RESUMO
Proteases are enzymes that hydrolyze peptide bonds present in proteins and peptides. They are widely used for various industrial applications, such as in the detergent, food, and dairy industries. Cheese is one of the most important products of the dairy industry, and the coagulation stage is crucial during the cheese-making process. Enzymatic coagulation is the most common technique utilized for this purpose. Microbial enzymes are frequently used for coagulation due to their advantages in terms of availability, sustainability, quality control, product variety, and compliance with dietary and cultural/religious requirements. In the present study, we identified and subsequently characterized milk coagulant activity from the fungus Pleurotus djamor PLO13, obtained during a solid-state fermentation process, using the agro-industrial residue, wheat bran, as the fermentation medium. Maximum enzyme production and caseinolytic activity occurred 120 h after cultivation. When the enzyme activity against various protease-specific synthetic substrates and inhibitors was analyzed, the enzyme was found to be a serine protease, similar to elastase 2. This elastase-2-like serine protease was able to coagulate pasteurized whole and reconstituted skim milk highly efficiently in the presence and absence of calcium, even at room temperature. The coagulation process was influenced by factors such as temperature, time, and calcium concentration. We demonstrate here, for the first time, an elastase-2-like enzyme in a microorganism and its potential application in the food industry for cheese production.
RESUMO
Mannheimiahaemolytica is an opportunistic agent of the respiratory tract of bovines, a member of the Pasteurellaceae family, and the causal agent of fibrinous pleuropneumonia. This bacterium possesses different virulence factors, allowing it to colonize and infect its host. The present work describes the isolation and characterization of a serine protease secreted by M. haemolytica serotype 1. This protease was isolated from M. haemolytica cultured media by precipitation with 50 % methanol and ion exchange chromatography on DEAE-cellulose. It is a 70-kDa protease able to degrade sheep and bovine fibrinogen or porcine gelatin but not bovine IgG, hemoglobin, or casein. Mass spectrometric analysis indicates its identity with protease IV of M. haemolytica. The proteolytic activity was active between pH 5 and 9, with an optimal pH of 8. It was stable at 50 °C for 10 min but inactivated at 60 °C. The sera of bovines with chronic or acute pneumonia recognized this protease. Still, it showed no cross-reactivity with rabbit hyperimmune serum against the secreted metalloprotease from Actinobacilluspleuropneumoniae, another member of the Pasteurellaceae family. M. haemolytica secreted proteases could contribute to the pathogenesis of this bacterium through fibrinogen degradation, a characteristic of this fibrinous pleuropneumonia.
Assuntos
Fibrinogênio , Mannheimia haemolytica , Serina Proteases , Animais , Mannheimia haemolytica/enzimologia , Ovinos , Bovinos , Fibrinogênio/metabolismo , Concentração de Íons de Hidrogênio , Serina Proteases/metabolismo , Serina Proteases/isolamento & purificação , Temperatura , Proteólise , Peso Molecular , Gelatina/metabolismo , Estabilidade Enzimática , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/isolamento & purificação , Espectrometria de Massas , Cromatografia por Troca Iônica , Suínos , Fatores de Virulência/metabolismo , Fatores de Virulência/isolamento & purificaçãoRESUMO
The peptide derived from E. contortisiliquum trypsin inhibitor (Pep-3-EcTI), peptide derived from kallikrein inhibitor isolated from B. bauhinioides (Pep-BbKI), and B. rufa peptide modified from B. bauhinioides (Pep-BrTI) peptides exhibit anti-inflammatory and antioxidant activities, suggesting their potential for treating asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO). We compared the effects of these peptides with dexamethasone (DX) treatment in an ACO model. In this study, 11 groups of male BALB/c mice were pre-treated under different conditions, including sensitization with intraperitoneal injection and inhalation of ovalbumin (OVA), intratracheal instillation of porcine pancreatic elastase (ELA), sensitization with intraperitoneal injection, and various combinations of peptide treatments with Pep-3-EcTI, Pep-BbKI, Pep-BrTI, dexamethasone, and non-treated controls (SAL-saline). Respiratory system resistance, airway resistance, lung tissue resistance, exhaled nitric oxide, linear mean intercept, immune cell counts in the bronchoalveolar lavage fluid, cytokine expression, extracellular matrix remodeling, and oxidative stress in the airways and alveolar septa were evaluated on day 28. Results showed increased respiratory parameters, inflammatory markers, and tissue remodeling in the ACO group compared to controls. Treatment with the peptides or DX attenuated or reversed these responses, with the peptides showing effectiveness in controlling hyperresponsiveness, inflammation, remodeling, and oxidative stress markers. These peptides demonstrated an efficacy comparable to that of corticosteroids in the ACO model. However, this study highlights the need for further research to assess their safety, mechanisms of action, and potential translation to clinical studies before considering these peptides for human use.
RESUMO
Typical Kunitz proteins (I2 family of the MEROPS database, Kunitz-A family) are metazoan competitive inhibitors of serine peptidases that form tight complexes of 1:1 stoichiometry, mimicking substrates. The cestode Echinococcus granulosus, the dog tapeworm causing cystic echinococcosis in humans and livestock, encodes an expanded family of monodomain Kunitz proteins, some of which are secreted to the dog host interface. The Kunitz protein EgKU-7 contains, in addition to the Kunitz domain with the anti-peptidase loop comprising a critical arginine, a C-terminal extension of â¼20 amino acids. Kinetic, electrophoretic, and mass spectrometry studies using EgKU-7, a C-terminally truncated variant, and a mutant in which the critical arginine was substituted by alanine, show that EgKU-7 is a tight inhibitor of bovine and canine trypsins with the unusual property of possessing two instead of one site of interaction with the peptidases. One site resides in the anti-peptidase loop and is partially hydrolyzed by bovine but not canine trypsins, suggesting specificity for the target enzymes. The other site is located in the C-terminal extension. This extension can be hydrolyzed in a particular arginine by cationic bovine and canine trypsins but not by anionic canine trypsin. This is the first time to our knowledge that a monodomain Kunitz-A protein is reported to have two interaction sites with its target. Considering that putative orthologs of EgKU-7 are present in other cestodes, our finding unveils a novel piece in the repertoire of peptidase-inhibitor interactions and adds new notes to the evolutionary host-parasite concerto.
Assuntos
Echinococcus granulosus , Proteínas de Helminto , Echinococcus granulosus/enzimologia , Echinococcus granulosus/genética , Echinococcus granulosus/metabolismo , Animais , Cães , Proteínas de Helminto/metabolismo , Proteínas de Helminto/genética , Proteínas de Helminto/química , Inibidores da Tripsina/metabolismo , Inibidores da Tripsina/química , Bovinos , Sequência de Aminoácidos , Tripsina/química , Tripsina/metabolismoRESUMO
Trypanosoma cruzi is the causative agent of Chagas disease, a chronic pathology that affects the heart and/or digestive system. This parasite invades and multiplies in virtually all nucleated cells, using a variety of host cell receptors for infection. T. cruzi has a gene that encodes an ecotin-like inhibitor of serine peptidases, ISP2. We generated ISP2-null mutants (Δisp2) in T. cruzi Dm28c using CRISPR/Cas9. Epimastigotes of Δisp2 grew normally in vitro but were more susceptible to lysis by human serum compared to parental and ISP2 add-back lines. Tissue culture trypomastigotes of Δisp2 were more infective to human muscle cells in vitro, which was reverted by the serine peptidase inhibitors aprotinin and camostat, suggesting that host cell epitheliasin/TMPRSS2 is the target of ISP2. Pretreatment of host cells with an antagonist to the protease-activated receptor 2 (PAR2) or an inhibitor of Toll-like receptor 4 (TLR4) selectively counteracted the increased cell invasion by Δisp2, but did not affect invasion by parental and add-back lines. The same was observed following targeted gene silencing of PAR2, TLR4 or TMPRSS2 in host cells by siRNA. Furthermore, Δisp2 caused increased tissue edema in a BALB/c mouse footpad infection model after 3 h differently to that observed following infection with parental and add-back lines. We propose that ISP2 contributes to protect T. cruzi from the anti-microbial effects of human serum and to prevent triggering of PAR2 and TLR4 in host cells, resulting in the modulation of host cell invasion and contributing to decrease inflammation during acute infection.
Assuntos
Doença de Chagas , Trypanosoma cruzi , Animais , Camundongos , Humanos , Receptor 4 Toll-Like/genética , Receptor PAR-2/genética , Doença de Chagas/genética , Doença de Chagas/parasitologia , Antivirais/farmacologia , Inibidores de Serina Proteinase/farmacologia , Inflamação , Serina , Serina Endopeptidases/genéticaRESUMO
Rhamnolipids (RHLs) are promising biosurfactants with important applications in several industrial segments. These compounds are produced through biotechnological processes using the bacteria Pseudomonas Aeruginosa. The main methods of analyzing this compound are based on chromatographic techniques. In this study, an electrochemical sensor based on a platform modified with reduced graphene oxide, manganese nanoparticles covered with a molecularly imprinted poly (L-Ser) film was used as an alternative method to quantify RHL through its hydrolysis product, acid 3-hydroxydecanoic acid (3-HDA). The proposed sensor was characterized microscopically, spectroscopically and electrochemically. Under optimized experimental conditions, an analytical curve was obtained in the linear concentration range from 2.0 × 10-12 mol L-1 to 1.0 × 10-10 mol L-1. The values estimated of LOD, LOQ and AS were 8.3 × 10-13 mol L-1, 2.7 × 10-12 mol L-1and 1.3 × 107 A L mol-1, respectively. GCE/rGO/MnNPs/L-Ser@MIP exhibits excellent selectivity, repeatability, and high stability for the detection of 3-HDA. Furthermore, the developed method was successfully applied to the recognition of the hydrolysis product (3-HDA) of RHLs obtained from guava agro-waste. Statistical comparison between GCE/rGO/MnNPs/L-Ser@MIP and HPLC method confirms the accuracy of the electrochemical sensor within a 95% confidence interval.
Assuntos
Glicolipídeos , Grafite , Impressão Molecular , Nanopartículas , Manganês , Polímeros/química , Limite de Detecção , Grafite/química , Nanopartículas/química , Técnicas Eletroquímicas/métodos , Impressão Molecular/métodos , EletrodosRESUMO
A novel trypsin inhibitor from Cajanus cajan (TIC) fresh leaves was partially purified by affinity chromatography. SDS-PAGE revealed one band with about 15 kDa with expressive trypsin inhibitor activity by zymography. TIC showed high affinity for trypsin (Ki = 1.617 µM) and was a competitive inhibitor for this serine protease. TIC activity was maintained after 24 h of treatment at 70 °C, after 1 h treatments with different pH values, and ß-mercaptoethanol increasing concentrations, and demonstrated expressive structural stability. However, the activity of TIC was affected in the presence of oxidizing agents. In order to study the effect of TIC on secreted serine proteases, as well as on the cell culture growth curve, SK-MEL-28 metastatic human melanoma cell line and CaCo-2 colon adenocarcinoma was grown in supplemented DMEM, and the extracellular fractions were submitted salting out and affinity chromatography to obtain new secreted serine proteases. TIC inhibited almost completely, 96 to 89%, the activity of these serine proteases and reduced the melanoma and colon adenocarcinoma cells growth of 48 and 77% respectively. Besides, it is the first time that a trypsin inhibitor was isolated and characterized from C. cajan leaves and cancer serine proteases were isolated and partial characterized from SK-MEL-28 and CaCo-2 cancer cell lines. Furthermore, TIC shown to be potent inhibitor of tumor protease affecting cell growth, and can be one potential drug candidate to be employed in chemotherapy of melanoma and colon adenocarcinoma.
Assuntos
Cajanus , Folhas de Planta , Humanos , Cajanus/química , Folhas de Planta/química , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidores da Tripsina/farmacologia , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificação , Proteínas de Plantas/farmacologia , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Serina Proteases/química , Serina Proteases/isolamento & purificação , Serina Proteases/metabolismoRESUMO
Colletotrichum graminicola, the causal agent of maize leaf anthracnose and stalk rot, differentiates a pressurized infection cell called an appressorium in order to invade the epidermal cell, and subsequently forms biotrophic and necrotrophic hyphae to colonize the host tissue. While the role of force in appressorial penetration is established (Bechinger et al., 1999), the involvement of cell wall-degrading enzymes (CWDEs) in this process and in tissue colonization is poorly understood, due to the enormous number and functional redundancy of these enzymes. The serine/threonine protein kinase gene SNF1 identified in Sucrose Non-Fermenting yeast mutants mediates de-repression of catabolite-repressed genes, including many genes encoding CWDEs. In this study, we identified and functionally characterized the SNF1 homolog of C. graminicola. Δsnf1 mutants showed reduced vegetative growth and asexual sporulation rates on media containing polymeric carbon sources. Microscopy revealed reduced efficacies in appressorial penetration of cuticle and epidermal cell wall, and formation of unusual medusa-like biotrophic hyphae by Δsnf1 mutants. Severe and moderate virulence reductions were observed on intact and wounded leaves, respectively. Employing RNA-sequencing we show for the first time that more than 2,500 genes are directly or indirectly controlled by Snf1 in necrotrophic hyphae of a plant pathogenic fungus, many of which encode xylan- and cellulose-degrading enzymes. The data presented show that Snf1 is a global regulator of gene expression and is required for full virulence.
Assuntos
Colletotrichum , Zea mays , Zea mays/genética , Virulência/genética , Parede Celular/genética , Parede Celular/metabolismo , Saccharomyces cerevisiae/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Doenças das Plantas/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismoRESUMO
The use of various herbs and their compounds has been a strategy widely used in the fight against various human diseases. For example, rosmarinic acid, a bioactive phenolic compound commonly found in Rosemary plants (Rosmarinus officinalis Labiatae), has multiple therapeutic benefits in different diseases, such as cancer. Therefore, the study aimed to evaluate in silico and in vitro the inhibition potential of the enzyme Elastase from the porcine pancreas by rosmarinic acid isolated from the plant species R. officinalis Linn. Through Molecular Docking, the mechanism of action was investigated. In addition, rosmarinic acid presented a range of 5-60 µg/mL and significantly inhibited Elastase. At 60 µg/mL, there was an inhibition of 55% on the enzymatic activity. The results demonstrate the inhibition of Elastase by rosmarinic acid, which can lead to the development of new enzyme inhibitors that can be an inspiration for developing various drugs, including anticancer drugs.
Assuntos
Ácido Rosmarínico , Rosmarinus , Humanos , Elastase Pancreática , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Cinamatos/farmacologia , Depsídeos/farmacologiaRESUMO
The aims of this study are to characterize the antiplatelet activity of StSBTc-3, a potato serine protease with fibrino (geno) lytic activity, and to provide information on its mechanism of action. The results obtained show that StSBTc-3 inhibits clot retraction and prevents platelet aggregation induced by thrombin, convulxin, and A23187. Platelet aggregation inhibition occurs in a dose-dependent manner and is not affected by inactivation of StSBTc-3 with the inhibitor of serine proteases phenylmethylsulfonyl fluoride (PMSF). In addition, StSBTc-3 reduces fibrinogen binding onto platelets. In-silico calculations show a high binding affinity between StSBTc-3 and human α2bß3 integrin suggesting that the antiplatelet activity of StSBTc-3 could be associated with the fibronectin type III domain present in its amino acid sequence. Binding experiments show that StSBTc-3 binds to α2bß3 preventing the interaction between α2bß3 and fibrinogen and, consequently, inhibiting platelet aggregation. StSBTc-3 represents a promising compound to be considered as an alternative to commercially available drugs used in cardiovascular therapies.
Assuntos
Solanum tuberosum , Humanos , Serina/metabolismo , Plaquetas/metabolismo , Agregação Plaquetária , Serina Endopeptidases/metabolismo , Fibrinogênio/metabolismo , Subtilisinas/metabolismoRESUMO
BACKGROUND Leishmania (Viannia) braziliensis Thor strain exhibits a heterogeneous composition comprised of subpopulations with varying levels of infectivity. Clonal subpopulations were previously obtained from the strain Thor by sorting single-parasites and proceeding cultivation. The subpopulations used in this study are named Thor03, Thor 10 and Thor22. OBJECTIVES Phenotypic characteristics of the parasite, specially focusing on virulence factors and resistance to the antimicrobial mechanisms of macrophages, were investigate in these subpopulations. METHODS Cellular and molecular biology, as well as biochemistry approaches were applied to obtain the data analysed in this study. FINDINGS Relative quantification of gene expression was measured for calpain, cysteine protease B (CPB), and subtilisin proteases but no significant differences in these genes' expression among subpopulations was observed. However, subtilisin and CPB proteins were assessed as more abundant in Thor03 by fluorescence-labelled flow cytometry technique. Western Blotting assays, as semi-quantitative analysis in gel, showed higher concentrations of subtilisin (110 to 50 kDa) and CPB (40 to 18 kDa) in extract of intracellular amastigotes from subpopulations Thor03 and Thor10 and calpain (60 to 25 kDa) showed no significant differences among subpopulations. Complementary, higher trypanothione reductase activity was observed in Thor10 intracellular amastigotes and assays of susceptibility to hydrogen peroxide-inducing agents and nitric oxide donors conducted with promastigotes revealed greater resistance to in vitro oxidative stress induction for Thor10, followed by Thor03. MAIN CONCLUSIONS The data obtained for the virulence factors explored here suggest how multiple coexisting phenotypic-distinct subpopulations may contribute in adaptability of a single L. (V.) braziliensis strain during infection in the host cells.
RESUMO
Introducción. Los síndromes de sobrecrecimiento corporal segmentario son un grupo de enfermedades poco frecuentes caracterizadas por exceso de crecimiento en una o más partes del cuerpo relacionadas, en su mayoría, con mutaciones en mosaico en la vía de señalización AKT/PI3K/mTOR y RAS-MAPK. Nuestro objetivo fue analizar las características clínicas y auxológicas, y la calidad de vida relacionada a salud (CVRS) en este grupo de pacientes en un hospital de tercer nivel de atención. Población y métodos. Estudio transversal de una cohorte en seguimiento. Se analizaron edad, sexo, datos sociodemográficos, mediciones antropométricas del segmento afectado y del contralateral, complicaciones, tratamiento, calidad de vida (PedsQL4.0) y dolor. Se calcularon medidas centrales y de dispersión. Se realizó análisis univariado entre calidad de vida y variables incluidas. Resultados. Se incluyeron 50 pacientes, 29 varones. Mediana de edad 9,95 (r 1,44-17,81) años. El diagnóstico más frecuente fue síndrome de sobrecrecimiento relacionado a PIK3CA (PROS) (37/50). Mediana de número de segmentos afectados 2 (r: 1-7) por niño. Cuarenta casos presentaron malformación vascular; 20, capilar. El dolor (24/50) fue la complicación más frecuente. Treinta y un pacientes mostraron asimetría de longitud de miembros inferiores, < 5 cm. La estatura se ubicó entre los centilos 50 y 97 en la mayoría de los niños. Menor CVRS se observó en mujeres, en pacientes con malformación vascular compleja y necesidades básicas insatisfechas (NBI). Conclusiones. PROS fue el diagnóstico más frecuente. El dolor fue una complicación frecuente. La CVRS fue menor en mujeres, pacientes con malformación vascular combinada y NBI.
Introduction. Segmental overgrowth syndromes are a group of rare diseases characterized by overgrowth in one or more parts of the body, mostly related to mosaic mutations in the AKT/PI3K/mTOR and RASMAPK signaling pathway. Our objective was to analyze the clinical and auxological characteristics and health-related quality of life (HRQoL) in this group of patients at a tertiary care hospital. Population and methods. Cross-sectional study of a follow-up cohort. Age, sex, sociodemographic data, anthropometric measurements of the affected and contralateral segments, complications, treatment, quality of life (PedsQL 4.0), and pain were analyzed. Central and dispersion measures were estimated. A univariate analysis between the quality of life and study variables was done. Results. A total of 50 patients were included; 29 were males. Median age: 9.95 (r: 1.4417.81) years. The most common diagnosis was PIK3CA-related overgrowth spectrum (PROS) (37/50). The median number of affected segments was 2 (r: 17) per patient. Vascular malformations were observed in 40, and capillary malformations, in 20 patients. Pain was the most common complication (24/50). An asymmetry of the lower extremities of < 5 cm was observed in 31 patients. In most children, height was between the 50th and 97th percentiles. A lower HRQoL was observed among girls, patients with complex vascular malformations, and those with unmet basic needs (UBNs). Conclusions. PROS was the most common diagnosis. Pain was the most common complication. HRQoL was lower among girls, patients with combined vascular malformations, and those with UBNs.
Assuntos
Humanos , Pré-Escolar , Criança , Adolescente , Qualidade de Vida , Malformações Vasculares , Dor , Síndrome , Transdução de Sinais , Estudos Transversais , MutaçãoRESUMO
Antifungal resistance poses a significant challenge to disease management, necessitating the development of novel drugs. Antimicrobial peptides offer potential solutions. This study focused on extraction and characterization of peptides from Adenanthera pavonina seeds with activity against Candida species, Mycobacterium tuberculosis, proteases, and α-amylases. Peptides were extracted in phosphate buffer and heated at 90°C for 10 min to create a peptide rich heated fraction (PRHF). After confirming antimicrobial activity and the presence of peptides, the PRHF underwent ion exchange chromatography, yielding retained and non-retained fractions. These fractions were evaluated for antimicrobial activity and cytotoxicity against murine macrophages. The least toxic and most active fraction underwent reversed-phase chromatography, resulting in ten fractions. These fractions were tested for peptides and antimicrobial activity. The most active fraction was rechromatographed on a reversed-phase column, resulting in two fractions that were assessed for antimicrobial activity. The most active fraction revealed a single band of approximately 6 kDa and was tested for inhibitory effects on proteases and α-amylases. Thermal stability experiments were conducted on the 6 kDa peptide at different temperatures followed by reassessment of antifungal activity and circular dichroism. The 6 kDa peptide inhibited yeasts, M. tuberculosis, human salivary and Tenebrio molitor larvae intestine α-amylases, and proteolytic activity from fungal extracts, and thus named ApPI. Remarkably, ApPI retained antifungal activity and conformation after heating and is primarily composed of α-helices. ApPI is a thermally stable serine protease/α-amylase inhibitor from A. pavonina seeds, offering promise as a foundational molecule for innovative therapeutic agents against fungal infections and tuberculosis.
RESUMO
Objective: The current study's objective is to characterize a new throm-bin-like enzyme called TLBro that was obtained from Bothrops roedingeris snake from a biochemical and hemostatic perspective. Methodology: One chromatographic step was used to purify it, producing the serine protease TLBro. Molecular mass was estimated by SDS-PAGE to be between reduced and unreduced by 35 kDa. Tryptic peptide sequencing using Swiss Prot provided the complete amino acid sequence. Expasy.org by conducting a search that is limited to Crotalinae snake serine proteases and displaying a high degree of amino acid sequence. Results: Ser (182) is inhibited by phenylmethylsulfonyl fluoride (PMSF), and TLBro demonstrated the presence of Asp (88) residues. It also deduced the positions of His (43) and Ser (182) in the set of three coordinated amino acids in serine proteases. It was discovered that this substrate had high specificity for BANA, Michaelis-Menten behavior with KM 0 point85 mM and Vmax 1 point89 nmoles -NA/L/min, and high stability between temperatures (15 to 70°C) and pHs (2 point0 to 10 point0). According to doses and incubation times, TLBro degraded fibrin preferentially on the B-chain; additionally, its activities were significantly diminished after preincubation with divalent ions (Zn2 and Cd2). When incubated with PMSF, a particular serine protease inhibitor, enzymatic activities and platelet aggregation were inhibited. Conclusion: The findings revealed distinct structural and functional differences between the serine proteases, adding to the information and assisting in the improvement of the structure-function relationship.
RESUMO
PURPOSE: Offer a personal perspective on the scientific advances on macular telangiectasia type 2 (MacTel2) since the launch of the MacTel Project in 2005. DESIGN: Literature review and personal perspective. METHODS: Critical review of the peer-reviewed literature and personal perspective. RESULTS: Generous financial support from the Lowy Medical Research Institute laid the foundations of the MacTel Project. MacTel Project investigators used state of the art multimodal retinal imaging and advanced modern biological methods to unravel many of the mysteries surrounding MacTel2. Major accomplishments includes elucidation of the pathogenic role that low serine levels, elevated 1-deoxysphingolipids and other mechanisms induce mitochondrial dysfunction which lead to Müller cell and photoreceptor degeneration; the use of objective measures of retinal structures such as the area of ellipsoid zone disruption as an outcome measure in clinical trials; the demonstration that the ciliary neurotrophic factor slows down retinal degeneration and the development of a new severity scale classification based on multimodal imaging findings. CONCLUSIONS: MacTel2 is a predominantly metabolic disease characterized by defects in energy metabolism. Despite relatively good visual acuities, MacTel2 patients experience significant visual disability. The Mac Tel Project has been instrumental in advancing MacTel2 knowledge in the past two decades.
RESUMO
Toehold switches are biosensors useful for the detection of endogenous and environmental RNAs. They have been successfully engineered to detect virus RNAs in cell-free gene expression reactions. Their inherent sequence programmability makes engineering a fast and predictable process. Despite improvements in the design, toehold switches suffer from leaky translation in the OFF state, which compromises the fold change and sensitivity of the biosensor. To address this, we constructed and tested signal amplification circuits for three toehold switches triggered by Dengue and SARS-CoV-2 RNAs and an artificial RNA. The serine integrase circuit efficiently contained leakage, boosted the expression fold change from OFF to ON, and decreased the detection limit of the switches by 3-4 orders of magnitude. Ultimately, the integrase circuit converted the analog switches' signals into digital-like output. The circuit is broadly useful for biosensors and eliminates the hard work of designing and testing multiple switches to find the best possible performer.
Assuntos
Técnicas Biossensoriais , COVID-19 , Humanos , SARS-CoV-2/genética , RNA , IntegrasesRESUMO
Sea anemones are known to produce a diverse array of toxins with different cysteine-rich peptide scaffolds in their venoms. The serine peptidase inhibitors, specifically Kunitz inhibitors, are an important toxin family that is believed to function as defensive peptides, as well as prevent proteolysis of other secreted anemone toxins. In this study, we isolated three serine peptidase inhibitors named Anthopleura cascaia peptide inhibitors I, II, and III (ACPI-I, ACPI-II, and ACPI-III) from the venom of the endemic Brazilian sea anemone A. cascaia. The venom was fractionated using RP-HPLC, and the inhibitory activity of these fractions against trypsin was determined and found to range from 59% to 93%. The spatial distribution of the anemone peptides throughout A. cascaia was observed using mass spectrometry imaging. The inhibitory peptides were found to be present in the tentacles, pedal disc, and mesenterial filaments. We suggest that the three inhibitors observed during this study belong to the venom Kunitz toxin family on the basis of their similarity to PI-actitoxin-aeq3a-like and the identification of amino acid residues that correspond to a serine peptidase binding site. Our findings expand our understanding of the diversity of toxins present in sea anemone venom and shed light on their potential role in protecting other venom components from proteolysis.
RESUMO
Extracellular proteases from halophilic archaea displays increased enzymatic activities in hypersaline environment. In this study, an extracellular protease-coding gene, hly34, from the haloarchaeal strain Halococcus salifodinae PRR34, was obtained through homologous search. The protease activity produced by this strain at 20% NaCl, 42 °C, and pH 7.0 was 32.5 ± 0.5 (U·mL-1). The codon-optimized hly34 which is specific for Escherichia coli can be expressed in E. coli instead of native hly34. It exhibits proteolytic activity under a wide range of low- or high-salt concentrations, slightly acidic or alkaline conditions, and slightly higher temperatures. The Hly34 presented the highest proteolytic activity at 50 °C, pH 9.0, and 0-1 M NaCl. It was found that the Hly34 showed a higher enzyme activity under low-salt conditions. Hly34 has good stability at different NaCl concentrations (1-4 M) and pH (6.0-10.0), as well as good tolerance to some metal ions. However, at 60 °C, the stability is reduced. It has a good tolerance to some metal ions. The proteolytic activity was completely inhibited by phenylmethanesulfonyl fluoride, suggesting that the Hly34 is a serine protease. This study further deepens our understanding of haloarchaeal extracellular protease, most of which found in halophilic archaea are classified as serine proteases. These proteases exhibit a certain level of alkaline resistance and moderate heat resistance, and they may emerge with higher activity under low-salt conditions than high-salt conditions. The protease Hly34 is capable of degrading a number of proteins, including substrate proteins, such as azocasein, whey protein and casein. It has promising applications in industrial production.
Assuntos
Halococcus , Halococcus/genética , Halococcus/metabolismo , Cloreto de Sódio/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Serina Proteases , Serina Endopeptidases , Metais , Íons , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , TemperaturaRESUMO
Introduction. Segmental overgrowth syndromes are a group of rare diseases characterized by overgrowth in one or more parts of the body, mostly related to mosaic mutations in the AKT/PI3K/mTOR and RAS- MAPK signaling pathway. Our objective was to analyze the clinical and auxological characteristics and health-related quality of life (HRQoL) in this group of patients at a tertiary care hospital. Population and methods. Cross-sectional study of a follow-up cohort. Age, sex, sociodemographic data, anthropometric measurements of the affected and contralateral segments, complications, treatment, quality of life (PedsQL 4.0), and pain were analyzed. Central and dispersion measures were estimated. A univariate analysis between the quality of life and study variables was done. Results. A total of 50 patients were included; 29 were males. Median age: 9.95 (r: 1.44-17.81) years. The most common diagnosis was PIK3CA-related overgrowth spectrum (PROS) (37/50). The median number of affected segments was 2 (r: 1-7) per patient. Vascular malformations were observed in 40, and capillary malformations, in 20 patients. Pain was the most common complication (24/50). An asymmetry of the lower extremities of < 5 cm was observed in 31 patients. In most children, height was between the 50th and 97th percentiles. A lower HRQoL was observed among girls, patients with complex vascular malformations, and those with unmet basic needs (UBNs). Conclusions. PROS was the most common diagnosis. Pain was the most common complication. HRQoL was lower among girls, patients with combined vascular malformations, and those with UBNs.
Introducción. Los síndromes de sobrecrecimiento corporal segmentario son un grupo de enfermedades poco frecuentes caracterizadas por exceso de crecimiento en una o más partes del cuerpo relacionadas, en su mayoría, con mutaciones en mosaico en la vía de señalización AKT/PI3K/mTOR y RAS-MAPK. Nuestro objetivo fue analizar las características clínicas y auxológicas, y la calidad de vida relacionada a salud (CVRS) en este grupo de pacientes en un hospital de tercer nivel de atención. Población y métodos. Estudio transversal de una cohorte en seguimiento. Se analizaron edad, sexo, datos sociodemográficos, mediciones antropométricas del segmento afectado y del contralateral, complicaciones, tratamiento, calidad de vida (PedsQL4.0) y dolor. Se calcularon medidas centrales y de dispersión. Se realizó análisis univariado entre calidad de vida y variables incluidas. Resultados. Se incluyeron 50 pacientes, 29 varones. Mediana de edad 9,95 (r 1,44-17,81) años. El diagnóstico más frecuente fue síndrome de sobrecrecimiento relacionado a PIK3CA (PROS) (37/50). Mediana de número de segmentos afectados 2 (r: 1-7) por niño. Cuarenta casos presentaron malformación vascular; 20, capilar. El dolor (24/50) fue la complicación más frecuente. Treinta y un pacientes mostraron asimetría de longitud de miembros inferiores, < 5 cm. La estatura se ubicó entre los centilos 50 y 97 en la mayoría de los niños. Menor CVRS se observó en mujeres, en pacientes con malformación vascular compleja y necesidades básicas insatisfechas (NBI). Conclusiones. PROS fue el diagnóstico más frecuente. El dolor fue una complicación frecuente. La CVRS fue menor en mujeres, pacientes con malformación vascular combinada y NBI.
Assuntos
Qualidade de Vida , Malformações Vasculares , Masculino , Feminino , Humanos , Criança , Adolescente , Estudos Transversais , Transdução de Sinais , Mutação , Síndrome , DorRESUMO
(1) There are several patients with asthma-COPD overlap (ACO). A peptide derived from the primary sequence of a kallikrein inhibitor isolated from Bauhinia bauhinioides (pep-BbKI) has potent anti-inflammatory and antioxidant effects. Purpose: To investigate the effects of pep-BbKI treatment in an ACO model and compare them with those of corticosteroids. (2) BALB/c mice were divided into groups: SAL (saline), OVA (ovalbumin), ELA (elastase), ACO (ovalbumin + elastase), ACO-pep-BbKI (treated with inhibitor), ACO-DX (dexamethasone treatment), ACO-DX-pep-BbKI (both treatments), and SAL-pep-BbKI (saline group treated with inhibitor). We evaluated: hyperresponsiveness to methacholine, bronchoalveolar lavage fluid (BALF), exhaled nitric oxide (eNO), IL-1ß, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, IFN-γ, TNF-α, MMP-9, MMP-12, TGF-ß, collagen fibers, iNOS, eNO, linear mean intercept (Lm), and NF-κB in airways (AW) and alveolar septa (AS). (3) ACO-pep-BbKI reversed ACO alterations and was similar to SAL in all mechanical parameters, Lm, neutrophils, IL-5, IL-10, IL-17, IFN-γ, TNF-α, MMP-12 (AW), collagen fibers, iNOS (AW), and eNO (p > 0.05). ACO-DX reversed ACO alterations and was similar to SAL in all mechanical parameters, Lm, total cells and differentials, IL-1ß(AS), IL-5 (AS), IL-6 (AS), IL-10 (AS), IL-13 (AS), IFN-γ, MMP-12 (AS), TGF-ß (AS), collagen fibers (AW), iNOS, and eNO (p > 0.05). SAL was similar to SAL-pep-BbKI for all comparisons (p > 0.05). (4) Pep-BbKI was similar to dexamethasone in reducing the majority of alterations of this ACO model.