P0C194 (KAX6B_OPIMA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Potassium channel toxin alpha-KTx 6.11 Alternative name(s): Male-specific potassium channel inhibitor IsTX
Organism	Opisthacanthus madagascariensis (Scorpion)
Taxonomic identifier	167108 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Protostomia › Ecdysozoa › Panarthropoda › Arthropoda › Chelicerata › Arachnida › Scorpiones › Iurida › Scorpionoidea › Hemiscorpiidae › Liochelinae › Opisthacanthus

Protein attributes

Sequence length	63 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Blocks voltage-gated potassium channels Kv1.1/KCNA1 and Kv1.3/KCNA3. Causes paralysis to crickets.
Subcellular location	Secreted.
Tissue specificity	Expressed by the venom gland. Only expressed by males.
Domain	Has the structural arrangement of an alpha-helix connected to a beta-sheet by disulfide bonds (CSalpha/beta).
Sequence similarities	Belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 6 subfamily.
Mass spectrometry	Molecular mass is 4818.23 Da from positions 22 - 62. Determined by MALDI. Ref.1

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Molecular function	Ion channel impairing toxin Neurotoxin Potassium channel inhibitor Toxin
PTM	Disulfide bond
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological_process	pathogenesis Inferred from electronic annotation. Source: InterPro
Cellular_component	extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	potassium channel inhibitor activity Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 21

21

Ref.1

Chain

22 – 62

41

Potassium channel toxin alpha-KTx 6.11

PRO_0000232654

Sites

Site

48

1

Basic residue of the functional dyad By similarity

Site

50

1

Important for activity By similarity

Site

51

1

Important for activity By similarity

Site

57

1

Aromatic residue of the functional dyad By similarity

Amino acid modifications

Disulfide bond

28 ↔ 49

Ref.1

Disulfide bond

34 ↔ 54

Ref.1

Disulfide bond

38 ↔ 56

Ref.1

Disulfide bond

44 ↔ 60

Ref.1

Secondary structure

1

.

.

.

.

.

.

.

63

Helix Strand Turn

Details...

Helix

31 – 40

10

Beta strand

48 – 50

3

Beta strand

53 – 55

3

Sequences

	Sequence		Length	Mass (Da)
	P0C194 [UniParc]. Last modified April 18, 2006. Version 1. Checksum: C9BDC4E26532BB26	FASTA	63	7,324
	10 20 30 40 50 60 MKVAYLLVLF TIMMLANDAS LVHTNIPCRG TSDCYEPCEK KYNCARAKCM NRHCNCYNNC PWR

References

[1]

"Solution structure of IsTX. A male scorpion toxin from Opisthacanthus madagascariensis (Ischnuridae)." Yamaji N., Dai L., Sugase K., Andriantsiferana M., Nakajima T., Iwashita T. Eur. J. Biochem. 271:3855-3864(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 22-62, DISULFIDE BONDS, SYNTHESIS OF 22-62, MASS SPECTROMETRY, STRUCTURE BY NMR OF 22-62. Tissue: Venom and Venom gland.

Cross-references

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1WMT	NMR	-	A	22-62	[»]

ProteinModelPortal

P0C194.

SMR

P0C194. Positions 23-62.

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Family and domain databases

Gene3D

3.30.30.10. 1 hit.

InterPro

IPR003614. Scorpion_toxin-like.
IPR001947. Scorpion_toxinS_K_inh.
[Graphical view]

Pfam

PF00451. Toxin_2. 1 hit.
[Graphical view]

ProDom

PD003586. Scorpion_toxinS. 1 hit.
[Graphical view] [Entries sharing at least one domain]

SUPFAM

SSF57095. SSF57095. 1 hit.

PROSITE

PS01138. SCORP_SHORT_TOXIN. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

EvolutionaryTrace

P0C194.

Entry information

Entry name

KAX6B_OPIMA

Accession

Primary (citable) accession number: P0C194

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 18, 2006
Last sequence update:	April 18, 2006
Last modified:	May 1, 2013
This is version 29 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Animal Toxin Annotation Program