Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Kunitz-type serine protease inhibitor taicotoxin

Gene
N/A
Organism
Oxyuranus scutellatus scutellatus (Australian taipan) (Coastal taipan)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Heterotrimer: blocks the voltage-dependent L-type calcium channels (Cav) from the heart, and the small conductance calcium-activated potassium channels (KCa) in the chromaffin cells and in the brain. Is very toxic to mice.
Monomer: serine protease inhibitor that inhibits plasma kallikrein (Ki=0.057 nM), tissue kallikrein (Ki=0.23 nM), trypsin (Ki=0.31 nM), plasmin (Ki=6.1 nM), elastase (Ki=201 nM), factor Xa (Ki=871 nM), alpha-factor XIIa (Ki=2380 nM). Does not inhibit APC, urokinase-type plasminogen activator (uPA/PLAU), tissue plasminogen activator (tPA/PLAT), thrombin and factor VIIa. In addition, the monomer inhibits fibrinolysis in whole blood and prolonged the intrinsec clotting time.

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sitei41 – 42Reactive bond for trypsinBy similarity2

GO - Molecular functioni

Complete GO annotation...

Keywords - Molecular functioni

Blood coagulation cascade inhibiting toxin, Calcium channel impairing toxin, Calcium-activated potassium channel impairing toxin, Hemostasis impairing toxin, Ion channel impairing toxin, Neurotoxin, Potassium channel impairing toxin, Protease inhibitor, Serine protease inhibitor, Toxin, Voltage-gated calcium channel impairing toxin

Protein family/group databases

MEROPSiI02.062.

Names & Taxonomyi

Protein namesi
Recommended name:
Kunitz-type serine protease inhibitor taicotoxin
Alternative name(s):
Taicatoxin, serine protease inhibitor component
Short name:
TCX
Short name:
TSPI
Venom protease inhibitor 1
Venom protease inhibitor 2
OrganismiOxyuranus scutellatus scutellatus (Australian taipan) (Coastal taipan)
Taxonomic identifieri8667 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiLepidosauriaSquamataBifurcataUnidentataEpisquamataToxicoferaSerpentesColubroideaElapidaeAcanthophiinaeOxyuranus

Subcellular locationi

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Secreted

Pathology & Biotechi

Toxic dosei

LD50 of the heterotrimer is 50-100 µg/kg to mice.1 Publication

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Signal peptidei1 – 242 PublicationsAdd BLAST24
ChainiPRO_000015544325 – 86Kunitz-type serine protease inhibitor taicotoxinAdd BLAST62
PropeptideiPRO_000037692987 – 882

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Disulfide bondi31 ↔ 81PROSITE-ProRule annotation
Disulfide bondi40 ↔ 64PROSITE-ProRule annotation
Disulfide bondi56 ↔ 77PROSITE-ProRule annotation

Keywords - PTMi

Disulfide bond

Expressioni

Tissue specificityi

Expressed by the venom gland.1 Publication

Interactioni

Subunit structurei

Heterotrimer composed of an alpha-neurotoxin-like peptide of 8 kDa (AC P0CJ35), a neurotoxic phospholipase of 16 kDa (AC Q7LZG2) and this serine protease inhibitor of 7 kDa at an approximate stoichiometry of 1:1:4; non-covalently linked.1 Publication

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini31 – 81BPTI/Kunitz inhibitorPROSITE-ProRule annotationAdd BLAST51

Sequence similaritiesi

Belongs to the venom Kunitz-type family.Curated
Contains 1 BPTI/Kunitz inhibitor domain.PROSITE-ProRule annotation

Keywords - Domaini

Signal

Phylogenomic databases

HOVERGENiHBG006193.

Family and domain databases

Gene3Di4.10.410.10. 1 hit.
InterProiIPR002223. Kunitz_BPTI.
IPR020901. Prtase_inh_Kunz-CS.
[Graphical view]
PfamiPF00014. Kunitz_BPTI. 1 hit.
[Graphical view]
PRINTSiPR00759. BASICPTASE.
SMARTiSM00131. KU. 1 hit.
[Graphical view]
SUPFAMiSSF57362. SSF57362. 1 hit.
PROSITEiPS00280. BPTI_KUNITZ_1. 1 hit.
PS50279. BPTI_KUNITZ_2. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

B7S4N9-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MSSGGLLLLL GLLTLWEVLT PVSSKDRPKF CHLPPKPGPC RAAIPRFYYN
60 70 80
PHSKQCEKFI YGGCHGNANS FKTPDECNYT CLGVSLPK
Length:88
Mass (Da):9,711
Last modified:February 10, 2009 - v1
Checksum:iBA22F6D73E1D6F38
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti17 – 18EV → AE in ACC77765 (PubMed:18979207).Curated2
Sequence conflicti24 – 25SK → GQ in ACC77765 (PubMed:18979207).Curated2
Sequence conflicti25K → Q in ACC77765 (PubMed:18979207).Curated1
Sequence conflicti36K → N in ACC77765 (PubMed:18979207).Curated1
Sequence conflicti36K → N in ABO31437 (Ref. 1) Curated1
Sequence conflicti70S → K AA sequence (PubMed:1485334).Curated1

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
EF112394 mRNA. Translation: ABO31438.1.
EF112393 mRNA. Translation: ABO31437.1.
EU401816 Genomic DNA. Translation: ACC77765.1.
PIRiA44180.

Cross-referencesi

Web resourcesi

Wikipedia

Taicatoxin entry

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
EF112394 mRNA. Translation: ABO31438.1.
EF112393 mRNA. Translation: ABO31437.1.
EU401816 Genomic DNA. Translation: ACC77765.1.
PIRiA44180.

3D structure databases

ModBaseiSearch...
MobiDBiSearch...

Protein family/group databases

MEROPSiI02.062.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Phylogenomic databases

HOVERGENiHBG006193.

Family and domain databases

Gene3Di4.10.410.10. 1 hit.
InterProiIPR002223. Kunitz_BPTI.
IPR020901. Prtase_inh_Kunz-CS.
[Graphical view]
PfamiPF00014. Kunitz_BPTI. 1 hit.
[Graphical view]
PRINTSiPR00759. BASICPTASE.
SMARTiSM00131. KU. 1 hit.
[Graphical view]
SUPFAMiSSF57362. SSF57362. 1 hit.
PROSITEiPS00280. BPTI_KUNITZ_1. 1 hit.
PS50279. BPTI_KUNITZ_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiVKT_OXYSC
AccessioniPrimary (citable) accession number: B7S4N9
Secondary accession number(s): B5L5M8, B7S4N8, Q7LZE4
Entry historyi
Integrated into UniProtKB/Swiss-Prot: June 16, 2009
Last sequence update: February 10, 2009
Last modified: October 14, 2015
This is version 34 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
Annotation programAnimal Toxin Annotation Program

Miscellaneousi

Keywords - Technical termi

Direct protein sequencing

Documents

  1. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.