Galactomannans of Trichosporon fermentans and other yeasts; proton magnetic resonance and chemical studies

Abstract

A survey of the alkali soluble polysaccharides of yeast cells shows that galactomannans are formed by certain species of the genera Trichosporon, Schizosaccharomyces, and Nadsonia. Different species of Trichosporon form galactomannans, pentosylmannans, and a mannan. The galactomannans are distinguishable from those of Schizosaccharomyces by the H-1 region of their proton magnetic resonance spectra (recorded at 70° in D₂O using an HA-100 Varian spectrometer), but the spectra of Trichosporon hellenicum and Nadsonia fulvescens galactomannans are virtually indistinguishable.The proton magnetic resonance spectrum of the Trichosporon fermentans galactomannan contains fewer signals than those of other Trichosporon galactomannans. The polymer consists predominantly of a main-chain containing a high proportion of (1 → 6)-mannopyranosyl units substituted in their 2-positions by O-α-D-galactopyranosyl-(1 → 2)-O-α-D-mannopyranosyl side-chains (1).