139710-25-1Relevant articles and documents
Structure and mechanism of the ER-based glucosyltransferase ALG6
Bloch, Jo?l S.,Pesciullesi, Giorgio,Boilevin, Jérémy,Nosol, Kamil,Irobalieva, Rossitza N.,Darbre, Tamis,Aebi, Markus,Kossiakoff, Anthony A.,Reymond, Jean-Louis,Locher, Kaspar P.
, p. 443 - 447 (2020)
In eukaryotic protein N-glycosylation, a series of glycosyltransferases catalyse the biosynthesis of a dolichylpyrophosphate-linked oligosaccharide before its transfer onto acceptor proteins1. The final seven steps occur in the lumen of the endoplasmic reticulum (ER) and require dolichylphosphate-activated mannose and glucose as donor substrates2. The responsible enzymes—ALG3, ALG9, ALG12, ALG6, ALG8 and ALG10—are glycosyltransferases of the C-superfamily (GT-Cs), which are loosely defined as containing membrane-spanning helices and processing an isoprenoid-linked carbohydrate donor substrate3,4. Here we present the cryo-electron microscopy structure of yeast ALG6 at 3.0?? resolution, which reveals a previously undescribed transmembrane protein fold. Comparison with reported GT-C structures suggests that GT-C enzymes contain a modular architecture with a conserved module and a variable module, each with distinct functional roles. We used synthetic analogues of dolichylphosphate-linked and dolichylpyrophosphate-linked sugars and enzymatic glycan extension to generate donor and acceptor substrates using purified enzymes of the ALG pathway to recapitulate the activity of ALG6 in vitro. A second cryo-electron microscopy structure of ALG6 bound to an analogue of dolichylphosphate-glucose at 3.9?? resolution revealed the active site of the enzyme. Functional analysis of ALG6 variants identified a catalytic aspartate residue that probably acts as a general base. This residue is conserved in the GT-C superfamily. Our results define the architecture of ER-luminal GT-C enzymes and provide a structural basis for understanding their catalytic mechanisms.
TOLL-LIKE RECEPTOR 9 AGONISTS
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Page/Page column 33, (2009/02/10)
The present invention provides TLR9 agonists comprising, as an active ingredient, a compound represented by formula (I): (wherein a represents 0 or 1; n represents an integer of 0 to 2; m represents an integer of 0 to 5; X1 and X2 each independently represent a hydrogen atom or hydroxy; Y represents an oxygen atom or a sulfur atom; -Q1-represents -O- or the like; -Q2- represents -O- or the like; -Z- represents -O- or the like; R1, R3 and R4 each independently represent hydroxy or the like; R2 and R5 each independently represent a hydrogen atom, hydroxy or the like; and A represents 6-aminopurin-9-yl or the like) or a pharmaceutically acceptable salt thereof, and the like.
Peptidodisaccharides as oligosaccharide mimetics
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, (2008/06/13)
Methods are provided to replace the ether oxygen linkage of oligosaccharides with a peptide link, --NHC(O)--, where the nitrogen atom is linked to the anomeric carbon atom of the sugar. A new family of building blocks for combinational synthesis, peptidodisaccharides, is provided containing the peptide linkage. Synthesis is more facile than with the oxygen-linked carbohydrates; the resulting compounds are expected to be more stable to enzymatic and chemical hydrolysis and to be amenable to automated synthesis.