Structural highlights
1s0b is a 1 chain structure with sequence from Clostridium botulinum. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Ligands: | |
| Related: | 1epw, 1g9a, 1s0c, 1s0d, 1s0e, 1s0f, 1s0g |
| Activity: | Bontoxilysin, with EC number 3.4.24.69 |
| Resources: | FirstGlance, OCA, RCSB, PDBsum |
Function
[BXB_CLOBO] Botulinum toxin acts by inhibiting neurotransmitter release. It binds to peripheral neuronal synapses, is internalized and moves by retrograde transport up the axon into the spinal cord where it can move between postsynaptic and presynaptic neurons. It inhibits neurotransmitter release by acting as a zinc endopeptidase that cleaves the '76-Gln-|-Phe-77' bond of synaptobrevin-2.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Clostridium botulinum neurotoxins are the most potent toxins to humans and cause paralysis by blocking neurotransmitter release at the presynaptic nerve terminals. The toxicity involves four steps, viz., binding to neuronal cells, internalization, translocation, and catalytic activity. While the catalytic activity is a zinc endopeptidase activity on the SNARE complex proteins, the translocation is believed to be a pH-dependent process allowing the translocation domain to change its conformation to penetrate the endosomal membrane. Here, we report the crystal structures of botulinum neurotoxin type B at various pHs and of an apo form of the neurotoxin, and discuss the role of metal ions and the effect of pH variation in the biological activity. Except for the perturbation of a few side chains, the conformation of the catalytic domain is unchanged in the zinc-depleted apotoxin, suggesting that zinc's role is catalytic. We have also identified two calcium ions in the molecule and present biochemical evidence to show that they play a role in the translocation of the light chain through the membrane.
Role of metals in the biological activity of Clostridium botulinum neurotoxins.,Eswaramoorthy S, Kumaran D, Keller J, Swaminathan S Biochemistry. 2004 Mar 2;43(8):2209-16. PMID:14979717[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Eswaramoorthy S, Kumaran D, Keller J, Swaminathan S. Role of metals in the biological activity of Clostridium botulinum neurotoxins. Biochemistry. 2004 Mar 2;43(8):2209-16. PMID:14979717 doi:10.1021/bi035844k
