HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Smith, W. L. Articles by Ballou, C. E. Search for Related Content PubMed PubMed Citation Articles by Smith, W. L. Articles by Ballou, C. E. Social Bookmarking                      What's this?

JBC, Vol. 250, Issue 9, 3426-3435, May, 1975

Biosynthesis of yeast mannan. Isolation of Kluyveromyces lactis mannan mutants and a study of the incorporation of N-acetyl-D-glucosamine into the polysaccharide side chains

W. L. Smith, T. Nakajima and C. E. Ballou

One side chain in the cell wall mannan of the yeast Kluyveromyces lactis has the structure (see article). (Raschke, W. C., and Ballou, C. E. (1972) Biochemistry 11, 3807). This (Man)4GNAc unit (the N-acetyl-D-glucosamine derivative of mannotetroase) and the (Man)4 side chain, aMan(1 yields 3)aMan(1 yields 2)aMan(1 yields 2)Man, are the principle immunochemical determinants on the cell surface. Two classes of mutants were obtained which lack the N-acetyl-D-glucosamine-containing determinant. The mannan of one class, designated mmnl, lacks both the (Man)4GNAc and (Man)4 side chains. Apparently, it has a defective alpha-1 yields 3-mannosyltransferase and the (Man)4 unit must be formed to serve as the acceptor before the alpha-1 yields 2-N-acetyl-glucosamine transferase can act. The other mutant class, mnn2, lacks only the (Man)4GNAc determinant and must be defective in adding N-acetylglucosamine to the mannotetrasose side chains. Two members of this class were obtained, one which still showed a wild type N-acetylglucosamine transferase activity in cell-free extracts and the other lacking it. They are allelic or tightly linked, and were designated mnn2-1 mnn2-2. Protoplast particles from the wild type cells catalyzed a Mn2+-dependent transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to the mannotetraose side chain of endogenous acceptors. Exogenous mannotetraose also served as an acceptor in a Mn2+-dependent reaction and yielded (Man)4GNAc. Related oligosaccharides with terminal alpha (1 yields 3)mannosyl units were also good acceptors. The product from the reaction with alphaMan(1 yields 3)Man had the N-acetylglucosamine attached to the mannose unit at the reducing end, which supports the conclusion that the cell-free glycosyltransferase activity is identical with that involved in mannan synthesis. The reaction was inhibited by uridine diphosphate. Protoplast particles from the mmnl mutants showed wild type N-acetylglucosamine transferase activity with exogenous acceptor, but they had no endogenous activity because the endogenous mannan lacked acceptor side chains. Particles from the mnn2-1 mutant failed to catalyze N-acetylglucosamine transfer. In contrast, particles from the mnn2-2 mutant were indistinguishable from wild type cells in their transferase activity. Some event accompanying cell breakage and assay of the mnn2-2 mutant allowed expression of a latent alpha-1 yields 2-N-acetylglucosamine transferase with kinetic properties similar to those of the wild type enzyme.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				J. Hoflich, P. Berninsone, C. Gobel, M. J. Gravato-Nobre, B. J. Libby, C. Darby, S. M. Politz, J. Hodgkin, C. B. Hirschberg, and R. Baumeister Loss of srf-3-encoded Nucleotide Sugar Transporter Activity in Caenorhabditis elegans Alters Surface Antigenicity and Prevents Bacterial Adherence J. Biol. Chem., July 16, 2004; 279(29): 30440 - 30448. [Abstract] [Full Text] [PDF]

				T. Yoko-o, C. A.R. Wiggins, J. Stolz, S. Y. Peak-Chew, and S. Munro An N-acetylglucosaminyltransferase of the Golgi apparatus of the yeast Saccharomyces cerevisiae that can modify N-linked glycans Glycobiology, August 1, 2003; 13(8): 581 - 589. [Abstract] [Full Text] [PDF]

				E. Guillen, C. Abeijon, and C. B. Hirschberg The Genes for the Golgi Apparatus N-Acetylglucosaminyltransferase and the UDP-N-acetylglucosamine Transporter Are Contiguous in Kluyveromyces lactis J. Biol. Chem., March 5, 1999; 274(10): 6641 - 6646. [Abstract] [Full Text] [PDF]

				C. Abeijon, E. C. Mandon, P. W. Robbins, and C. B. Hirschberg A Mutant Yeast Deficient in Golgi Transport of Uridine Diphosphate N-Acetylglucosamine J. Biol. Chem., April 12, 1996; 271(15): 8851 - 8854. [Abstract] [Full Text] [PDF]