Biochemical characterization of a trypanosomatid isolated from the plant Amaranthus retroflexus

A protozoan flagelate has recently been isolated from Amaranthus retroflexus. This plant grows near economically important crops in southeastern Spain, which are known to be parasitized by Phytomonas spp. The present study focuses on the characterization of the energy metabolism of this new isolate. These flagellates utilize glucose efficiently as their primary energy source, although they are unable to completely degrade it. They excrete ethanol, acetate, glycine, and succinate in lower amount, as well as ammonium. The presence of glycosomes was indicated by the early enzymes of the glycolytic pathway, one enzyme of the glycerol pathway (glycerol kinase), and malate dehydrogenase. No evidence of a fully functional citric-acid cycle was found. In the absence of catalase activity, these flagellates showed significant superoxide dismutase activity located in the glycosomal and cytosolic fractions. These trypanosomes, despite being morphologically and metabolically similar to other Phytomonas isolated from the same area, showed significant differences, suggesting that they are phylogenetically different species.

Characterization of phosphoinositol oligosaccharides from parasitic protozoa by fast atom bombardment and collisional activation mass spectrometry

Fast atom bombardment mass spectrometry (FAB MS) enables the rapid, accurate and sensitive determination of the molecular masses of glycosylphosphatidylinositol(GPI)-derived oligosaccharides, from which the composition in terms of monosaccharide residues and non-carbohydrate substituents can be determined. Interpretation of fragment ions in collisional activation mass spectra further enables the determination of residue sequence, the positions of branch points, and the location of non-carbohydrate substituents. We have applied these techniques to the characterization of phosphoinositol oligosaccharides from Leptomonas samueli, Endotrypanum schaudinni and Leishmania adleri. The mass spectral data permit the postulation of candidate structures for the oligosaccharides, which provide a set of constraints that can assist the interpretation of results from other techniques such as NMR

Structures of four oligosaccharides derived from the glycoinositolphospholipid of Leishmania adleri

Glycoinositolphospholipids (GIPLs) were extracted from the trypanosomatid Leishmania adleri by hot phenol extraction and the carbohydrate moieties isolated after base cleavage. Purification of the crude oligosaccharides by high performance anion exchange (HPAE) chromatography yielded four fractions whose structures were determined by a combination of methylation analysis, fast atom bombardment (FAB) mass spectrometry and two-dimensional nuclear magnetic resonance (NMR) spectroscopy

The use of NMR spectroscopy in the structure determination of a Leptomonas samueli glycosylphosphosphingolipid-derived oligosaccharide

Nuclear magnetic resonance (NMR) spectroscopy provides an extremely powerful technique to determine the structure of oligosaccharides, particularly when used in conjuction with other physical techniques such as methylation analysis and fast atom bombardment mass spectroscopy (FAB-MS). This brief review describes the application of NMR to the determination of the structure of an oligosaccharide isolated from the glycophosphosphingolipid (GPS) from the monogenetic trypanosomatid Leptomonas samueli. Where ambiguities arise in the NMR interpretation, the use of other data will be discussed