3S1EA_LATSE
ID 3S1EA_LATSE Reviewed; 83 AA.
AC P60775; P01435;
DT 21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT 21-JUL-1986, sequence version 1.
DT 25-MAY-2022, entry version 90.
DE RecName: Full=Erabutoxin a {ECO:0000303|PubMed:4941832, ECO:0000303|PubMed:5166329};
DE Short=ETXA;
DE Short=Ea {ECO:0000303|PubMed:12957382};
DE AltName: Full=Short neurotoxin 1a;
DE Flags: Precursor;
OS Laticauda semifasciata (Black-banded sea krait) (Pseudolaticauda
OS semifasciata).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC Lepidosauria; Squamata; Bifurcata; Unidentata; Episquamata; Toxicofera;
OC Serpentes; Colubroidea; Elapidae; Laticaudinae; Laticauda.
OX NCBI_TaxID=8631;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Venom gland;
RX PubMed=2860927; DOI=10.1016/s0300-9084(85)80046-8;
RA Tamiya T., Lamouroux A., Julien J.-F., Grima B., Mallet J., Fromageot P.,
RA Menez A.;
RT "Cloning and sequence analysis of the cDNA encoding a snake neurotoxin
RT precursor.";
RL Biochimie 67:185-189(1985).
RN [2]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Venom gland;
RA Kariya Y., Araki S., Agu H., Tamiya T., Tsuchiya T.;
RT "Classification of sea snakes in genus Laticauda by nucleotide sequences
RT encoding short chain neurotoxins.";
RL Submitted (SEP-1998) to the EMBL/GenBank/DDBJ databases.
RN [3]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC TISSUE=Liver;
RX PubMed=12957382; DOI=10.1016/s0378-1119(03)00637-1;
RA Fujimi T.J., Nakajyo T., Nishimura E., Ogura E., Tsuchiya T., Tamiya T.;
RT "Molecular evolution and diversification of snake toxin genes, revealed by
RT analysis of intron sequences.";
RL Gene 313:111-118(2003).
RN [4]
RP PROTEIN SEQUENCE OF 22-83, AND SUBCELLULAR LOCATION.
RX PubMed=4941832; DOI=10.1042/bj1220453;
RA Sato S., Tamiya N.;
RT "The amino acid sequences of erabutoxins, neurotoxic proteins of sea-snake
RT (Laticauda semifasciata) venom.";
RL Biochem. J. 122:453-461(1971).
RN [5]
RP SEQUENCE REVISION.
RX PubMed=588261; DOI=10.1042/bj1670289;
RA Maeda N., Tamiya N.;
RT "Correction of partial amino acid sequence of erabutoxins.";
RL Biochem. J. 167:289-291(1977).
RN [6]
RP DISULFIDE BONDS.
RX PubMed=5166329; DOI=10.1042/bj1220463;
RA Endo Y., Sato S., Ishii S., Tamiya N.;
RT "The disulphide bonds of erabutoxin a, a neurotoxic protein of a sea-snake
RT (Laticauda semifasciata) venom.";
RL Biochem. J. 122:463-467(1971).
RN [7]
RP FUNCTION, AND MUTAGENESIS OF SER-29; LYS-48; TRP-50; ASP-52; PHE-53;
RP ARG-54; GLY-55; GLU-59; GLY-70 AND LEU-73.
RX PubMed=8419369; DOI=10.1016/s0021-9258(18)54020-5;
RA Pillet L., Tremeau O., Ducancel F., Drevet P., Zinn-Justin S.,
RA Pinkasfeld S., Boulain J.C., Menez A.;
RT "Genetic engineering of snake toxins. Role of invariant residues in the
RT structural and functional properties of a curaremimetic toxin, as probed by
RT site-directed mutagenesis.";
RL J. Biol. Chem. 268:909-916(1993).
RN [8]
RP FUNCTION, AND MUTAGENESIS OF ASN-26; HIS-27; GLN-28; SER-29; SER-30;
RP GLN-31; PRO-32; GLN-33; THR-34; THR-35; LYS-36; THR-37; SER-39; GLU-42;
RP TYR-46; ASN-47; GLN-49; TRP-50; SER-51; ASP-52; ARG-54; THR-56; ILE-57;
RP GLU-59; PRO-65; THR-66; VAL-67; LYS-68; PRO-69; ILE-71; LYS-72 AND SER-74.
RX PubMed=7721859; DOI=10.1074/jbc.270.16.9362;
RA Tremeau O., Lemaire C., Drevet P., Pinkasfeld S., Ducancel F.,
RA Boulain J.-C., Menez A.;
RT "Genetic engineering of snake toxins. The functional site of Erabutoxin a,
RT as delineated by site-directed mutagenesis, includes variant residues.";
RL J. Biol. Chem. 270:9362-9369(1995).
RN [9]
RP FUNCTION.
RC TISSUE=Venom;
RX PubMed=9305882; DOI=10.1074/jbc.272.39.24279;
RA Servent D., Winckler-Dietrich V., Hu H.-Y., Kessler P., Drevet P.,
RA Bertrand D., Menez A.;
RT "Only snake curaremimetic toxins with a fifth disulfide bond have high
RT affinity for the neuronal alpha7 nicotinic receptor.";
RL J. Biol. Chem. 272:24279-24286(1997).
RN [10]
RP FUNCTION.
RX PubMed=9840221; DOI=10.1016/s0197-0186(98)00033-3;
RA Dajas-Bailador F., Costa G., Dajas F., Emmett S.;
RT "Effects of alpha-erabutoxin, alpha-bungarotoxin, alpha-cobratoxin and
RT fasciculin on the nicotine-evoked release of dopamine in the rat striatum
RT in vivo.";
RL Neurochem. Int. 33:307-312(1998).
RN [11]
RP X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS) OF 22-83.
RX PubMed=265589; DOI=10.1073/pnas.74.3.971;
RA Tsernoglou D., Petsko G.A.;
RT "Three-dimensional structure of neurotoxin a from venom of the Philippines
RT sea snake.";
RL Proc. Natl. Acad. Sci. U.S.A. 74:971-974(1977).
RN [12]
RP X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS) OF 22-83, AND DISULFIDE BONDS.
RX PubMed=2722828; DOI=10.2210/pdb5ebx/pdb;
RA Corfield P.W.R., Lee T.-J., Low B.W.;
RT "The crystal structure of erabutoxin a at 2.0-A resolution.";
RL J. Biol. Chem. 264:9239-9242(1989).
RN [13]
RP X-RAY CRYSTALLOGRAPHY (1.49 ANGSTROMS) OF 22-83, AND DISULFIDE BONDS.
RX PubMed=9757111; DOI=10.1107/s0907444998005125;
RA Nastopoulos V., Kanellopoulos P.N., Tsernoglou D.;
RT "Structure of dimeric and monomeric erabutoxin a refined at 1.5 A
RT resolution.";
RL Acta Crystallogr. D 54:964-974(1998).
RN [14]
RP X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS) OF 22-83, AND DISULFIDE BONDS.
RX PubMed=10691969; DOI=10.1046/j.1432-1327.2000.01099.x;
RA Gaucher J.F., Menez R., Arnoux B., Pusset J., Ducruix A.;
RT "High resolution X-ray analysis of two mutants of a curaremimetic snake
RT toxin.";
RL Eur. J. Biochem. 267:1323-1329(2000).
CC -!- FUNCTION: Binds with high affinity to muscular nicotinic acetylcholine
CC receptors (nAChRs) (tested on Torpedo marmorata, Kd=21 uM) and with low
CC affinity to neuronal alpha-7/CHRNA7 nAChRs (tested on chimeric alpha-
CC 7/CHRNA7, Kd=0.07 nM) and inhibits acetylcholine from binding to the
CC receptor, thereby impairing neuromuscular transmission
CC (PubMed:7721859). Blocks the extracellular increase of dopamine evoked
CC by nicotine at 4.2 uM concentrations (PubMed:9840221). In vivo,
CC produces peripheral paralysis. {ECO:0000269|PubMed:7721859,
CC ECO:0000269|PubMed:9305882, ECO:0000269|PubMed:9840221}.
CC -!- SUBCELLULAR LOCATION: Secreted {ECO:0000269|PubMed:4941832}.
CC -!- TISSUE SPECIFICITY: Expressed by the venom gland. {ECO:0000305}.
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 EMBL; X02533; CAA26373.1; -; mRNA.
DR EMBL; AB017932; BAA75752.1; -; mRNA.
DR EMBL; AB098526; BAC78199.1; -; Genomic_DNA.
DR EMBL; AB098527; BAC78200.1; -; Genomic_DNA.
DR PIR; A01703; N1LT2E.
DR PDB; 1QKD; X-ray; 1.49 A; A/B=22-83.
DR PDB; 1QKE; X-ray; 1.50 A; A=22-83.
DR PDB; 2ERA; X-ray; 1.81 A; A=22-83.
DR PDB; 3ERA; X-ray; 1.70 A; A/B=22-83.
DR PDB; 5EBX; X-ray; 2.00 A; A=22-83.
DR PDBsum; 1QKD; -.
DR PDBsum; 1QKE; -.
DR PDBsum; 2ERA; -.
DR PDBsum; 3ERA; -.
DR PDBsum; 5EBX; -.
DR AlphaFoldDB; P60775; -.
DR BMRB; P60775; -.
DR SMR; P60775; -.
DR EvolutionaryTrace; P60775; -.
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; Signal; Toxin.
FT SIGNAL 1..21
FT /evidence="ECO:0000269|PubMed:4941832"
FT CHAIN 22..83
FT /note="Erabutoxin a"
FT /evidence="ECO:0000269|PubMed:4941832"
FT /id="PRO_0000035446"
FT REGION 24..38
FT /note="Loop I"
FT /evidence="ECO:0000305|PubMed:7721859"
FT REGION 39..44
FT /note="Stretch between loop I and loop II"
FT /evidence="ECO:0000305|PubMed:7721859"
FT REGION 45..62
FT /note="Loop II"
FT /evidence="ECO:0000305|PubMed:7721859"
FT REGION 64..75
FT /note="Loop III"
FT /evidence="ECO:0000305|PubMed:7721859"
FT SITE 27
FT /note="Moderately important residue for binding to
FT acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:7721859"
FT SITE 28
FT /note="Very important residue for binding to acetylcholine
FT receptor"
FT /evidence="ECO:0000269|PubMed:7721859"
FT SITE 29
FT /note="Key residue for binding to acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:7721859,
FT ECO:0000269|PubMed:8419369"
FT SITE 30
FT /note="Moderately important residue for binding to
FT acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:7721859"
FT SITE 31
FT /note="Key residue for binding to acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:7721859,
FT ECO:0000269|PubMed:8419369"
FT SITE 46
FT /note="Moderately important residue for binding to
FT acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:7721859"
FT SITE 48
FT /note="Key residue for binding to acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:8419369"
FT SITE 50
FT /note="Very important residue for binding to acetylcholine
FT receptor"
FT /evidence="ECO:0000269|PubMed:8419369"
FT SITE 52
FT /note="Very important residue for binding to acetylcholine
FT receptor"
FT /evidence="ECO:0000269|PubMed:8419369"
FT SITE 53
FT /note="Moderately important residue for binding to
FT acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:8419369"
FT SITE 54
FT /note="Key residue for binding to acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:7721859,
FT ECO:0000269|PubMed:8419369"
FT SITE 55
FT /note="Moderately important residue for binding to
FT acetylcholine receptor"
FT /evidence="ECO:0000269|PubMed:8419369"
FT SITE 57
FT /note="Very important residue for binding to acetylcholine
FT receptor"
FT /evidence="ECO:0000269|PubMed:7721859"
FT SITE 59
FT /note="Very important residue for binding to acetylcholine
FT receptor"
FT /evidence="ECO:0000269|PubMed:7721859"
FT SITE 68
FT /note="Very important residue for binding to acetylcholine
FT receptor"
FT /evidence="ECO:0000269|PubMed:7721859"
FT DISULFID 24..45
FT /evidence="ECO:0000269|PubMed:10691969,
FT ECO:0000269|PubMed:2722828, ECO:0000269|PubMed:5166329,
FT ECO:0000269|PubMed:9757111, ECO:0000312|PDB:1QKD,
FT ECO:0000312|PDB:1QKE, ECO:0000312|PDB:2ERA,
FT ECO:0000312|PDB:3ERA, ECO:0000312|PDB:5EBX"
FT DISULFID 38..62
FT /evidence="ECO:0000269|PubMed:10691969,
FT ECO:0000269|PubMed:2722828, ECO:0000269|PubMed:5166329,
FT ECO:0000269|PubMed:9757111, ECO:0000312|PDB:1QKD,
FT ECO:0000312|PDB:1QKE, ECO:0000312|PDB:2ERA,
FT ECO:0000312|PDB:3ERA, ECO:0000312|PDB:5EBX"
FT DISULFID 64..75
FT /evidence="ECO:0000269|PubMed:10691969,
FT ECO:0000269|PubMed:2722828, ECO:0000269|PubMed:5166329,
FT ECO:0000269|PubMed:9757111, ECO:0000312|PDB:1QKD,
FT ECO:0000312|PDB:1QKE, ECO:0000312|PDB:2ERA,
FT ECO:0000312|PDB:3ERA, ECO:0000312|PDB:5EBX"
FT DISULFID 76..81
FT /evidence="ECO:0000269|PubMed:10691969,
FT ECO:0000269|PubMed:2722828, ECO:0000269|PubMed:5166329,
FT ECO:0000269|PubMed:9757111, ECO:0000312|PDB:1QKD,
FT ECO:0000312|PDB:1QKE, ECO:0000312|PDB:2ERA,
FT ECO:0000312|PDB:3ERA, ECO:0000312|PDB:5EBX"
FT MUTAGEN 25
FT /note="F->A: 1.2-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 26
FT /note="N->V: 1.4-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 27
FT /note="H->A: 6-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 28
FT /note="Q->L: 23-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 29
FT /note="S->G: 176-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 29
FT /note="S->T: 780-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 30
FT /note="S->G: 8.8-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 31
FT /note="Q->A: 210-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 32
FT /note="P->N: 2.2-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 33
FT /note="Q->A: 1.2-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 34
FT /note="T->V: 3-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 35
FT /note="T->A: 2.7-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 36
FT /note="K->A: No change in potency of inhibition of Torpedo
FT marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 37
FT /note="T->A: 2-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 39
FT /note="Missing: No change in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 42
FT /note="E->A: No change in potency of inhibition of Torpedo
FT marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 46
FT /note="Y->A: 3.7-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 47
FT /note="N->A: No change in potency of inhibition of Torpedo
FT marmorata acetylcholine receptor (identical to erabutoxin
FT b)."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 48
FT /note="K->E: 175-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 49
FT /note="Q->A: 1.35-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 50
FT /note="W->F: 67-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 50
FT /note="W->H: 8.6-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 51
FT /note="S->A: No change in potency of inhibition of Torpedo
FT marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 52
FT /note="D->H: 46-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 52
FT /note="D->N: 1.5-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 53
FT /note="F->L: 7-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 54
FT /note="R->E: 187-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 54
FT /note="R->E: 318-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 54
FT /note="R->K: 25-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 55
FT /note="G->S: 7-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 56
FT /note="T->A: No change in potency of inhibition of Torpedo
FT marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 57
FT /note="I->A: 7-fold increase in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 59
FT /note="E->K: 7.8-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 59
FT /note="E->L: 25-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 59
FT /note="E->Q: 1.4-fold increase in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 65
FT /note="P->V: 3-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 66
FT /note="T->A: No change in potency of inhibition of Torpedo
FT marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 67
FT /note="V->A: 2-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 68
FT /note="K->A: 32-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 69
FT /note="P->Q: No change in potency of inhibition of Torpedo
FT marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 70
FT /note="G->V: 2.4-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 71
FT /note="I->Q: 2.3-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 72
FT /note="K->N: 2-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor (identical to
FT erabutoxin c)."
FT /evidence="ECO:0000269|PubMed:7721859"
FT MUTAGEN 73
FT /note="L->A: 1.4-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:8419369"
FT MUTAGEN 74
FT /note="S->A: 2-fold decrease in potency of inhibition of
FT Torpedo marmorata acetylcholine receptor."
FT /evidence="ECO:0000269|PubMed:7721859"
FT STRAND 23..25
FT /evidence="ECO:0007829|PDB:1QKD"
FT STRAND 35..37
FT /evidence="ECO:0007829|PDB:1QKD"
FT STRAND 45..52
FT /evidence="ECO:0007829|PDB:1QKD"
FT STRAND 55..63
FT /evidence="ECO:0007829|PDB:1QKD"
FT STRAND 72..76
FT /evidence="ECO:0007829|PDB:1QKD"
SQ SEQUENCE 83 AA; 9137 MW; BBB499DA33440F44 CRC64;
MKTLLLTLVV VTIVCLDLGY TRICFNHQSS QPQTTKTCSP GESSCYNKQW SDFRGTIIER
GCGCPTVKPG IKLSCCESEV CNN
