ID   ITR1_CUCMA              Reviewed;          29 AA.
AC   P01074;
DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT   21-JUL-1986, sequence version 1.
DT   25-MAY-2022, entry version 117.
DE   RecName: Full=Trypsin inhibitor 1;
DE   AltName: Full=CMTI-I;
DE   AltName: Full=ITD-I;
DE   AltName: Full=Trypsin inhibitor I;
OS   Cucurbita maxima (Pumpkin) (Winter squash).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC   rosids; fabids; Cucurbitales; Cucurbitaceae; Cucurbiteae; Cucurbita.
OX   NCBI_TaxID=3661;
RN   [1]
RP   PROTEIN SEQUENCE.
RC   TISSUE=Seed;
RX   PubMed=6840699; DOI=10.1515/bchm2.1983.364.1.93;
RA   Wilusz T., Wieczorek M., Polanowski A., Denton A., Cook J.,
RA   Laskowski M. Jr.;
RT   "Amino-acid sequence of two trypsin isoinhibitors, ITD I and ITD III from
RT   squash seeds (Cucurbita maxima).";
RL   Hoppe-Seyler's Z. Physiol. Chem. 364:93-95(1983).
RN   [2]
RP   X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
RX   PubMed=2914611; DOI=10.1016/0014-5793(89)80486-7;
RA   Bode W., Greyling H.J., Huber R., Otlewski J., Wilusz T.;
RT   "The refined 2.0 A X-ray crystal structure of the complex formed between
RT   bovine beta-trypsin and CMTI-I, a trypsin inhibitor from squash seeds
RT   (Cucurbita maxima). Topological similarity of the squash seed inhibitors
RT   with the carboxypeptidase A inhibitor from potatoes.";
RL   FEBS Lett. 242:285-292(1989).
RN   [3]
RP   STRUCTURE BY NMR.
RX   PubMed=2614837; DOI=10.1016/0022-2836(89)90137-x;
RA   Holak T.A., Gondol D., Otlewski J., Wilusz T.;
RT   "Determination of the complete three-dimensional structure of the trypsin
RT   inhibitor from squash seeds in aqueous solution by nuclear magnetic
RT   resonance and a combination of distance geometry and dynamical simulated
RT   annealing.";
RL   J. Mol. Biol. 210:635-648(1989).
RN   [4]
RP   STRUCTURE BY NMR.
RX   PubMed=10716179; DOI=10.1110/ps.9.2.273;
RA   Zhukov I., Jaroszewski L., Bierzynski A.;
RT   "Conservative mutation Met8 --> Leu affects the folding process and
RT   structural stability of squash trypsin inhibitor CMTI-I.";
RL   Protein Sci. 9:273-279(2000).
CC   -!- FUNCTION: Inhibits trypsin.
CC   -!- SUBCELLULAR LOCATION: Secreted.
CC   -!- DOMAIN: The presence of a 'disulfide through disulfide knot'
CC       structurally defines this protein as a knottin.
CC   -!- SIMILARITY: Belongs to the protease inhibitor I7 (squash-type serine
CC       protease inhibitor) family. {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   PIR; A01313; TIPU.
DR   PDB; 1CTI; NMR; -; A=1-29.
DR   PDB; 1LU0; X-ray; 1.03 A; A/B=1-29.
DR   PDB; 1PPE; X-ray; 2.00 A; I=1-29.
DR   PDB; 2CTI; NMR; -; A=1-29.
DR   PDB; 2STA; X-ray; 1.80 A; I=1-29.
DR   PDB; 2V1V; NMR; -; A=1-29.
DR   PDB; 3CTI; NMR; -; A=1-29.
DR   PDBsum; 1CTI; -.
DR   PDBsum; 1LU0; -.
DR   PDBsum; 1PPE; -.
DR   PDBsum; 2CTI; -.
DR   PDBsum; 2STA; -.
DR   PDBsum; 2V1V; -.
DR   PDBsum; 3CTI; -.
DR   AlphaFoldDB; P01074; -.
DR   SMR; P01074; -.
DR   MINT; P01074; -.
DR   MEROPS; I07.005; -.
DR   EvolutionaryTrace; P01074; -.
DR   Proteomes; UP000504608; Unplaced.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0004867; F:serine-type endopeptidase inhibitor activity; IEA:UniProtKB-KW.
DR   CDD; cd00150; PlantTI; 1.
DR   InterPro; IPR000737; Prot_inh_squash.
DR   InterPro; IPR011052; Proteinase_amylase_inhib_sf.
DR   Pfam; PF00299; Squash; 1.
DR   PRINTS; PR00293; SQUASHINHBTR.
DR   SUPFAM; SSF57027; SSF57027; 1.
DR   PROSITE; PS00286; SQUASH_INHIBITOR; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Direct protein sequencing; Disulfide bond; Knottin;
KW   Protease inhibitor; Reference proteome; Secreted;
KW   Serine protease inhibitor.
FT   PEPTIDE         1..29
FT                   /note="Trypsin inhibitor 1"
FT                   /id="PRO_0000044376"
FT   SITE            5..6
FT                   /note="Reactive bond"
FT   DISULFID        3..20
FT                   /evidence="ECO:0000269|PubMed:2914611"
FT   DISULFID        10..22
FT                   /evidence="ECO:0000269|PubMed:2914611"
FT   DISULFID        16..28
FT                   /evidence="ECO:0000269|PubMed:2914611"
FT   HELIX           13..15
FT                   /evidence="ECO:0007829|PDB:1LU0"
FT   STRAND          21..23
FT                   /evidence="ECO:0007829|PDB:2STA"
FT   STRAND          26..28
FT                   /evidence="ECO:0007829|PDB:1LU0"
SQ   SEQUENCE   29 AA;  3275 MW;  CD509120BA52C01F CRC64;
     RVCPRILMEC KKDSDCLAEC VCLEHGYCG