local phagocytes. Spores germinate inside phagosomes and grow to vegetative bacilli, which emerge from their resident intracellular compartments, replicate and eventually exit from the plasma membrane. During germination, B. anthracis secretes multiple factors that can help its resistance to the phagocytes. Here the possible role of B. anthracis toxins, phospholipases, antioxidant enzymes and capsules in the phagosomal escape and survival, is analyzed and compared with that of factors of other microbial pathogens involved in the same type of process.


Assuntos
Bacillus anthracis/patogenicidade , Fagossomos/metabolismo , Fagossomos/microbiologia , Animais , Antraz/microbiologia , Antraz/patologia , Antígenos de Bactérias/isolamento & purificação , Antígenos de Bactérias/toxicidade , Antioxidantes/metabolismo , Bacillus anthracis/crescimento & desenvolvimento , Bacillus anthracis/metabolismo , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/isolamento & purificação , Toxinas Bacterianas/toxicidade , Modelos Animais de Doenças , Humanos , Glicoproteínas de Membrana/isolamento & purificação , Glicoproteínas de Membrana/toxicidade , Fagócitos/metabolismo , Fagócitos/microbiologia , Fagócitos/patologia , Fosfolipases/genética , Fosfolipases/isolamento & purificação , Fosfolipases/toxicidade , Esporos Bacterianos/citologia , Esporos Bacterianos/patogenicidade
13.
Methods Mol Biol ; 861: 495-523, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22426737

RESUMO

Mammal, plant, and mainly microbial phospholipases are continuously being studied, experimented, and some of them are even commercially available at industrial scale for food industry. This is because the use of phospholipases in the production of specific foods leads to attractive advantages, such as yield improvement, energy saving, higher efficiency, improved properties, or better quality of the final product. Furthermore, biocatalysis approaches in the food industry are of current interest as non-pollutant and cleaner technologies. The present chapter reviews the most representative examples of the use of phospholipases in food industry, namely edible oils, dairy, and baking products, emulsifying agents, as well as the current trend to the development of novel molecular species of phospholipids with added-value characteristics.


Assuntos
Proteínas de Bactérias/química , Tecnologia de Alimentos/métodos , Proteínas Fúngicas/química , Química Verde/métodos , Fosfolipases/química , Laticínios , Gorduras Insaturadas na Dieta/síntese química , Gema de Ovo/química , Emulsificantes/síntese química , Fosfolipases/isolamento & purificação , Fosfolipídeos/síntese química
14.
Anal Bioanal Chem ; 402(9): 2737-48, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22349324

RESUMO

The ammodytoxins (Atxs) are neurotoxic phospholipases which occur in Vipera ammodytes ammodytes (Vaa) snake venom. There are three Atx isoforms, A, B, and C, which differ in only five amino acid positions at the C-terminus but differ substantially in their toxicity. The objective of this study was to establish an analytical method for unambiguous identification of all three isoforms and to use the method to assess a procedure for purification of the most toxic phospholipase, AtxA, from the venom. Isolation procedure for AtxA consisted of isolation of Atx-cross-reactive material (proteins recognized by anti-Atx antibodies), by use of an affinity column, then cation exchange on CIM (Convective Interaction Media) disks. The purification procedure was monitored by means of reversed-phase chromatography (RPC) and mass spectrometry (MS). Although previous cation exchange of the pure isoforms enabled separate elution of AtxA from B and C, separation of AtxA from Atxs mixture was not accomplished. RPC was not able to separate the Atx isoforms, whereas an MS based approach proved to be more powerful. Peptides resulting from tryptic digestion of Atxs which enable differentiation between the three isoforms were successfully detected and their sequences were confirmed by post-source decay (PSD) fragmentation. Separation of Atx isoforms by ion-exchange chromatography is most presumably prevented by Atxs heterodimer formation. The tendency of Atxs to form homodimers and heterodimers of similar stability was confirmed by molecular modeling.


Assuntos
Cromatografia/métodos , Proteínas Neurotóxicas de Elapídeos/química , Proteínas Neurotóxicas de Elapídeos/isolamento & purificação , Fosfolipases/química , Fosfolipases/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Venenos de Víboras/química , Sequência de Aminoácidos , Animais , Proteínas Neurotóxicas de Elapídeos/toxicidade , Isoenzimas/química , Isoenzimas/isolamento & purificação , Isoenzimas/toxicidade , Modelos Moleculares , Dados de Sequência Molecular , Fosfolipases/toxicidade , Venenos de Víboras/toxicidade , Viperidae
15.
Toxicon ; 57(6): 841-50, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21356226

RESUMO

A homodimeric acidic PLA(2) (RVVA-PLA(2)-I) of 58.0 kDa molecular weight purified from Russell's viper (Daboia russelli) venom demonstrated dose-dependent catalytic, strong anticoagulant and indirect hemolytic activities and inhibited blood coagulation cascade in both enzymatic and non-enzymatic mechanisms. In in vitro condition, RVVA-PLA(2)-I showed preferential hydrolysis of phosphatidylcholine with a K(m) and V(max) values of 0.65 mM and 28.9 µmol min(-1), respectively. Biochemical study and GC-analysis of plasma phospholipids hydrolysis by PLA(2) revealed that anticoagulant activity of RVVA-PLA(2)-I was partly attributed by the enzymatic hydrolysis of pro-coagulant phospholipids PC, followed by PS. The spectrofluorometric and gel-filtration analyses documented binding of RVVA-PLA(2)-I with activated factor X and PC; however, it does not bind with factor Va, prothrombin and thrombin. Therefore, this anticoagulant PLA(2) inhibits the blood coagulation cascade non-enzymatically by binding with coagulation factor Xa, even in the absence of phospholipids and Ca(2+) and thus slows down the blood coagulation by partially inhibiting the prothrombin activation. Chemical modification of essential amino acids present in the active site, neutralization with Azadirachta indica leaves extract (AIPLAI) and heat-inactivation study reinforce the association of catalytic and anticoagulant activity of RVVA-PLA(2)-I and also throw a light on its non-enzymatic mechanism of anticoagulant action.


Assuntos
Anticoagulantes/isolamento & purificação , Daboia , Inibidores do Fator Xa , Fosfolipases/isolamento & purificação , Fosfolipídeos/metabolismo , Venenos de Víboras/enzimologia , Animais , Anticoagulantes/toxicidade , Cálcio/metabolismo , Eletroforese em Gel de Poliacrilamida , Fluorescência , Hidrólise , Índia , Fosfolipases/toxicidade , Fosfolipídeos/sangue , Protrombina
16.
Appl Biochem Biotechnol ; 164(7): 991-1022, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21302142

RESUMO

Significant studies on phospholipases optimization, characterization, physiological role and industrial potential have been conducted worldwide. Some of them have been directed for biotechnological advances such as gene discovery and functional enhancement by protein engineering. Others reported phospholipases as virulence factor and major cause of pathophysiological effects. A general overview on phospholipase is needed for the identification of new reliable and efficient phospholipase, which would be potentially used in number of industrial and medical applications. Phospholipases catalyse the hydrolysis of one or more ester and phosphodiester bonds of glycerophospholipids. They vary in site of action on phospholipid which can be used industrially for modification/production of new phospholipids. Catalytically active phospholipase mainly use phosphatidylcholine as major substrate, but they can also show specificity with other phospholipids. Several accurate phospholipase assay methods are known, but a rapid and reliable method for high-throughput screening is still a challenge for efficient supply of superior phospholipases and their practical applications. Major application of phospholipase is in industries like oil refinery, health food manufacturing, dairy, cosmetics etc. All types of phospholipases can be involved as virulence factor. They can also be used as diagnostic markers for microbial infection. The importance of phospholipase in virulence is proven and inhibitors of the enzyme can be used as candidate for preventing the associated disease.


Assuntos
Biotecnologia/métodos , Fosfatidilcolinas/metabolismo , Fosfolipases , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Bioensaio , Biomarcadores/análise , Biotecnologia/tendências , Catálise , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Humanos , Hidrólise , Cinética , Fosfolipases/química , Fosfolipases/classificação , Fosfolipases/isolamento & purificação , Fosfolipases/metabolismo , Especificidade por Substrato , Fatores de Virulência/análise
17.
Braz. j. microbiol ; Braz. j. microbiol;41(1): 19-23, Jan.-Mar. 2010. tab
Artigo em Inglês | LILACS | ID: lil-531728

RESUMO

Patients suffering of diseases that affect central nervous system may be considered more susceptible to the infectious diseases of mouth. Sixty-nine patients suffering of cerebral palsy, Down's syndrome and metal retardation were submitted to saliva examination for the presence of Candida spp. before and after a procedure of dental cleaning. The isolates were submitted to assay for verifying phospholipase production. 55.10 percent of the patients provided isolation of Candida spp. The frequency of isolation obtained before dental procedure was: C. albicans (83.33 percent), C. krusei (8.33 percent) and C. kefyr, C. parapsilosis and C. glabrata (2.78 percent each). The frequency after the procedure was: C. albicans (68.57 percent), C. parapsilosis (11.43 percent), C. krusei and C. kefyr (8.57 percent each) and Candida glabrata (2.86 percent). We verified significantly difference (p < 0.01) between populations obtained at the two examinations. Phospholipase production was verified only among C. albicans strains and the proportion of producers was higher when testing isolates obtained after dental cleaning procedure. Studies focused on Candida spp. isolation are useful for better comprehension of the role of these yeasts on the oral flora from patients with cerebral palsy, Down's syndrome and metal retardation.


Assuntos
Humanos , Criança , Candidíase Bucal , Paralisia Cerebral , Candida/isolamento & purificação , Síndrome de Down , Fosfolipases/análise , Fosfolipases/isolamento & purificação , Deficiência Intelectual , Escovação Dentária , Técnicas e Procedimentos Diagnósticos , Epidemiologia , Métodos
18.
Bioresour Technol ; 101(1): 366-71, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19695876

RESUMO

Crab digestive phospholipase (CDPL) was purified from the hepatopancreas of Carcinus mediterraneus crabs. Homogeneous enzyme was obtained after two chromatography steps: anion exchange and size exclusion HPLC column. Homogeneous CDPL has a molecular mass of 14 kDa as determined by SDS/PAGE analysis. Unlike known digestive phospholipases like porcine PLA(2) (PPPL), CDPL displayed its maximal activity at 50 degrees C and not at 37 degrees C. A specific activity of 40 U/mg for the purified CDPL was measured using PC as substrate under optimal conditions (pH 8 and 50 degrees C) in the presence of 8 mM sodium deoxycholate (NaDC) and 10 mM CaCl(2). In contrast to PPPL, purified CDPL was completely inactivated at 60 degrees C. The N-terminal sequence was determined by automatic Edman degradation. No similarity between 12 N-terminal amino acid residues of CDPL was found with those of known digestive phospholipases. CDPL appears to be a new member of invertebrate phospholipases, and it is potentially useful for treat phospholipid-rich industrial effluents, or to synthesize useful chemical compounds which can be used in the food industry.


Assuntos
Decápodes/enzimologia , Pâncreas/enzimologia , Fosfolipases/química , Fosfolipases/isolamento & purificação , Animais , Ativação Enzimática , Estabilidade Enzimática
19.
Anaerobe ; 15(3): 91-4, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19150408

RESUMO

Enzyme preparations obtained from Prevotella intermedia culture supernatants were partially purified by ammonium sulfate precipitation and ion-exchange column chromatography. Hydrolytic activities were revealed by an assay that uses silicic acid thin layer chromatography to separate the products derived from (14)C-labeled phosphatidyl-choline (PC) hydrolysis. These products were then measured by liquid scintillation spectrometry after iodine visualization. The assays revealed linearity of substrate depletion and product formation with respect to time and protein concentration up to 30 min of incubation. The products had retention times consistent with lyso-phospholipids and phosphoryl-choline. These data strongly suggests the presence of both phospholipase A (PL-A) and phospholipase C (PL-C) activities.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Meios de Cultura/química , Fosfolipases/isolamento & purificação , Prevotella intermedia/enzimologia , Radioisótopos de Carbono/metabolismo , Fracionamento Químico , Cromatografia por Troca Iônica , Cinética , Fosfatidilcolinas/metabolismo
20.
Mycoses ; 50(5): 407-11, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17714362

RESUMO

This investigation was designed to evaluate the frequency of erythematous candidosis (EC) and Candida species, proteinase and phospholipase exoenzyme production, and to compare clinical features in patients with complete dentures and HIV+/Acquired Immunodeficiency Disease Syndrome (AIDS). Fifty-one patients were selected from a total of 285 with EC: denture wearers (n = 30) and HIV+/AIDS (n = 21). The yeast prevalence and the production of exoenzymes, such as proteinase and phospholipase by Candida species were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) electrophoresis. The frequency of Candida albicans was significantly higher (P < 0.05) in both groups although other yeast species (Candida glabrata, Candida krusei, Candida parapsilosis, Candida guilliermondi and Candida tropicalis) were also found. Candida albicans showed greater levels of proteinase production in the denture wearers, when compared with the HIV+/AIDS group. There was no difference between groups with regard to phospholipase production. The protein bands presented similar molecular weights, showing the presence of proteinases in both groups. It could be concluded that the clinical manifestation of EC may be related to its proteinase production capacity. Combination therapies using proteinase inhibitors play an important role in inhibiting exoenzyme production by Candida species, mainly C. albicans.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Candida/isolamento & purificação , Candidíase Bucal/epidemiologia , Candidíase Bucal/microbiologia , Prótese Total/microbiologia , Infecções por HIV/epidemiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/microbiologia , Brasil/epidemiologia , Candida/classificação , Comorbidade , Prótese Total/estatística & dados numéricos , Eletroforese em Gel de Poliacrilamida , Endopeptidases/análise , Endopeptidases/isolamento & purificação , Feminino , Infecções por HIV/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Boca/microbiologia , Técnicas de Tipagem Micológica , Fosfolipases/análise , Fosfolipases/isolamento & purificação , Prevalência
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