Nanoscale characterization of spider venom peptides by high resolution LC-MS/MS analysis

Comunicaciones a congreso

In-depth, comprenhensive mapping of the human seminal plasma proteome by a novel, iterative LC/MS/MS/database search workflow

Comunicaciones a congreso

High resolution targeted proteomics: biomarker discovery in a mouse transgenic model of myopathy

Comunicaciones a congreso

Separation of biologically relevant isomers on an Orbitrap mass spectrometer using high‐resolution drift tube ion mobility and varied drift gas mixtures

Rationale Atmospheric pressure drift tube ion mobility is a powerful addition to the Orbitrap mass spectrometer enabling direct separation of isomers. Apart from offering high resolving power in a compact design, it also facilitates optimization of the separation gas, as shown here for a series of biologically relevant isomer pairs.Methods An Excellims MA3100 High-Resolution Atmospheric Pressure Ion Mobility Spectrometer (HR-IMS) was coupled to a Thermo Scientific (TM) Q Exactive (TM) Focus hybrid quadrupole-Orbitrap (TM) mass spectrometer, using an Excellims Directspray (TM) Electrospray Ionization source and a gas mixture setup to provide various drift gases (air, CO2 and mixtures). This instrument combination was used to separate isomers of eight pairs of metabolites and gangliosides, optimizing drift gas conditions for best separation of each set.Results All but one of the isomers pairs provided could be partially or fully separated by the HR-IMS-MS combination using ion mobility drift times. About half of the separated compounds showed significantly better analytical separation when analyzed in a mixture of CO2 and air rather than air or CO2 alone. Resolving power of up to 102 was achieved using the 10 cm atmospheric drift tube ion mobility add-on for the Orbitrap mass spectrometer.Conclusions The present analysis demonstrates the usefulness of using atmospheric drift tube IMS on an Orbitrap mass spectrometer to characterize the isomeric composition of samples. It also highlights the potential benefits of being able to quickly optimize the drift gas composition to selectively maximize the mobility difference for isomer separation

A Combinatorial omics approach to identify testicular germline markers in the human seminal plasma proteome.

International audienc

Structural venomics reveals evolution of a complex venom by duplication and diversification of an ancient peptide-encoding gene

Spiders are one of the most successful venomous animals, with more than 48,000 described species. Most spider venoms are dominated by cysteine-rich peptides with a diverse range of pharmacological activities. Some spider venoms contain thousands of unique peptides, but little is known about the mechanisms used to generate such complex chemical arsenals. We used an integrated transcriptomic, proteomic, and structural biology approach to demonstrate that the lethal Australian funnel-web spider produces 33 superfamilies of venom peptides and proteins. Twenty-six of the 33 superfamilies are disulfide-rich peptides, and we show that 15 of these are knottins that contribute >90% of the venom proteome. NMR analyses revealed that most of these disulfide-rich peptides are structurally related and range in complexity from simple to highly elaborated knottin domains, as well as double-knot toxins, that likely evolved from a single ancestral toxin gene