Native Top-Down Mass Spectrometry and Ion Mobility MS for Characterizing the Cobalt and Manganese Metal Binding of α-Synuclein Protein

Wongkongkathep, Piriya; Han, Jong Yoon; Choi, Tae Su; Yin, Sheng; Kim, Hugh I.; Loo, Joseph A.

doi:10.1007/s13361-018-2002-2

Cited by 64 publications

(84 citation statements)

References 83 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The compacting trends observed here were also observed in earlier studies, confirming our nESI-IM-MS results 7,45 . Alkali metal ions are known to interact almost exclusively with oxygen atoms in proteins, with a single negative charge as "ligand" (besides additional water molecules which are not retained in ESI mass spectra) 63 .…”

Section: Discussionsupporting

confidence: 92%

“…This illustrates the difficulty of predicting protein-metal ion interactions, particularly for a protein with an undefined structure and the need for more insight into these molecular mechanisms. There are also promising top-down MS/MS fragmentation approaches which can identify binding sites of metal ions in proteins, namely electron transfer dissociation (ETD), electron capture dissociation (ECD) and ultraviolet photodissociation (UVPD), but the challenge here is that the fragment-level binding data should be linked with a specific conformational state of the protein 45,80 .…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Metal ions shape α-synuclein

Moons

Konijnenberg

Mensch

et al. 2020

Sci Rep

View full text Add to dashboard Cite

α-Synuclein is an intrinsically disordered protein that can self-aggregate and plays a major role in Parkinson’s disease (PD). Elevated levels of certain metal ions are found in protein aggregates in neurons of people suffering from PD, and environmental exposure has also been linked with neurodegeneration. Importantly, cellular interactions with metal ions, particularly Ca2+, have recently been reported as key for α-synuclein’s physiological function at the pre-synapse. Here we study effects of metal ion interaction with α-synuclein at the molecular level, observing changes in the conformational behaviour of monomers, with a possible link to aggregation pathways and toxicity. Using native nano-electrospray ionisation ion mobility-mass spectrometry (nESI-IM-MS), we characterize the heterogeneous interactions of alkali, alkaline earth, transition and other metal ions and their global structural effects on α-synuclein. Different binding stoichiometries found upon titration with metal ions correlate with their specific binding affinity and capacity. Subtle conformational effects seen for singly charged metals differ profoundly from binding of multiply charged ions, often leading to overall compaction of the protein depending on the preferred binding sites. This study illustrates specific effects of metal coordination, and the associated electrostatic charge patterns, on the complex structural space of the intrinsically disordered protein α-synuclein.

show abstract

Section: Discussionsupporting

confidence: 92%

Section: Discussionmentioning

confidence: 99%

Metal ions shape α-synuclein

Moons

Konijnenberg

Mensch

et al. 2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Fragmentation appears to be limited to the flexible termini regions (Figure 3). Other intrinsically disordered proteins, such as α-synuclein, allow for much higher yields for top-down MS, up to 90% sequence coverage [47]. The data shown for the 103-residue 4R-repeat domain fragment shows 61% sequence coverage (62 interresidue cleavages out of 102 total interresidue bonds) for the apo-form.…”

Section: Resultsmentioning

confidence: 99%

Native Top-Down Mass Spectrometry and Ion Mobility Spectrometry of the Interaction of Tau Protein with a Molecular Tweezer Assembly Modulator

Nshanian

Lantz

Wongkongkathep

et al. 2018

J. Am. Soc. Mass Spectrom.

Self Cite

View full text Add to dashboard Cite

Native top-down mass spectrometry (MS) and ion mobility spectrometry (IMS) were applied to characterize the interaction of a molecular tweezer assembly modulator, CLR01, with tau, a protein believed to be involved in a number of neurodegenerative disorders, including Alzheimer's disease. The tweezer CLR01 has been shown to inhibit aggregation of amyloidogenic polypeptides without toxic side effects. ESI-MS spectra for different forms of tau protein (full-length, fragments, phosphorylated, etc.) in the presence of CLR01 indicate a primary binding stoichiometry of 1:1. The relatively high charging of the protein measured from non-denaturing solutions is typical of intrinsically disordered proteins, such as tau. Top-down mass spectrometry using electron capture dissociation (ECD) is a tool used to determine not only the sites of post-translational modifications but also the binding site(s) of non-covalent interacting ligands to biomolecules. The intact protein and the protein-modulator complex were subjected to ECD-MS to obtain sequence information, map phosphorylation sites, and pinpoint the sites of inhibitor binding. The ESI-MS study of intact tau proteins indicates that top-down MS is amenable to the study of various tau isoforms and their post-translational modifications (PTMs). The ECD-MS data point to a CLR01 binding site in the microtubule-binding region of tau, spanning residues K294-K331, which includes a six-residue nucleating segment PHF6 (VQIVYK) implicated in aggregation. Furthermore, ion mobility experiments on the tau fragment in the presence of CLR01 and phosphorylated tau reveal a shift towards a more compact structure. The mass spectrometry study suggests a picture for the molecular mechanism of the modulation of protein-protein interactions in tau by CLR01. Graphical Abstract ᅟ.

show abstract

“…Since the development of ExD and photodissociation techniques, metal ions can be more reliably pinpointed on peptides and proteins. Metal ion binding sites have been identied on native peptide and protein monomers such as amyloid b, 158 a-synuclein, 159,160 and carbonic anhydrase 161 with ECD, as well as native protein complexes such as alcohol dehydrogenase. 153,162 Similarly, UVPD is also effective in determining metal binding sites as shown in model metalloproteins including staphylococcal nuclease, azurin, and calmodulin.…”

Section: Native Mass Spectrometry Of Protein Complexesmentioning

confidence: 99%