Natural product sugar attachments dictate the targeting, biological activity and/or pharmacology of the parent natural product and the alteration of natural product glycosylation patterns has been validated for the generation and/or optimization of natural product-based therapeutics. Yet, simple effective methods to alter sugars appended to natural products are currently lacking. The first phase of this study (RO1 AI52218, years 1-5) led to the development and implementation of a remarkably successful enzymatic strategy to exchange natural product sugars with diverse D-sugar arrays and also provided fundamental information regarding two critical, but poorly understood, enzyme classes (anomeric sugar kinases and sugar-1- phosphate nucleotidylyltransferases). The proposed second phase of this project (years 6-10) is designed to specifically expand this program toward complex natural product L-glycosides. Model GTs have been selected to enable unique studies to probe glycosyltransferase (GT) mechanism with a particular focus upon our recent discovery of the facile reversibility of GT-catalyzed reactions. The enzymes selected - E. coli galK-encoded galactokinase (GalK), Salmonella rmlA-encoded alpha-D-glucose-1-phosphate thymidylyltransferase (RmlA) and a set of GTs which act upon macrolides (MegD1, TylCV and OleD) or nonribosomal peptides (GtfD and GtfE) - are all models for carbohydrate processing reactions ubiquitous in nature and relevant to human disease. Among the many advantages of the targeted natural product scaffolds within this study, differential glycosylation of macrolides and nonribosomal peptides present metabolites with markedly unique antibiotic, antiviral and antiparasitic properties. Cumulatively, the studies described herein will extend our understanding of reactions catalyzed by essential carbohydrate modifying enzymes and offer unprecedented access to uniquely bioactive natural product libraries not readily accessible via conventional organic synthesis or in vivo pathway engineering.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project (R01)
Project #
Application #
Study Section
Synthetic and Biological Chemistry B Study Section (SBCB)
Program Officer
Tseng, Christopher K
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Wisconsin Madison
Schools of Pharmacy
United States
Zip Code
Goff, Randal D; Thorson, Jon S (2014) Neoglycosylation and neoglycorandomization: Enabling tools for the discovery of novel glycosylated bioactive probes and early stage leads. Medchemcomm 5:1036-1047
Zhang, Jianjun; Ponomareva, Larissa V; Marchillo, Karen et al. (2013) Synthesis and antibacterial activity of doxycycline neoglycosides. J Nat Prod 76:1627-36
Gantt, Richard W; Peltier-Pain, Pauline; Singh, Shanteri et al. (2013) Broadening the scope of glycosyltransferase-catalyzed sugar nucleotide synthesis. Proc Natl Acad Sci U S A 110:7648-53
Wang, Fengbin; Zhou, Maoquan; Singh, Shanteri et al. (2013) Crystal structure of SsfS6, the putative C-glycosyltransferase involved in SF2575 biosynthesis. Proteins 81:1277-82
Zhou, Maoquan; Hamza, Adel; Zhan, Chang-Guo et al. (2013) Assessing the regioselectivity of OleD-catalyzed glycosylation with a diverse set of acceptors. J Nat Prod 76:279-86
Peltier-Pain, Pauline; Marchillo, Karen; Zhou, Maoquan et al. (2012) Natural product disaccharide engineering through tandem glycosyltransferase catalysis reversibility and neoglycosylation. Org Lett 14:5086-9
Zhou, Maoquan; Hou, Yanpeng; Hamza, Adel et al. (2012) Probing the regiospecificity of enzyme-catalyzed steroid glycosylation. Org Lett 14:5424-7
Singh, Shanteri; Phillips Jr, George N; Thorson, Jon S (2012) The structural biology of enzymes involved in natural product glycosylation. Nat Prod Rep 29:1201-37
Goff, Randal D; Thorson, Jon S (2012) Enhancement of cyclopamine via conjugation with nonmetabolic sugars. Org Lett 14:2454-7
Williams, Gavin J; Yang, Jie; Zhang, Changsheng et al. (2011) Recombinant E. coli prototype strains for in vivo glycorandomization. ACS Chem Biol 6:95-100

Showing the most recent 10 out of 56 publications