Interacting polymer-modification enzymes in heparan sulfate biosynthesis

Tianji Zhang; Mingjia Yu; Honglian Li; Marco Maccarana; Wei Zhang; Deling Shi; Ying Kan; Xiao Zhang; Lianli Chi; Ulf Lindahl; Hongmei Li; Jin-Ping Li; Tianwei Tan

doi:10.1016/j.carbpol.2022.120191

Interacting polymer-modification enzymes in heparan sulfate biosynthesis

Carbohydr Polym. 2023 Jan 1:299:120191. doi: 10.1016/j.carbpol.2022.120191. Epub 2022 Oct 7.

Authors

Tianji Zhang¹, Mingjia Yu², Honglian Li³, Marco Maccarana³, Wei Zhang⁴, Deling Shi⁵, Ying Kan⁶, Xiao Zhang⁷, Lianli Chi⁵, Ulf Lindahl³, Hongmei Li⁸, Jin-Ping Li⁹, Tianwei Tan¹⁰

Affiliations

¹ Division of Chemistry and Analytical Science, National Institute of Metrology, Beijing, China; College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China; Key Laboratory of Chemical Metrology and Applications on Nutrition and Health for State Market Regulation, China.
² School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, China; Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, China.
³ Department of Medical Biochemistry and Microbiology, University of Uppsala, Uppsala, Sweden.
⁴ Division of Chemistry and Analytical Science, National Institute of Metrology, Beijing, China.
⁵ National Glycoengineering Research Center, Shandong University, Jinan, China.
⁶ Division of Chemistry and Analytical Science, National Institute of Metrology, Beijing, China; Key Laboratory of Chemical Metrology and Applications on Nutrition and Health for State Market Regulation, China.
⁷ Department of Neuroscience, University of Uppsala, Uppsala, Sweden.
⁸ Division of Chemistry and Analytical Science, National Institute of Metrology, Beijing, China; Key Laboratory of Chemical Metrology and Applications on Nutrition and Health for State Market Regulation, China. Electronic address: lihm@nim.ac.cn.
⁹ Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, China; Department of Medical Biochemistry and Microbiology, University of Uppsala, Uppsala, Sweden. Electronic address: Jin-ping.Li@imbim.uu.se.
¹⁰ College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China. Electronic address: twtan@mail.buct.edu.cn.

PMID: 36876765
DOI: 10.1016/j.carbpol.2022.120191

Abstract

Glucuronyl 5-epimerase (Hsepi) converts D-glucuronic acid (GlcA) into L-iduronic acid (IdoA) units, through a mechanism involving reversible abstraction of a proton at C5 of hexuronic acid residues. Incubations of a [4GlcAβ1-4GlcNSO₃α1-]_n precursor substrate with recombinant enzymes in a D₂O/H₂O medium enabled an isotope exchange approach to the assessment of functional interactions of Hsepi with hexuronyl 2-O-sulfotransferase (Hs2st) and glucosaminyl 6-O-sulfotransferase (Hs6st), both involved in the final polymer-modification steps. Enzyme complexes were supported by computational modeling and homogeneous time resolved fluorescence. GlcA and IdoA D/H ratios related to product composition revealed kinetic isotope effects that were interpreted in terms of efficiency of the coupled epimerase and sulfotransferase reactions. Evidence for a functional Hsepi/Hs6st complex was provided by selective incorporation of D atoms into GlcA units adjacent to 6-O-sulfated glucosamine residues. The inability to achieve simultaneous 2-O- and 6-O-sulfation in vitro supported topologically separated reactions in the cell. These findings provide novel insight into the roles of enzyme interactions in heparan sulfate biosynthesis.

Keywords: 2-O-sulfotransferase; 6-Osulfotransferase; Glucuronosyl C5-epimerase; Heparan sulfate.

MeSH terms

Glucuronic Acid
Heparitin Sulfate
Iduronic Acid*
Multienzyme Complexes*
Polymers
Protons
Racemases and Epimerases
Sulfotransferases

Substances

Multienzyme Complexes
Glucuronic Acid
Iduronic Acid
Polymers
Protons
Racemases and Epimerases
Sulfotransferases
Heparitin Sulfate