The application of mass spectrometry (MS) to the study of progressively larger and more complex macromolecular assemblies is proving increasingly useful for structural biologists. The scope of this approach has recently been widened through the application of a tandem MS procedure. This two-step technique involves the selection of specific assemblies in the gas phase and inducing their dissocia...

An overview of chromatography-mass spectrometry coupling is presented here, focussing mainly on possibilities offered by this detection technique. GC-MS and HPLC-MS are the two most often used variants, which have quite different characteristics. Various mass-spectrometric possibilities are briefly discussed: ionization techniques, determination of elemental formulas, structural information and...

Despite recent technological advances, the analysis of biological samples for metabolite identification purposes often requires prior knowledge of the metabolite masses to successfully acquire high quality mass spectral data in the presence of intense background and interfering matrix signals. This, in turn, necessitates prior knowledge of the metabolite structure, which in most cases can be pr...

A variety of methods have been described in the literature for assigning statistical significance to peptides identified via tandem mass spectrometry. Here, we explain how two types of scores, the q-value and the posterior error probability, are related and complementary to one another.

The importance of Brazil as a producer and exporter of food and feed will continuously increase. Despite the recent economic and political problems in Brazil, the scientific field is expanding. Cutting-edge technology has only recently become available in the country, and we can now also join efforts with the global community to tackle global challenges. Using metabolomics based on mass spectro...

reflects increased erythropoietic activity in this period. In conclusion, we found that sTfR concentrations do exhibit gestational age-related changes during pregnancy: the value of sTfR increased with gestational age during pregnancy and returned to nonpregnancy values 12 weeks after delivery. Increases in sTfR concentrations during pregnancy seem to be influenced more by increased erythropoie...

Although tandem mass spectrometry has revolutionized the identification and structural characterization of peptides and proteins, future advances in comprehensive proteome analysis will depend on the development of improved methods for ion activation that yield greater sequence information, and with selective control over the fragmentation chemistry. This report presents initial findings that d...

Aqueous mixtures of formaldehyde and glutathione react to form a variety of cyclized adducts in addition to S-hydroxymethylglutathione. The adducts are in labile equilibrium with each other and are not readily separated. The structures of two of the other major adducts were determined by concerted application of 13C-1H two-dimensional chemical-shift correlation, fast-atom-bombardment mass spect...

in previous studies, mebudipine, a dihydropyridine calcium channel blocker, showed a considerable potential to be used in cardiovascular diseases. the aim of the current study was to develop a valid method using reversed-phase high performance liquid chromatography coupled with electrospray ionization mass spectrometry to assay mebudipine in the human plasma. separation was achieved on a zorbax...