Mannan structure analysis of the fragile Saccharomyces cerevisiae mutant VY1160

The fragile Saccharomyces cerevisiae mutant VY1160 has a cell-wall mannan with a lower molecular weight and a higher nitrogen content than the parental S288C strain. More mannobiose but less mannotriose and mannotetraose were found in O-glycosidically-bound oligosaccharides in the mutant. Acetolysis analysis of the alkali-stable mannan also showed a reduction of mannotetraose and an increase of the mannobiose fractions. Methylation analysis of total mannan, or side chains recovered after acetolysis, showed that in the mutant the amount of alpha(1-3)-linked mannose units prevailed over alpha(1-2)-linked residues.