NMR comparison of hyphal and yeast Candida albicans serotype B mannans

A change from a globular to a filamentous hyphal form is an important feature in the pathogenicity of yeasts. Such a dimorphism while infecting a host organism is thought to be also accompanied in the case of Candida albicans spp. by a structural rearrangement of surface mannan antigen. The presented work brings new insights into the molecular structural changes of mannan C. albicans serotype B based on NMR experimental data. 1 H and 13 C signal identification of the anomeric region and the assignment of their linkage type is presented here. 2D deconvolution of the HSQC spectra facilitated accurate integration of all anomeric cross-peaks. Analysis of the differences in the integrals led to the proposal that C. albicans serotype B hyphal mannan side chains have the shortened structural moieties: Manα1-2Manα1- and Manα1-3 [Manα1-6] Manα1-2Manα1-. These represent the dominant structures important for construction of a saccharide-based prospective anti-candida vaccine.