The biosynthesis of D-Galacturonate in plants. functional cloning and characterization of a membrane-anchored UDP-D-Glucuronate 4-epimerase from Arabidopsis

Plant Physiology
Michael MølhøjWolf-Dieter Reiter

Abstract

Pectic cell wall polysaccharides owe their high negative charge to the presence of D-galacturonate, a monosaccharide that appears to be present only in plants and some prokaryotes. UDP-D-galacturonate, the activated form of this sugar, is known to be formed by the 4-epimerization of UDP-D-glucuronate; however, no coding regions for the epimerase catalyzing this reaction have previously been described in plants. To better understand the mechanisms by which precursors for pectin synthesis are produced, we used a bioinformatics approach to identify and functionally express a UDP-D-glucuronate 4-epimerase (GAE1) from Arabidopsis. GAE1 is predicted to be a type II membrane protein that belongs to the family of short-chain dehydrogenases/reductases. The recombinant enzyme expressed in Pichia pastoris established a 1.3:1 equilibrium between UDP-D-galacturonate and UDP-D-glucuronate but did not epimerize UDP-D-Glc or UDP-D-Xyl. Enzyme assays on cell extracts localized total UDP-D-glucuronate 4-epimerase and recombinant GAE1 activity exclusively to the microsomal fractions of Arabidopsis and Pichia, respectively. GAE1 had a pH optimum of 7.6 and an apparent Km of 0.19 mm. The recombinant enzyme was strongly inhibited by UDP-D-Xyl but no...Continue Reading

References

Aug 15, 1991·Analytical Biochemistry·T M Filisetti-Cozzi, N C Carpita
Apr 22, 1969·Biochimica Et Biophysica Acta·H Ankel, R G Tischer
May 9, 1995·Biochemistry·H JörnvallD Ghosh
Mar 9, 1999·The Plant Journal : for Cell and Molecular Biology·S J Clough, A F Bent
Nov 12, 2002·Journal of Bacteriology·David H KeatingSharon R Long
Sep 1, 1958·Biochimica Et Biophysica Acta·E E SMITHR AUSTRIAN
Dec 23, 2003·Infection and Immunity·Miguel ReguéJuan M Tomás

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Citations

Jul 1, 2009·Journal of Biochemistry·Xiaogang GuMaor Bar-Peled
May 7, 2009·Nucleic Acids Research·Leonardo AlvesThomas Merkle
Nov 21, 2009·Plant Physiology·Bryan W PenningNicholas C Carpita
Mar 5, 2013·Annual Review of Plant Biology·Melani A AtmodjoDebra Mohnen
Oct 14, 2009·Phytochemistry·Shou TakashimaYasuhiro Hashimoto
Jan 26, 2013·Plant Biotechnology Journal·Shahram EmamiAlan B Rose
Feb 24, 2015·The Plant Journal : for Cell and Molecular Biology·Sang-Jin KimFederica Brandizzi
Apr 4, 2006·Analytical Biochemistry·Takao OhashiSumihiro Hase
Mar 20, 2015·Plant Molecular Biology·Sylvain LegayJean-Francois Hausman
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Jun 5, 2018·International Journal of Molecular Sciences·Xing DingXingguo Zhang
Apr 29, 2006·The Journal of Biological Chemistry·Christine BarberGeorg J Seifert
Nov 10, 2018·Evidence-based Complementary and Alternative Medicine : ECAM·Peng WuWeifeng Sun
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