Reviewed, UniProtKB/Swiss-Prot Q9NII6 (KAX15_MESMA)

Names and origin

Protein names	Recommended name:     Potassium channel toxin alpha-KTx 1.5 Alternative name(s):     BmTX1     Neurotoxin TX1
Organism	Mesobuthus martensii (Manchurian scorpion) (Buthus martensii)
Taxonomic identifier	34649 [NCBI]
Taxonomic lineage	Eukaryota › Metazoa › Arthropoda › Chelicerata › Arachnida › Scorpiones › Buthida › Buthoidea › Buthidae › Mesobuthus

Protein attributes

Sequence length	57 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	Potent blocker of both large-conductance calcium-activated potassium channels (BKCa channels) and voltage-gated potassium channels (Kv1.3).
Subcellular location	Secreted.
Tissue specificity	Expressed by the venom gland.
Sequence similarities	Belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 1 subfamily.

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Molecular function	Ionic channel inhibitor Neurotoxin Potassium channel inhibitor Toxin
PTM	Disulfide bond Pyrrolidone carboxylic acid
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological process	pathogenesis Inferred from electronic annotation. Source: UniProtKB-KW
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 – 20

20

Ref.2

Chain

21 – 57

37

Potassium channel toxin alpha-KTx 1.5

PRO_0000035317

Amino acid modifications

Modified residue

21

1

Pyrrolidone carboxylic acid

Disulfide bond

27 ↔ 48

Ref.3

Disulfide bond

33 ↔ 53

Ref.3

Disulfide bond

37 ↔ 55

Ref.3

Secondary structure

1

.

.

.

.

.

.

.

.

.

57

Helix Strand Turn

Details...

Beta strand

22 – 26

5

Helix

30 – 40

11

Beta strand

47 – 49

3

Beta strand

52 – 54

3

Sequences

	Sequence		Length	Mass (Da)
	Q9NII6-1 [UniParc]. Last modified October 1, 2000. Version 1. Checksum: 78C2184A587BBADB	FASTA	57	6,370
	10 20 30 40 50 MKISFLLLAL VICSIGWSEA QFTDVKCTGS KQCWPVCKQM FGKPNGKCMN GKCRCYS

References

[1]	"Genomic organization of three novel toxins from the scorpion Buthus martensi Karsch that are active on potassium channels." Dai L., Wu J.-J., Gu Y.-H., Lan Z.-D., Ling M.-H., Chi C.-W. Biochem. J. 346:805-809(2000) [PubMed: 10698710] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Purification, characterization, and synthesis of three novel toxins from the Chinese scorpion Buthus martensi, which act on K+ channels." Romi-Lebrun R., Lebrun B., Martin-Eauclaire M.-F., Ishiguro M., Escoubas P., Wu F.Q., Hisada M., Pongs O., Nakajima T. Biochemistry 36:13473-13482(1997) [PubMed: 9354615] [Abstract] Cited for: PROTEIN SEQUENCE OF 21-57, SYNTHESIS, CHARACTERIZATION. Tissue: Venom.
[3]	"Solution structure of two new toxins from the venom of the Chinese scorpion Buthus martensi Karsch blockers of potassium channels." Blanc E., Romi-Lebrun R., Bornet O., Nakajima T., Darbon H. Biochemistry 37:12412-12418(1998) [PubMed: 9730813] [Abstract] Cited for: STRUCTURE BY NMR OF 21-57, DISULFIDE BONDS.

Cross-references

Sequence databases

EMBLGenBankDDBJ

AF208299 Genomic DNA. Translation: AAF63971.1.

3D structure databases

PDBPDBe

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1BIG	NMR	-	A	22-57	[»]

ModBase

Search...

Family and domain databases

InterPro

IPR001947. Scorpion_toxinS.
[Graphical view]

Pfam

PF00451. Toxin_2. 1 hit.
[Graphical view]

PRINTS

PR00286. CHARYBDTOXIN.

ProDom

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

PROSITE

PS01138. SCORP_SHORT_TOXIN. 1 hit.
[Graphical view]

ProtoNet

Search...

Entry information

Entry name

KAX15_MESMA

Accession

Primary (citable) accession number: Q9NII6

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 19, 2001
Last sequence update:	October 1, 2000
Last modified:	June 16, 2009
This is version 59 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

Tox-Prot (Toxin Annotation Project)