Structural highlights
Function
[PYGM_RABIT] Phosphorylase is an important allosteric enzyme in carbohydrate metabolism. Enzymes from different sources differ in their regulatory mechanisms and in their natural substrates. However, all known phosphorylases share catalytic and structural properties.
Publication Abstract from PubMed
C-Glucopyranosyl imidazoles, thiazoles, and an N-glucopyranosyl tetrazole were assessed in vitro and ex vivo for their inhibitory efficiency against isoforms of glycogen phosphorylase (GP; a validated pharmacological target for the development of anti-hyperglycaemic agents). Imidazoles proved to be more potent inhibitors than the corresponding thiazoles or the tetrazole. The most potent derivative has a 2-naphthyl substituent, a Ki value of 3.2 microM for hepatic glycogen phosphorylase, displaying also 60% inhibition of GP activity in HepG2 cells, compared to control vehicle treated cells, at 100 muM. X-Ray crystallography studies of the protein - inhibitor complexes revealed the importance of the architecture of inhibitor associated hydrogen bonds or sulfur sigma-hole bond interactions to Asn284 OD1, offering new insights to structure-based design efforts. Moreover, while the 2-glucopyranosyl-tetrazole seems to bind differently from the corresponding 1,2,3-triazole compound, the two inhibitors are equipotent.
The architecture of hydrogen and sulfur sigma-hole interactions explain differences in the inhibitory potency of C-beta-d-glucopyranosyl thiazoles, imidazoles and an N-beta-d glucopyranosyl tetrazole for human liver glycogen phosphorylase and offer new insights to structure-based design.,Kyriakis E, Karra AG, Papaioannou O, Solovou T, Skamnaki VT, Liggri PGV, Zographos SE, Szennyes E, Bokor E, Kun S, Psarra AG, Somsak L, Leonidas DD Bioorg Med Chem. 2020 Jan 1;28(1):115196. doi: 10.1016/j.bmc.2019.115196. Epub, 2019 Nov 14. PMID:31767404[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Kyriakis E, Karra AG, Papaioannou O, Solovou T, Skamnaki VT, Liggri PGV, Zographos SE, Szennyes E, Bokor E, Kun S, Psarra AG, Somsak L, Leonidas DD. The architecture of hydrogen and sulfur sigma-hole interactions explain differences in the inhibitory potency of C-beta-d-glucopyranosyl thiazoles, imidazoles and an N-beta-d glucopyranosyl tetrazole for human liver glycogen phosphorylase and offer new insights to structure-based design. Bioorg Med Chem. 2020 Jan 1;28(1):115196. doi: 10.1016/j.bmc.2019.115196. Epub, 2019 Nov 14. PMID:31767404 doi:http://dx.doi.org/10.1016/j.bmc.2019.115196
