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1.
Cell Syst ; 12(8): 780-794.e7, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34139154

RESUMO

COVID-19 is highly variable in its clinical presentation, ranging from asymptomatic infection to severe organ damage and death. We characterized the time-dependent progression of the disease in 139 COVID-19 inpatients by measuring 86 accredited diagnostic parameters, such as blood cell counts and enzyme activities, as well as untargeted plasma proteomes at 687 sampling points. We report an initial spike in a systemic inflammatory response, which is gradually alleviated and followed by a protein signature indicative of tissue repair, metabolic reconstitution, and immunomodulation. We identify prognostic marker signatures for devising risk-adapted treatment strategies and use machine learning to classify therapeutic needs. We show that the machine learning models based on the proteome are transferable to an independent cohort. Our study presents a map linking routinely used clinical diagnostic parameters to plasma proteomes and their dynamics in an infectious disease.


Assuntos
Biomarcadores/análise , COVID-19/patologia , Progressão da Doença , Proteoma/fisiologia , Fatores Etários , Contagem de Células Sanguíneas , Gasometria , Ativação Enzimática , Humanos , Inflamação/patologia , Aprendizado de Máquina , Prognóstico , Proteômica , SARS-CoV-2/imunologia
2.
Nat Biotechnol ; 39(7): 846-854, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33767396

RESUMO

Accurate quantification of the proteome remains challenging for large sample series and longitudinal experiments. We report a data-independent acquisition method, Scanning SWATH, that accelerates mass spectrometric (MS) duty cycles, yielding quantitative proteomes in combination with short gradients and high-flow (800 µl min-1) chromatography. Exploiting a continuous movement of the precursor isolation window to assign precursor masses to tandem mass spectrometry (MS/MS) fragment traces, Scanning SWATH increases precursor identifications by ~70% compared to conventional data-independent acquisition (DIA) methods on 0.5-5-min chromatographic gradients. We demonstrate the application of ultra-fast proteomics in drug mode-of-action screening and plasma proteomics. Scanning SWATH proteomes capture the mode of action of fungistatic azoles and statins. Moreover, we confirm 43 and identify 11 new plasma proteome biomarkers of COVID-19 severity, advancing patient classification and biomarker discovery. Thus, our results demonstrate a substantial acceleration and increased depth in fast proteomic experiments that facilitate proteomic drug screens and clinical studies.


Assuntos
Proteômica/métodos , Espectrometria de Massas em Tandem , Arabidopsis/metabolismo , Biomarcadores/metabolismo , COVID-19/sangue , COVID-19/diagnóstico , Linhagem Celular , Humanos , Peptídeos/análise , Proteoma/análise , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Índice de Gravidade de Doença
3.
Cell Syst ; 11(1): 11-24.e4, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32619549

RESUMO

The COVID-19 pandemic is an unprecedented global challenge, and point-of-care diagnostic classifiers are urgently required. Here, we present a platform for ultra-high-throughput serum and plasma proteomics that builds on ISO13485 standardization to facilitate simple implementation in regulated clinical laboratories. Our low-cost workflow handles up to 180 samples per day, enables high precision quantification, and reduces batch effects for large-scale and longitudinal studies. We use our platform on samples collected from a cohort of early hospitalized cases of the SARS-CoV-2 pandemic and identify 27 potential biomarkers that are differentially expressed depending on the WHO severity grade of COVID-19. They include complement factors, the coagulation system, inflammation modulators, and pro-inflammatory factors upstream and downstream of interleukin 6. All protocols and software for implementing our approach are freely available. In total, this work supports the development of routine proteomic assays to aid clinical decision making and generate hypotheses about potential COVID-19 therapeutic targets.


Assuntos
Proteínas Sanguíneas/metabolismo , Infecções por Coronavirus/sangue , Pneumonia Viral/sangue , Proteômica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/isolamento & purificação , Biomarcadores/sangue , Proteínas Sanguíneas/análise , COVID-19 , Infecções por Coronavirus/classificação , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias/classificação , Pneumonia Viral/classificação , Pneumonia Viral/patologia , Pneumonia Viral/virologia , SARS-CoV-2 , Adulto Jovem
4.
Nat Methods ; 17(1): 41-44, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31768060

RESUMO

We present an easy-to-use integrated software suite, DIA-NN, that exploits deep neural networks and new quantification and signal correction strategies for the processing of data-independent acquisition (DIA) proteomics experiments. DIA-NN improves the identification and quantification performance in conventional DIA proteomic applications, and is particularly beneficial for high-throughput applications, as it is fast and enables deep and confident proteome coverage when used in combination with fast chromatographic methods.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Espectrometria de Massas/métodos , Redes Neurais de Computação , Proteoma/análise , Proteômica/métodos , Software , Zea mays/metabolismo , Células HeLa , Humanos , Especificidade da Espécie
5.
Cell Syst ; 7(3): 269-283.e6, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30195436

RESUMO

A challenge in solving the genotype-to-phenotype relationship is to predict a cell's metabolome, believed to correlate poorly with gene expression. Using comparative quantitative proteomics, we found that differential protein expression in 97 Saccharomyces cerevisiae kinase deletion strains is non-redundant and dominated by abundance changes in metabolic enzymes. Associating differential enzyme expression landscapes to corresponding metabolomes using network models provided reasoning for poor proteome-metabolome correlations; differential protein expression redistributes flux control between many enzymes acting in concert, a mechanism not captured by one-to-one correlation statistics. Mapping these regulatory patterns using machine learning enabled the prediction of metabolite concentrations, as well as identification of candidate genes important for the regulation of metabolism. Overall, our study reveals that a large part of metabolism regulation is explained through coordinated enzyme expression changes. Our quantitative data indicate that this mechanism explains more than half of metabolism regulation and underlies the interdependency between enzyme levels and metabolism, which renders the metabolome a predictable phenotype.


Assuntos
Fosfotransferases/genética , Saccharomyces cerevisiae/fisiologia , Deleção de Sequência/genética , Regulação Fúngica da Expressão Gênica , Técnicas de Inativação de Genes , Estudos de Associação Genética , Aprendizado de Máquina , Metaboloma , Microrganismos Geneticamente Modificados , Proteoma
6.
Proc Natl Acad Sci U S A ; 114(28): 7403-7407, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28652321

RESUMO

The evolutionary origins of metabolism, in particular the emergence of the sugar phosphates that constitute glycolysis, the pentose phosphate pathway, and the RNA and DNA backbone, are largely unknown. In cells, a major source of glucose and the large sugar phosphates is gluconeogenesis. This ancient anabolic pathway (re-)builds carbon bonds as cleaved in glycolysis in an aldol condensation of the unstable catabolites glyceraldehyde 3-phosphate and dihydroxyacetone phosphate, forming the much more stable fructose 1,6-bisphosphate. We here report the discovery of a nonenzymatic counterpart to this reaction. The in-ice nonenzymatic aldol addition leads to the continuous accumulation of fructose 1,6-bisphosphate in a permanently frozen solution as followed over months. Moreover, the in-ice reaction is accelerated by simple amino acids, in particular glycine and lysine. Revealing that gluconeogenesis may be of nonenzymatic origin, our results shed light on how glucose anabolism could have emerged in early life forms. Furthermore, the amino acid acceleration of a key cellular anabolic reaction may indicate a link between prebiotic chemistry and the nature of the first metabolic enzymes.


Assuntos
Frutosedifosfatos/metabolismo , Gluconeogênese , Gelo , Aminoácidos/química , Frutose-Bifosfato Aldolase/química , Glucose/química , Glicólise , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Via de Pentose Fosfato , Fosforilação , Fosfatos Açúcares/química , Temperatura , Fatores de Tempo
7.
J Sep Sci ; 38(8): 1334-43, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25645427

RESUMO

In this study, a novel method for the highly selective enrichment of phosphopeptides using erbium phosphate doped poly(glycidyl methacrylate/ethylene dimethacrylate) spin columns is presented. Erbium phosphate was synthesized by precipitation from boiling phosphoric acid and incubated overnight in erbium chloride solutions. The resulting powder was embedded in a monolithic poly(glycidyl methacrylate/ethylene dimethacrylate) polymer. The monolith was synthesized in a spin column by radical polymerization. Erbium phosphate demonstrated a high affinity and selectivity for phosphopeptides due to the strong interaction of trivalent erbium ions with the phosphate groups of phosphopeptides. The high selectivity and performance of the designed spin columns were demonstrated by successfully enriching phosphopeptides from tryptically digested protein mixtures containing the model phosphoproteins α- and ß-casein, bovine milk, and human saliva. By the implementation of several washing steps, unspecific components were removed and the enriched phosphopeptides were effectively eluted from the spin columns under alkaline conditions. The selective performance of the presented method was further demonstrated by the enrichment of two synthetic phosphopeptides, which were spiked in tryptically digested and dephosphorylated HeLa cell lysates at low ratios. Finally, the presented approach was compared to conventional phosphopeptide enrichment by titanium oxide and revealed higher recoveries for the erbium phosphate doped monoliths.


Assuntos
Érbio/química , Metacrilatos/química , Fosfatos/química , Fosfopeptídeos/química , Ácidos Polimetacrílicos/química , Sequência de Aminoácidos , Animais , Caseínas/química , Bovinos , Células HeLa , Humanos , Íons , Microscopia Eletrônica de Varredura , Leite/química , Dados de Sequência Molecular , Fosfoproteínas/química , Polímeros/química , Saliva/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Tripsina/química
8.
Mol Biosyst ; 11(1): 232-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25361442

RESUMO

Several bioanalytical enrichment techniques are based on the interactions of phosphopeptides with Ln(III) ions. In order to gain an improved understanding of these complexes and the respective ion-peptide interactions, hybrid quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) simulations of La(III) coordinating to the phosphopeptide VPQLEIVPNSpAEER were conducted. Simulations of di- as well as monoanionic phosphate groups were carried out. The La(III) ion and its first hydration layer, including the sidechain of the phosphoserine residue were treated quantum mechanically at RI-MP2/triple zeta level, whereas the remaining part of the system was treated with classical potentials. The simulation of the dianionic phosphopeptide revealed a 9-fold coordinated La(III) ion, with the phosphopeptide binding bi- as well as monodentate. The mean residence times (τ) of the first shell water molecules were 82 ps and 37 ps for the bi- and monodentate complexes, respectively, which is much higher compared to free La(III) in aqueous solution (τ=17 ps). The simulation of the monoanionic La(III)-phosphopeptide complex revealed a bidentate coordination throughout the 80 ps sampling period. An intramolecular hydrogen bond between the hydrogen of the phosphate group and the backbone was observed and a τ value of 14 ps was obtained, which is much lower as for the dianionic complex.


Assuntos
Lantânio/química , Simulação de Dinâmica Molecular , Fosfopeptídeos/química , Teoria Quântica , Modelos Moleculares , Conformação Molecular , Ligação Proteica
9.
J Phys Chem B ; 118(42): 12232-8, 2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-25301257

RESUMO

Immobilized metal ion affinity chromatography (IMAC) is an important chromatographic technique for biomolecules. In order to get a detailed understanding of the hydration of immobilized Fe(III), complexes of Fe(III) with methyl substituted iminodiacetate ([Fe(MSIDA)(H2O)3](+)) as well as with methyl substituted nitrilotriacetate ([Fe(MSNTA)(H2O)2]) were simulated in aqueous solutions with the quantum mechanical charge field molecular dynamics (QMCF MD) approach. The simulations were carried out at the Hartree-Fock (HF) level of theory, since cluster calculations at the HF, MP2, and B3LYP levels of theory showed that this method results in a good compromise between computational effort and accuracy. None of the coordinating water molecules were exchanged during the simulation period of 15 ps. The Fe-OH2O bond distances as well as the Fe-OH2O stretching motions differed among the coordinating water molecules, indicating different bond strengths. For the water molecules in the second hydration layer, mean residence times of 2.7 and 1.9 ps were obtained for [Fe(MSIDA)(H2O)3](+) and [Fe(MSNTA)(H2O)2], respectively. Furthermore, infrared measurements were carried out to characterize the most prominent bond features of aqueous Fe(III)-NTA and to discuss these results in conjunction with the computationally derived frequencies.

10.
Biomed Chromatogr ; 28(3): 412-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24097333

RESUMO

In this study a new type of immobilized metal ion affinity chromatography resin for the enrichment of carbohydrates and polyols was synthesized by radical polymerization reaction of vinyl phosphonic acid and 1,4-butandiole dimethacrylate using azo-bis-isobutyronitrile as radical initiator. Interaction between the chelated trivalent lanthanide ions and negatively charged hydroxyl groups of carbohydrates and polyols was observed by applying high pH values. The new method was evaluated by single standard solutions, mixtures of standards, honey and a more complex extract of Cynara scolymus. The washing step was accomplished by acetonitrile in excess volumes. Elution of enriched carbohydrates was successfully performed with deionized water. The subsequent analysis was carried out with matrix-free laser desorption/ionization-time of flight mass spectrometry involving a TiO2 -coated steel target, especially suitable for the measurement of low-molecular-weight substances. Quantitative analysis of the sugar alcohol xylitol as well as the determination of the maximal loading capacity was performed by gas chromatography in conjunction with mass spectrometric detection after chemical derivatization. In a parallel approach quantum mechanical geometry optimizations were performed in order to compare the coordination behavior of various trivalent lanthanide ions.


Assuntos
Carboidratos/isolamento & purificação , Cromatografia de Afinidade/métodos , Elementos da Série dos Lantanídeos/química , Polímeros/isolamento & purificação , Carboidratos/análise , Cynara scolymus/química , Cromatografia Gasosa-Espectrometria de Massas , Mel/análise , Limite de Detecção , Extratos Vegetais/química , Polímeros/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
J Phys Chem B ; 117(48): 15151-6, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24251538

RESUMO

Structural and dynamical properties of the erbium(III) ion in water have been obtained by means of ab initio quantum mechanical charge field molecular dynamics (QMCF-MD) simulations for the ground state and an excited state. The quality of the simulations has been monitored by recording UV/vis and Raman spectra of dilute solutions of ErCl3 and Er(NO3)3 in water and by comparison with EXAFS data from literature. Slight deviations between these data can be mainly attributed to relativistic effects, which are not sufficiently considered by the methodological framework. In both simulations, a mixture of coordination numbers eight and nine and a ligand exchange on the picosecond range are observed. The strength of the Er-ligand bond is considerably lower than that of trivalent transition metal ions but higher than that for La(III) and Ce(III) in aqueous solution. The main difference between ground state and excited state is the ligand exchange rate of the first shell. The second hydration shell is stable in both cases but with significantly different properties.

12.
Analyst ; 138(10): 2995-3004, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23552617

RESUMO

In this study, a new type of immobilized metal-ion affinity chromatography (IMAC) resin for the isolation of phosphopeptides was synthesized which is based on the specific interaction between phosphate groups and chelated lanthanide metal ions. In this regard trivalent lanthanum, holmium and erbium ions were chelated to a highly porous phosphonate polymer which was prepared by radical polymerization of vinylphosphonic acid (VPA) and divinylbenzene (DVB). The developed method was evaluated with peptide mixtures from digested standard proteins (α-casein, ß-casein and ovalbumin) as well as with bovine milk, egg white and a spiked HeLa cell lysate. Compared to the commonly used TiO2 approach, the presented method showed higher selectivity for phosphorylated peptides. This can be explained by the strong preference of trivalent lanthanide ions for phosphates with which they form very tight ionic bonds. Mono- and multiply phosphorylated peptides could be enriched and released in a single basic elution step, while non-phosphorylated peptides remained on the resin. Ab initio quantum mechanical energy minimizations of model complexes for polymer-ion-ligand interactions provided geometries, binding energies and charges which are discussed in conjunction with the observed experimental properties, leading to the most satisfying agreement. The presented lanthanide-IMAC resins represent promising affinity materials for the selective isolation of phosphopeptides from biological samples.


Assuntos
Quelantes/química , Cromatografia de Afinidade , Elementos da Série dos Lantanídeos/química , Fosfopeptídeos/isolamento & purificação , Quelantes/síntese química , Íons/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
13.
Analyst ; 138(10): 2897-905, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23529405

RESUMO

The basic idea of this study was to recover phosphopeptides after trypsin-assisted digestion of precipitated phosphoproteins using trivalent lanthanide ions. In the first step, phosphoproteins were extracted from the protein solution by precipitation with La(3+) and Ce(3+) ions, forming stable pellets. Additionally, the precipitated lanthanide-phosphoprotein complexes were suspended and directly digested on-pellet using trypsin. Non-phosphorylated peptides were released into the supernatants by enzymatic cleavage and phosphopeptides remained bound on the precipitated pellet. Further washing steps improved the removal of non-phosphorylated peptides. For the recovery of phosphopeptides the precipitated pellets were dissolved in 3.7% hydrochloric acid. The performance of this method was evaluated by several experiments using MALDI-TOF MS measurements and delivered the highest selectivity for phosphopeptides. This can be explained by the overwhelming preference of lanthanides for binding to oxygen-containing anions such as phosphates. The developed enrichment method was evaluated with several types of biological samples, including fresh milk and egg white. The uniqueness and the main advantages of the presented approach are the enrichment on the protein-level and the recovery of phosphopeptides on the peptide-level. This allows much easier handling, as the number of molecules on the peptide level is unavoidably higher, by complicating every enrichment strategy.


Assuntos
Elementos da Série dos Lantanídeos/metabolismo , Compostos Organometálicos/metabolismo , Fosfopeptídeos/análise , Fosfoproteínas/metabolismo , Tripsina/metabolismo , Elementos da Série dos Lantanídeos/química , Compostos Organometálicos/química , Fosfopeptídeos/metabolismo , Fosfoproteínas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
J Phys Chem Lett ; 4(9): 1502-6, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-26282305

RESUMO

The cis- and trans-bis(glycinato)copper(II) complexes in aqueous solution have been investigated by means of a combined theoretical and experimental approach. The conducted quantum mechanical charge field molecular dynamics (QMCF-MD) studies, being the first quantum mechanical simulations of organometallic complexes by this method, yielded accurate structural details of the investigated isomers as well as novel dynamic data, which has successfully been confirmed and extended by subsequent mid-infrared measurements. The spectroscopic results, critically assessed by adjacent multivariate data analysis, indicate an isomeric stability at ambient conditions, vanishing at elevated temperatures.

15.
Phys Chem Chem Phys ; 13(1): 224-9, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21103539

RESUMO

The four-times positively charged zirconium ion in aqueous solution was simulated, using an ab initio quantum mechanical charge field molecular dynamics approach. As no hydrolysis reaction occurred during the simulation time of 10 ps, the target of this study was the evaluation of the structure and dynamics of the monomeric hydrated zirconium(iv) ion. The ion forms three hydration shells. In the first hydration shell the ion is 8-fold coordinated with a maximum probability of the Zr-O distance at 2.25 Å. While no exchanges occurred between the first and second shell, the mean residence time of the water molecules in the second shell is 5.5 ps. A geometry of the first hydration shell in-between a bi-capped trigonal prism and a square antiprism was found and a Zr-O force constant of 188 N m(-1) was evaluated.


Assuntos
Simulação de Dinâmica Molecular , Teoria Quântica , Água/química , Zircônio/química , Estrutura Molecular
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