Tunicamycin

BeschreibungTunicamycin mixture is a mixture of tunicamycins with variable trans-2,3-unsaturated branched chain fatty acid (BFCA) chain lengths. Tunicamycins are anti-microbial agents that are active against Gram-positive bacteria, fungi, and viruses. They inhibit the N-acetylhexosamine (HexNAc) phosphotransferase family of enzymes in bacteria and prevent peptidoglycan biosynthesis. In eukaryotes, they inhibit N-acetylglucosamine (GlcNAc) phosphotransferase (GPT), preventing the first step in N-linked glycosylation and inducing the unfolded protein response and cell death. The cellular toxicity of tunicamycins is linked to the trans-2,3-unsaturated BCFA, and saturated BCFA-containing tunicamycin derivatives, such as TunR1 and TunR2 , have reduced toxicity. Tunicamycins impair glycosylation of the receptor tyrosine kinases EGFR, HER2, HER3, and IGF-1R, which prevents their translocation out of the endoplasmic reticulum and Golgi apparatus and reduces their protein levels and activity. Tunicamycin sensitizes EGFR inhibitor-resistant U251 glioma and Bx/PC-3 pancreatic adenocarcinoma cells to irradiation.

VerwendenThe tunicamycins are a family of lipophilic nucleosides with fatty acids conjugated to an aminoglycoside group. The complex comprises analogues, tunicamycins I to X. This composition is typical of other products less precisely described as tunicamycins A to D. The tunicamycins act by blocking the formation of N-glycoside linkages to proteins via inhibition of formation of dolichol monophosphate from N-acetylglucosamine-1-phosphate. Tunicamycin blocks the synthesis of all N-linked glycoproteins (N-glycans) and causes cell cycle arrest in G1 phase. Tunicamycins are broadly active against prokaryotes, eukaryotes and viruses.