P00980 (IVBII_DENAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Protease inhibitor 1 homolog Alternative name(s): Alpha-dendrotoxin Short name=Alpha-DTX Toxin C13S2C3 Venom basic protease inhibitor 1 homolog
Organism	Dendroaspis angusticeps (Eastern green mamba) (Naja angusticeps)
Taxonomic identifier	8618 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Sauropsida › Sauria › Lepidosauria › Squamata › Scleroglossa › Serpentes › Colubroidea › Elapidae › Elapinae › Dendroaspis

Protein attributes

Sequence length	59 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	This protease inhibitor homolog has very low toxicity. It blocks voltage-gated potassium channels and facilitate neurotransmitter release.
Subcellular location	Secreted.
Tissue specificity	Expressed by the venom gland.
Toxic dose	LD50 is 23 mg/kg by intravenous injection.
Sequence similarities	Belongs to the venom Kunitz-type family. Contains 1 BPTI/Kunitz inhibitor domain.

Ontologies

Keywords
Cellular component	Secreted
Molecular function	Ion channel impairing toxin Neurotoxin Potassium channel inhibitor Protease inhibitor Serine protease inhibitor Toxin
PTM	Disulfide bond Pyrrolidone carboxylic acid
Technical term	3D-structure 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 serine-type endopeptidase 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

Chain

1 – 59

59

Protease inhibitor 1 homolog

PRO_0000155433

Regions

Domain

7 – 57

51

BPTI/Kunitz inhibitor

Sites

Site

17 – 18

2

Reactive bond

Amino acid modifications

Modified residue

1

1

Pyrrolidone carboxylic acid Ref.1

Disulfide bond

7 ↔ 57

Ref.1

Disulfide bond

16 ↔ 40

Ref.1

Disulfide bond

32 ↔ 53

Ref.1

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

59

Helix Strand Turn

Details...

Helix

5 – 8

4

Beta strand

15 – 17

3

Beta strand

20 – 26

7

Turn

27 – 30

4

Beta strand

31 – 37

7

Beta strand

47 – 49

3

Helix

50 – 57

8

Sequences

	Sequence		Length	Mass (Da)
	P00980 [UniParc]. Last modified July 21, 1986. Version 1. Checksum: 96B60752E8AD81AE	FASTA	59	7,071
	10 20 30 40 50 QPRRKLCILH RNPGRCYDKI PAFYYNQKKK QCERFDWSGC GGNSNRFKTI EECRRTCIG

References

[1]	"Snake venoms. The amino acid sequences of two proteinase inhibitor homologues from Dendroaspis angusticeps venom." Joubert F.J., Taljaard N. Hoppe-Seyler's Z. Physiol. Chem. 361:661-674(1980) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE. Tissue: Venom.
[2]	"Crystal structure of alpha-dendrotoxin from the green mamba venom and its comparison with the structure of bovine pancreatic trypsin inhibitor." Skarzynski T. J. Mol. Biol. 224:671-683(1992) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).

Cross-references

Sequence databases

PIR

VIEPIA. A01212.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1DTX	X-ray	2.20	A	2-59	[»]

ProteinModelPortal

P00980.

SMR

P00980. Positions 1-59.

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Phylogenomic databases

HOVERGEN

HBG006193.

Family and domain databases

Gene3D

4.10.410.10. 1 hit.

InterPro

IPR002223. Prot_inh_Kunz-m.
IPR020901. Prtase_inh_Kunz-CS.
[Graphical view]

Pfam

PF00014. Kunitz_BPTI. 1 hit.
[Graphical view]

PRINTS

PR00759. BASICPTASE.

SMART

SM00131. KU. 1 hit.
[Graphical view]

SUPFAM

SSF57362. Prot_inh_Kunz-m. 1 hit.

PROSITE

PS00280. BPTI_KUNITZ_1. 1 hit.
PS50279. BPTI_KUNITZ_2. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

EvolutionaryTrace

P00980.

Entry information

Entry name

IVBII_DENAN

Accession

Primary (citable) accession number: P00980

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	July 21, 1986
Last modified:	April 3, 2013
This is version 88 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program

Annotation program

Animal Toxin Annotation Program