ID   3S11_DENPO              Reviewed;          60 AA.
AC   P01416;
DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT   21-JUL-1986, sequence version 1.
DT   25-MAY-2022, entry version 103.
DE   RecName: Full=Short neurotoxin 1;
DE   AltName: Full=Neurotoxin alpha;
OS   Dendroaspis polylepis polylepis (Black mamba).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC   Serpentes; Colubroidea; Elapidae; Elapinae; Dendroaspis.
OX   NCBI_TaxID=8620;
RN   [1]
RP   PROTEIN SEQUENCE, AND SUBCELLULAR LOCATION.
RC   TISSUE=Venom;
RX   PubMed=5033401; DOI=10.1016/s0021-9258(19)45135-1;
RA   Strydom D.J.;
RT   "Snake venom toxins. The amino acid sequences of two toxins from
RT   Dendroaspis polylepis polylepis (black mamba) venom.";
RL   J. Biol. Chem. 247:4029-4042(1972).
RN   [2]
RP   STRUCTURE BY NMR, AND DISULFIDE BONDS.
RX   PubMed=2847926; DOI=10.1111/j.1432-1033.1988.tb14376.x;
RA   Labhardt A.L., Hunziker-Kwik E.H., Wuethrich K.;
RT   "Secondary structure determination for alpha-neurotoxin from Dendroaspis
RT   polylepis polylepis based on sequence-specific 1H-nuclear-magnetic-
RT   resonance assignments.";
RL   Eur. J. Biochem. 177:295-305(1988).
RN   [3]
RP   STRUCTURE BY NMR, AND DISULFIDE BONDS.
RX   PubMed=1433289; DOI=10.1016/0022-2836(92)90525-o;
RA   Brown L.R., Wuethrich K.;
RT   "Nuclear magnetic resonance solution structure of the alpha-neurotoxin from
RT   the black mamba (Dendroaspis polylepis polylepis).";
RL   J. Mol. Biol. 227:1118-1135(1992).
CC   -!- FUNCTION: Binds to muscle nicotinic acetylcholine receptor (nAChR) and
CC       inhibit acetylcholine from binding to the receptor, thereby impairing
CC       neuromuscular transmission. {ECO:0000250|UniProtKB:P60775}.
CC   -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:5033401}.
CC   -!- TISSUE SPECIFICITY: Expressed by the venom gland. {ECO:0000305}.
CC   -!- TOXIC DOSE: LD(50) is 0.09 mg/kg by subcutaneous injection.
CC   -!- SIMILARITY: Belongs to the snake three-finger toxin family. Short-chain
CC       subfamily. Type I alpha-neurotoxin sub-subfamily. {ECO:0000305}.
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DR   PIR; A01686; N1EP1D.
DR   PDB; 1NTX; NMR; -; A=1-60.
DR   PDBsum; 1NTX; -.
DR   AlphaFoldDB; P01416; -.
DR   BMRB; P01416; -.
DR   SMR; P01416; -.
DR   EvolutionaryTrace; P01416; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0030550; F:acetylcholine receptor inhibitor activity; IEA:UniProtKB-KW.
DR   GO; GO:0099106; F:ion channel regulator activity; IEA:UniProtKB-KW.
DR   GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
DR   CDD; cd00206; snake_toxin; 1.
DR   Gene3D; 2.10.60.10; -; 1.
DR   InterPro; IPR003571; Snake_3FTx.
DR   InterPro; IPR045860; Snake_toxin-like_sf.
DR   InterPro; IPR018354; Snake_toxin_con_site.
DR   SUPFAM; SSF57302; SSF57302; 1.
DR   PROSITE; PS00272; SNAKE_TOXIN; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Acetylcholine receptor inhibiting toxin;
KW   Direct protein sequencing; Disulfide bond; Ion channel impairing toxin;
KW   Neurotoxin; Postsynaptic neurotoxin; Secreted; Toxin.
FT   CHAIN           1..60
FT                   /note="Short neurotoxin 1"
FT                   /evidence="ECO:0000269|PubMed:5033401"
FT                   /id="PRO_0000093574"
FT   DISULFID        3..22
FT                   /evidence="ECO:0000269|PubMed:1433289,
FT                   ECO:0000269|PubMed:2847926, ECO:0000312|PDB:1NTX"
FT   DISULFID        17..39
FT                   /evidence="ECO:0000269|PubMed:1433289,
FT                   ECO:0000269|PubMed:2847926, ECO:0000312|PDB:1NTX"
FT   DISULFID        41..52
FT                   /evidence="ECO:0000269|PubMed:1433289,
FT                   ECO:0000269|PubMed:2847926, ECO:0000312|PDB:1NTX"
FT   DISULFID        53..58
FT                   /evidence="ECO:0000269|PubMed:1433289,
FT                   ECO:0000269|PubMed:2847926, ECO:0000312|PDB:1NTX"
FT   STRAND          2..4
FT                   /evidence="ECO:0007829|PDB:1NTX"
FT   STRAND          14..16
FT                   /evidence="ECO:0007829|PDB:1NTX"
FT   STRAND          22..28
FT                   /evidence="ECO:0007829|PDB:1NTX"
FT   STRAND          30..40
FT                   /evidence="ECO:0007829|PDB:1NTX"
FT   STRAND          48..55
FT                   /evidence="ECO:0007829|PDB:1NTX"
SQ   SEQUENCE   60 AA;  6915 MW;  E68D6A44410645AC CRC64;
     RICYNHQSTT RATTKSCEEN SCYKKYWRDH RGTIIERGCG CPKVKPGVGI HCCQSDKCNY