7Q5I

A glucose-based molecular rotor probes the catalytic site of glycogen phosphorylase.

This is a non-PDB format compatible entry.

Summary for 7Q5I

• Entry DOI: 10.2210/pdb7q5i/pdb
• Descriptor: Glycogen phosphorylase, muscle form, 2-cyano-3-[4-(dimethylamino)phenyl]-~{N}-[(2~{R},3~{R},4~{S},5~{S},6~{R})-6-(hydroxymethyl)-3,4,5-tris(oxidanyl)oxan-2-yl]propanamide, CARBONATE ION, ... (5 entities in total)
• Functional Keywords: glycogen phosphorylase, inhibitor, type 2 diabetes, molecular rotors, sugar binding protein
• Biological source: Oryctolagus cuniculus (rabbit)
• Total number of polymer chains: 1
• Total formula weight: 98286.07

Authors

Neofytos, D.D.,Chrysina, E.D. (deposition date: 2021-11-03, release date: 2022-03-02, Last modification date: 2024-01-31)

Primary citation

Minadakis, M.P.,Mavreas, K.F.,Neofytos, D.D.,Paschou, M.,Kogkaki, A.,Athanasiou, V.,Mamais, M.,Veclani, D.,Iatrou, H.,Venturini, A.,Chrysina, E.D.,Papazafiri, P.,Gimisis, T.
A glucose-based molecular rotor inhibitor of glycogen phosphorylase as a probe of cellular enzymatic function.
Org.Biomol.Chem., 20:2407-2423, 2022

PubMed Abstract: Molecular rotors belong to a family of fluorescent compounds characterized as molecular switches, where a fluorescence on/off signal signifies a change in the molecule's microenvironment. Herein, the successful synthesis and detailed study of ()-2-cyano-3-(-(dimethylamino)phenyl)--(β-D-glucopyranosyl)acrylamide (RotA), is reported. RotA was found to be a strong inhibitor of rabbit muscle glycogen phosphorylase (RMGP), that binds at the catalytic site of the enzyme. RotA's interactions with the residues lining the catalytic site of RMGP were determined by X-ray crystallography. Spectroscopic studies coupled with theoretical calculations proved that RotA is a molecular rotor. When bound in the catalytic channel of RMGP, it behaved as a light switch, generating a strong fluorescence signal, allowing utilization of RotA as a probe that locates glycogen phosphorylase (GP). RotA, mono-, di- and per-acetylated derivatives, as well as nanoparticles with RotA encapsulated in polyethylene glycol-poly-L-histidine, were used in live cell fluorescence microscopy imaging to test the delivery of RotA through the plasma membrane of HepG2 and A431 cells, with the nanoparticles providing the best results. Once in the intracellular milieu, RotA exhibits remarkable colocalization with GP and significant biological effects, both in cell growth and inhibition of GP.

PubMed: 35119451
DOI: 10.1039/d1ob02211c

Experimental method

X-RAY DIFFRACTION (1.8 Å)