INVESTIGADORES
COUTO Alicia Susana
artículos
Título:
Structural Analysis of the N-Glycans of the Major Cysteine Proteinase of Trypanosoma Cruzi. Identification of sulfated high-mannose type oligosaccharides.
Autor/es:
BARBOZA, MARIANA,; DUSCHAK ,VILMA G.,; FUKUYAMA,YUKO,; NONAMI, HIROSHI ,; ERRA-BALSELLS, ROSA,; CAZZULO, JUAN J.; COUTO, ALICIA S..
Revista:
EUROPEAN JOURNAL OF BIOCHEMISTRY
Editorial:
Blackwell Science Ltd.- Germany
Referencias:
Año: 2005 vol. 272 p. 3803 - 3815
ISSN:
0014-2956
Resumen:
Trypanosoma cruzi, the parasitic protozoan that causes Chagas disease,
contains a major cysteine proteinase, cruzipain. This lysosomal enzyme
bears an unusual C-terminal extension that contains a number of posttranslational
modifications, and most antibodies in natural and experimental
infections are directed against it. In this report we took advantage of
UV-MALDI-TOF mass spectrometry in conjunction with peptide N-glycosidase
F deglycosylation and high performance anion exchange chromatography
analysis to address the structure of the N-linked oligosaccharides
present in this domain. The UV-MALDI-TOF MS analysis in the negativeion
mode, using nor-harmane as matrix, allowed us to determine a new
striking feature in cruzipain: sulfated high-mannose type oligosaccharides.
Sulfated GlcNAc2Man3 to GlcNAc2Man9 species were identified. In
accordance, after chemical or enzymatic desulfation, the corresponding
signals disappeared. In addition, by UV-MALDI-TOF MS analysis (a) a
main population of high-mannose type oligosaccharides was shown in the
positive-ion mode, (b) lactosaminic glycans were also identified, among
them, structures corresponding to monosialylated species were detected,
and (c) as an interesting fact a fucosylated oligosaccharide was also detected.
The presence of the deoxy sugar was further confirmed by high performance
anion exchange chromatography. In conclusion, the total number
of oligosaccharides occurring in cruzipain was shown to be much higher
than previous estimates. This constitutes the first report on the presence of
sulfated glycoproteins in Trypanosomatids., the parasitic protozoan that causes Chagas disease,
contains a major cysteine proteinase, cruzipain. This lysosomal enzyme
bears an unusual C-terminal extension that contains a number of posttranslational
modifications, and most antibodies in natural and experimental
infections are directed against it. In this report we took advantage of
UV-MALDI-TOF mass spectrometry in conjunction with peptide N-glycosidase
F deglycosylation and high performance anion exchange chromatography
analysis to address the structure of the N-linked oligosaccharides
present in this domain. The UV-MALDI-TOF MS analysis in the negativeion
mode, using nor-harmane as matrix, allowed us to determine a new
striking feature in cruzipain: sulfated high-mannose type oligosaccharides.
Sulfated GlcNAc2Man3 to GlcNAc2Man9 species were identified. In
accordance, after chemical or enzymatic desulfation, the corresponding
signals disappeared. In addition, by UV-MALDI-TOF MS analysis (a) a
main population of high-mannose type oligosaccharides was shown in the
positive-ion mode, (b) lactosaminic glycans were also identified, among
them, structures corresponding to monosialylated species were detected,
and (c) as an interesting fact a fucosylated oligosaccharide was also detected.
The presence of the deoxy sugar was further confirmed by high performance
anion exchange chromatography. In conclusion, the total number
of oligosaccharides occurring in cruzipain was shown to be much higher
than previous estimates. This constitutes the first report on the presence of
sulfated glycoproteins in Trypanosomatids.2Man3 to GlcNAc2Man9 species were identified. In
accordance, after chemical or enzymatic desulfation, the corresponding
signals disappeared. In addition, by UV-MALDI-TOF MS analysis (a) a
main population of high-mannose type oligosaccharides was shown in the
positive-ion mode, (b) lactosaminic glycans were also identified, among
them, structures corresponding to monosialylated species were detected,
and (c) as an interesting fact a fucosylated oligosaccharide was also detected.
The presence of the deoxy sugar was further confirmed by high performance
anion exchange chromatography. In conclusion, the total number
of oligosaccharides occurring in cruzipain was shown to be much higher
than previous estimates. This constitutes the first report on the presence of
sulfated glycoproteins in Trypanosomatids.