Solution-phase deuterium/hydrogen exchange at a specific residue using nozzle-skimmer and electron capture dissociation mass spectrometry.

Information about protein conformation can be obtained with hydrogen/deuterium exchange (HDX) mass spectrometry. The isotopic solution-phase exchange of specific amide hydrogen atoms can be followed using low-vacuum nozzle-skimmer collision-induced dissociation (CID). In this study, the nozzle-skimmer technique was complemented by electron capture dissociation (ECD) Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS).

Depletion of high-abundant proteins in body fluids prior to liquid chromatography fourier transform ion cyclotron resonance mass spectrometry.

Today, proteomics is an exciting approach to discover potential biomarkers of different disorders. One challenge with proteomics experiments is the wide concentration range of proteins in various tissues and body fluids. The most abundant component in human body fluids, human serum albumin (HSA), is present at concentrations corresponding to approximately 50% of the total protein content in, e.

Reproducibility of tryptic digestion investigated by quantitative fourier transform ion cyclotron resonance mass spectrometry.

In this study, the reproducibility of tryptic digestion of complex solutions was investigated using liquid chromatography Fourier transform ion cyclotron resonance (LC FT-ICR) mass spectrometry. Tryptic peptides, from human cerebrospinal fluid, (CSF) were labeled with Quantification-Using-Enhanced-Signal-Tags (QUEST)-markers, or 1-([H4]nicotinoyloxy)- and 1-([D4]nicotinoyloxy)-succinimide ester markers. The analysis was performed on abundant proteins with respect-to-intensity ratios and sequence coverage and obtained by comparing differently labeled components from one or different pools.

Cerebrospinal fluid protein patterns in neurodegenerative disease revealed by liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry.

This study demonstrates the power of a novel proteomic approach developed for the detection and identification of biological markers in body fluids. The goal was to observe alterations in the protein patterns of cerebrospinal fluid (CSF) related to amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder with unknown etiology. In the experiments, tryptic digests of CSF from patients and healthy controls were analyzed by on-line capillary liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry.

Electron capture dissociation Fourier transform ion cyclotron resonance mass spectrometry in the electron energy range 0-50 eV.

Electron capture dissociation (ECD) of polypeptide cations was obtained with pencil and hollow electron beams for both sidekick and gas-assisted dynamic ion trapping (GADT) using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) with an electrostatic ion transfer line. Increasing the number of trapped ions by multiple ICR trap loads using GADT improved the ECD sensitivity in comparison with sidekick ion trapping and ECD efficiency in comparison with single ion trap load by GADT. Furthermore, enhanced sensitivity made it possible to observe ECD in a wide range of electron energies (0-50 eV).

Peptide and protein characterization by high-rate electron capture dissociation Fourier transform ion cyclotron resonance mass spectrometry.

The analytical utility of the electron capture dissociation (ECD) technique, developed by McLafferty and co-workers, has substantially improved peptide and protein characterization using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The limitations of the first ECD implementations on commercial instruments were eliminated by the employment of low-energy electron-injection systems based on indirectly heated dispenser cathodes. In particular, the ECD rate and reliability were greatly increased, enabling the combination of ECD/FTICR-MS with on-line liquid separation techniques.

Quantitative analysis of tryptic protein mixtures using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry.

For the first time, quantitative analysis of tryptic protein mixtures, labeled with Quantification-Using-Enhanced-Signal-Tags (QUEST)-markers, were performed with electrospray ionization and a 9.4 T Fourier Transform Ion Cyclotron Resonance (FTICR) mass spectrometer. Coupling a High-Pressure Liquid Chromatography (HPLC) separation step prior to mass analysis resulted in an increased amount of identified labeled tryptic peptides.

Inter-molecular migration during collisional activation monitored by hydrogen/deuterium exchange FT-ICR tandem mass spectrometry.

The difficulty with integrating solution-phase hydrogen/deuterium exchange (HDX) and tandem mass spectrometry is that the energy added to cause fragmentation might promote gas-phase migration of the added deuterium atoms. Here, we compare the solution-phase HDX profiles generated from a- b- and y-type fragment ion series originating from capillary-skimmer dissociation. The isotopic distributions of fragments from the different fragment ion types were used to determine the isotopic state of the amide hydrogen within a specific residue.

Shifted-basis technique improves accuracy of peak position determination in Fourier transform mass spectrometry.

The present paper suggests a new algorithm for estimation of peak positions in FTMS spectra. It is shown theoretically and experimentally that the new technique yields superior results compared to the currently applied techniques, when the noise level is high and/or the peaks are located close to each other. Cases are presented where the deviation from the true mass could be mistaken for space charge effect, while the shift is in fact solely due to the shortcomings of the current techniques and can be corrected by applying the shifted-basis technique.

Localized changes in the structural stability of myoglobin upon adsorption onto silica particles, as studied with hydrogen/deuterium exchange mass spectrometry.

A new method is presented for monitoring the conformational stability of various parts of a protein that is physically adsorbed onto nanometer-sized silica particles. The method employs hydrogen/deuterium (H/D) exchange of amide hydrogens, a process that is extremely sensitive to structural features of proteins. The resulting mass increase is analyzed with Fourier transform ion cyclotron resonance (FTICR) mass spectrometry.

Combined infrared multiphoton dissociation and electron capture dissociation with a hollow electron beam in Fourier transform ion cyclotron resonance mass spectrometry.

An electron injection system based on an indirectly heated ring-shaped dispenser cathode has been developed and installed in a 7 Tesla Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. This new hardware design allows high-rate electron capture dissociation (ECD) to be carried out by a hollow electron beam coaxial with the ion cyclotron resonance (ICR) trap. Infrared multiphoton dissociation (IRMPD) can also be performed with an on-axis IR-laser beam passing through a hole at the centre of the dispenser cathode.

A novel mass spectrometric approach to the analysis of hormonal peptides in extracts of mouse pancreatic islets.

Liquid chromatography mass spectrometry (LC-MS) is a valuable tool in the analysis of proteins and peptides. The combination of LC-MS with different fragmentation methods provides sequence information on components in complex mixtures. In this work, on-line packed capillary LC electrospray ionization Fourier transform ion cyclotron resonance MS was combined with two complementary fragmentation techniques, i.

Rapid analysis of tryptically digested cerebrospinal fluid using capillary electrophoresis-electrospray ionization-Fourier transform ion cyclotron resonance-mass spectrometry.

Mass spectrometry has in recent years been established as the method of choice for protein identification and characterization in proteomics. Capillary electrophoresis (CE) is a fast and efficient method for the separation of peptides and proteins. The on-line combination of CE with Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS) has been shown to be a powerful tool in the analysis of complex mixtures of proteins.

Protein identification in cerebrospinal fluid using packed capillary liquid chromatography Fourier transform ion cyclotron resonance mass spectrometry.

The identification and characterization of proteins in complex biological samples such as body fluids, require powerful and reliable tools. Mass spectrometry is today one of the most important methods in such research. This paper reports on the results from the first experiment where a tryptic digest of cerebrospinal fluid was analyzed applying reversed phase liquid chromatography coupled on-line to a 9.

Prediction of chromatographic retention and protein identification in liquid chromatography/mass spectrometry.

Liquid chromatography coupled on- or off-line with mass spectrometry is rapidly advancing as a tool in proteomics capable of dealing with the inherent complexity in biology and complementing conventional approaches based on two-dimensional gel electrophoresis. Proteins can be identified by proteolytic digestion and peptide mass fingerprinting or by searching databases using short-sequence tags generated by tandem mass spectrometry. This paper shows that information on the chromatographic behavior of peptides can assist protein identification by peptide mass fingerprinting in liquid chromatography/mass spectrometry.

Ionization energies of multiply protonated polypeptides obtained by tandem ionization in Fourier transform mass spectrometers.

Ionization energies (IE) of [M + zH](z+) (z+) electrospray-produced polypeptides were determined by electron ionization in a Penning cell of 4.7 and 9.4 T Fourier transform mass spectrometers.

Peptide mapping of proteins in human body fluids using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry.

Human body fluids have been rediscovered in the post-genomic era as great sources of biological markers and perhaps particularly as sources of potential protein biomarkers of disease. Analytical tools that allow rapid screening, low sample consumption, and accurate protein identification are of great importance in studies of complex biological samples and clinical diagnosis. Mass spectrometry is today one of the most important analytical tools with applications in a wide variety of fields.

Liquid chromatography and electron-capture dissociation in Fourier transform ion cyclotron resonance mass spectrometry.

Liquid separation methods in combination with electrospray mass spectrometry as well as the recently introduced fragmentation method electron capture dissociation (ECD) have become powerful tools in proteomics research. This paper presents the results of the first successful attempts to combine liquid chromatography (LC) and Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) with ECD in the analysis of a mixture of standard peptides and of a bovine serum albumin tryptic digest. A novel electron injection system provided conditions for ECD sufficient to yield extensive sequence information for the most abundant peptides in the mixtures on the time-scale of the chromatographic separation.