Taxonomic group: bacteria / Firmicutes
(Phylum: Firmicutes)
Associated disease: Crohn disease [ICD11:
DD70 
]
NCBI PubMed ID: 34229203Publication DOI: 10.1016/j.carres.2021.108384Journal NLM ID: 0043535Publisher: Elsevier
Correspondence: mbalaram
iiserkol.ac.in
Institutions: Sweet Lab, Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, Nadia, 741246, India
Microorganisms present in the guts are the causative agents for various diseases in humans. More and more studies are correlating such diseases and the responsible microorganism. The Gram-positive bacterium Ruminococcus gnavus (R. gnavus) has been identified to be responsible for symptoms of Crohn's disease. R. gnavas produces a glucorhamnan polysaccharide and it is postulated that this polysaccharide induces inflammatory response through toll-like receptor 4 (TLR4). The current manuscript describes the chemical synthesis of the pentasaccharide repeating unit of the O-polysachharide from R. gnavus. The major challenge associated with this particular synthesis is the presence of two consecutive 1,2-cis glucose units. The target oligosaccharide is achieved through a linear strategy from commercially available sugars through rational protecting group manipulation. 1,2-cis glycosylation of glucose through remote participation of acyl group at the 6-O position is used successfully with excellent yield. In both cases, sole 1,2-cis products are obtained at -20 °C through the activation of thioglycosides.
1, total synthesis, 2-cis glucosylation, Crohn's disease, R.gnavus, remote participation
Structure type: polymer chemical repeating unit
Location inside paper: Fig. 1, pentasaccharide repeating unit X
Trivial name: glucorhamnan
Compound class: O-polysaccharide
Contained glycoepitopes: IEDB_133754,IEDB_136105,IEDB_142488,IEDB_144998,IEDB_146664,IEDB_2116141,IEDB_225177,IEDB_885823,IEDB_983931,SB_192
Methods: 13C NMR, 1H NMR, TLC, chemical synthesis, HPLC, glycosylation, optical rotation measurement, HR-ESI-MS, flash chromatography
Biological activity: a glucorhamnan polysaccharide is to be responsible for symptoms of Crohn’s disease
Related record ID(s): 9719
NCBI Taxonomy refs (TaxIDs): 33038
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
report error