Characterization of the sialate-7(9)-O-acetyltransferase from the microsomes of human colonic mucosa

Biological Chemistry
Yanqin ShenR Schauer

Abstract

Sialic acids present on human colonic mucins are highly O-acetylated, however, little is known about the underlying enzymatic activity required for O-acetylation in this tissue. Here we report on the substrate specificity, subcellular localization and characterization of the sialate-7(9)-O-acetyltransferase in normal human colonic mucosa. Using CMP-Neu5Ac, the most efficient acceptor substrate of all those tested, the enzymatic activity was found to be optimal at 37 degrees C, with a pH optimum of 7.0. Activity was also found to be dependent on protein, CMP-Neu5Ac (Km: 59.2 microM) and AcCoA (Km: 6.1 microM) concentrations, as well as membrane integrity. The enzyme's activity could be inhibited by CoA with a Ki of 11.9 microM. In addition, enzymatic activity was found to be localized in the Golgi-enriched membrane fraction. The nature of the O-acetylated products formed were verified with the aid of chromatographic and enzymatic techniques. The main product was 9-O-acetylated Neu5Ac, with a significant amount of oligo-O-acetylated Neu5Ac also being detected. The utilization of CMP-Neu5Ac as the acceptor substrate was confirmed by the isolation and characterization of the putative product, CMP-Neu5,9Ac2, using ion-exchange chrom...Continue Reading

References

Jan 1, 1978·Methods in Enzymology·R Schauer
Sep 12, 1979·Biochimica Et Biophysica Acta·J A Alhadeff, R T Holzinger
May 1, 1992·Biochemical Society Transactions·A P CorfieldR Schauer
Feb 1, 1992·Glycobiology·A Varki
Jul 1, 1990·Journal of Clinical Pathology·S Agawa, J R Jass
May 1, 1988·Journal of Cellular Biochemistry·J T Hutchins, C L Reading
Sep 1, 1987·FASEB Journal : Official Publication of the Federation of American Societies for Experimental Biology·E A MuchmoreA Varki
Nov 2, 1987·European Journal of Biochemistry·H J GrossR Brossmer
Nov 15, 1994·Analytical Biochemistry·T P Mawhinney, D L Chance
Jan 27, 1995·The Journal of Biological Chemistry·A K Datta, J C Paulson
Jan 1, 1994·Methods in Enzymology·G Reuter, R Schauer
Aug 23, 1996·Biochemical and Biophysical Research Communications·K OguraY Sanai
Apr 1, 1997·Proceedings of the National Academy of Sciences of the United States of America·A KanamoriY Hirabayashi
Mar 3, 1999·Glycoconjugate Journal·M IwersenR Schauer

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Citations

Dec 27, 2011·ACS Chemical Biology·Saddam M MuthanaJeffrey C Gildersleeve
Dec 18, 2002·The Journal of Experimental Medicine·Florence MalisanRoberto Testi
Sep 6, 2003·Biological Chemistry·Matthias IwersenRoland Schauer
Apr 23, 2004·Biological Chemistry·Yanqin ShenRoland Schauer
Jul 21, 2004·Proceedings of the National Academy of Sciences of the United States of America·Amanda L LewisAjit Varki
Dec 15, 2005·Zoology : Analysis of Complex Systems, ZACS·Roland Schauer
Jan 14, 2004·European Journal of Biochemistry·Yanqin ShenJoe Tiralongo
Jul 15, 2015·Nature Communications·Anna-Maria T BaumannMartina Mühlenhoff

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