Uridine diphosphate N-acetylglucosamine


Uridine diphosphate N-acetylglucosamine or UDP-GlcNAc is a nucleotide sugar and a coenzyme in metabolism. It is used by glycosyltransferases to transfer N-acetylglucosamine residues to substrates. D-Glucosamine is made naturally in the form of glucosamine-6-phosphate, and is the biochemical precursor of all nitrogen-containing sugars.[1] To be specific, glucosamine-6-phosphate is synthesized from fructose 6-phosphate and glutamine[2] as the first step of the hexosamine biosynthesis pathway.[3] The end-product of this pathway is UDP-GlcNAc, which is then used for making glycosaminoglycans, proteoglycans, and glycolipids.[4]

Uridine diphosphate N-acetylglucosamine
Names
IUPAC name
Uridine 5′-(2-acetamido-2-deoxy-α-D-glucopyranosyl dihydrogen diphosphate)
Systematic IUPAC name
O1-[(2R,3R,4R,5S,6R)-3-Acetamido-4,5-dihydroxy-6-(hydroxymethyl)oxan-2-yl] O3-{[(2R,3S,4R,5R)-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-3,4-dihydroxyoxolan-2-yl]methyl} dihydrogen diphosphate
Other names
UDP-N-acetylglucosamine; UDP-GlcNAc
Identifiers
3D model (JSmol)
  • CC(=O)N[C@@H]1[C@H]([C@@H]([C@H](O[C@@H]1OP(=O)(O)OP(=O)(O)OC[C@@H]2[C@H]([C@H]([C@@H](O2)N3C=CC(=O)NC3=O)O)O)CO)O)O
Properties
C17H27N3O17P2
Molar mass607.355 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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UDP-GlcNAc is extensively involved in intracellular signaling as a substrate for O-linked N-acetylglucosamine transferases (OGTs) to install the O-GlcNAc post-translational modification in a wide range of species. It is also involved in nuclear pore formation and nuclear signalling. OGTs and OG-ases play an important role in the structure of the cytoskeleton. In mammals, there is enrichment of OGT transcripts in the pancreas beta-cells, and UDP-GlcNAc is thought to be part of the glucose sensing mechanism. There is also evidence that it plays a part in insulin sensitivity in other cells. In plants, it is involved in the control of gibberellin production.[5]

Clostridium novyi type A alpha-toxin is an O-linked N-actetylglucosamine transferase acting on Rho proteins and causing the collapse of the cytoskeleton.

References