THIOLUTIN

Description

Thiolutin is a natural dithiol that reversibly inhibits bacterial and yeast RNA polymerases (IC₅₀ = 3 μg/ml). Because of this, it can be used for the analysis of mRNA stability. Thiolutin also inhibits endothelial cell adhesion (IC₅₀ < 1 μM) and S180 tumor-induced angiogenesis in mice by inhibiting Hsp27 interactions with cytoskeletal elements.

Chemical Properties

Yellow solid

Uses

Thiolutin has been used as a polymerase II inhibitor:

• to study its effects on yeast cells to calculate transcript half-life
• to study its effects on transcription during germination in budding yeast
• to study its effects on cell adhesion in zebrafish

Uses

Thiolutin is an antibiotic first described by Tanner and co-workers in 1950. Resurgent interest in this class of microbial metabolites was stimulated by the discovery of their selective antitumour activity. Thiolutin is a potent inhibitor of bacterial and yeast RNA polymerases, and also inhibits mannan and glucan formation in fungi. Thiolutin suppresses tumour cell-induced angiogenesis in vivo.

Uses

Thiolutin is an antibiotic isolated from several strains of Streptomyces albus. Thiolutin is a natural dithiol that reversibly inhibits bacterial and yeast RNA polymerases.

Definition

ChEBI: Thiolutin is a dithiolopyrrolone antibiotic that is 4,5-dihydro[1,2]dithiolo[4,3-b]pyrrole in which the hydrogens at positions 4,5 and 6 have been replaced by methyl, oxo and acetamido groups, respectively. It is a potent inhibitor of RNA polymerases, inhibits the angiogenesis of human umbilical vein endothelial cells, and also inhibits JAMM metalloproteases. It has a role as an angiogenesis inhibitor, a chelator, a protein synthesis inhibitor, an EC 2.7.7.6 (RNA polymerase) inhibitor, an antibacterial agent, a toxin, a marine metabolite, a bacterial metabolite, an antifungal agent and an antineoplastic agent. It is a dithiolopyrrolone antibiotic and a member of acetamides. It is functionally related to a holomycin.

Biological Activity

Antibiotic; inhibits bacterial RNA polymerase. Inhibits adhesion of HUVEC cells to vitronectin (IC 50 = 0.83 mM) and subsequently reduces paxillin levels. Suppresses tumor cell-induced angiogenesis.

Biochem/physiol Actions

Sulfur-containing antibiotic, which is a potent inhibitor of bacterial and yeast RNA polymerases. It was found to inhibit in vitro RNA synthesis directed by all three yeast RNA polymerases (I, II, and III). Thiolutin is also an inhibitor of mannan and glucan formation in Saccharomyces cerevisiae and used for the analysis of mRNA stability. Studies have shown that thiolutin inhibits adhesion of human umbilical vein endothelial cells (HUVECs) to vitronectin and thus suppresses tumor cell-induced angiogenesis in vivo.

Safety Profile

Poison by ingestion andsubcutaneous routes. When heated to decomposition itemits very toxic fumes of NOx and SOx.

References

Jing et al. (2021), Blockade of deubiquitinating enzyme PSMD14 overcomes chemoresistance in head and neck squamous cell carcinoma by antagonizing E2F1/Akt/SOX2-mediated stemness; Theranostics, 11 2655 Jia et al. (2010), Thiolutin inhibits endothelial cell adhesion by perturbing Hsp27 interactions with components of the actin and intermediate filament cytoskeleton; Cell Stress Chaperones 15 165 Minamiguchi et al. (2001), Thiolutin, an inhibitor of HUVEC adhesion to vitronectin, reduces paxillin in HUVECs and suppresses tumor cell-induced angiogenesis; Int. J. Cancer, 93 307