P69940 (KBX1_TITSE) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Potassium channel toxin TsTXK-beta Alternative name(s): Potassium channel toxin beta-KTx 1 TSK2 Tityustoxin K-beta Short name=TsTX K beta Short name=TsTX-K beta Short name=TsTXKbeta
Organism	Tityus serrulatus (Brazilian scorpion)
Taxonomic identifier	6887 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Protostomia › Ecdysozoa › Panarthropoda › Arthropoda › Chelicerata › Arachnida › Scorpiones › Buthida › Buthoidea › Buthidae › Tityus

Protein attributes

Sequence length	87 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	Selectively blocks voltage-gated noninactivating potassium channels in synaptosomes. Ref.4
Subcellular location	Secreted Ref.3.
Tissue specificity	Expressed by the venom gland. Ref.3
Miscellaneous	It is not known if the sequenced fragment corresponding to the propeptide is the result of the post-translational maturation process, or if it has a biological activity of its own (Ref.3).
Sequence similarities	Belongs to the long chain scorpion toxin family. Class 1 subfamily.
Mass spectrometry	Molecular mass is 6716.15 Da from positions 26 - 85. Determined by ESI. Ref.2

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Molecular function	Ion channel impairing toxin Neurotoxin Potassium channel inhibitor Toxin
PTM	Disulfide bond
Technical term	Direct protein sequencing
Gene Ontology (GO)
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 – 19	19	Potential
	Propeptide	20 – 27	8	Probable		PRO_0000035342
	Chain	28 – 87	60	Potassium channel toxin TsTXK-beta		PRO_0000035343
Amino acid modifications
	Disulfide bond	56 ↔ 77		By similarity
	Disulfide bond	63 ↔ 82		By similarity
	Disulfide bond	67 ↔ 84		By similarity

Sequences

	Sequence		Length	Mass (Da)
	P69940 [UniParc]. Last modified November 13, 2007. Version 2. Checksum: ADCA961D54841F62	FASTA	87	9,729
	10 20 30 40 50 60 MERKLALLLI LGMVTLASCG LREKHVQKLV ALIPNDQLRS ILKAVVHKVA KTQFGCPAYE 70 80 GYCNDHCNDI ERKDGECHGF KCKCAKD

References

[1]	"Screening of expression libraries using ELISA: identification of immunogenic proteins from Tityus bahiensis and Tityus serrulatus venom." Kalapothakis E., Jardim S., Magalhaes A.C., Mendes T.M., De Marco L., Afonso L.C.C., Chavez-Olortegui C. Toxicon 39:679-685(2001) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Venom gland.
[2]	"Evidence for a new class of scorpion toxins active against K+ channels." Legros C., Ceard B., Bougis P.E., Martin-Eauclaire M.-F. FEBS Lett. 431:375-380(1998) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 3-87, MASS SPECTROMETRY. Tissue: Venom gland.
[3]	"Tityus serrulatus venom peptidomics: assessing venom peptide diversity." Rates B., Ferraz K.K., Borges M.H., Richardson M., De Lima M.E., Pimenta A.M. Toxicon 52:611-618(2008) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 20-47, SUBCELLULAR LOCATION, TISSUE SPECIFICITY. Tissue: Venom.
[4]	"Tityustoxin K alpha blocks voltage-gated noninactivating K+ channels and unblocks inactivating K+ channels blocked by alpha-dendrotoxin in synaptosomes." Rogowski R.S., Krueger B.K., Collins J.H., Blaustein M.P. Proc. Natl. Acad. Sci. U.S.A. 91:1475-1479(1994) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 28-72, FUNCTION. Tissue: Venom.
[5]	Erratum Rogowski R.S., Krueger B.K., Collins J.H., Blaustein M.P. Proc. Natl. Acad. Sci. U.S.A. 93:12051-12051(1996)

Cross-references

3D structure databases
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
ProtoNet	Search...

Entry information

Entry name

KBX1_TITSE

Accession

Primary (citable) accession number: P69940

Entry history

Integrated into UniProtKB/Swiss-Prot:	January 4, 2005
Last sequence update:	November 13, 2007
Last modified:	April 3, 2013
This is version 29 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Animal Toxin Annotation Program