P00998 (ISK1_PIG) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Pancreatic secretory trypsin inhibitor

Alternative name(s):
Serine protease inhibitor Kazal-type 1

Gene names

Name:	SPINK1
Synonyms:	PSTI

Organism

Sus scrofa (Pig) [Reference proteome]

Taxonomic identifier

9823 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Laurasiatheria › Cetartiodactyla › Suina › Suidae › Sus

Protein attributes

Sequence length	56 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	This is a trypsin inhibitor, its physiological function is to prevent the trypsin-catalyzed premature activation of zymogens within the pancreas.
Subcellular location	Secreted.
Sequence similarities	Contains 1 Kazal-like domain.

Ontologies

Keywords
Cellular component	Secreted
Molecular function	Protease inhibitor Serine protease inhibitor
PTM	Disulfide bond
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Cellular_component	extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	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 – 56

56

Pancreatic secretory trypsin inhibitor

PRO_0000073027

Regions

Domain

3 – 56

54

Kazal-like

Sites

Site

18 – 19

2

Reactive bond

Amino acid modifications

Disulfide bond

9 ↔ 38

Ref.3

Disulfide bond

16 ↔ 35

Ref.3

Disulfide bond

24 ↔ 56

Ref.3

Natural variations

Natural variant

1 – 4

4

Missing in a second inhibitor.

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

56

Helix Strand Turn

Details...

Beta strand

12 – 17

6

Beta strand

23 – 25

3

Beta strand

30 – 33

4

Helix

34 – 42

9

Beta strand

50 – 54

5

Sequences

	Sequence		Length	Mass (Da)
	P00998 [UniParc]. Last modified July 21, 1986. Version 1. Checksum: 39A3649DADF16D25	FASTA	56	6,023
	10 20 30 40 50 TSPQREATCT SEVSGCPKIY NPVCGTDGIT YSNECVLCSE NKKRQTPVLI QKSGPC

References

[1]	"The structure of the porcine pancreatic secretory trypsin inhibitor. I. A sequence determination by Edman degradation and mass spectral identification of the p-bromophenyl-thiohydantoins." Tschesche H., Wachter E. Eur. J. Biochem. 16:187-198(1970) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE.
[2]	"The primary structure of the porcine pancreatic secretory trypsin inhibitor. I. Amino acid sequence of the reduced S-aminoethylated protein." Bartelt D.C., Greene L.J. J. Biol. Chem. 246:2218-2229(1971) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE.
[3]	"Disulfide bridges of the secretory trypsin inhibitor from procine pancreas and the degradation of covalent structure during the temporary inhibition." Tschesche H., Schneider M., Reidel G., Klein H. Hoppe-Seyler's Z. Physiol. Chem. 353:763-764(1972) [PubMed] [Europe PMC] [Abstract] Cited for: DISULFIDE BONDS.
[4]	"Trypsin inhibitors. VII. Primary structure of the specific trypsin inhibitor II (Kazal-type) from porcine pancreas. Sequence analysis with mass spectrometry identification of the p-bromophenylthio-hydantoins from the Edman degradation." Tschesche H., Wachter E. Hoppe-Seyler's Z. Physiol. Chem. 351:1449-1459(1970) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF A SECOND INHIBITOR.
[5]	"Three-dimensional structure of the complex between pancreatic secretory trypsin inhibitor (Kazal type) and trypsinogen at 1.8-A resolution. Structure solution, crystallographic refinement and preliminary structural interpretation." Bolognesi M., Gatti G., Menegatti E., Guarneri M., Marquart M., Papamokos E., Huber R. J. Mol. Biol. 162:839-868(1982) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS).

Cross-references

Sequence databases

PIR

TIPG. A91174.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1TGS	X-ray	1.80	I	1-56	[»]

ProteinModelPortal

P00998.

SMR

P00998. Positions 1-56.

ModBase

Search...

Protein family/group databases

MEROPS

I01.011.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

Ensembl

ENSSSCT00000026654; ENSSSCP00000022179; ENSSSCG00000027244.

Phylogenomic databases

GeneTree

ENSGT00530000064228.

HOVERGEN

HBG006182.

OMA

IYNPVCG.

Family and domain databases

InterPro

IPR002350. Kazal_dom.
IPR001239. Prot_inh_Kazal-m.
[Graphical view]

Pfam

PF00050. Kazal_1. 1 hit.
[Graphical view]

PRINTS

PR00290. KAZALINHBTR.

SMART

SM00280. KAZAL. 1 hit.
[Graphical view]

PROSITE

PS00282. KAZAL_1. 1 hit.
PS51465. KAZAL_2. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

EvolutionaryTrace

P00998.

Entry information

Entry name

ISK1_PIG

Accession

Primary (citable) accession number: P00998

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	July 21, 1986
Last modified:	May 1, 2013
This is version 86 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program