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: -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

Keywordsi

Molecular functionBlood 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

Extracellular region or secreted Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi apparatus Nucleus Mitochondrion Manual annotation Automatic computational assertionGraphics by Christian Stolte; Source: COMPARTMENTS

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

Structurei

3D structure databases

SMRiB7S4N9
ModBaseiSearch...
MobiDBiSearch...

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

Keywords - Domaini

Signal

Phylogenomic databases

HOVERGENiHBG006193

Family and domain databases

CDDicd00109 KU, 1 hit
Gene3Di4.10.410.10, 1 hit
InterProiView protein in InterPro
IPR002223 Kunitz_BPTI
IPR036880 Kunitz_BPTI_sf
IPR020901 Prtase_inh_Kunz-CS
PfamiView protein in Pfam
PF00014 Kunitz_BPTI, 1 hit
PRINTSiPR00759 BASICPTASE
SMARTiView protein in SMART
SM00131 KU, 1 hit
SUPFAMiSSF57362 SSF57362, 1 hit
PROSITEiView protein in PROSITE
PS00280 BPTI_KUNITZ_1, 1 hit
PS50279 BPTI_KUNITZ_2, 1 hit

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

Similar proteinsi

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

SMRiB7S4N9
ModBaseiSearch...
MobiDBiSearch...

Protein family/group databases

MEROPSiI02.062

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Phylogenomic databases

HOVERGENiHBG006193

Family and domain databases

CDDicd00109 KU, 1 hit
Gene3Di4.10.410.10, 1 hit
InterProiView protein in InterPro
IPR002223 Kunitz_BPTI
IPR036880 Kunitz_BPTI_sf
IPR020901 Prtase_inh_Kunz-CS
PfamiView protein in Pfam
PF00014 Kunitz_BPTI, 1 hit
PRINTSiPR00759 BASICPTASE
SMARTiView protein in SMART
SM00131 KU, 1 hit
SUPFAMiSSF57362 SSF57362, 1 hit
PROSITEiView protein in PROSITE
PS00280 BPTI_KUNITZ_1, 1 hit
PS50279 BPTI_KUNITZ_2, 1 hit
ProtoNetiSearch...

Entry informationi

Entry nameiVKT_OXYSC
AccessioniPrimary (citable) accession number: B7S4N9
Secondary accession number(s): B5L5M8, B7S4N8, Q7LZE4
Entry historyiIntegrated into UniProtKB/Swiss-Prot: June 16, 2009
Last sequence update: February 10, 2009
Last modified: November 22, 2017
This is version 39 of the entry and version 1 of the sequence. See 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
UniProt is an ELIXIR core data resource
Main funding by: National Institutes of Health

We'd like to inform you that we have updated our Privacy Notice to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.

Do not show this banner again