5v8p

From Proteopedia

Small Molecule Inhibitor ABS-143 Bound to the Botulinum Neurotoxin Serotype A Light Chain

Structural highlights

5v8p is a 2 chain structure with sequence from Clostridium botulinum. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.501Å
Ligands:	,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

BXA1_CLOBH Inhibits acetylcholine release. The botulinum toxin binds with high affinity to peripheral neuronal presynaptic membrane to the secretory vesicle protein SV2. It binds directly to the largest luminal loop of SV2A, SV2B and SV2C. It is then internalized by receptor-mediated endocytosis. The C-terminus of the heavy chain (H) is responsible for the adherence of the toxin to the cell surface while the N-terminus mediates transport of the light chain from the endocytic vesicle to the cytosol. After translocation, the light chain (L) hydrolyzes the 197-Gln-|-Arg-198 bond in SNAP-25, thereby blocking neurotransmitter release. Inhibition of acetylcholine release results in flaccid paralysis, with frequent heart or respiratory failure.

Publication Abstract from PubMed

Botulinum neurotoxins (BoNTs) are the most toxic substances known to mankind and are the causative agents of the neuroparalytic disease botulism. Their ease of production and extreme toxicity have caused these neurotoxins to be classified as Tier 1 bioterrorist threat agents and have led to a sustained effort to develop countermeasures to treat intoxication in case of a bioterrorist attack. While timely administration of an approved antitoxin is effective in reducing the severity of botulism, reversing intoxication requires different strategies. In the present study, we evaluated ABS 252 and other mercaptoacetamide small molecule active-site inhibitors of BoNT/A light chain using an integrated multi-assay approach. ABS 252 showed inhibitory activity in enzymatic, cell-based and muscle activity assays, and importantly, produced a marked delay in time-to-death in mice. The results suggest that a multi-assay approach is an effective strategy for discovery of potential BoNT therapeutic candidates.

Small molecule metalloprotease inhibitor with in vitro, ex vivo and in vivo efficacy against botulinum neurotoxin serotype A.,Jacobson AR, Adler M, Silvaggi NR, Allen KN, Smith GM, Fredenburg RA, Stein RL, Park JB, Feng X, Shoemaker CB, Deshpande SS, Goodnough MC, Malizio CJ, Johnson EA, Pellett S, Tepp WH, Tzipori S Toxicon. 2017 Jul 8;137:36-47. doi: 10.1016/j.toxicon.2017.06.016. PMID:28698055^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Jacobson AR, Adler M, Silvaggi NR, Allen KN, Smith GM, Fredenburg RA, Stein RL, Park JB, Feng X, Shoemaker CB, Deshpande SS, Goodnough MC, Malizio CJ, Johnson EA, Pellett S, Tepp WH, Tzipori S. Small molecule metalloprotease inhibitor with in vitro, ex vivo and in vivo efficacy against botulinum neurotoxin serotype A. Toxicon. 2017 Jul 8;137:36-47. doi: 10.1016/j.toxicon.2017.06.016. PMID:28698055 doi:http://dx.doi.org/10.1016/j.toxicon.2017.06.016