JBC, Vol. 252, Issue 8, 2584-2591, Apr, 1977

Chemical structure of the galactomannan from the cell wall of Aspergillus niger

P. C. Bardalaye and J. H. Nordin

The galactomannan of surface grown Aspergillus niger has been isolated by alkaline extraction of hyphal walls and characterized structurally. Its elution profile, from a column of Bio-Gel P-150, reveals a broad range of molecular sizes grouped into two fractions. Gas chromatographic and colorimetric analyses indicate that each fraction is composed of approximately equimolar quantities of galactose and mannose plus 12 to 14% glucose. Both have similar low optical rotations and contain acid labile galactose. Methylation, Smith degradation, acetolysis, reactivity with concanavalin A and beta-D-galactofuranosidase, plus digestionof galactose with D-galactose oxidase, were techniques employed to determine the polysaccharide's covalent structure. Results of these studies indicate that it is composed of a series of chains, 5 to 9 hexose units in length, connected by alpha1 leads to 6 bonds between mannopyranosyl moieties. The external portion of each chain consists of a galactose tri- or tetrasaccharide of the general structure Galf beta1 leads to 4 Galp(1-2) 1 leads to 4 Galp1 leads to. This segment is connected via a (1 leads to 2) linkage to the internal portion which is a di- to pentasaccharide of mannopyranosyl units joined in alpha1 leads to 2 glycoside linkage. Combination mild acid hydrolysis and methylation experiments indicate galactofuranosyl terminal units are attached only to galactose. The organization of glucose into the overall structure of the polymer has not been determined. Structural relationships of this polysaccharide to both fungal and yeast galactomannans are discussed.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				R. A. Damveld, A. Franken, M. Arentshorst, P. J. Punt, F. M. Klis, C. A. M. J. J. van den Hondel, and A. F. J. Ram A Novel Screening Method for Cell Wall Mutants in Aspergillus niger Identifies UDP-Galactopyranose Mutase as an Important Protein in Fungal Cell Wall Biosynthesis Genetics, February 1, 2008; 178(2): 873 - 881. [Abstract] [Full Text] [PDF]

				R. M. van der Kaaij, X.-L. Yuan, A. Franken, A. F. J. Ram, P. J. Punt, M. J. E. C. van der Maarel, and L. Dijkhuizen Two Novel, Putatively Cell Wall-Associated and Glycosylphosphatidylinositol-Anchored {alpha}-Glucanotransferase Enzymes of Aspergillus niger Eukaryot. Cell, July 1, 2007; 6(7): 1178 - 1188. [Abstract] [Full Text] [PDF]

				C. Costachel, B. Coddeville, J.-P. Latge, and T. Fontaine Glycosylphosphatidylinositol-anchored Fungal Polysaccharide in Aspergillus fumigatus J. Biol. Chem., December 2, 2005; 280(48): 39835 - 39842. [Abstract] [Full Text] [PDF]

				B. A. Tuekam, Y.-I. Park, C. J. Unkefer, and J. E. Gander Relationship of Exo-{beta}-D-Galactofuranosidase Kinetic Parameters to the Number of Phosphodiesters in Penicillium fellutanum Peptidophosphogalactomannan: Enzyme Purification and Kinetics of Glycopeptide and Galactofuran Chain Hydrolysis Appl. Envir. Microbiol., October 1, 2001; 67(10): 4648 - 4656. [Abstract] [Full Text]

				J.-P. Latge Aspergillus fumigatus and Aspergillosis Clin. Microbiol. Rev., April 1, 1999; 12(2): 310 - 350. [Abstract] [Full Text] [PDF]

				J. Jungmann, J. C. Rayner, and S. Munro The Saccharomyces cerevisiae Protein Mnn10p/Bed1p Is a Subunit of a Golgi Mannosyltransferase Complex J. Biol. Chem., March 5, 1999; 274(10): 6579 - 6585. [Abstract] [Full Text] [PDF]