Monitoring mAb proteoforms in mouse plasma using an automated immunocapture combined with top-down and middle-down mass spectrometry.

Monoclonal antibodies (mAbs) have established themselves as the leading biopharmaceutical therapeutic modality. Once the developability of a mAb drug candidate has been assessed, an important step is to check its in vivo stability through pharmacokinetics (PK) studies. The gold standard is ligand-binding assay (LBA) and liquid chromatography-mass spectrometry (LC-MS) performed at the peptide level (bottom-up approach).

TDFragMapper: a visualization tool for evaluating experimental parameters in top-down proteomics.

Motivation: We present a new software-tool allowing an easy visualization of fragment ions and thus a rapid evaluation of key experimental parameters on the sequence coverage obtained for the MS/MS (tandem mass spectrometry) analysis of intact proteins. Our tool can process data obtained from various deconvolution and fragment assignment software.

Results: We demonstrate that TDFragMapper can rapidly highlight the experimental fragmentation parameters that are critical to the characterization of intact proteins of various size using top-down proteomics.

The ion-coupling mechanism of human excitatory amino acid transporters.

Excitatory amino acid transporters (EAATs) maintain glutamate gradients in the brain essential for neurotransmission and to prevent neuronal death. They use ionic gradients as energy source and co-transport transmitter into the cytoplasm with Na and H , while counter-transporting K to re-initiate the transport cycle. However, the molecular mechanisms underlying ion-coupled transport remain incompletely understood.

Advanced Cross-Linking Mass Spectrometry Platform to Characterize Proteome-Wide Protein Interactions.

Chemical cross-linking (XL) coupled to mass spectrometry (MS) has become a powerful approach to probe the structure of protein assemblies. Although most of the applications concerned purified complexes, latest developments focus on large-scale studies. Pushing in this direction, we developed an advanced cross-linking mass spectrometry platform to study the cellular interactome of living bacterial cells.