Q4GWU5 (SFTI1_HELAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Trypsin inhibitor 1

Alternative name(s):
SFTI-1

Gene names

Name:

sfti1

Organism

Helianthus annuus (Common sunflower)

Taxonomic identifier

4232 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Viridiplantae › Streptophyta › Streptophytina › Embryophyta › Tracheophyta › Euphyllophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › campanulids › Asterales › Asteraceae › Asteroideae › Heliantheae alliance › Heliantheae › Helianthus

Protein attributes

Sequence length	56 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	Inhibits trypsin, cathepsin G, elastase, chymotrypsin and thrombin. Does not inhibit factor Xa. Ref.2
Post-translational modification	This is a cyclic peptide. Ref.2
Mass spectrometry	Molecular mass is 1513 Da from positions 40 - 53. Determined by ESI. Ref.2

Ontologies

Keywords
Domain	Signal
Molecular function	Protease inhibitor Serine protease inhibitor
PTM	Disulfide bond
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Molecular_function	serine-type endopeptidase inhibitor activity Inferred from direct assay Ref.2. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 25

25

Potential

Propeptide

26 – 39

14

Ref.2

PRO_0000042672

Peptide

40 – 53

14

Trypsin inhibitor 1 Ref.2

PRO_0000042673

Propeptide

54 – 56

3

PRO_0000042674

Sites

Site

44 – 45

2

Reactive bond By similarity UniProtKB P81705

Amino acid modifications

Disulfide bond

42 ↔ 50

Ref.2 Ref.4

Cross-link

40 ↔ 53

Cyclopeptide (Gly-Asp)

Secondary structure

1

.

.

.

.

.

.

.

.

56

Helix Strand Turn

Details...

Beta strand

34 – 36

3

Beta strand

41 – 43

3

Beta strand

44 – 47

4

Beta strand

49 – 52

4

Sequences

	Sequence		Length	Mass (Da)
	Q4GWU5 [UniParc]. Last modified August 30, 2005. Version 1. Checksum: BF3BAF97C25F19A7	FASTA	56	5,971
	10 20 30 40 50 MATTMAKLIT LVVLAILAFV EVSVSGYKTS ISTITIEDNG RCTKSIPPIC FPDGRP

References

[1]	"Discovery, structural determination, and putative processing of the precursor protein that produces the cyclic trypsin inhibitor sunflower trypsin inhibitor 1." Mulvenna J.P., Foley F.M., Craik D.J. J. Biol. Chem. 280:32245-32253(2005) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], STRUCTURE BY NMR OF 26-56. Tissue: Leaf.
[2]	"High-resolution structure of a potent, cyclic proteinase inhibitor from sunflower seeds." Luckett S., Garcia R.S., Barker J.J., Konarev A.V., Shewry P.R., Clarke A.R., Brady R.L. J. Mol. Biol. 290:525-533(1999) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 40-53, CROSS-LINK, FUNCTION, MASS SPECTROMETRY, STRUCTURE BY NMR OF 40-53. Tissue: Seed.
[3]	"Solution structures by 1H NMR of the novel cyclic trypsin inhibitor SFTI-1 from sunflower seeds and an acyclic permutant." Korsinczky M.L., Schirra H.J., Rosengren K.J., West J., Condie B.A., Otvos L., Anderson M.A., Craik D.J. J. Mol. Biol. 311:579-591(2001) [PubMed] [Europe PMC] [Abstract] Cited for: STRUCTURE BY NMR OF 40-53.
[4]	"Enzymatic cyclization of a potent bowman-birk protease inhibitor, sunflower trypsin inhibitor-1, and solution structure of an acyclic precursor peptide." Marx U.C., Korsinczky M.L.J., Schirra H.J., Jones A., Condie B., Otvos L. Jr., Craik D.J. J. Biol. Chem. 278:21782-21789(2003) [PubMed] [Europe PMC] [Abstract] Cited for: STRUCTURE BY NMR OF 40-53, DISULFIDE BOND.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

AM050587 Genomic DNA. Translation: CAJ19097.1.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1JBL	NMR	-	A	40-53	[»]
1JBN	NMR	-	A	40-53	[»]
1O8Y	NMR	-	A	40-53	[»]
1O8Z	NMR	-	A	40-53	[»]
1SFI	X-ray	1.65	I	40-53	[»]
1T9E	NMR	-	A	40-53	[»]
2AB9	NMR	-	A	26-56	[»]
3P8F	X-ray	2.00	I	40-53	[»]
4ABI	X-ray	1.55	B	40-46	[»]
4ABJ	X-ray	1.45	B	40-45	[»]

ProteinModelPortal

Q4GWU5.

SMR

Q4GWU5. Positions 26-56.

ModBase

Search...

Protein family/group databases

MEROPS

I12.002.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Family and domain databases

ProtoNet

Search...

Other

EvolutionaryTrace

Q4GWU5.

Entry information

Entry name

SFTI1_HELAN

Accession

Primary (citable) accession number: Q4GWU5

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 25, 2005
Last sequence update:	August 30, 2005
Last modified:	July 11, 2012
This is version 29 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program