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1.
Ying Yong Sheng Tai Xue Bao ; 31(3): 959-968, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32537993

RESUMO

We investigated the signal relationship between phospholipase Dα1 (PLDα1) and the gas signal molecule hydrogen sulfide (H2S) in Arabidopsis thaliana response to the allelopathy of diterpenoid oridonin. The wild type Arabidopsis Columbia (WT), phospholipase Dα1 (PLDα1) deletion mutant pldα1, D-/L-cysteine desulfyrase synthetic deletion mutant d-cdes and l-cdes seedlings were used as experiment materials, while 60 µmol·L-1 oridonin was applied as treatment concentration. The results showed that oridonin significantly increased H2S content, PLD and D-/L-CDes activities, and gene expressions of PLDα1 and D-/L-CDes in WT. Under oridonin treatment, the D-CDes and L-CDes activities of pldɑ1 seedlings were significantly lower than those of WT. Both D-CDes and L-CDes activities increased after exogenous addition of phosphatidic acid (PA) and were higher than those of WT. Oridonin significantly inhibited root growth of four lines, with d-cdes and l-cdes being more sensitive to oridonin. Application of NaHS promoted root growth and endogenous H2S production of four lines under oridonin treatment, while application of PA increased root growth and endogenous H2S production in WT, pldɑ1 and l-cdes, but had no effect in d-cdes. These results indicated that PLDα1 and H2S played a vital role in driving the response of Arabidopsis to oridonin, and that PLDα1/PA was located at the upstream of D-CDes to participate the regulation of the H2S production and root growth.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Sulfeto de Hidrogênio , Alelopatia , Diterpenos de Caurano , Fosfolipases
3.
Toxicon ; 180: 62-78, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32283106

RESUMO

Lizards of the Helodermatidae (Anguimorpha) family consist of at least two well recognized species: Heloderma horridum horridum and Heloderma suspectum suspectum. They contain specialized glands in their jaws that produce venomous secretions that causes envenoming symptoms to bitten animals. One way to study proteins from such secretions is by RNA-seq; a powerful molecular tool to characterize the transcriptome of such specialized gland, and its protein secretions. The total RNA from venom gland tissues of H. horridum horridum was extracted and a cDNA library was constructed and sequenced. Overall, 114,172 transcripts were found, and 199 were annotated based on sequence similarities to previously described peptides/proteins. Transcripts coding for putative exendins, defensins, natriuretics and serine protease inhibitors were the most highly expressed. Transcripts that code for several putative serine proteases, phospholipases, metalloproteases, lipases, L-amino oxidase and nucleases were also found. Some of the novel identified transcripts were translationally controlled tumor proteins, venom factors, vespryns, waprins, lectins, cystatins and serine protease inhibitors. All these new protein structures may contribute to a better understanding of the venomous secretions of the Helodermatidae family.


Assuntos
Lagartos/genética , Peçonhas , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequenciamento de Nucleotídeos em Larga Escala , Lagartos/metabolismo , Peptídeos , Fosfolipases , Transcriptoma
4.
Rev Soc Bras Med Trop ; 53: e20190214, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049200

RESUMO

INTRODUCTION: The aim of this study was to evaluate some virulence factors in Candida albicans isolates from patients with onychomycosis and determine the correlation between these factors and the antifungal resistance profile. METHODS: Seventy species of C. albicans were confirmed using polymerase chain reaction amplification of the HWP1 gene. According to the Clinical & Laboratory Standards Institute guidelines, the susceptibility profile of four antifungal agents was investigated, and the production of aspartyl protease, phospholipase, haemolysin, and biofilm was determined. The correlation between these profiles was also investigated. RESULTS: The isolates indicated different levels of resistance and production of virulence factors. Significant correlations were observed between the minimum inhibitory concentration (MIC) of fluconazole/itraconazole and biofilm production, between phospholipase production and fluconazole/itraconazole MIC, and between fluconazole MIC and hemolytic activity in C. albicans isolates. The results also showed significant correlations between phospholipase activity and biofilm production. CONCLUSIONS: Our findings will contribute to a better understanding of the pathogenesis of C. albicans and characterize the relationship between virulence factors and antifungal resistance, which may suggest new therapeutic strategies considering the possible involvement of the virulence mechanism in the effectiveness of treatment.


Assuntos
Antifúngicos/farmacologia , Candida albicans/patogenicidade , Unhas/microbiologia , Onicomicose/microbiologia , Fatores de Virulência , Ácido Aspártico Proteases/biossíntese , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/ultraestrutura , Farmacorresistência Fúngica , Hemólise , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Fosfolipases/biossíntese , Reação em Cadeia da Polimerase
5.
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
6.
Enzyme Microb Technol ; 132: 109388, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731951

RESUMO

Conjugated linolenic acid (CLA) has important health effects, and their phospholipids forms (PL) are advantageous vehicles of this bioactive agent. Acidolysis of soybean phosphatidylcholine (PC) with conjugated linolenic acid (CLA) catalyzed by Lecitase® Ultra immobilized on Duolite A658 was studied. This reaction is typically limited by hydrolysis, producing 60-90 % of lyso- and glycero-PC and yielding low the process efficiency. Drying the amphiphilic PC material was found the key factor for maximal diacylglycerol phosphatidylcholines (PC) production and different drying approaches were studied to maximize the formation of PC rich in CLA in a solvent free process. PC lyophilization for 24 h getting dry solid appearance (PC; 783 ±â€¯11 mg water/Kg PC) or other standard protocols to reduce water content/activity of reaction medium, did not improve the reaction performance. However, adding 4 extra days to the second step of lyophilization at high vacuum (1 Pa) and moderate temperature (20 °C), followed by further PC dehydration with molecular sieves, drastically reduced the hydrolysis process by achieving a extensive PC dehydration (279 ±â€¯4 mg water/Kg PC), obtaining for the first time >99% molar yield of diacyl-PC product. After 24 h of reaction, a diacyl-PC product with 72.3% CLA content was obtained. PC molecules containing two CLA were the major species formed.


Assuntos
Enzimas Imobilizadas/química , Liofilização/métodos , Fosfolipases/química , Fosfolipídeos/química , Catálise , Hidrólise , Fosfatidilcolinas/química , Pró-Fármacos , Ácido alfa-Linoleico/química
7.
Food Chem ; 311: 126017, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31864184

RESUMO

Phospholipid gum mesostructures formed in crude soybean oil after water degumming (WD) and enzymatic degumming (ED) were studied at a range of phospholipid and water concentrations. For ED, phospholipase C (PLC), phospholipase A2 (PLA2) and a mixture of phospholipases Purifine 3G (3G) were used. Both WD and ED resulted in lamellar liquid-crystalline phases, however, of different topology. The dependence of the bilayer spacings (as observed by SANS and SAXS) on the ratio between amount of water and amphiphilic lipids differed for WD and PLA2 ED vs PLC and 3G ED. This difference was also observed for dynamics at molecular scale as observed by time-domain (TD) NMR and attributed to partial incorporation of diglycerides and free fatty acids into gum bilayers after PLC and 3G ED. Feasibility of using TD-NMR relaxometry for quantification of the gum phase and estimation of degumming efficiency was demonstrated.


Assuntos
Manipulação de Alimentos/métodos , Fosfolipases/metabolismo , Fosfolipídeos/química , Gomas Vegetais/química , Soja/química , Água/química , Diglicerídeos/química , Ácidos Graxos/química , Cristais Líquidos , Espectroscopia de Ressonância Magnética , Espalhamento a Baixo Ângulo , Óleo de Soja/química , Difração de Raios X
8.
Int J Mol Sci ; 21(1)2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31877740

RESUMO

The SGNH family esterases are highly effective biocatalysts due to their strong catalytic efficiencies, great stabilities, relatively small sizes, and ease of immobilization. Here, a novel SGNH family esterase (LaSGNH1) from Lactobacillus acidophilus NCFM, which has homologues in many Lactobacillus species, was identified, characterized, and immobilized. LaSGNH1 is highly active towards acetate- or butyrate-containing compounds, such as p-nitrophenyl acetate or 1-naphthyl acetate. Enzymatic properties of LaSGNH1, including thermal stability, optimum pH, chemical stability, and urea stability, were investigated. Interestingly, LaSGNH1 displayed a wide range of substrate specificity that included glyceryl tributyrate, tert-butyl acetate, and glucose pentaacetate. Furthermore, immobilization of LaSGNH1 by crosslinked enzyme aggregates (CLEAs) showed enhanced thermal stability and efficient recycling property. In summary, this work paves the way for molecular understandings and industrial applications of a novel SGNH family esterase (LaSGNH1) from Lactobacillus acidophilus.


Assuntos
Proteínas de Bactérias/metabolismo , Enzimas Imobilizadas/metabolismo , Lactobacillus acidophilus/enzimologia , Fosfolipases/metabolismo , Proteínas de Bactérias/química , Sítios de Ligação , Sequência Conservada , Estabilidade Enzimática , Enzimas Imobilizadas/química , Lactobacillus acidophilus/classificação , Lactobacillus acidophilus/genética , Fosfolipases/química , Ligação Proteica , Especificidade por Substrato
9.
Adv Exp Med Biol ; 1197: 79-95, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31732936

RESUMO

Porphyromonas gingivalis is an oral pathogen with the ability to induce oral dysbiosis and periodontal disease. Nevertheless, the mechanisms by which P. gingivalis could abrogate the host-microbe symbiotic relationship leading to oral dysbiosis remain unclear. We have recently demonstrated that P. gingivalis specifically increased the antimicrobial properties of oral epithelial cells, through a strong induction of the expression of PLA2-IIA in a mechanism that involves activation of the Notch-1 receptor. Moreover, gingival expression of PLA2-IIA was significantly increased during initiation and progression of periodontal disease in non-human primates and interestingly, those PLA2-IIA expression changes were concurrent with oral dysbiosis. In this chapter, we present an innovative hypothesis of a potential mechanism involved in P. gingivalis-induced oral dysbiosis and inflammation based on our previous observations and a robust body of literature that supports the antimicrobial and proinflammatory properties of PLA2-IIA as well as its role in other chronic inflammatory diseases.


Assuntos
Disbiose , Doenças Periodontais , Porphyromonas gingivalis , Animais , Disbiose/microbiologia , Doenças Periodontais/enzimologia , Doenças Periodontais/microbiologia , Fosfolipases/genética , Poliésteres , Porphyromonas gingivalis/enzimologia , Porphyromonas gingivalis/genética
11.
Plant Mol Biol ; 101(6): 521-536, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549344

RESUMO

KEY MESSAGE: Castor patatin-like phospholipase A IIIß facilitates the exclusion of hydroxy fatty acids from phosphatidylcholine in developing transgenic Arabidopsis seeds. Hydroxy fatty acids (HFAs) are industrial useful, but their major natural source castor contains toxic components. Although expressing a castor OLEATE 12-HYDROXYLASE in Arabidopsis thaliana leads to the synthesis of HFAs in seeds, a high proportion of the HFAs are retained in phosphatidylcholine (PC). Thus, the liberation of HFA from PC seems to be critical for obtaining HFA-enriched seed oils. Plant phospholipase A (PLA) catalyzes the hydrolysis of PC to release fatty acyl chains that can be subsequently channeled into triacylglycerol (TAG) synthesis or other metabolic pathways. To further our knowledge regarding the function of PLAs from HFA-producing plant species, two class III patatin-like PLA cDNAs (pPLAIIIß or pPLAIIIδ) from castor or Physaria fendleri were overexpressed in a transgenic line of A. thaliana producing C18-HFA, respectively. Only the overexpression of RcpPLAIIIß resulted in a significant reduction in seed HFA content with concomitant changes in fatty acid composition. Reductions in HFA content occurred in both PC and TAG indicating that HFAs released from PC were not incorporated into TAG. These results suggest that RcpPLAIIIß may catalyze the removal of HFAs from PC in the developing seeds synthesizing these unusual fatty acids.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Ácidos Graxos/metabolismo , Fosfatidilcolinas/metabolismo , Fosfolipases/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética
12.
Proc Natl Acad Sci U S A ; 116(35): 17498-17508, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31413195

RESUMO

Transmission of Plasmodium falciparum involves a complex process that starts with the ingestion of gametocytes by female Anopheles mosquitoes during a blood meal. Activation of gametocytes in the mosquito midgut triggers "rounding up" followed by egress of both male and female gametes. Egress requires secretion of a perforin-like protein, PfPLP2, from intracellular vesicles to the periphery, which leads to destabilization of peripheral membranes. Male gametes also develop flagella, which assist in binding female gametes for fertilization. This process of gametogenesis, which is key to malaria transmission, involves extensive membrane remodeling as well as vesicular discharge. Phospholipase A2 enzymes (PLA2) are known to mediate membrane remodeling and vesicle secretion in diverse organisms. Here, we show that a P. falciparum patatin-like phospholipase (PfPATPL1) with PLA2 activity plays a key role in gametogenesis. Conditional deletion of the gene encoding PfPATPL1 does not affect P. falciparum blood stage growth or gametocyte development but reduces efficiency of rounding up, egress, and exflagellation of gametocytes following activation. Interestingly, deletion of the PfPATPL1 gene inhibits secretion of PfPLP2, reducing the efficiency of gamete egress. Deletion of PfPATPL1 also reduces the efficiency of oocyst formation in mosquitoes. These studies demonstrate that PfPATPL1 plays a role in gametogenesis, thereby identifying PLA2 phospholipases such as PfPATPL1 as potential targets for the development of drugs to block malaria transmission.


Assuntos
Gametogênese , Malária Falciparum/parasitologia , Malária Falciparum/transmissão , Fosfolipases/metabolismo , Plasmodium falciparum/fisiologia , Proteínas de Protozoários/metabolismo , Biologia Computacional/métodos , Humanos , Estágios do Ciclo de Vida , Fosfolipases/genética , Plasmodium falciparum/ultraestrutura , Proteínas de Protozoários/genética , Deleção de Sequência
13.
J Mycol Med ; 29(3): 201-209, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31378442

RESUMO

Candida albicans is a polymorphic opportunistic commensal that causes both superficial and systemic fungal infections especially in immunocompromised patients. Biologically synthesized silver nanoparticles (AgNPs) have emerged as potential antifungal agents. The present work evaluates the antifungal activity of Artemisia annua synthesized AgNPs against three Candida species (C. albicans ATCC 90028, C. tropicalis ATCC 750 and C. glabrata ATCC 90030). The in vitro effect of AgNPs was investigated for fungal growth, sterol content, secretion of hydrolytic enzymes and yeast-to-hyphal transition. The green synthesized AgNPs were effective against all the three species with minimum inhibitory concentration (MIC) in the range 80-120µgml-1. Candida glabrata showed greater sensitivity for AgNPs followed by Candida tropicalis and C. albicans. AgNPs at 4MIC were as effective as fluconazole (FLC) and caused only 5% haemolysis while FLC caused 50% haemolysis at the same concentration. The secretion of hydrolytic enzymes was the lowest in case of AgNP exposed C. glabrata. Yeast-to-hyphal transition was significantly reduced in treated C. albicans cells and showed disfigured morphology in SEM images. The decrease in ergosterol content was slightly higher (94%) in both C. glabrata and C. tropicalis in comparison to C. albicans (69%). Green synthesized AgNPs thus have immense potential as an antifungal and can play a crucial role in the management of Candida infections especially those caused by C. glabrata.


Assuntos
Antifúngicos/farmacologia , Artemisia annua/química , Candida/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/farmacologia , Candida/enzimologia , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida glabrata/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Fluconazol/farmacologia , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/metabolismo , Fosfolipases/metabolismo
14.
J Mycol Med ; 29(4): 325-330, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31447236

RESUMO

Candidemia is one of the most common fungal nosocomial infections worldwide. It causes high mortality and morbidity rate with significant hospital costs due to increased length of hospital stay and costs for anti-fungal treatment. This study aims to investigate anti-fungal drug susceptibility, enzymatic activity and biofilm formation of the Candida spp. isolated from blood cultures. In 2016, a total of 84 clinical Candida isolates were analyzed for minimum inhibitory concentration (MIC) against fluconazole and amphotericin B by agar diffusion E-test (E-strips). Three enzymatic activity tests for phospholipase, proteinase and esterase were performed by using egg yolk agar, bovine serum albumin medium and Tween 80 opacity medium, respectively. Biofilm formation was determined by crystal violet staining. To describing the various Candida distributions cultured, C. albicans was the most frequent species (n=37, 44.1%), followed by C. tropicalis (n=30, 35.7%), C. parapsilosis (n=8, 9.5%), C. glabrata (n=6, 7.1%) and C. guilliermondii (n=3, 3.6%). Regarding anti-fungal drug susceptibility, C. albicans was susceptible to fluconazole (100%). In addition, all clinical Candida isolates were fully susceptible to amphotericin B (100%). The predominant enzyme activity of C. albicans included medium to high levels of phospholipase, proteinase and esterase activities. C. tropicalis displayed esterase activity, while C. glabrata and C. guilliermondii had no phospholipase and proteinase activity. Non-albicans Candida (NAC) i.e. C. tropicalis formed a biofilm at a higher rate than C. albicans. This study revealed the production of virulent factors in Candida strains from candidemia patients.


Assuntos
Antifúngicos/farmacologia , Hemocultura , Candida/efeitos dos fármacos , Candida/patogenicidade , Candidemia/microbiologia , Biofilmes/crescimento & desenvolvimento , Candida/enzimologia , Infecção Hospitalar/microbiologia , Esterases/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/metabolismo , Fosfolipases/metabolismo , Fatores de Virulência
15.
Microbiology ; 165(11): 1203-1218, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31380737

RESUMO

Bacteria exist in polymicrobial environments and compete to prevail in a niche. The type VI secretion system (T6SS) is a nanomachine employed by Gram-negative bacteria to deliver effector proteins into target cells. Consequently, T6SS-positive bacteria produce a wealth of antibacterial effector proteins to promote their survival among a prokaryotic community. These toxins are loaded onto the VgrG-PAAR spike and Hcp tube of the T6SS apparatus and recent work has started to document the specificity of effectors for certain spike components. Pseudomonas aeruginosa encodes several PAAR proteins, whose roles have been poorly investigated. Here we describe a phospholipase family antibacterial effector immunity pair from Pseudomonas aeruginosa and demonstrate that a specific PAAR protein is necessary for the delivery of the effector and its cognate VgrG. Furthermore, the PAAR protein appears to restrict the delivery of other phospholipase effectors that utilise distinct VgrG proteins. We provide further evidence for competition for PAAR protein recruitment to the T6SS apparatus, which determines the identities of the delivered effectors.


Assuntos
Proteínas de Bactérias/metabolismo , Pseudomonas aeruginosa/metabolismo , Sistemas de Secreção Tipo VI/metabolismo , Sequência de Aminoácidos , Antibiose , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Periplasma/imunologia , Fosfolipases/química , Fosfolipases/genética , Fosfolipases/imunologia , Fosfolipases/metabolismo , Transporte Proteico , Pseudomonas aeruginosa/genética , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/imunologia
16.
J Neurol ; 266(11): 2657-2664, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31302745

RESUMO

Recessive mutations in DDHD2 cause SPG54, a complex hereditary spastic paraplegia (HSP) with less than forty patients reported worldwide. In this retrospective, multicenter study we describe eight additional SPG54 cases harboring homozygous or compound heterozygous DDHD2 variants. Finally, we reviewed literature data on SPG54, with the aim to better define the phenotype and the brain magnetic resonance imaging (MRI) pattern as well as genotype-phenotype correlations. SPG54 is typically characterized by early-onset (i.e., congenital or, more frequently, infantile) delay in motor and cognitive milestones, coupled or followed by appearance of spasticity. Cognitive impairment is absent in adult-onset cases. Spasticity progresses over time. Abnormal eye movement, found in about 50% of cases, is the feature most frequently associated with spasticity and developmental delay. Cerebellar ataxia is a prominent sign in several patients, including one adult of this study, suggesting to include SPG54 in the differential diagnosis of spastic-ataxia syndromes. Brain MRI shows thin corpus callosum and non-specific periventricular white matter lesions in about 90% and 70% of cases, respectively. Brain MR spectroscopy reveals abnormal lipid peak in 90% of investigated patients. Twenty-one pathogenic changes have been reported so far, many of which are nonsense or small deletion/duplication. Most mutations appear to be private, with only two mutations recurring in three (i.e., R287*) or more families (i.e., D660H). The identification of nine novel variants expands the molecular spectrum of DDHD2-related HSP and corroborates the notion of a quite homogeneous clinical and neuroradiological phenotype in spite of different genotypes.


Assuntos
Fosfolipases/genética , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/patologia , Adolescente , Encéfalo/patologia , Criança , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Paraplegia Espástica Hereditária/fisiopatologia , Adulto Jovem
17.
Biomed Res Int ; 2019: 1851740, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275963

RESUMO

The human opportunistic fungal pathogen Candida albicans causes a severe health burden while the biofilms formed by C. albicans present a kind of infections that are hard to cure, highlighting the pressing need for new antifungal drugs against C. albicans. This study was to explore the antifungal activities of lycorine hydrochloride (LH) against C. albicans. The minimal inhibitory concentration (MIC) of LH against C. albicans SC5314 was 64 µM. Below its MIC, LH demonstrated antivirulence property by suppressing adhesion, filamentation, biofilm formation, and development, as well as the production of extracellular phospholipase and exopolymeric substances (EPS). The cytotoxicity of LH against mammalian cells was low, with half maximal inhibitory concentrations (IC50) above 256 µM. Moreover, LH showed a synergistic effect with AmB, although its interaction with fluconazole, as well as caspofungin, was indifferent. Thus, our study reports the potential use of LH, alone or in combination with current antifungal drugs, to fight C. albicans infections.


Assuntos
Alcaloides de Amaryllidaceae/farmacologia , Candida albicans/patogenicidade , Fenantridinas/farmacologia , Adesividade/efeitos dos fármacos , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/toxicidade , Antifúngicos/química , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Morte Celular/efeitos dos fármacos , AMP Cíclico/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Hifas/efeitos dos fármacos , Fenantridinas/química , Fenantridinas/toxicidade , Fosfolipases/metabolismo , Virulência/efeitos dos fármacos
18.
Arch Microbiol ; 201(8): 1147-1149, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31147748

RESUMO

Non-albicans Candida species have acquired relevance in the last decades as a cause of serious disease. The virulence factors and antifungal susceptibility of these rare pathogens remain largely unrecognized. We examined a total of 50 yeast isolates corresponding to 11 different infrequently isolated yeast species for their in vitro enzymatic profile and susceptibility pattern as first-line antifungals. We found aspartyl protease activity for 100% of the isolates tested as well as variable DNAse, hemolysin, phospholipase and esterase activities. All strains had low MICs for amphotericin B and showed a variable response to fluconazole (0.125-32 µg/mL) and the echinocandins tested (0.25-> 8 µg/mL).


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/genética , Equinocandinas/farmacologia , Fluconazol/farmacologia , Ácido Aspártico Proteases/genética , Candida/classificação , Candida/isolamento & purificação , Desoxirribonucleases/genética , Esterases/genética , Proteínas Hemolisinas/genética , Humanos , Testes de Sensibilidade Microbiana , Fosfolipases/genética , Fatores de Virulência , Leveduras/classificação , Leveduras/efeitos dos fármacos , Leveduras/isolamento & purificação
19.
Appl Biochem Biotechnol ; 189(3): 903-918, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31144254

RESUMO

Interfacial esterases are useful enzymes in bioconversion and racemic mixture resolution processes. Marine invertebrates are few explored potential sources of these proteins. In this work, aqueous extracts of 41 species of marine invertebrates were screened for esterase, lipase, and phospholipase A activities, being all positive. Five extracts (Stichodactyla helianthus, Condylactis gigantea, Stylocheilus longicauda, Zoanthus pulchellus, and Plexaura homomalla) were selected for their activity values and immobilized on Octyl-Sepharose CL 4B support by interfacial adsorption. The selectivity of this immobilization method for interfacial esterases was evidenced by immobilization percentages ≥ 94% in almost all cases for lipase and phospholipase A activities. Six pharmaceutical-relevant esters (phenylethyl butyrate, ethyl-2-hydroxy-4-phenyl-butanoate, 2-oxyranylmethyl acetate (glycidol acetate), 7-aminocephalosporanic acid, methyl-prostaglandin F2α, and methyl-6-metoxy-α-methyl-2-naphtalen-acetate -naproxen methyl ester-) were bioconverted by at least three of these biocatalysts, with the lowest conversion percentage of 24%. In addition, three biocatalysts were used in the racemic mixture resolution of three previous compounds. The S. helianthus-derived biocatalyst showed the highest enantiomeric ratios for glycidol acetate (2.67, (S)-selective) and naproxen methyl ester (8.32, (R)-selective), and the immobilized extract of S. longicauda was the most resolutive toward the ethyl-2-hydroxy-4-phenyl-butanoate (8.13, (S)-selective). These results indicate the relevance of such marine interfacial esterases as immobilized biocatalysts for the pharmaceutical industry.


Assuntos
Organismos Aquáticos/enzimologia , Biocatálise , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Esterases/química , Esterases/metabolismo , Invertebrados/enzimologia , Animais , Ésteres/química , Ésteres/metabolismo , Lipase/metabolismo , Fosfolipases/metabolismo , Estereoisomerismo , Especificidade por Substrato , Água/química
20.
Ophthalmic Genet ; 40(3): 267-275, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31135245

RESUMO

Purpose: To confirm the pathogenic role of a novel mutation in PNPLA6 and detail the phenotype of a patient presenting with choroideremia-like chorioretinal degeneration. Methods: A 40-year-old man with presumed choroideremia underwent a complete ophthalmic examination, full-field electroretinography (ERG), kinetic fields and two-color automated static perimetry and retinal imaging with spectral domain optical coherence tomography (SD-OCT) and near-infrared (NIR) and short wavelength (SW) fundus autofluorescence (FAF). Results: Visual acuity was 20/200 and 20/40 for the right and left eye, respectively, with a ~ 5D myopic correction. Small cone-mediated ERG responses were detectable. The visual field by kinetic perimetry (V-4e stimulus) was limited to small (<5°) central islands separated from large peripheral islands of vision by an absolute midperipheral scotoma. There were minute islands of apparently spared retina near the foveal center separated from large peripheral islands of better appearing retina by severe pericentral and midperipheral chorioretinal atrophy. SD-OCT confirmed detectable photoreceptors near the center and in nasal midperipheral retina despite severe outer segment loss. Central photoreceptor loss was associated with disproportionately severe retinal pigment epithelium (RPE) depigmentation and choroidal atrophy. NIR- and SW-autofluorescence was widely hypoautofluorescent with the exception of residual autofluorescence along peripheral regions of relative RPE preservation. Gene screening revealed biallelic mutations (p.Arg1031GlnfsTer38/p.Arg1183Gln) in PNPLA6. Hypogonadotropic hypogonadism and cerebellar vermis hypoplasia by MRI confirmed a diagnosis of Boucher-Neuhäuser syndrome. Conclusions: PNPLA6-associated retinal degenerations can present with predominantly retinal findings and subtle systemic abnormalities and should be considered in the differential diagnosis of diffuse chorioretinal atrophies.


Assuntos
Coroideremia/diagnóstico , Hipogonadismo/diagnóstico , Mutação , Fosfolipases/genética , Distrofias Retinianas/diagnóstico , Ataxias Espinocerebelares/diagnóstico , Adulto , Coroideremia/genética , Diagnóstico Diferencial , Humanos , Hipogonadismo/genética , Masculino , Fenótipo , Prognóstico , Distrofias Retinianas/genética , Ataxias Espinocerebelares/genética , Acuidade Visual
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