Comparison of the mannan structure from the cell-wall mutant Candida sp. M-7002 and its wild type. I. Characterization of the proteo-mannan from the mutant and the wild-type cells.
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 Cetavlon and copper reagent. Both mannans contain D-mannose, D-glucose and phosphate. The mutant mannan has a relatively high content of protein (18% in weight bases) whereas the wild-type mannan has a low protein content (5.1%) with a high amount of carbohydrate (greater than 90%). Structural analyses by enzymatic and chemical methods showed that both mannans had a mannosidic (alpha 1--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 mannose units and disaccharide units whose linkages were predominantly alpha 1--2, while the wild-type mannan had two additional side chains of disaccharides. These additional side chains had alpha 1--3 linkages which were scarcely found in the mutant mannan. beta-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 (alpha 1--6)-linked mannan back bone.
D002175:Candida / Q000032:analysis* / Q000648:ultrastructure; D002462:Cell Membrane / Q000648:ultrastructure; D006023:Glycoproteins / Q000032:analysis*; D008351:Mannans / Q000032:analysis*; D008562:Membrane Glycoproteins; D008855:Microscopy, Electron, Scanning; D009154:Mutation; D011134:Polysaccharides / Q000032:analysis*; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D013045:Species Specificity; D000520:alpha-Glucosidases
D006023:Glycoproteins; D008351:Mannans; D008562:Membrane Glycoproteins; D011134:Polysaccharides; C025363:mannoproteins; D000520:alpha-Glucosidases