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1.
Adv Exp Med Biol ; 1141: 101-202, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571165

RESUMO

Solute carrier (SLC) family transporters utilize an electrochemical potential difference or an ion gradient generated by primary active transporters for transporting their substrates across biological membranes. These transporters are categorized as facilitated transporters or secondary active transporters. More than 300 SLC transporters have been identified. SLC transporters related to drug transport mainly include SLC21 gene subfamily (organic anion-transporting polypeptides, OATPs), SLC22A gene subfamily (organic anion transporters, OATs; organic cation transporters, OCTs; or organic cation/carnitine transporters, OCTNs), SLC15A gene subfamily (peptide transporters, PEPTs), and SLC47A gene subfamily (multidrug and toxin extrusion, MATEs). In general, OCTs transport organic cations, OATPs transport large and fairly hydrophobic organic anions, OATs transport the smaller and more hydrophilic organic anions, and PEPTs are responsible for the uptake of di-/tripeptides and peptide-like drugs. MATEs are responsible for efflux of organic cations. These transporters also transport some endogenous substances, indicating that the dysfunction of SLCs not only disrupts homeostasis but also largely impacts on the disposition of their substrate drugs. This chapter will discuss these SLC family transporters, with an emphasis on tissue distribution, substrate specificity, transporter physiology, and clinical significance.


Assuntos
Proteínas Carreadoras de Solutos , Animais , Cátions/metabolismo , Humanos , Peptídeos/metabolismo , Preparações Farmacêuticas/metabolismo , Proteínas Carreadoras de Solutos/metabolismo , Especificidade por Substrato , Distribuição Tecidual/fisiologia
2.
Chem Commun (Camb) ; 55(69): 10192-10213, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31411602

RESUMO

Light is unsurpassed in its ability to modulate biological interactions. Since their discovery, chemists have been fascinated by photosensitive molecules capable of switching between isomeric forms, known as photoswitches. Photoswitchable peptides have been recognized for many years; however, their functional implementation in biological systems has only recently been achieved. Peptides are now acknowledged as excellent protein-protein interaction modulators and have been important in the emergence of photopharmacology. In this review, we briefly explain the different classes of photoswitches and summarize structural studies when they are incorporated into peptides. Importantly, we provide a detailed overview of the rapidly increasing number of examples, where biological modulation is driven by the structural changes. Furthermore, we discuss some of the remaining challenges faced in this field. These exciting proof-of-principle studies highlight the tremendous potential of photocontrollable peptides as optochemical tools for chemical biology and biomedicine.


Assuntos
Descoberta de Drogas , Peptídeos/química , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Morte Celular/efeitos dos fármacos , Descoberta de Drogas/métodos , Humanos , Isomerismo , Luz , Modelos Moleculares , Ácidos Nucleicos/metabolismo , Peptídeos/metabolismo , Processos Fotoquímicos , Mapas de Interação de Proteínas/efeitos dos fármacos
3.
Arch Endocrinol Metab ; 63(4): 394-401, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365627

RESUMO

OBJECTIVE: To measure type 1 serum amino-terminal propeptide procollagen (P1NP) and type 1 cross-linked C-terminal telopeptide collagen (CTX) before parathyroidectomy (PTX) in PHPT patients, correlating these measurements with bone mineral density (BMD) changes. SUBJECTS AND METHODS: 31 primary hyperparathyroidism (HPTP) were followed from diagnosis up to 12-18 months after surgery. Serum levels of calcium, parathyroid hormone (PTH) vitamin D, CTX, P1NP, and BMD were measured before and 1 year after surgery. RESULTS: One year after PTX, the mean BMD increased by 8.6%, 5.5%, 5.5%, and 2.2% in the lumbar spine, femoral neck (FN), total hip (TH), and distal third of the nondominant radius (R33%), respectively. There was a significant correlation between BMD change 1 year after the PTX and CTX (L1-L4: r = 0.614, p < 0.0003; FN: r = 0.497, p < 0.0051; TH: r = 0.595, p < 0.0005; R33%: r = 0.364, p < 0.043) and P1NP (L1-L4: r = 0,687, p < 0,0001; FN: r = 0,533, p < 0,0024; TH: r = 0,642, p < 0,0001; R33%: r = 0,467, p < 0,0079) preoperative levels. The increase in 25(OH)D levels has no correlation with BMD increase (r = -0.135; p = 0.4816). On linear regression, a minimum preoperative CTX value of 0.331 ng/mL or P1NP of 37.9 ng/mL was associated with a minimum 4% increase in L1-L4 BMD. In TH, minimum preoperative values of 0.684 ng/mL for CTX and 76.0 ng/mL for P1NP were associated with a ≥ 4% increase in BMD. CONCLUSION: PHPT patients presented a significant correlation between preoperative levels of turnover markers and BMD improvement 1 year after PTX.


Assuntos
Densidade Óssea , Colágeno Tipo I/metabolismo , Hiperparatireoidismo Primário/metabolismo , Paratireoidectomia/reabilitação , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Pró-Colágeno/metabolismo , Idoso , Biomarcadores/sangue , Cálcio/sangue , Feminino , Humanos , Hiperparatireoidismo Primário/cirurgia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fragmentos de Peptídeos/sangue , Período Pós-Operatório , Valor Preditivo dos Testes , Período Pré-Operatório , Pró-Colágeno/sangue , Estudos Retrospectivos , Vitamina D/sangue
4.
Cell Physiol Biochem ; 53(2): 413-428, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31415717

RESUMO

BACKGROUND/AIMS: Amyloid plaques, generated during the progression of Alzheimer's disease, cause major neurological deficits due to substantial cell toxicity and death. The underlying cause of plaque generation stems from cleavage of the amyloid precursor protein (APP) by ß-secretase (BACE1). A resulting amyloid-ß (Aß) fragment forms aggregates to produce the main constituent of a plaque. METHODS: Phage display and biopanning techniques were used to identify a 12-mer peptide that had a natural affinity for the BACE1 enzyme. The peptide was translated from phage DNA and synthetically produced. The peptide, at concentrations of 1nM, 10nM and 100nM, was used to confirm binding by direct assay. Non-specific binding to BACE2, renin and cathepsin D was tested by direct binding assay. A BACE1 activity assay was used to determine the peptide effect on cleavage of an APP substrate. Treatment of SY5Y cells with the peptide was used to determine toxicity and prevention of Aß40 and Aß42 production. RESULTS: After identification and synthetic production, the peptide exhibited a strong affinity for BACE1 at nanomolar concentrations in the direct assay. In case of non-specific binding to homologous BACE2, renin and cathepsin D, the peptide showed minor binding but was nullified when in solution with BACE1. The peptide addition to a BACE1 activity assay was able to significantly reduce the amount of substrate cleavage. SY5Y cells, when treated with the peptide, did not show any detrimental morphological changes while being able to reduce the production of natural Aß40 and Aß42. Even under stressed conditions (H2O2 treatment) where the Aß production was higher, the peptide was still able to significantly reduce the effect of BACE1 while not effecting cell viability. CONCLUSION: The identified peptide exhibited strong binding to BACE1 in vitro and was able to reduce production of Aß, suggesting a favourable BACE1 inhibitor for future refining and characterisation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Peptídeos/farmacologia , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular , Descoberta de Drogas , Inibidores Enzimáticos/metabolismo , Humanos , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo
5.
J Agric Food Chem ; 67(31): 8500-8509, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298534

RESUMO

To map qualitative and quantitative metabolome alterations when Penicillium roqueforti is grown in an environment where l-tyrosine levels are perturbed, the recently established differential off-line LC-NMR (DOLC-NMR) approach was successfully applied in connection with an absolute metabolite quantitation using a quantitative 1H NMR protocol following the ERETIC 2 (Electronic REference To access In vivo Concentrations) methodology. Among the 23 influenced metabolites, amino acid degradation products like 2-(4-hydroxyphenyl)acetic acid and 2-(3,4-dihydroxyphenyl)acetic acid underwent a tremendous upregulation in the amino acid perturbed approach. Moreover, the output of secondary metabolites like andrastin A, eremofortin B, and the tetrapeptide d-Phe-l-Val-d-Val-l-Tyr was affected in the case of the presence or absence of the added aromatic amino acid. Furthermore, the isolated secondary metabolites of P. roqueforti have been quantified for the first time in five divergent Penicillium isolates by means of a validated LC-ECHO-MS/MS method. This technique is used to compensate the effect of co-extracted matrix compounds during the analysis and to utilize quasi-internal standards to quantify all metabolites of interest accurately. This screening outlined the great variety between the different fungi of the same species. The metabolite spectra of wild-type fungi included more toxic intermediates compared to a selected fungi used as a starter culture for blue-mold cheese production. In addition, these secondary metabolites were quantified in commercially available white- and blue-mold cheese samples. The main differences between the analyte profiles of white and blue cheeses were linked to the impact of the used starter culture. Specific metabolites detected from P. roqueforti like andrastin A and B or roquefortine C could not be detected in white cheese. Among the blue cheese samples, different metabolite pattern could be observed regarding various P. roqueforti starter cultures.


Assuntos
Queijo/microbiologia , Metaboloma , Penicillium/metabolismo , Metabolismo Secundário , Tirosina/metabolismo , Aminoácidos Aromáticos/análise , Aminoácidos Aromáticos/metabolismo , Androstadienos/análise , Androstadienos/metabolismo , Queijo/análise , Penicillium/química , Penicillium/crescimento & desenvolvimento , Peptídeos/análise , Peptídeos/metabolismo , Sesquiterpenos/análise , Sesquiterpenos/metabolismo , Espectrometria de Massas em Tandem
6.
Chem Commun (Camb) ; 55(61): 8959-8962, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31290487

RESUMO

Hydrocarbon stapled peptides are promising therapeutics for inhibition of intracellular protein-protein interactions. Here we develop a new high-throughput strategy for hydrocarbon stapled peptide discovery based on mRNA display of peptides containing α-methyl cysteine and cyclized with m-dibromoxylene. We focus on development of a peptide binder to the HPV16 E2 protein.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Evolução Molecular Direcionada/métodos , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Peptídeos/metabolismo , Engenharia de Proteínas/métodos , Fatores de Transcrição/metabolismo , Alquilação , Sequência de Aminoácidos , Ciclização , Cisteína/química , Hidrocarbonetos Bromados/química , Biblioteca de Peptídeos , Peptídeos/química , Ligação Proteica/efeitos dos fármacos , RNA Mensageiro/química
7.
J Agric Food Chem ; 67(30): 8370-8381, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31271280

RESUMO

Naturally occurring dietary peptides derived from gastrointestinal digestates of common bean milk and yogurt were studied for their bioaccessibility, bioavailability, and anti-inflammatory activity in both Caco-2 mono- and Caco-2/EA.hy926 co-culture cell models. Anti-inflammatory activities of these peptide extracts were found to be strongly associated with cellular uptake by the intestinal epithelial cells. Mechanisms underlying the cellular uptake were studied by examining the role of peptide transporter 1 and calcium sensing reporter. Three peptides, including γ-glutamyl-S-methylcysteine, γ-glutamyl-leucine, and leucine-leucine-valine, were found to be transported across the Caco-2 cell monolayer and detected by liquid chromatography-tandem mass spectrometry. A strong anti-inflammatory effect was observed in the basolateral EA.hy926 cells (co-culture model), as shown in their inhibition of tumor necrosis factor α-induced pro-inflammatory mediators of the nuclear factor κB and mitogen-activated protein kinase signal cascades. The results suggest that these peptides can be absorbed and possibly have systemic inhibition on inflammatory responses in vascular endothelial cells, indicating potential preventive effects on vascular diseases.


Assuntos
Anti-Inflamatórios/metabolismo , Células Endoteliais/metabolismo , Peptídeos/metabolismo , Phaseolus/química , Extratos Vegetais/metabolismo , Iogurte/análise , Transporte Biológico , Células CACO-2 , Técnicas de Cocultura , Células Epiteliais/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Intestinos/citologia , NF-kappa B/genética , NF-kappa B/metabolismo , Transportador 1 de Peptídeos/genética , Transportador 1 de Peptídeos/metabolismo , Peptídeos/química , Phaseolus/metabolismo , Extratos Vegetais/química
8.
Chem Commun (Camb) ; 55(62): 9188-9191, 2019 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-31305808

RESUMO

The metal salts ubiquitously present in biological samples cause serious ion suppression, capillary clogging and signal fluctuation in ESI/nESI. Herein, a current-limited high voltage polarity reversing approach was applied for the online separation of intrinsic metal ions in biological samples, resulting in the generation of protonated analytes at the nESI tip for mass analysis without interference from salt cations. Stable and durable signals (∼30-60 s) were observed for protonated proteins, peptides and metabolites in complex biological samples, including liquids, solids and viscous samples, even with very high salt concentration (100 mM NaCl), allowing comprehensive tandem MS analysis with on average ca. 5-times higher analyte signal intensities compared to the conventional nESI analysis. Therefore this approach offers improved performance of nESI/ESI for the sensitive molecular analysis of untreated biological samples, opening new possibilities in various disciplines, including biology, medicine, chemistry, life sciences, etc.


Assuntos
Peptídeos/análise , Proteínas/análise , Cloreto de Sódio/química , Íons/análise , Peptídeos/metabolismo , Proteínas/metabolismo , Prótons , Espectrometria de Massas por Ionização por Electrospray/instrumentação
9.
Anal Chim Acta ; 1078: 112-118, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31358208

RESUMO

Herein, an array-based in situ fluorescence assay is proposed for high-throughput analysis and localization of multiplex matrix metalloproteinases (MMPs) activities in cell monolayers and tissue sections. Five specific MMPs (MMP-2, -3, -7, -9, and -14) peptide substrates containing FAM/Dabcyl fluorescent resonance energy transfer (FRET) pair are directly spotted on the surface of cell monolayers or tissue sections, and hydrolyzed by localized MMPs, resulting in fluorescence recovery of FAM. MMPs activities are determined by the fluorescence intensity of stained cells/tissues due to the cellular internalization of peptide fragments with FAM moiety. We demonstrate that the array-based in situ fluorescence assay is suitable for identifying the MMPs expression patterns of cells, as well as determining the secreted MMPs activities in cell monolayer with high sensitivity (as low as hundreds of cells per square centimeter). The feasibility of the assay is further confirmed by evaluating inhibition potencies of six compounds toward five MMPs. Profiling of five MMPs activities in the localized parts of 32 thyroid tissues is performed without separation or extraction procedures, demonstrating the good practicality of the method.


Assuntos
Ensaios Enzimáticos/métodos , Metaloproteinases da Matriz/análise , Microscopia de Fluorescência/métodos , Peptídeos/metabolismo , Linhagem Celular Tumoral , Fluoresceínas/química , Fluorescência , Corantes Fluorescentes/química , Humanos , Hidrólise , Inibidores de Metaloproteinases de Matriz/farmacologia , Metaloproteinases da Matriz/metabolismo , Peptídeos/química , Estudo de Prova de Conceito , Glândula Tireoide/metabolismo
10.
Life Sci ; 231: 116674, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31344427

RESUMO

Hypertrophic scar formation is a fibroproliferative disorder caused by abnormal wound healing. At present, there are limited treatment strategies for hypertrophic scars. In this study, we identified an endogenous peptide, LYENRL, through peptidomics screening that is downregulated in scar skin tissues. The peptide exhibited concentration dependent inhibitory effects on the proliferation, migration and extracellular matrix (ECM) production of scar fibroblasts. By eukaryotic transcriptome sequencing analysis, we noted that LYENRL downregulated gene sets in scar fibroblasts were associated with the transforming growth factor-ß (TGF-ß) signaling pathway. Further experiments revealed that LYENRL was able to inhibit the activation of TGF-ß1/Smad signaling and TGF-ß1-induced activation of scar fibroblasts at the source by blocking the binding of AP-1 to the corresponding region of the Tgfb1 promoter, which in turn inhibited gene expression of Tgfb1. Taken together, we concluded that the effects of LYENRL on scar fibroblasts make it a potential peptide drug for hypertrophic scar treatment.


Assuntos
Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patologia , Peptídeos/farmacologia , Actinas/metabolismo , Linhagem Celular , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Matriz Extracelular/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Humanos , Peptídeos/metabolismo , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos , Pele/metabolismo , Proteínas Smad/metabolismo , Proteínas Smad/fisiologia , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/fisiologia
11.
Medicine (Baltimore) ; 98(30): e16534, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31348270

RESUMO

BACKGROUND: High-grade prostate cancer (PCa) has a poor prognosis, and up to 15% of patients worldwide experience lymph node invasion (LNI). To further improve the prediction lymph node invasion in prostate cancer, we adopted risk scores of the genes expression based on the nomogram in guidelines. METHODS: We analyzed clinical data from 320 PCa patients from the Cancer Genome Atlas database. Weighted gene coexpression network analysis was used to identify the genes that were significantly associated with LNI in PCa (n = 390). Analyses using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases were performed to identify the activated signaling pathways. Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors for the presence of LNI. RESULTS: We found that patients with actual LNI and predicted LNI had the worst survival outcomes. The 7 most significant genes (CTNNAL1, ENSA, MAP6D1, MBD4, PRCC, SF3B2, TREML1) were selected for further analysis. Pathways in the cell cycle, DNA replication, oocyte meiosis, and 9 other pathways were dramatically activated during LNI in PCa. Multivariate analyses identified that the risk score (odds ratio [OR] = 1.05 for 1% increase, 95% confidence interval [CI]: 1.04-1.07, P < .001), serum PSA level, clinical stage, primary biopsy Gleason grade (OR = 2.52 for a grade increase, 95% CI: 1.27-5.22, P = .096), and secondary biopsy Gleason grade were independent predictors of LNI. A nomogram built using these predictive variables showed good calibration and a net clinical benefit, with an area under the curve (AUC) value of 90.2%. CONCLUSIONS: In clinical practice, the application of our nomogram might contribute significantly to the selection of patients who are good candidates for surgery with extended pelvic lymph node dissection.


Assuntos
Biomarcadores Tumorais/genética , Metástase Linfática/genética , Nomogramas , Neoplasias da Próstata/genética , Idoso , Área Sob a Curva , Proteínas de Ciclo Celular/metabolismo , Bases de Dados Genéticas , Endodesoxirribonucleases/metabolismo , Humanos , Modelos Logísticos , Linfonodos/patologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Proteínas de Neoplasias/metabolismo , Razão de Chances , Peptídeos/metabolismo , Valor Preditivo dos Testes , Neoplasias da Próstata/patologia , Fatores de Processamento de RNA/metabolismo , Receptores Imunológicos/metabolismo , Reprodutibilidade dos Testes , Fatores de Risco , alfa Catenina/metabolismo
12.
Chem Commun (Camb) ; 55(49): 7085-7088, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31150032

RESUMO

A luminescent biosensor has been developed for matrix metalloproteinase 9 (MMP-9) assays based on the selective interaction between an Ir(iii) solvent complex and a histidine-rich peptide, which avoids the complicated double labeling of substrate polypeptides commonly-used in FRET MMP detections and provides a promising strategy for MMP detection in clinical applications.


Assuntos
Técnicas Biossensoriais , Complexos de Coordenação/química , Histidina/química , Irídio/química , Metaloproteinase 9 da Matriz/análise , Peptídeos/química , Complexos de Coordenação/metabolismo , Transferência Ressonante de Energia de Fluorescência , Histidina/metabolismo , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Peptídeos/metabolismo , Solventes/química
13.
Nat Commun ; 10(1): 2393, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160557

RESUMO

Bacterial ClpB and yeast Hsp104 are homologous Hsp100 protein disaggregases that serve critical functions in proteostasis by solubilizing protein aggregates. Two AAA+ nucleotide binding domains (NBDs) power polypeptide translocation through a central channel comprised of a hexameric spiral of protomers that contact substrate via conserved pore-loop interactions. Here we report cryo-EM structures of a hyperactive ClpB variant bound to the model substrate, casein in the presence of slowly hydrolysable ATPγS, which reveal the translocation mechanism. Distinct substrate-gripping interactions are identified for NBD1 and NBD2 pore loops. A trimer of N-terminal domains define a channel entrance that binds the polypeptide substrate adjacent to the topmost NBD1 contact. NBD conformations at the seam interface reveal how ATP hydrolysis-driven substrate disengagement and re-binding are precisely tuned to drive a directional, stepwise translocation cycle.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Caseínas/metabolismo , Endopeptidase Clp/ultraestrutura , Proteínas de Escherichia coli/ultraestrutura , Escherichia coli/metabolismo , Proteínas de Choque Térmico/ultraestrutura , Transporte Proteico , Domínio AAA , Trifosfato de Adenosina/metabolismo , Microscopia Crioeletrônica , Endopeptidase Clp/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Choque Térmico/metabolismo , Hidrólise , Modelos Moleculares , Peptídeos/metabolismo , Agregados Proteicos , Subunidades Proteicas/metabolismo
14.
J Sci Food Agric ; 99(13): 5819-5825, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31180140

RESUMO

BACKGROUND: Xinong Saanen goat milk is a raw material for goat milk-based infant formula production. This study aims to analyze digestion properties of Xinong Saanen goat colostrum and mature milk by simulating infant gastrointestinal digestion. Zeta potential, particles size, protein profile and peptides composition of these two kinds of milk during the digestion process were studied. RESULTS: Zeta-potential values of the digested colostrum were lower than those of mature milk through the whole digestion. Absolute zeta potential of colostrum duodenal digestion samples showed a decrease from 16.63 ± 2.08 to 11.80 ± 2.03 mV while that of mature milk decreased sharply and then increased (P < 0.05). Colostrum had a larger particle size than mature milk and both milks showed decreased particle size with increasing digestion time but an increase for the last 30 min. Colostrum showed more high molecular weight (MW) proteins which cannot be hydrolyzed completely compared with mature milk. Digested peptides (< 10 kDa) were characterized using liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). The casein-derived peptides identified in digested colostrum and mature milk accounted for 76.67% and 59.53%, respectively. ß-Casein was the most abundant in colostrum while that in mature milk was αs1 -casein. Enterotoxin-binding glycoprotein PP20K, butyrophilin subfamily 1 member A1 (BTN1A1) and perilipin (PLIN) were only detected in digested mature milk. CONCLUSION: Differences in digestion properties between goat colostrum and mature milk were mainly shown in duodenal digestion phase. Data may provide useful information about utilization of goat milk for infant formula formulation. © 2019 Society of Chemical Industry.


Assuntos
Colostro/metabolismo , Digestão , Trato Gastrointestinal/metabolismo , Fórmulas Infantis/análise , Leite/metabolismo , Proteínas/metabolismo , Animais , Cromatografia Líquida , Colostro/química , Cabras , Humanos , Lactente , Leite/química , Modelos Biológicos , Peptídeos/química , Peptídeos/metabolismo , Proteínas/química , Espectrometria de Massas em Tandem
15.
Adv Gerontol ; 32(1-2): 174-179, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31228385

RESUMO

In review it is shown data about polypeptide vessel complex, extracted from calf vessel and named Slavinorm® (Vasolin). Slavinorm® had therapeutic effects in cardio-vascular age related pathology in animal models. Slavinorm® prevents atherosclerosis, normalizes lipid metabolism, lipid peroxidation parameters, station of congenital and adaptive immunity, callicrein-kinins system, vessel and trombocitary hemostasis, blood coagulability, fibrinolysis, activates vessel wall reparation. Slavinorm® has positive effects in other age-related diseases (arthritis, pancreatitis, respiratory distress).


Assuntos
Envelhecimento , Aterosclerose , Peptídeos , Animais , Fibrinólise , Hemostasia , Peptídeos/metabolismo
16.
Dokl Biochem Biophys ; 485(1): 115-118, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31201628

RESUMO

Genetic analysis of thousands of patients with multiple sclerosis (MS) and healthy Russian donors showed that the carriage of groups of HLA-DRB1*15 and HLA-DRB1*03 alleles is associated with the risk of MS, whereas the carriage of groups of HLA-DRB1*01 and HLA-DRB1*11 alleles is protective. Recombinant HLA-DRB1*01:01 with a high affinity can recognize the fragments of myelin basic protein (MBP), one of the autoantigens in MS. However, the comparison of the kinetic parameters of the load of MBP and viral HA peptides on HLA-DRB1*01:01, which is catalyzed by HLA-DM, showed a significantly lower rate of exchange of CLIP for MBP peptides. We assume that the observed protective properties of the group of HLA-DRB1*01 alleles may be directly associated with the ability of HLA-DRB1*01:01 to kinetically distinguish peptides of exogenous and endogenous nature.


Assuntos
Autoantígenos/metabolismo , Cadeias HLA-DRB1/metabolismo , Esclerose Múltipla/metabolismo , Proteína Básica da Mielina/metabolismo , Peptídeos/metabolismo , Autoantígenos/química , Autoantígenos/genética , Feminino , Cadeias HLA-DRB1/química , Cadeias HLA-DRB1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/genética , Proteína Básica da Mielina/química , Proteína Básica da Mielina/genética , Peptídeos/química , Peptídeos/genética
17.
Anal Bioanal Chem ; 411(19): 4987-4998, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31254054

RESUMO

Influenza infection requires viral escape from early endosomes into the cytosol, which is enabled by an acid-induced irreversible conformational transformation in the viral protein hemagglutinin. Despite the direct relationship between this conformational change and infectivity, label-free methods for characterizing this and other protein conformational changes in biological mixtures are limited. While the chemical reactivity of the protein backbone and side-chain residues is a proxy for protein conformation, coupling this reactivity to quantitative mass spectrometry is a challenge in complex environments. Herein, we evaluate whether electrophilic amidination coupled with pseudo-parallel reaction monitoring is an effective label-free approach to detect the fusion-associated conformational transformation in recombinant hemagglutinin (rHA). We identified rHA peptides that are differentially amidinated between the pre- and post-fusion states, and validated that this difference relies upon the fusion-associated conformational switch. We further demonstrate that we can distinguish the fusion profile in a matrix of digested cellular lysate. This fusion assay can be used to evaluate fusion competence for modified HA. Graphical abstract.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Orthomyxoviridae/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Virais/metabolismo , Amidas/metabolismo , Células HEK293 , Humanos , Limite de Detecção , Peptídeos/metabolismo , Ligação Proteica , Conformação Proteica , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Proteínas Virais/química , Proteínas Virais/classificação
18.
Food Chem ; 295: 456-465, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174782

RESUMO

Kefir is a fermented dairy product, associated to health benefits because of being a probiotic and due to the presence of molecules with biological activity. In this work, we have profiled the peptide composition of goat milk kefir at three different fermentation times using a peptidomics approach, in order to study changes in peptide concentrations and patterns of protein digestion throughout the fermentation time. We identified 2328 unique peptides corresponding to 22 protein annotations, with a maximum of peptides found after 24 h fermentation. We established different digestion patterns according to the nature of the proteins, and quantified the changes in the peptides appearing in all the fermentation times. We also identified 11 peptides that matched exactly to sequences with biological activity in databases, almost all of them belonging to caseins. This is the most comprehensive proteomic analysis of goat milk kefir to date.


Assuntos
Kefir/análise , Proteínas do Leite/análise , Peptídeos/análise , Peptídeos/farmacologia , Animais , Caseínas/análise , Caseínas/metabolismo , Fermentação , Cabras , Proteínas do Leite/metabolismo , Proteínas do Leite/farmacologia , Mapeamento de Peptídeos/métodos , Peptídeos/metabolismo , Probióticos , Proteólise , Proteômica/métodos , Fatores de Tempo
19.
Chem Commun (Camb) ; 55(52): 7474-7477, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31184664

RESUMO

Inspired by clinical studies on alcohol abuse induced endoplasmic reticulum disruption, we designed a N-hydroxylethyl peptide assembly to regulate the ER stress response in cancer cells. Upon coupling with a coumarin derivative via an ester linkage, a prodrug was synthesized to promote esterase-facilitated self-delivery of N-hydroxylethyl peptide assemblies around the ER, inducing ER dilation. Following this, ER-specific apoptosis was effectively and efficiently activated in various types of cancer cells including drug resistant and metastatic ones.


Assuntos
Citosol/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Peptídeos/farmacologia , Apoptose/efeitos dos fármacos , Carboxilesterase/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cumarínicos/química , Humanos , Microscopia de Fluorescência , Peptídeos/metabolismo , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia
20.
World J Microbiol Biotechnol ; 35(6): 92, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31187317

RESUMO

Polyketides and peptides obtained from actinobacteria are important therapeutic compounds which include front line antibiotics and anticancer drugs. Many screening programs are directed towards isolation of bioactive compounds from these organisms but the chances of finding novel antimicrobial leads among common actinobacteria are fast dwindling. As a result, the focus has shifted to the members of less exploited genera of rare actinobacteria. Three isolates, MMS8, MMS16 and KCR3 found to be potent polyketide and peptide producers were identified by 16S rRNA gene sequencing and their sequences deposited in the GenBank under the accession numbers MG407702, MG372012 and MG430204 respectively. MMS8 identified as Micromonospora auratinigra, yielded one potent compound determined to be chloroanthraquinone with an minimum inhibitory concentration (MIC) of 8 µg/ml against Bacillus subtilis and an IC50 value of 10 µg/ml and 4 µg/ml against HeLa and IMR cell lines respectively. This is the first report of the production of chloroanthraquinone by M. auratinigra. MMS16, identified as a member of the family Micromonosporaceae, yielded a potent compound MMS16B analyzed to be a novel bafilomycin analogue. The MIC of the compound was found to be 7 µg/ml against B.subtilis and IC50 value against HeLa and IMR was observed to be 9 µg/ml and 14 µg/ml respectively. MMS16B was also found to exhibit anti-quorum sensing (AQS) activity at sublethal concentrations. KCR3 identified as Kocuria kristinae yielded a novel antimicrobial peptide with antibacterial, antifungal and AQS activity. To the best of our knowledge, no antimicrobial activity has ever been reported from K. kristinae.


Assuntos
Actinobacteria/metabolismo , Peptídeos/metabolismo , Policetídeos/metabolismo , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Animais , Antibacterianos/metabolismo , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Antineoplásicos/metabolismo , Bacillus subtilis/efeitos dos fármacos , Linhagem Celular , Testes de Sensibilidade Microbiana , Micromonospora/genética , Micromonospora/isolamento & purificação , Micromonospora/metabolismo , Peptídeos/isolamento & purificação , Peptídeos/farmacologia , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , RNA Ribossômico 16S/genética
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