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Fasciculin-2, Fas-2, Fas2, FAS-II, Toxin TA1, Acetylcholinesterase toxin F-VII, fasciculin, fasciculin II, fasciculin 2

A Selective, Potent and Reversible Blocker of Acetylcholinesterase

Cat #: F-225
Alternative Name Fasciculin-2, Fas-2, Fas2, FAS-II, Toxin TA1, Acetylcholinesterase toxin F-VII, fasciculin, fasciculin II, fasciculin 2
Lyophilized Powder yes
  • Bioassay Tested
  • Origin Natural peptide isolated from Dendroaspis angusticeps (Eastern green mamba).
    MW: 6749 Da
    Purity: >99% (HPLC)
    Effective concentration 1-10 nM.
    Modifications Disulfide bonds between Cys3-Cys22, Cys17-Cys39, Cys41-Cys52 and Cys53-Cys59.
    Molecular formula C276H438N88O90S10.
    CAS No.: 95506-56-2
    Activity Fasciculin-II selectively and potently binds and inhibits acetylcholinesterase.
    1. Anglister, L. et al. (1978) J. Mol. Biol. 125, 293.
    2. Ellman, G.L. et al. (1961) Biochem. Pharmacol. 7, 88.
    Shipping and storage Shipped at room temperature. Product as supplied can be stored intact at room temperature for several weeks. For longer periods, it should be stored at -20°C.
    Solubility Any conventional buffer. Centrifuge all product preparations before use (10000 x g 5 min).
    Storage of solutions Up to two weeks at 4°C or six months at -20°C.
    Our bioassay
    • Alomone Labs Fasciculin-II potently inhibits Acetylcholinesterase (AChE) activity. 
      Alomone Labs Fasciculin-II potently inhibits Acetylcholinesterase (AChE) activity. 
      AChE activity was determined colorimetrically using Ellman's reagent, as production of thiocholine from acetylthiocholine. Absorbance was measured at 405 nm after a 30 min incubation. Normalized activity of 100 mU/ml (green) and 400 mU/ml (black) human AChE, as per cent of control, was plotted against increasing concentrations of Fasciculin-II (#F-225), showing concentration-dependent inhibition with pIC50 ≈ 6.7-6.5.
    References - Scientific background
    1. Anglister, L. et al. (1978) J. Mol. Biol. 125, 293.
    2. Karlsson, E. et al. (1986) Pharmacol. Ther. 30, 259.
    3. Ellman, G.L. et al. (1961) Biochem. Pharmacol. 7, 88.
    Scientific background

    Fasciculin-II is a 61 amino acid peptidyl toxin with four disulfide bonds, isolated from the Eastern green mamba (Dendroaspis angusticeps) venom. Fasciculin-II belongs to the three finger protein of Elapidae toxin family. Fasciculin-II differs from Fasciculin-I only at one position by a replacement of Tyr with Asp or Asn1.

    Fasciculin-II was shown to be a selective potent and reversible blocker of acetylcholinesterase by binding to the peripheral site of the enzyme1. Injection of Fasciculin-II to mice causes severe, generalized, and long-lasting twitching (fasciculation) due to its ability to prevent degradation and therefore promote acetylcholine accumulation at the neuromuscular junction2.

    Net Peptide Content: 100%
    Last update: 08/06/2021

    Fasciculin-II (#F-225) is a highly pure, natural, and biologically active peptide toxin.

    For research purposes only, not for human use



    Scientific Background


    Product citations
    1. Wen, H. et al. (2016) Proc. Natl. Acad. Sci. U.S.A. 113, E378.
    2. Wen, H. et al. (2016) J. Neurosci. 36, 10870.
    3. Robinson, K.G. et al. (2013) Am. J. Med. Genet. A 161A, 3042.
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