Q8MQL0 (KA163_MESMA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Potassium channel toxin alpha-KTx 16.3 Alternative name(s): Charybdotoxin-like toxin 1 Kchtx1 Short name=KTX1
Organism	Mesobuthus martensii (Manchurian scorpion) (Buthus martensii)
Taxonomic identifier	34649 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Protostomia › Ecdysozoa › Panarthropoda › Arthropoda › Chelicerata › Arachnida › Scorpiones › Buthida › Buthoidea › Buthidae › Mesobuthus

Protein attributes

Sequence length	59 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	Blocks calcium-activated potassium channels.
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 16 subfamily.

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Molecular function	Ion channel impairing toxin Neurotoxin Potassium channel inhibitor Toxin
PTM	Disulfide bond
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 – 22	22	Potential
	Chain	23 – 59	37	Potassium channel toxin alpha-KTx 16.3		PRO_0000035323
Sites
	Site	50	1	Basic residue of the functional dyad By similarity
	Site	59	1	Aromatic residue of the functional dyad By similarity
Amino acid modifications
	Disulfide bond	30 ↔ 51		By similarity
	Disulfide bond	36 ↔ 56		By similarity
	Disulfide bond	40 ↔ 58		By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q8MQL0 [UniParc]. Last modified October 1, 2002. Version 1. Checksum: A1A1A2C400D48C97	FASTA	59	6,483
	10 20 30 40 50 MKIFSILLVA LIICSISICT EAFGLIDVKC FASSECWIAC KKVTGSVQGK CQNNQCRCY

References

[1]	"Cloning and expression of a novel specific blocker of Ca2+ activated K+ from Buthus martensii." Xiao L.-Y., Zhang S.-T., Yu S.-Z., Dong J.-J. Submitted (JUL-2002) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA].

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF520910 mRNA. Translation: AAQ08762.1. AY129234 mRNA. Translation: AAM98736.1.
3D structure databases
ProteinModelPortal	Q8MQL0.
SMR	Q8MQL0. Positions 23-59.
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...

Entry information

Entry name

KA163_MESMA

Accession

Primary (citable) accession number: Q8MQL0

Entry history

Integrated into UniProtKB/Swiss-Prot:	September 26, 2003
Last sequence update:	October 1, 2002
Last modified:	May 1, 2013
This is version 38 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Animal Toxin Annotation Program