| IED ID | IndEnz0002006983 |
| Enzyme Type ID | protease006983 |
| Protein Name |
Botulinum neurotoxin type A2 BoNT/A Bontoxilysin-A BOTOX Cleaved into: Botulinum neurotoxin A2 light chain LC EC 3.4.24.69 ; Botulinum neurotoxin A2 heavy chain HC |
| Gene Name | botA atx bna bonT CLM_0897 |
| Organism | Clostridium botulinum (strain Kyoto / Type A2) |
| Taxonomic Lineage | cellular organisms Bacteria Terrabacteria group Firmicutes Clostridia Eubacteriales Clostridiaceae Clostridium Clostridium botulinum Clostridium botulinum A Clostridium botulinum (strain Kyoto / Type A2) |
| Enzyme Sequence | MPFVNKQFNYKDPVNGVDIAYIKIPNAGQMQPVKAFKIHNKIWVIPERDTFTNPEEGDLNPPPEAKQVPVSYYDSTYLSTDNEKDNYLKGVTKLFERIYSTDLGRMLLTSIVRGIPFWGGSTIDTELKVIDTNCINVIQPDGSYRSEELNLVIIGPSADIIQFECKSFGHDVLNLTRNGYGSTQYIRFSPDFTFGFEESLEVDTNPLLGAGKFATDPAVTLAHELIHAEHRLYGIAINPNRVFKVNTNAYYEMSGLEVSFEELRTFGGHDAKFIDSLQENEFRLYYYNKFKDVASTLNKAKSIIGTTASLQYMKNVFKEKYLLSEDTSGKFSVDKLKFDKLYKMLTEIYTEDNFVNFFKVINRKTYLNFDKAVFRINIVPDENYTIKDGFNLKGANLSTNFNGQNTEINSRNFTRLKNFTGLFEFYKLLCVRGIIPFKTKSLDEGYNKALNDLCIKVNNWDLFFSPSEDNFTNDLDKVEEITADTNIEAAEENISLDLIQQYYLTFDFDNEPENISIENLSSDIIGQLEPMPNIERFPNGKKYELDKYTMFHYLRAQEFEHGDSRIILTNSAEEALLKPNVAYTFFSSKYVKKINKAVEAFMFLNWAEELVYDFTDETNEVTTMDKIADITIIVPYIGPALNIGNMLSKGEFVEAIIFTGVVAMLEFIPEYALPVFGTFAIVSYIANKVLTVQTINNALSKRNEKWDEVYKYTVTNWLAKVNTQIDLIREKMKKALENQAEATKAIINYQYNQYTEEEKNNINFNIDDLSSKLNESINSAMININKFLDQCSVSYLMNSMIPYAVKRLKDFDASVRDVLLKYIYDNRGTLVLQVDRLKDEVNNTLSADIPFQLSKYVDNKKLLSTFTEYIKNIVNTSILSIVYKKDDLIDLSRYGAKINIGDRVYYDSIDKNQIKLINLESSTIEVILKNAIVYNSMYENFSTSFWIKIPKYFSKINLNNEYTIINCIENNSGWKVSLNYGEIIWTLQDNKQNIQRVVFKYSQMVNISDYINRWIFVTITNNRLTKSKIYINGRLIDQKPISNLGNIHASNKIMFKLDGCRDPRRYIMIKYFNLFDKELNEKEIKDLYDSQSNSGILKDFWGNYLQYDKPYYMLNLFDPNKYVDVNNIGIRGYMYLKGPRGSVVTTNIYLNSTLYEGTKFIIKKYASGNEDNIVRNNDRVYINVVVKNKEYRLATNASQAGVEKILSALEIPDVGNLSQVVVMKSKDDQGIRNKCKMNLQDNNGNDIGFIGFHLYDNIAKLVASNWYNRQVGKASRTFGCSWEFIPVDDGWGESSL |
| Enzyme Length | 1296 |
| Uniprot Accession Number | Q45894 |
| Absorption | |
| Active Site | ACT_SITE 224; /evidence=ECO:0000255|PROSITE-ProRule:PRU10095 |
| Activity Regulation | ACTIVITY REGULATION: Protease activity of LC inhibited by arginine hydroxamate. {ECO:0000269|PubMed:16846233}. |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=Limited hydrolysis of proteins of the neuroexocytosis apparatus, synaptobrevins, SNAP25 or syntaxin. No detected action on small molecule substrates.; EC=3.4.24.69; Evidence={ECO:0000269|PubMed:16846233}; |
| DNA Binding | |
| EC Number | 3.4.24.69 |
| Enzyme Function | FUNCTION: [Botulinum neurotoxin type A2]: Botulinum toxin causes flaccid paralysis by inhibiting neurotransmitter (acetylcholine) release from the presynaptic membranes of nerve terminals of eukaryotic host skeletal and autonomic nervous system, with frequent heart or respiratory failure. Precursor of botulinum neurotoxin A2 which has 2 coreceptors; complex polysialylated gangliosides found on neural tissue and specific membrane-anchored proteins found in synaptic vesicles. Receptor proteins are exposed on host presynaptic cell membrane during neurotransmitter release, when the toxin heavy chain (HC) binds to them. Upon synaptic vesicle recycling the toxin is taken up via the endocytic pathway. When the pH of the toxin-containing endosome drops a structural rearrangement occurs so that the N-terminus of the HC forms pores that allows the light chain (LC) to translocate into the cytosol. Once in the cytosol the disulfide bond linking the 2 subunits is reduced and LC cleaves its target protein on synaptic vesicles, preventing their fusion with the cytoplasmic membrane and thus neurotransmitter release (By similarity). {ECO:0000250|UniProtKB:P0DPI0}.; FUNCTION: [Botulinum neurotoxin A2 light chain]: Has proteolytic activity. After translocation into the eukaryotic host cytosol, LC hydrolyzes the 197-Gln-|-Arg-198 bond in SNAP25, blocking neurotransmitter release (PubMed:16846233). {ECO:0000305|PubMed:16846233}.; FUNCTION: [Botulinum neurotoxin A2 heavy chain]: Responsible for host epithelial cell transcytosis, host nerve cell targeting and translocation of light chain (LC) into host cytosol. Composed of 3 subdomains; the translocation domain (TD), and N-terminus and C-terminus of the receptor-binding domain (RBD). The RBD is responsible for the adherence of the toxin to the cell surface. It simultaneously recognizes 2 coreceptors; polysialated gangliosides and the receptor protein SV2 in close proximity on host synaptic vesicles (PubMed:28252640, PubMed:29649119). The N-terminus of the TD wraps an extended belt around the perimeter of the LC, protecting Zn(2+) in the active site; it may also prevent premature LC dissociation from the translocation channel and to protect toxin prior to translocation (By similarity). The TD inserts into synaptic vesicle membrane to allow translocation into the host cytosol (By similarity). {ECO:0000250|UniProtKB:P0DPI0, ECO:0000269|PubMed:28252640, ECO:0000269|PubMed:29649119}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Active site (1); Beta strand (55); Chain (3); Disulfide bond (2); Helix (19); Initiator methionine (1); Metal binding (3); Motif (1); Mutagenesis (2); Region (4); Site (1); Transmembrane (2); Turn (7) |
| Keywords | 3D-structure;Disulfide bond;Host cell junction;Host cell membrane;Host cytoplasm;Host cytoplasmic vesicle;Host membrane;Host synapse;Hydrolase;Membrane;Metal-binding;Metalloprotease;Neurotoxin;Protease;Secreted;Toxin;Transmembrane;Transmembrane helix;Virulence;Zinc |
| Interact With | |
| Induction | |
| Subcellular Location | SUBCELLULAR LOCATION: [Botulinum neurotoxin A2 light chain]: Secreted. Host cytoplasm, host cytosol {ECO:0000305|PubMed:16846233}.; SUBCELLULAR LOCATION: [Botulinum neurotoxin A2 heavy chain]: Secreted. Host cell junction, host synapse, host presynaptic cell membrane {ECO:0000305|PubMed:28252640}. Host cytoplasmic vesicle, host secretory vesicle, host synaptic vesicle membrane {ECO:0000250|UniProtKB:P0DPI0}; Multi-pass membrane protein {ECO:0000305}. |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (7) |
| Cross Reference PDB | 1E1H; 2G7K; 2G7N; 2G7P; 2G7Q; 5MOY; 6ES1; |
| Mapped Pubmed ID | - |
| Motif | MOTIF 1264..1267; /note=Host ganglioside-binding motif; /evidence=ECO:0000250|UniProtKB:P0DPI0 |
| Gene Encoded By | |
| Mass | 149,411 |
| Kinetics | BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=14.1 uM for SNAP25 fragment (146-206) with isolated botulinum neurotoxin A2 light chain {ECO:0000269|PubMed:16846233}; Note=kcat is 0.13 sec(-1), for botulinum neurotoxin A2 light chain. {ECO:0000269|PubMed:16846233}; |
| Metal Binding | METAL 223; /note="Zinc; via tele nitrogen; catalytic"; /evidence="ECO:0000269|PubMed:15107500, ECO:0000269|PubMed:16846233, ECO:0007744|PDB:2G7P, ECO:0007744|PDB:2G7Q"; METAL 227; /note="Zinc; via tele nitrogen; catalytic"; /evidence="ECO:0000269|PubMed:15107500, ECO:0000269|PubMed:16846233, ECO:0007744|PDB:2G7P, ECO:0007744|PDB:2G7Q"; METAL 262; /note="Zinc; catalytic"; /evidence="ECO:0000269|PubMed:15107500, ECO:0000269|PubMed:16846233, ECO:0007744|PDB:2G7P, ECO:0007744|PDB:2G7Q" |
| Rhea ID | |
| Cross Reference Brenda |