Print Email Facebook Twitter Localization of synthesis of β1,6-glucan in Saccharomyces cerevisiae Title Localization of synthesis of β1,6-glucan in Saccharomyces cerevisiae Author Montijn, R.C. Vink, E. Müller, W.H. Verkleij, A.J. van den Ende, H. Henrissat, B. Klis, F.M. Centraal Instituut voor Voedingsonderzoek TNO Publication year 1999 Abstract β1,6-Glucan is a key component of the yeast cell wall, interconnecting cell wall proteins, β1,3-glucan, and chitin. It has been postulated that the synthesis of β1,6-glucan begins in the endoplasmic reticulum with the formation of protein-bound primer structures and that these primer structures are extended in the Golgi complex by two putative glucosyltransferases that are functionally redundant, Kre6 and Skn1. This is followed by maturation steps at the cell surface and by coupling to other cell wall macromolecules. We have reinvestigated the role of Kre6 and Skn1 in the biogenesis of β1,6- glucan. Using hydrophobic cluster analysis, we found that Kre6 and Skn1 show significant similarities to family 16 glycoside hydrolases but not to nucleotide diphospho-sugar glycosyltransferases, indicating that they are glucosyl hydrolases or transglucosylases instead of genuine glucosyltransferases. Next, using immunogold labeling, we tried to visualize intracellular β1,6-glucan in cryofixed sec1-1 cells which had accumulated secretory vesicles at the restrictive temperature. No intracellular labeling was observed, but the cell surface was heavily labeled. Consistent with this, we could detect substantial amounts of β1,6-glucan in isolated plasma membrane-derived microsomes but not in post-Golgi secretory vesicles. Taken together, our data indicate that the synthesis of β1,6-glucan takes place largely at the cell surface. An alternative function for Kre6 and Skn1 is discussed. Subject NutritionChitinGlucanGlucosyltransferaseGlycosidaseBeta 1,6 glucanBeta glucanBeta-1,6-glucanFungal proteinKRE6 protein, S cerevisiaeMembrane proteinMultienzyme complexSaccharomyces cerevisiae proteinSKN1 protein, S cerevisiaeTransferaseTransglycosidase enzyme systemAmino acid sequenceCell surfaceCell wallEndoplasmic reticulumGolgi complexMembrane vesicleMicrosomeNonhumanNucleotide sequencePriority journalSaccharomyces cerevisiaeSynthesisBiosynthesisCell membraneMetabolismMolecular geneticsProtein conformationProtein secondary structureSaccharomyces cerevisiaeSaccharomyces cerevisiaeAmino Acid Sequencebeta-GlucansCell MembraneFungal ProteinsGlucansGlycoside HydrolasesMembrane ProteinsMolecular Sequence DataMultienzyme ComplexesProtein ConformationProtein Structure, SecondarySaccharomyces cerevisiaeSaccharomyces cerevisiae ProteinsTransferases To reference this document use: http://resolver.tudelft.nl/uuid:20be62d5-5d3e-49cc-b746-3934f57853c0 TNO identifier 235241 ISSN 0021-9193 Source Journal of Bacteriology, 181 (24), 7414-7420 Document type article Files To receive the publication files, please send an e-mail request to TNO Library.