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1.
Proteomics ; : e2300294, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37772677

RESUMO

In proteomics, fast, efficient, and highly reproducible sample preparation is of utmost importance, particularly in view of fast scanning mass spectrometers enabling analyses of large sample series. To address this need, we have developed the web application MassSpecPreppy that operates on the open science OT-2 liquid handling robot from Opentrons. This platform can prepare up to 96 samples at once, performing tasks like BCA protein concentration determination, sample digestion with normalization, reduction/alkylation and peptide elution into vials or loading specified peptide amounts onto Evotips in an automated and flexible manner. The performance of the developed workflows using MassSpecPreppy was compared with standard manual sample preparation workflows. The BCA assay experiments revealed an average recovery of 101.3% (SD: ± 7.82%) for the MassSpecPreppy workflow, while the manual workflow had a recovery of 96.3% (SD: ± 9.73%). The species mix used in the evaluation experiments showed that 94.5% of protein groups for OT-2 digestion and 95% for manual digestion passed the significance thresholds with comparable peptide level coefficient of variations. These results demonstrate that MassSpecPreppy is a versatile and scalable platform for automated sample preparation, producing injection-ready samples for proteomics research.

2.
Eur J Neurol ; 30(4): 1048-1058, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36504168

RESUMO

BACKGROUND AND PURPOSE: Idiopathic facial palsy (IFP) accounts for over 60% of peripheral facial palsy (FP) cases. The cause of IFP remains to be determined. Possible etiologies are nerve swelling due to inflammation and/or viral infection. In this study, we applied an integrative mass spectrometry approach to identify possibly altered protein patterns in the cerebrospinal fluid (CSF) of IFP patients. METHODS: We obtained CSF samples from 34 patients with FP. In four patients, varicella-zoster virus was the cause (VZV-FP). Among the 30 patients diagnosed with IFP, 17 had normal CSF parameters, five had slightly elevated CSF cell counts and normal or elevated CSF protein, and eight had normal CSF cell counts but elevated CSF protein. Five patients with primary headache served as controls. All samples were tested for viral pathogens by PCR and subjected to liquid chromatography tandem mass spectrometry and bioinformatics analysis and multiplex cytokine/chemokine arrays. RESULTS: All CSF samples, except those from VZV-FP patients, were negative for all tested pathogens. The protein composition of CSF samples from IFP patients with normal CSF was comparable to controls. IFP patients with elevated CSF protein showed dysregulated proteins involved in inflammatory pathways, findings which were similar to those in VZV-FP patients. Multiplex analysis revealed similarly elevated cytokine levels in the CSF of IFP patients with elevated CSF protein and VZV-FP. CONCLUSIONS: Our study revealed a subgroup of IFP patients with elevated CSF protein that showed upregulated inflammatory pathways, suggesting an inflammatory/infectious cause. However, no evidence for an inflammatory cause was found in IFP patients with normal CSF.


Assuntos
Paralisia de Bell , Paralisia Facial , Humanos , Paralisia Facial/etiologia , Nervo Facial , Proteômica , Paralisia de Bell/complicações , Paralisia de Bell/diagnóstico , Herpesvirus Humano 3 , Citocinas , Líquido Cefalorraquidiano
3.
Proc Natl Acad Sci U S A ; 117(12): 6752-6761, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32144140

RESUMO

A type of chromosome-free cell called SimCells (simple cells) has been generated from Escherichia coli, Pseudomonas putida, and Ralstonia eutropha. The removal of the native chromosomes of these bacteria was achieved by double-stranded breaks made by heterologous I-CeuI endonuclease and the degradation activity of endogenous nucleases. We have shown that the cellular machinery remained functional in these chromosome-free SimCells and was able to process various genetic circuits. This includes the glycolysis pathway (composed of 10 genes) and inducible genetic circuits. It was found that the glycolysis pathway significantly extended longevity of SimCells due to its ability to regenerate ATP and NADH/NADPH. The SimCells were able to continuously express synthetic genetic circuits for 10 d after chromosome removal. As a proof of principle, we demonstrated that SimCells can be used as a safe agent (as they cannot replicate) for bacterial therapy. SimCells were used to synthesize catechol (a potent anticancer drug) from salicylic acid to inhibit lung, brain, and soft-tissue cancer cells. SimCells represent a simplified synthetic biology chassis that can be programmed to manufacture and deliver products safely without interference from the host genome.


Assuntos
Antineoplásicos/farmacologia , Catecóis/farmacologia , Reprogramação Celular , Cupriavidus necator/genética , Escherichia coli/genética , Pseudomonas putida/genética , Biologia Sintética/métodos , Proliferação de Células , Cromossomos Bacterianos , Cupriavidus necator/metabolismo , Sistemas de Liberação de Medicamentos , Escherichia coli/metabolismo , Redes Reguladoras de Genes , Engenharia Genética , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Pseudomonas putida/metabolismo , Células Tumorais Cultivadas
4.
Metabolomics ; 18(6): 39, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35687250

RESUMO

INTRODUCTION: Respiratory tract infections are a worldwide health problem for humans and animals. Different cell types produce lipid mediators in response to infections, which consist of eicosanoids like hydroxyeicosatetraenoic acids (HETEs) or oxylipins like hydroxydocosahexaenoic acids (HDHAs). Both substance classes possess immunomodulatory functions. However, little is known about their role in respiratory infections. OBJECTIVES: Here, we aimed to analyze the lipid mediator imprint of different organs of C57BL/6J mice after intranasal mono-infections with Streptococcus pneumoniae (pneumococcus), Staphylococcus aureus or Influenza A virus (IAV) as wells as pneumococcal-IAV co-infection. METHODS: C57BL/6J mice were infected with different pathogens and lungs, spleen, and plasma were collected. Lipid mediators were analyzed using HPLC-MS/MS. In addition, spatial-distribution of sphingosine 1-phosphate (S1P) and ceramide 1-phosphates (C1P) in tissue samples was examined using MALDI-MS-Imaging. The presence of bacterial pathogens in the lung was confirmed via immunofluorescence staining. RESULTS: We found IAV specific changes for different HDHAs and HETEs in mouse lungs as well as enhanced levels of 20-HETE in severe S. aureus infection. Moreover, MALDI-MS-Imaging analysis showed an accumulation of C1P and a decrease of S1P during co-infection in lung and spleen. Long chain C1P was enriched in the red and not in the white pulp of the spleen. CONCLUSIONS: Lipid mediator analysis showed that host synthesis of bioactive lipids is in part specific for a certain pathogen, in particular for IAV infection. Furthermore, MS-Imaging displayed great potential to study infections and revealed changes of S1P and C1P in lungs and spleen of co-infected animals, which was not described before.


Assuntos
Coinfecção , Vírus da Influenza A , Infecções Respiratórias , Animais , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Staphylococcus aureus , Streptococcus pneumoniae , Espectrometria de Massas em Tandem
5.
Haematologica ; 107(4): 947-957, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35045692

RESUMO

Vector-based SARS-CoV-2 vaccines have been associated with vaccine- induced thrombosis with thrombocytopenia syndrome (VITT/TTS), but the causative factors are still unresolved. We comprehensively analyzed the ChAdOx1 nCoV-19 (AstraZeneca) and Ad26.COV2.S (Johnson and Johnson) vaccines. ChAdOx1 nCoV-19 contains significant amounts of host cell protein impurities, including functionally active proteasomes, and adenoviral proteins. A much smaller amount of impurities was found in Ad26.COV2.S. Platelet factor 4 formed complexes with ChAdOx1 nCoV-19 constituents, but not with purified virions from ChAdOx1 nCoV-19 or with Ad26.COV2.S. Vascular hyperpermeability was induced by ChAdOx nCoV-19 but not by Ad26.COV2.S. These differences in impurities together with EDTAinduced capillary leakage might contribute to the higher incidence rate of VITT associated with ChAdOx1 nCoV-19 compared to Ad26.COV2.S.


Assuntos
COVID-19 , Vacinas , Ad26COVS1 , Vacinas contra COVID-19/efeitos adversos , ChAdOx1 nCoV-19 , Humanos , SARS-CoV-2
6.
Mol Cell Proteomics ; 18(5): 892-908, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30808728

RESUMO

Staphylococcus aureus is infamous for causing recurrent infections of the human respiratory tract. This is a consequence of its ability to adapt to different niches, including the intracellular milieu of lung epithelial cells. To understand the dynamic interplay between epithelial cells and the intracellular pathogen, we dissected their interactions over 4 days by mass spectrometry. Additionally, we investigated the dynamics of infection through live cell imaging, immunofluorescence and electron microscopy. The results highlight a major role of often overlooked temporal changes in the bacterial and host metabolism, triggered by fierce competition over limited resources. Remarkably, replicating bacteria reside predominantly within membrane-enclosed compartments and induce apoptosis of the host within ∼24 h post infection. Surviving infected host cells carry a subpopulation of non-replicating bacteria in the cytoplasm that persists. Altogether, we conclude that, besides the production of virulence factors by bacteria, it is the way in which intracellular resources are used, and how host and intracellular bacteria subsequently adapt to each other that determines the ultimate outcome of the infectious process.


Assuntos
Brônquios/patologia , Endocitose , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/metabolismo , Apoptose , Proteínas de Bactérias/metabolismo , Linhagem Celular , Citosol/metabolismo , Células Epiteliais/ultraestrutura , Interações Hospedeiro-Patógeno , Humanos , Proteoma/metabolismo , Staphylococcus aureus/ultraestrutura
7.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502122

RESUMO

Extracellular vesicles (EVs) are reminiscent of their cell of origin and thus represent a valuable source of biomarkers. However, for EVs to be used as biomarkers in clinical practice, simple, comparable, and reproducible analytical methods must be applied. Although progress is being made in EV separation methods for human biofluids, the implementation of EV assays for clinical diagnosis and common guidelines are still lacking. We conducted a comprehensive analysis of established EV separation techniques from human serum and plasma, including ultracentrifugation and size exclusion chromatography (SEC), followed by concentration using (a) ultracentrifugation, (b) ultrafiltration, or (c) precipitation, and immunoaffinity isolation. We analyzed the size, number, protein, and miRNA content of the obtained EVs and assessed the functional delivery of EV cargo. Our results demonstrate that all methods led to an adequate yield of small EVs. While no significant difference in miRNA content was observed for the different separation methods, ultracentrifugation was best for subsequent flow cytometry analysis. Immunoaffinity isolation is not suitable for subsequent protein analyses. SEC + ultracentrifugation showed the best functional delivery of EV cargo. In summary, combining SEC with ultracentrifugation gives the highest yield of pure and functional EVs and allows reliable analysis of both protein and miRNA contents. We propose this combination as the preferred EV isolation method for biomarker studies from human serum or plasma.


Assuntos
Fracionamento Celular , Fracionamento Químico , Vesículas Extracelulares/metabolismo , Transporte Biológico , Biomarcadores , Fracionamento Celular/métodos , Fracionamento Químico/métodos , Vesículas Extracelulares/ultraestrutura , Citometria de Fluxo , Humanos , Biópsia Líquida/métodos , Proteínas/metabolismo
8.
J Infect Dis ; 222(10): 1702-1712, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32445565

RESUMO

BACKGROUND: In tissue infections, adenosine triphosphate (ATP) is released into extracellular space and contributes to purinergic chemotaxis. Neutrophils are important players in bacterial clearance and are recruited to the site of tissue infections. Pneumococcal infections can lead to uncontrolled hyperinflammation of the tissue along with substantial tissue damage through excessive neutrophil activation and uncontrolled granule release. We aimed to investigate the role of ATP in neutrophil response to pneumococcal infections. METHODS: Primary human neutrophils were exposed to the pneumococcal strain TIGR4 and its pneumolysin-deficient mutant or directly to different concentrations of recombinant pneumolysin. Neutrophil activation was assessed by measurement of secreted azurophilic granule protein resistin and profiling of the secretome, using mass spectrometry. RESULTS: Pneumococci are potent inducers of neutrophil degranulation. Pneumolysin was identified as a major trigger of neutrophil activation. This process is partially lysis independent and inhibited by ATP. Pneumolysin and ATP interact with each other in the extracellular space leading to reduced neutrophil activation. Proteome analyses of the neutrophil secretome confirmed that ATP inhibits pneumolysin-dependent neutrophil activation. CONCLUSIONS: Our findings suggest that despite its cytolytic activity, pneumolysin serves as a potent neutrophil activating factor. Extracellular ATP mitigates pneumolysin-induced neutrophil activation.


Assuntos
Trifosfato de Adenosina/metabolismo , Ativação de Neutrófilo/efeitos dos fármacos , Infecções Pneumocócicas/metabolismo , Estreptolisinas/efeitos adversos , Proteínas de Bactérias/efeitos adversos , Morte Celular , Humanos , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Streptococcus pneumoniae
9.
Environ Microbiol ; 22(8): 3266-3286, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32419322

RESUMO

The Gram-positive bacterium Bacillus subtilis is frequently exposed to hyperosmotic conditions. In addition to the induction of genes involved in the accumulation of compatible solutes, high salinity exerts widespread effects on B. subtilis physiology, including changes in cell wall metabolism, induction of an iron limitation response, reduced motility and suppression of sporulation. We performed a combined whole-transcriptome and proteome analysis of B. subtilis 168 cells continuously cultivated at low or high (1.2 M NaCl) salinity. Our study revealed significant changes in the expression of more than one-fourth of the protein-coding genes and of numerous non-coding RNAs. New aspects in understanding the impact of high salinity on B. subtilis include a sustained low-level induction of the SigB-dependent general stress response and strong repression of biofilm formation under high-salinity conditions. The accumulation of compatible solutes such as glycine betaine aids the cells to cope with water stress by maintaining physiologically adequate levels of turgor and also affects multiple cellular processes through interactions with cellular components. Therefore, we additionally analysed the global effects of glycine betaine on the transcriptome and proteome of B. subtilis and revealed that it influences gene expression not only under high-salinity, but also under standard growth conditions.


Assuntos
Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Betaína/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Proteoma , Salinidade , Cloreto de Sódio/farmacologia
10.
J Cell Physiol ; 234(7): 10111-10122, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30575044

RESUMO

Resident cardiac progenitor cells (CPCs) have gained attention in cardiac regenerative medicine primarily due to their paracrine activity. In our current study we determined the role of pathological conditions such as heart failure on the autocrine-paracrine action of stem cell antigen-1 (Sca-1) expressing CPC. This comparative secretome profiling of Sca-1+ cells derived from transgenic heart failure (αMHC-cyclin-T1/Gαq overexpression [Cyc] cells) versus healthy (wild-type [Wt] cells) mice, achieved via mass-spectrometric quantification, enabled the identification of over 700 proteins. Our results demonstrate that the heart failure milieu caused a 2-fold enrichment of extracellular matrix proteins (ECM) like biglycan, versican, collagen XII, and angiogenic factors like heparan sulfate proteoglycan 2, plasminogen activator inhibitor 1 in the secretome. We further elucidated the direct influence of the secretome on the functional behavior of Sca-1 + cells via in vitro tube forming assay. Secreted factors present in the diseased milieu induced tube formation in Cyc cells (1.7-fold; p < 0.01) when compared with Wt cells after 24 hr of exposure. The presence of conditioned media moderately increased the proliferation of Cyc cells but had a more pronounced effect on Wt cells. Overall, these findings revealed global modifications in the secretory activity of adult Sca-1 + cells in the heart failure milieu. The secretion of ECM proteins and angiogenic factors, which are crucial for cardiac remodeling and recovery, was notably enriched in the supernatant of Cyc cells. Thus, during heart failure the microenvironment of Sca-1 + cells might favor angiogenesis and proliferation suggesting their potential to recover the damaged heart.


Assuntos
Insuficiência Cardíaca/metabolismo , Coração , Células-Tronco/metabolismo , Animais , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Neovascularização Fisiológica/fisiologia , Proteoma
11.
Anal Chem ; 91(12): 7729-7737, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31117406

RESUMO

The intracellular pathogen Salmonella enterica has evolved an array of traits for propagation and invasion of the intestinal layers. It remains largely elusive how Salmonella adjusts its metabolic states to survive inside immune host cells. In this study, single-cell Raman biotechnology combined with deuterium isotope probing (Raman-DIP) have been applied to reveal metabolic changes of the typhoidal Salmonella Typhi Ty2, the nontyphoidal Salmonella Typhimurium LT2, and a clinical isolate Typhimurium D23580. By initially labeling the Salmonella strains with deuterium, we employed reverse labeling to track their metabolic changes in the time-course infection of THP-1 cell line, human monocyte-derived dendritic cells (MoDCs) and macrophages (Mf). We found that, in comparison with a noninvasive serovar, the invasive Salmonella strains Ty2 and D23580 have downregulated metabolic activity inside human macrophages and dendritic cells and used lipids as alternative carbon source, perhaps a strategy to escape from the host immune response. Proteomic analysis using high sensitivity mass spectrometry validated the findings of Raman-DIP analysis.


Assuntos
Macrófagos/microbiologia , Metaboloma , Salmonella typhi/metabolismo , Análise Espectral Raman/métodos , Linhagem Celular , Deutério/química , Deutério/metabolismo , Regulação para Baixo , Humanos , Marcação por Isótopo , Macrófagos/citologia , Macrófagos/metabolismo , Análise de Componente Principal , Análise de Célula Única
12.
J Proteome Res ; 16(6): 2273-2281, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28481548

RESUMO

Whole saliva is gaining more and more attention as a diagnostic tool to study disease-specific changes in human subjects. Prior to the actual disease-related analyses, it is important to understand the influence of various demographic variables and coupled phenotypes on salivary protein signatures. In a cross-sectional approach, we analyzed the influence of age, sex, body mass index (BMI), smoking, and education on salivary protein signatures in whole saliva samples of 187 individuals. Subjects were randomly selected from the population-based Study of Health in Pomerania (SHIP-Trend). Stimulated whole saliva was collected, and proteins were precipitated and proteolytically digested. Samples were analyzed by label-free tandem mass spectrometry. Of the 602 human proteins identified in at least 40% of the saliva samples, we used 304 proteins, which could be identified with at least two unique peptides, for statistical analyses. Univariate and multivariate linear models were used to reveal associations with the phenotypes. The largest number of proteins was associated with smoking status. Moreover, age had a distinct influence on the salivary protein composition. The study discloses the influence of common phenotypes on the salivary protein pattern of human subjects. These results should be considered when studying disease-related proteome signatures in saliva.


Assuntos
Fatores Etários , Proteoma/análise , Proteínas e Peptídeos Salivares/análise , Fumar , Adulto , Idoso , Índice de Massa Corporal , Estudos Transversais , Educação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Espectrometria de Massas em Tandem , Adulto Jovem
13.
Proteomics ; 16(20): 2667-2677, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27324828

RESUMO

Staphylococcus aureus is a frequent commensal but also a dangerous pathogen, causing many forms of infection ranging from mild to life-threatening conditions. Among its virulence factors are lipoproteins, which are anchored in the bacterial cell membrane. Lipoproteins perform various functions in colonization, immune evasion, and immunomodulation. These proteins are potent activators of innate immune receptors termed Toll-like receptors 2 and 6. This study addressed the specific B-cell and T-cell responses directed to lipoproteins in human S. aureus carriers and non-carriers. 2D immune proteomics and ELISA approaches revealed that titers of antibodies (IgG) binding to S. aureus lipoproteins were very low. Proliferation assays and cytokine profiling data showed only subtle responses of T cells; some lipoproteins did not elicit proliferation. Hence, the robust activation of the innate immune system by S. aureus lipoproteins does not translate into a strong adaptive immune response. Reasons for this may include inaccessibility of lipoproteins for B cells as well as ineffective processing and presentation of the antigens to T cells.


Assuntos
Imunidade Adaptativa , Linfócitos B/imunologia , Proteínas de Bactérias/imunologia , Lipoproteínas/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Linfócitos T/imunologia , Adulto , Linfócitos B/microbiologia , Células Cultivadas , Citocinas/imunologia , Feminino , Regulação da Expressão Gênica , Voluntários Saudáveis , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Proteoma/imunologia , Proteômica , Infecções Estafilocócicas/microbiologia , Linfócitos T/microbiologia , Fatores de Virulência/imunologia , Adulto Jovem
14.
Front Immunol ; 15: 1352704, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895118

RESUMO

Background: Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disease with skin barrier defects and a misdirected type 2 immune response against harmless antigens. The skin microbiome in AD is characterized by a reduction in microbial diversity with a dominance of staphylococci, including Staphylococcus epidermidis (S. epidermidis). Objective: To assess whether S. epidermidis antigens play a role in AD, we screened for candidate allergens and studied the T cell and humoral immune response against the extracellular serine protease (Esp). Methods: To identify candidate allergens, we analyzed the binding of human serum IgG4, as a surrogate of IgE, to S. epidermidis extracellular proteins using 2-dimensional immunoblotting and mass spectrometry. We then measured serum IgE and IgG1 binding to recombinant Esp by ELISA in healthy and AD individuals. We also stimulated T cells from AD patients and control subjects with Esp and measured the secreted cytokines. Finally, we analyzed the proteolytic activity of Esp against IL-33 and determined the cleavage sites by mass spectrometry. Results: We identified Esp as the dominant candidate allergen of S. epidermidis. Esp-specific IgE was present in human serum; AD patients had higher concentrations than controls. T cells reacting to Esp were detectable in both AD patients and healthy controls. The T cell response in healthy adults was characterized by IL-17, IL-22, IFN-γ, and IL-10, whereas the AD patients' T cells lacked IL-17 production and released only low amounts of IL-22, IFN-γ, and IL-10. In contrast, Th2 cytokine release was higher in T cells from AD patients than from healthy controls. Mature Esp cleaved and activated the alarmin IL-33. Conclusion: The extracellular serine protease Esp of S. epidermidis can activate IL-33. As an antigen, Esp elicits a type 2-biased antibody and T cell response in AD patients. This suggests that S. epidermidis can aggravate AD through the allergenic properties of Esp.


Assuntos
Dermatite Atópica , Imunoglobulina E , Serina Proteases , Staphylococcus epidermidis , Humanos , Staphylococcus epidermidis/imunologia , Dermatite Atópica/imunologia , Dermatite Atópica/microbiologia , Serina Proteases/imunologia , Serina Proteases/metabolismo , Adulto , Masculino , Feminino , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Proteínas de Bactérias/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Citocinas/metabolismo , Citocinas/imunologia , Linfócitos T/imunologia , Alérgenos/imunologia , Interleucina-33/imunologia , Pessoa de Meia-Idade
15.
Appl Microbiol Biotechnol ; 97(11): 5043-53, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23400446

RESUMO

The phenol-degrading yeast Trichosporon mucoides can oxidize and detoxify biarylic environmental pollutants such as dibenzofuran, diphenyl ether and biphenyl by ring cleavage. The degradation pathways are well investigated, but the enzymes involved are not. The high similarity of hydroxylated biphenyl derivatives and phenol raised the question if the enzymes of the phenol degradation are involved in ring cleavage or whether specific enzymes are necessary. Purification of enzymes from T. mucoides with catechol cleavage activity demonstrated the existence of three different enzymes: a classical catechol-1,2-dioxygenase (CDO), not able to cleave the aromatic ring system of 3,4-dihydroxybiphenyl, and two novel enzymes with a high affinity towards 3,4-dihydroxybiphenyl. The comparison of the biochemical characteristics and mass spectrometric sequence data of these three enzymes demonstrated that they have different substrate specificities. CDO catalyzes the ortho-cleavage of dihydroxylated monoaromatic compounds, while the two novel enzymes carry out a similar reaction on biphenyl derivatives. The ring fission of 3,4-dihydroxybiphenyl by the purified enzymes results in the formation of (5-oxo-3-phenyl-2,5-dihydrofuran-2-yl)acetic acid. These results suggest that the ring cleavage enzymes catalyzing phenol degradation are not involved in the ring cleavage of biarylic compounds by this yeast, although some intermediates of the phenol metabolism may function as inducers.


Assuntos
Poluentes Ambientais/metabolismo , Hidrocarbonetos Cíclicos/metabolismo , Trichosporon/metabolismo , Biotransformação , Enzimas/química , Enzimas/isolamento & purificação , Enzimas/metabolismo , Espectrometria de Massas , Oxirredução , Especificidade por Substrato , Trichosporon/enzimologia
16.
Microbiol Spectr ; 11(6): e0177823, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37819116

RESUMO

IMPORTANCE: In the expanding market of recombinant proteins, microbial cell factories such as Bacillus subtilis are key players. Microbial cell factories experience secretion stress during high-level production of secreted proteins, which can negatively impact product yield and cell viability. The CssRS two-component system and CssRS-regulated quality control proteases HtrA and HtrB play critical roles in the secretion stress response. HtrA has a presumptive dual function in protein quality control by exerting both chaperone-like and protease activities. However, its potential role as a chaperone has not been explored in B. subtilis. Here, we describe for the first time the beneficial effects of proteolytically inactive HtrA on α-amylase yields and overall bacterial fitness.


Assuntos
Proteínas de Bactérias , Peptídeo Hidrolases , Peptídeo Hidrolases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Chaperonas Moleculares/metabolismo
17.
J Proteome Res ; 11(8): 3947-54, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22702956

RESUMO

Protein degradation by the ubiquitin proteasome system ensures controlled degradation of structural proteins, signaling mediators, and transcription factors. Inhibition of proteasome function by specific proteasome inhibitors results in dose-dependent cellular effects ranging from induction of apoptosis to protective stress responses. The present study seeks to identify nuclear regulators mediating the protective stress response to low dose proteasome inhibition. Primary human endothelial cells were treated with low doses of the proteasome inhibitor MG132 for 2 h, and proteomic analysis of nuclear extracts was performed. Using a 2-D differential in gel electrophoresis (DIGE) approach, we identified more than 24 splice factors to be differentially regulated by low dose proteasome inhibition. In particular, several isoforms of hnRNPA1 were shown to be increased, pointing toward altered posttranslational modification of hnRNPA1 upon proteasome inhibition. Elevated levels of splice factors were associated with a different alternative splicing pattern in response to proteasome inhibition as determined by Affymetrix exon array profiling. Of note, we observed alternative RNA processing for stress associated genes such as caspases and heat shock proteins. Our study provides first evidence that low dose proteasome inhibition affects posttranscriptional regulation of splice factors and early alternative splicing events.


Assuntos
Processamento Alternativo/efeitos dos fármacos , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Leupeptinas/farmacologia , Inibidores de Proteassoma/farmacologia , Células Cultivadas , Éxons , Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Ribonucleoproteína Nuclear Heterogênea A1 , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Cultura Primária de Células , Complexo de Endopeptidases do Proteassoma/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteoma/genética , Proteoma/metabolismo , Processamento Pós-Transcricional do RNA/efeitos dos fármacos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
18.
J Proteome Res ; 11(4): 2316-30, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22409352

RESUMO

Aaptamine is a marine compound isolated from the sponge Aaptos aaptos showing antiproliferative properties via an undefined mode of action. We analyzed the effects of aaptamine treatment on the proliferation and protein expression of the pluripotent human embryonal carcinoma cell line NT2. Effects on proliferation, cell cycle distribution, and induction of apoptosis were analyzed. At lower concentrations, including the IC50 of 50 µM, aaptamine treatment resulted in a G2/M phase cell cycle arrest, whereas at higher concentrations, induction of apoptosis was seen. Differentially expressed proteins were assessed by 2D-PAGE and mass spectrometry, followed by verification and analysis of protein modifications of the most significantly up- and down-regulated proteins. Aaptamine treatment at the IC50 for 48 h resulted in alteration of 10 proteins, of which five each showed up- and down-regulation. Changes in the 2D map were frequently noticed as a result of post-transcriptional modifications, e.g., of the hypusine modification of the eukaryotic initiation factor 5A (eIF5A). Observed alterations such as increased expression of CRABP2 and hypusination of eIF5A have previously been identified during differentiation of pluripotent cells. For the first time, we describe changes in protein expression caused by aaptamine, providing valuable information regarding the mode of action of this compound.


Assuntos
Antineoplásicos/farmacologia , Naftiridinas/farmacologia , Neoplasias Embrionárias de Células Germinativas/química , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Proteoma/efeitos dos fármacos , Sequência de Aminoácidos , Produtos Biológicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletroforese em Gel Bidimensional , Células HEK293 , Humanos , Lisina/análogos & derivados , Lisina/metabolismo , Dados de Sequência Molecular , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas/análise , Proteínas/genética , Proteínas/metabolismo , Proteoma/análise , Proteoma/genética , Proteoma/metabolismo , Proteômica/métodos , Proteínas de Ligação a RNA/metabolismo , Reprodutibilidade dos Testes , Fator de Iniciação de Tradução Eucariótico 5A
19.
J Oral Microbiol ; 14(1): 2138251, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338832

RESUMO

Background: Dental plaque consists of a diverse microbial community embedded in a complex structure of exopolysaccharides. Dental biofilms form a natural barrier against pathogens but lead to oral diseases in a dysbiotic state. Objective: Using a metaproteome approach combined with a standard plaque-regrowth study, this pilot study examined the impact of different concentrations of lactoperoxidase (LPO) on early plaque formation, and active biological processes. Design: Sixteen orally healthy subjects received four local treatments as a randomized single-blind study based on a cross-over design. Two lozenges containing components of the LPO-system in different concentrations were compared to a placebo and Listerine®. The newly formed dental plaque was analyzed by mass spectrometry (nLC-MS/MS). Results: On average 1,916 metaproteins per sample were identified, which could be assigned to 116 genera and 1,316 protein functions. Listerine® reduced the number of metaproteins and their relative abundance, confirming the plaque inhibiting effect. The LPO-lozenges triggered mainly higher metaprotein abundances of early and secondary colonizers as well as bacteria associated with dental health but also periodontitis. Functional information indicated plaque biofilm growth. Conclusion: In conclusion, the mechanisms on plaque biofilm formation of Listerine® and the LPO-system containing lozenges are different. In contrast to Listerine®, the lozenges led to a higher bacterial diversity.

20.
Sci Rep ; 12(1): 7569, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534617

RESUMO

The tegument, as the surface layer of adult male and female Schistosoma spp. represents the protective barrier of the worms to the hostile environment of the host bloodstream. Here we present the first comparative analysis of sex-specific tegument proteins of paired or virgin Schistosoma mansoni. We applied a new and highly sensitive workflow, allowing detection of even low abundance proteins. Therefore, a streptavidin-biotin affinity purification technique in combination with single pot solid-phase enhanced sample preparation was established for subsequent LC-MS/MS analysis. We were able to identify 1519 tegument proteins for male and female virgin and paired worms and categorized them by sex. Bioinformatic analysis revealed an involvement of female-specific tegument proteins in signaling pathways of cellular processes and antioxidant mechanisms. Male-specific proteins were found to be enriched in processes linked to phosphorylation and signal transduction. This suggests a task sharing between the sexes that might be necessary for survival in the host. Our datasets provide a basis for further studies to understand and ultimately decipher the strategies of the two worm sexes to evade the immune system.


Assuntos
Proteoma , Schistosoma mansoni , Animais , Cromatografia Líquida , Feminino , Proteínas de Helminto/metabolismo , Masculino , Proteoma/metabolismo , Schistosoma mansoni/metabolismo , Espectrometria de Massas em Tandem
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