Despite the significance of Alzheimer’s disease, link between metal-associated amyloid-β (metal–Aβ) and disease etiology remains unclear. To elucidate this relationship, chemical tools capable specifically targeting modulating metal–Aβ species are necessary, along with a fundamental understanding their mechanism at molecular level. Herein, we investigated compared interactions reactivities green tea extract, (−)-epigallocatechin-3-gallate [(2 R ,3...

Folded or not? Ion mobility–mass spectrometry investigation of an activated macromolecular protein complex lends insight into the structures intermediates formed in dissociation process. The ions human tetrameric transthyretin populate partially folded intermediate states (see picture; subunits blue, unfolded red) prior to dissociation. Supporting information for this article is available on WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z702161_s.pdf from author. Please note:...

Tandem mass spectrometry (MS) of large protein complexes has proven to be capable assessing the stoichiometry, connectivity, and structural details multiprotein assemblies. While utility tandem MS is without question, a deeper understanding mechanism complex dissociation will undoubtedly drive technology into new areas enhanced information content. We present here systematic analysis charge state dependent decay noncovalently associated human transthyretin, generated by collision-induced...

High-accuracy, high-resolution ion mobility measurements enable a vast array of important contemporary applications in biological chemistry. With the recent advent both new, widely available commercial instrumentation and also new calibration datasets tailored for aforementioned instrumentation, possibilities extending such high performance to diverse set have never been greater. Here, we assess characteristics second-generation traveling-wave separator, focusing on those figures merit that...

Current challenges in the field of structural genomics point to need for new tools and technologies obtaining structures macromolecular protein complexes. Here, we present an integrative computational method that uses molecular modelling, ion mobility-mass spectrometry (IM-MS) incomplete atomic structures, usually from X-ray crystallography, generate models subunit architecture We begin by analyzing complexes using IM-MS, taking measurements both intact sub-complexes are generated solution....

The combination of ion mobility separation with mass spectrometry is an emergent and powerful structural biology tool, capable simultaneously assessing the structure, topology, dynamics, composition large protein assemblies within complex mixtures. An integral part mobility–mass measurement ionization intact multiprotein complexes their removal from bulk solvent. This process, during which a substantial portion structure organization likely to be preserved, imposes foreign environment on...

The discovery of activation state dependent kinase inhibitors, which bind specifically to the inactive conformation protein, is considered be a promising pathway improved cancer treatments. Identifying such inhibitors challenging, however, because they can have Kd values similar molecules known inhibit function by interacting with active form. Further, while inhibitor induced changes within tertiary structure are significant, few technologies able correctly assign binding modes in...

Transthyretin (TTR) is a plasma hormone carrier protein associated with hereditary and senile forms of systemic amyloid disease, wherein slow tetramer disassembly thought to be an obligatory step. Plasma transport retinol carried out exclusively by the retinol-binding (RBP), through complexation transthyretin. Using mass spectrometry examine subunit exchange dynamics, we find that stabilizes quaternary structure transthyretin, its interactions RBP, reducing rate transthyretin ∼17-fold...

Characterizing intact multiprotein complexes in terms of both their mass and size by ion mobility-mass spectrometry is becoming an increasingly important tool for structural biology. Furthermore, the charge states protein can dramatically influence information content gas-phase measurements performed. Specifically, complex state has a demonstrated upon conformation, resolution, mobility dissociation properties assemblies collisional activation. Here we present first comparison charge-reduced...

Metal ions associated with amyloid-β (Aβ) peptides have been suggested to be involved in the development of Alzheimer's disease (AD), but this remains unclear and controversial. Some attempts rationally design or select small molecules structural moieties for metal chelation Aβ interaction (i.e., bifunctionality) made gain a better understanding hypothesis. In order contribute these efforts, four synthetic flavonoid derivatives FL1–FL4 were selected according principles bifunctionality their...

Recently, small peptides have been shown to modulate aggregation and toxicity of the amyloid-β protein (Aβ). As such, these new scaffolds may help discover a class biotherapeutics useful in treatment Alzheimer's disease. Many inhibitory peptide sequences derived from natural sources or Aβ itself (e.g., C-terminal fragments). In addition, much earlier work indicates that tachykinins, broad neuropeptides, display neurotrophic properties, presumably through direct interactions with either its...

The ribosomal stalk complex binds and recruits translation factors to the ribosome during protein biosynthesis. In Escherichia coli is composed of L10 four copies L7/L12. Despite crucial role stalk, mechanistic details L7/L12 subunit exchange are not established. By incubating isotopically labeled intact ribosomes with their unlabeled counterparts we monitored labile proteins by recording mass spectra as a function time. On basis kinetic analysis, proposed mechanism whereby proceeds via...

Gefaltet oder nicht gefaltet? Messungen der Ionenbeweglichkeit und Massenspektrometrie eines aktivierten Proteinkomplexes geben einen Einblick in die Strukturen Dissoziationsintermediate. Die Ionen von humanem tetramerem Transthyretin nehmen vor Dissoziation partiell gefaltete Zwischenstufen ein (siehe Bild; Untereinheiten: blau, entfaltete rot). Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2001/2007/z702161_s.pdf or from author....

The role that water plays in the salt-based stabilization of proteins is central to our understanding protein biophysics. Ion hydration and ability ions alter surface tension are typically invoked, along with direct ion-protein binding, describe Hofmeister phenomena observed for experimentally, but relative influence these forces has been extraordinarily difficult measure directly. Recently, we have used gas-phase measurements large multiprotein complexes, using a combination innovative ion...

Kationische Helfer: Die massenspektrometrische Bestimmung von Proteinstrukturen kann durch Addition stabilisierender Kationen an das Gasphasenmolekül erleichtert werden. Dicht geladene (siehe Schema, grün) stabilisieren die Tertiärstruktur der Proteine und ermöglichen genaue Massebestimmung homo- heterogener Proteinkomplexe. bleiben während Analyse fest am Protein gebunden halten es so im gefalteten Zustand.

Quantitative analysis of antibody-drug conjugates (ADCs) involves cleavage ADCs into smaller analytes representing different components and subsequent measurements from multiple assays for a more comprehensive pharmacokinetic (PK) assessment. Multiple PK including the drug remaining conjugated to antibody (or antibody-conjugated drug, acDrug) total can be accessed simultaneously using multiplex assay by proteolytic digestion an ADC, if sites conjugation are homogeneous ADC linker is stable...