Candida albicans mannan

The cell wall of the yeast Candida albicans contains glucan and mannan extractable with hot, aqueous alkali. Bishop and associates ... 

Fig. 12.—Separation of Methanolysis Products from Methylated Mannan of Candida albicans. (Key (A) methyl 2,3,4,6-tetra-O-methyl-a-D-mannopyranoside (B) unknown (C) methyl 3,4,6-tri-O-raethyl-a-D-mannopyranoside (D) methyl 2,3,6-tri-O-methyl-a-D-mannopyranoside (E) methyl 3,4-di-0-methyI-a-D-mannopyranoside.)...

The mannans isolated from Candida albicans strains, NIH A-207 (serotype A), NIH B-792 (serotype B), and J-1012 (serotype C), were fractionated on a column of DEAE-Sephadex into five subfractions containing different amounts of phosphate. 

Netea MG, Gow NA, Munro CA et al. Immune sensing of Candida albicans requires cooperative recognition of mannans and glucans by lectin and Toll-like receptors. J Clin Invest 2006 116 1642-1650. 

The D-mannan (22) isolated from Lampteromyces japonicus resembles that from 5. cerevisiae except for the absence of (1 3)-linkages. A closer structural resemblance exists with the D-mannans of Saccharomyces rouxiU Trichosporon aculeatum, and Candida albicans. 

The association of chitin, D-glucan, and D-mannan in the cell walls of Candida albicans and the spatial distribution of these polysaccharides have been found to vary appreciably between two dimorphs and with the age of the culture. ... 

Although a variety of serologic tests have been proposed for the detection of Candida protein antigens, serum antibodies to Candida, and antibodies to cell wall components such as mannan, no test has demonstrated reliable accuracy in the clinical setting for the diagnosis of disseminated infection with Candida. Only 25% to 45% of neutropenic patients with disseminated candidiasis at autopsy had a positive blood culture with C. albicans prior to death. The interpretation of positive surveillance cultures of the skin, mouth, sputum, feces, or urine is hampered by their occurrence as commensal pathogens and in distinguishing colonization from invasive disease. 

In 1965, an important modification of the chemical structure of bakers yeast mannan was made by Ballou and his co-workers. They pointed out that the longest branching moieties of this mannan correspond to a tetraose, 0-orD-mannopyranosyl (1 - 3) 0-(x-D-mannopyranosyl (1- 2) O-oc-o-mannopyranosyl (l->2) mannose (23). In 1967, the Canadian workers and Hasenclever published the modified findings of structural analysis of the mannan of several Candida strains including those of C. albicans serotype A, C. albicans serotype B, C. tropicalis, C. stellatoidea, and C. parapsilosis, affording evidence that all mannans contain small amounts of al->3 linked D-mannopyranosyl residues in addition to the large amounts of al->2 and ocl->6 linkages (24). ... 

P-Man-T activities involved in modifying cell wall mannan of the fungal genus Candida [69], which includes the human pathogen C. albicans. In Saccharomyces cerevisiae, the genes for the Man-T that add additional a-linked Man to protein-bound GPI anchors in the Golgi may yet be found in the Mnnlp or Ktrlp families. 

---