Structural identification of an epitope of antigenic factor 5 in mannans of Candida albicans NIH B-792 (serotype B) and J-1012 (serotype A) as beta-1,2-linked oligomannosyl residues.
In previous articles, we reported the presence of phosphate-bound beta-1,2-linked oligomannosyl residues in the mannans of strains of Candida albicans serotypes A and B and Candida stellatoidea. To identify the antigenic factor corresponding to this type of oligomannosyl residue, a relationship between chemical structure and antigenic specificity in the mannans of C. albicans NIH B-792 (serotype B, B-strain) and C. albicans J-1012 (serotype A, J-strain) was investigated by using a combination of two-dimensional 1H nuclear magnetic resonance spectroscopy of H-1, H-2, and H-5 regions in the mannans and an enzyme-linked immunosorbent assay that employed concanavalin A-coated microtiter plates. It was shown in the present 1H nuclear magnetic resonance study that an examination of chemical shifts not only in the H-1 region but also in the H-5 region was useful for the quantitative determination of the phosphate-bound beta-1,2-linked oligomannosyl residues. In the enzyme-linked immunosorbent assay using concanavalin A-coated plates, it was revealed that, of factor sera 1, 4, and 5, only factor serum 5 showed a reactivity proportional to the densities of the beta-1,2-linked oligomannosyl residues of the mannan subfractions of different phosphate contents that had been prepared from the bulk B-strain mannan by DEAE-Sephadex chromatography. The above results indicate that the phosphate-bound beta-1,2-linked oligomannosyl residues, Manp beta 1----(2Manp beta 1----)n2Man (n = 0-5), correspond to antigenic factor 5.
Shibata
N
N
Second Department of Hygienic Chemistry, Tohoku College of Pharmacy, Sendai, Japan.
Arai
M
M
Haga
E
E
Kikuchi
T
T
Najima
M
M
Satoh
T
T
Kobayashi
H
H
Suzuki
S
S
D000946:Antigens, Fungal / Q000276:immunology*; D002176:Candida albicans / Q000276:immunology*; D002240:Carbohydrate Sequence; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000032:analysis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008351:Mannans / Q000737:chemistry / Q000276:immunology*; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry* / Q000276:immunology
D000946:Antigens, Fungal; D000939:Epitopes; D008351:Mannans; D009844:Oligosaccharides; C028569:oligomannoside