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Peptide record

TPDB72687

Neurotoxin standard
72 amino acids
Basic Information
3D PDB MODEL
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TPDB72687
Neurotoxin
Toxicity and safety peptides
NTxPred2
standard
No
A 72-aa standard natural neurotoxin peptide sequence curated from NTxPred2, with an available 3D structural model.
Sequence
MKLLPLLFVILIVCAILPDEASCDQSELERKEENFKDESREIVKRSCKKECSGSRRTKKCMQKCNREHGHGR
Physicochemical Analysis
C354H598N110O108S8
WY
EK
8379.79
8.58
18
12
20
+4
32.77
-0.746
74.44
Mammalian: 30 hour Yeast: >20 hour E.coli: >10 hour
375
4.48
17
Residue Composition
number
2
A
7
R
2
N
3
D
6
C
9
E
2
Q
3
G
2
H
4
I
7
L
9
K
2
M
2
F
2
P
6
S
1
T
0
W
0
Y
3
V
Amino Acid Distribution
A: 2 R: 7 N: 2 D: 3 C: 6 E: 9 Q: 2 G: 3 H: 2 I: 4 L: 7 K: 9 M: 2 F: 2 P: 2 S: 6 T: 1 W: 0 Y: 0 V: 3
Chemical Descriptors
72
C354H598N110O108S8
8379.79
8.58
+4
32.77
-0.746
Evidence Records 1 records
Evidence 1 Activity

Activity

Neurotoxin
FUNCTION: Weak blocker of potassium channels Kv1.1/KCNA1 (IC(50)=578.5 nM-9.9 uM) and Kv1.6/KCNA6 (~60% block at 30 uM of toxin) (PubMed:22305749, PubMed:26724500). Acts by binding to the pore and occluding it (PubMed:22305749). Has a voltage-dependent mode of action, which can be explained by a high content of basic residues causing repulsions at higher membrane voltages (PubMed:22305749). Shows a weak interaction with muscle-type nicotinic acetylcholine receptors (nAChR), since it inhibits alpha-bungarotoxin binding to muscle-type nAChR from T.californica (IC(50)=1.4 uM) (PubMed:31276191). This suggests it probably weakly inhibits muscle nAChR (PubMed:31276191). The mode of binding to potassium channels of this toxin differs from its homologs (including HefuTx1), since it lacks the key aromatic residue of the functional dyad. In contrast, its functionally important site is composed of a number of basic residues (PubMed:32172732). {ECO:0000269|PubMed:22305749, ECO:0000269|PubMed:31276191, ECO:0000269|PubMed:32172732}.

Target

nicotinic acetylcholine receptor (nAChR) acetylcholine receptor voltage-gated potassium channel (Kv) proton-gated sodium channel / ASIC

Source & Reference

NA
UniProtKB/Swiss-Prot Tox-Prot

Other

Heterometrus laoticus (Thai giant scorpion)
Neurotoxin Postsynaptic neurotoxin Acetylcholine receptor inhibiting toxin Ion channel impairing toxin Potassium channel impairing toxin Voltage-gated potassium channel impairing toxin
Weak blocker of potassium channels Kv1.1/KCNA1 (IC(50)=578.5 nM-9.9 uM) and Kv1.6/KCNA6 (~60% block at 30 uM of toxin) (PubMed:22305749, PubMed:26724500). Acts by binding to the pore and occluding it (PubMed:22305749).
Potassium channel toxin kappa-KTx 5.1 (HelaTx1)
scorpion
Short scorpion toxin superfamily, Potassium channel inhibitor kappa-KTx family, Kappa-KTx 5 subfamily
Evidence at protein level
3D-structure Acetylcholine receptor inhibiting toxin Amidation Cleavage on pair of basic residues Direct protein sequencing Disulfide bond Ion channel impairing toxin Neurotoxin Postsynaptic neurotoxin Potassium channel impairing toxin Secreted Signal Toxin Voltage-gated potassium channel impairing toxin
TISSUE SPECIFICITY: Expressed by the venom gland. {ECO:0000305|PubMed:22305749}.
Additional Detail Fields 7 fields
3D-structure Acetylcholine receptor inhibiting toxin Amidation Cleavage on pair of basic residues Direct protein sequencing Disulfide bond Ion channel impairing toxin Neurotoxin Postsynaptic neurotoxin Potassium channel impairing toxin Secreted Signal Toxin Voltage-gated potassium channel impairing toxin
Neurotoxin Postsynaptic neurotoxin Acetylcholine receptor inhibiting toxin Ion channel impairing toxin Potassium channel impairing toxin Voltage-gated potassium channel impairing toxin
Evidence at protein level
Short scorpion toxin superfamily, Potassium channel inhibitor kappa-KTx family, Kappa-KTx 5 subfamily
Potassium channel toxin kappa-KTx 5.1 (HelaTx1)
TISSUE SPECIFICITY: Expressed by the venom gland. {ECO:0000305|PubMed:22305749}.
scorpion