Cross-species identification of novel Candida albicans immunogenic proteins by combination of two-dimensional polyacrylamide gel electrophoresis and mass spectrometry.
We have previously reported the usefulness of two-dimensional gel electrophoresis followed by Western blotting with sera from patients with systemic candidiasis in the detection of the major Candida albicans antigens (Pitarch et al., Electrophoresis 1999, 20, 1001-1010). The identification of these antigens would be useful for the characterization of good markers for the disease, and for the development of efficient diagnostic strategies. In this work we have used nanoelectrospray tandem mass spectrometry to obtain amino acid sequence information from the immunogenic proteins previously detected. We report here the cross-species identification of these antigens by matching of tandem mass spectrometry data to Saccharomyces cerevisiae proteins. Using this approach, we unambiguously identified the four C. albicans immunogenic proteins analyzed, namely aconitase, pyruvate kinase, phosphoglycerate mutase and methionine synthase. Furthermore, we report for the first time that aconitase, methionine synthase and phosphoglycerate mutase have antigenic properties in C. albicans.
Pardo
M
M
Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Spain.
Ward
M
M
Pitarch
A
A
Sánchez
M
M
Nombela
C
C
Blackstock
W
W
Gil
C
C
D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase / Q000032:analysis / Q000276:immunology; D000154:Aconitate Hydratase / Q000032:analysis / Q000276:immunology; D000595:Amino Acid Sequence; D000946:Antigens, Fungal / Q000032:analysis / Q000276:immunology*; D002176:Candida albicans / Q000737:chemistry / Q000276:immunology*; D016208:Databases, Factual; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D005656:Fungal Proteins / Q000032:analysis / Q000276:immunology*; D008969:Molecular Sequence Data; D010736:Phosphoglycerate Mutase / Q000032:analysis / Q000276:immunology; D011770:Pyruvate Kinase / Q000032:analysis / Q000276:immunology; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000276:immunology*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D000946:Antigens, Fungal; D005656:Fungal Proteins; D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase; D011770:Pyruvate Kinase; D000154:Aconitate Hydratase; D010736:Phosphoglycerate Mutase