Comparison of the Mannan Structure from the Cell-Wall Mutant <em>Candida</em> sp. M-7002 and Its Wild Type.

The cell-wall mutant of a hydrocarbon-assimilating yeast, Candida sp. M-7002 and its wild type have shown a significant difference in mannose content. Each mannan was isolated from the mutant and the wild-type cells by fractionation with Cetavion and copper reagent. Both mannans contain D-mannose, D-glucose and phosphate. The mutant mannan has a relatively high content of protein (1870 in weight bases) whereas the wild-type mannan has a low protein content (5.1%) with a high amount of carbohydrate (&gt;90%). Structural analyses by enzymatic and chemical methods showed that both mannans had an mannosidic (α1 -6)-linked back bone substituted at O-2 by side chains of varying length. The side chains of the mutant mannan were shown to consist of single niannose units and disaccharide units whose linkages were predominantly α1 -2. while the wild-type mannan had two additional side chains of disaccharides. These additional side chains had α1-3 linkages which were scarcely found in the mutant mannan. β-Elimination reaction demonstrated that the mannans also contain mannosyl oligosaccharides linked to protein through O-glycosidic linkage. The chemical properties of the mannan of the Candida mutant indicates that the mutation might occur not only in the side chain structure but also in the (α1 -6)-linked mannan back bone. [ABSTRACT FROM AUTHOR]