Structure and antigenicity of the mannans of Candida famata and Candida saitoana: comparative study with the mannan of Candida guilliermondii.
The chemical structure of the mannans of antigenic factor 9-expressing yeast, Candida famata and Candida saitoana, was analyzed by acetolysis and NMR. The structural study of the oligosaccharides and mannans using one- and two-dimensional NMR indicated that the mannan of C. saitoana contains a third type of beta-1,2-linked mannose unit. On the other hand, the mannan of C. famata does not contain any beta-1,2-linked mannose units. The mannan of C. saitoana gave two groups of beta-1,2 linkage-containing oligosaccharides by acetolysis. One contains one beta-1,2-linked mannose unit and the other contains two consecutive beta-1,2-linked mannose units at the nonreducing terminal. The inhibition of the reactivity of factor 9 serum on an enzyme-linked immunosorbent assay (ELISA) with these oligosaccharides indicated that the inhibition activity of the former oligosaccharide is 1/20 of that of the latter ones. The ELISA of the mannans of Candida guilliermondii, C. saitoana, and Saccharomyces kluyveri, all of which contain the third type of beta-1,2-linked mannose unit, indicated that Man(beta)1--> 2Man(beta)1-->2Man(alpha)1-->3Man(alpha)1-->works as the antigenic factor 9 but Man(beta)1-->2Man(alpha)1-->3Man(alpha)1--> weakly behaves as both antigenic factors 6 and 9. The epitope structures of the side chain oligosaccharides agreed well with that proposed from the 2D-HOHAHA spectra of the mannans. This result demonstrates the usefulness of the H-1 - H-2-correlated cross-peak pattern, which was reported in a preceding paper (Shibata, N., Akagi, R., Hosoya, T., Kawahara, K., Suzuki, A., Ikuta, K., Kobayashi, H., Hisamichi, K., Okawa, Y., and Suzuki, S. (1996) J. Biol. Chem. 271, 9259-9266) for the determination of the epitope structure of Candida mannans without any chemical fragmentation.
Shibata
N
N
Second Department of Hygienic Chemistry, Tohoku College of Pharmacy, Miyagi, Japan.
Onozawa
M
M
Tadano
N
N
Hinosawa
Y
Y
Suzuki
A
A
Ikuta
K
K
Kobayashi
H
H
Suzuki
S
S
Okawa
Y
Y
D019342:Acetic Acid; D000946:Antigens, Fungal / Q000737:chemistry*; D002175:Candida / Q000737:chemistry* / Q000276:immunology*; D002240:Carbohydrate Sequence; D006241:Haptens / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008351:Mannans / Q000737:chemistry* / Q000276:immunology*; D008969:Molecular Sequence Data
D000946:Antigens, Fungal; D006241:Haptens; D008351:Mannans; D019342:Acetic Acid