β-Amanitin is a 16-residue short cyclic polypeptide and a toxin found in the poisonous Amanita phalloides mushroom. β-Amanitin acts as a specific and potent inhibitor of eukaryotic RNA polymerase II and a mild inhibitor of RNA polymerase III. β-Amanitin may be used as a cytotoxic warhead in antibody-drug conjugates (ADCs).
Physicochemical Properties
| Molecular Formula | C₃₉H₅₃N₉O₁₅S |
| Molecular Weight | 919.95 |
| Exact Mass | 919.338 |
| CAS # | 21150-22-1 |
| PubChem CID | 2276 |
| Appearance | White to off-white solid powder |
| Index of Refraction | 1.695 |
| LogP | -3.8 |
| Hydrogen Bond Donor Count | 13 |
| Hydrogen Bond Acceptor Count | 16 |
| Rotatable Bond Count | 7 |
| Heavy Atom Count | 64 |
| Complexity | 1840 |
| Defined Atom Stereocenter Count | 0 |
| InChi Key | IEQCUEXVAPAFMQ-UHFFFAOYSA-N |
| InChi Code | InChI=1S/C39H53N9O15S/c1-4-16(2)31-36(60)41-11-28(53)42-25-15-64(63)38-21(20-6-5-18(50)7-22(20)45-38)9-23(33(57)40-12-29(54)46-31)43-37(61)32(17(3)27(52)14-49)47-35(59)26-8-19(51)13-48(26)39(62)24(10-30(55)56)44-34(25)58/h5-7,16-17,19,23-27,31-32,45,49-52H,4,8-15H2,1-3H3,(H,40,57)(H,41,60)(H,42,53)(H,43,61)(H,44,58)(H,46,54)(H,47,59)(H,55,56) |
| Chemical Name | 2-[34-butan-2-yl-13-(3,4-dihydroxybutan-2-yl)-8,22-dihydroxy-2,5,11,14,27,30,33,36,39-nonaoxo-27λ4-thia-3,6,12,15,25,29,32,35,38-nonazapentacyclo[14.12.11.06,10.018,26.019,24]nonatriaconta-18(26),19(24),20,22-tetraen-4-yl]acetic acid |
| Synonyms | β-Amanitin β Amanitin |
| HS Tariff Code | 2934.99.9001 |
| Storage |
Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment, avoid exposure to moisture. |
| Shipping Condition | Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs) |
Biological Activity
| ln Vitro | β-amanitine (0.01-100 µg/mL; 36 hours) proved harmful to MCF-7 cells. Cell viability at a concentration of 100 was determined to be 52%, 62%, 84%, 86%, and 91%. Ten, one, 0.1, and 0.01 µg/mL, in that order [2]. At two dosages (10 µg/mL and 1 µg/mL) for a full day, β-amanitin significantly inhibits protein synthesis in MCF-7 cells [2]. |
| Cell Assay |
Cell Viability Assay [2] Cell Types: MCF-7 Cell Tested Concentrations: 0.01, 0.1, 1, 10, 100 µg/mL Incubation Duration: 36 hrs (hours) Experimental Results: demonstrated toxicity to MCF-7 cells. |
| ADME/Pharmacokinetics |
Metabolism / Metabolites Free toxin may be removed by opsonization via the reticuloendothelial system (primarily the liver and kidneys) or it may be degraded through cellular internalization via the lysosomes. Lysosomes are membrane-enclosed organelles that contain an array of digestive enzymes, including several proteases. |
| Toxicity/Toxicokinetics |
Toxicity Summary The major toxic mechanism of amatoxins is the inhibition of RNA polymerase II, a vital enzyme in the synthesis of messenger RNA (mRNA), microRNA, and small nuclear RNA (snRNA). Without mRNA, essential protein synthesis, and hence cell metabolism, grind to a halt and the cell dies. (L1774) Toxicity Data LD50: 0.5 mg/kg (Mouse) (T258) |
| References |
[1]. Evaluation and comparison of alpha- and beta-amanitin toxicity on MCF-7 cell line. Turk J Med Sci. 2014;44(5):728-32. [2]. Alpha- and Beta-Amanitin Total Synthesis. Angew Chem Int Ed Engl. 2020 Feb 24. |
| Additional Infomation |
beta-Amanitin is one of a group of at least eight Amatoxins found in several genera of poisonous mushrooms, most notably Amanita phalloides and several other members of the genus Amanita, as well as some Conocybe, Galerina and Lepiota mushroom species. (L1774) See also: beta-Amanitin (annotation moved to). |
Solubility Data
| Solubility (In Vitro) | May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples |
| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently. (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 1.0870 mL | 5.4351 mL | 10.8702 mL | |
| 5 mM | 0.2174 mL | 1.0870 mL | 2.1740 mL | |
| 10 mM | 0.1087 mL | 0.5435 mL | 1.0870 mL |