Domain

Pancreatic trypsin inhibitor Kunitz domain (IPR002223)

Short name: Kunitz_BPTI

Domain relationships

None.

Description

The majority of the sequences having this domain belong to the MEROPS inhibitor family I2, clan IB; the Kunitz/bovine pancreatic trypsin inhibitor family, they inhibit proteases of the S1 family [PMID: 14705960] and are restricted to the metazoa with a single exception: Amsacta moorei entomopoxvirus. They are short (~50 residue) alpha/beta proteins with few secondary structures. The fold is constrained by 3 disulphide bonds. The type example for this family is aprotinin (bovine pancreatic trypsin inhibitor) [PMID: 1714504] (or basic protease inhibitor), but the family includes numerous other members [PMID: 1703675, PMID: 1593645, PMID: 8159751, PMID: 1304909], such as snake venom basic protease; mammalian inter-alpha-trypsin inhibitors; trypstatin, a rodent mast cell inhibitor of trypsin; a domain found in an alternatively-spliced form of Alzheimer's amyloid beta-protein; domains at the C-termini of the alpha(1) and alpha(3) chains of type VII and type VI collagens; and tissue factor pathway inhibitor precursor.

The pancreatic trypsin inhibitor (Kunitz) family [PMID: 6996568, PMID: 1703675, PMID: 1593645] is one of the numerous families of serine proteinase inhibitors. The basic structure of such a type of inhibitor is shown in the following schematic representation:

            +-----------------------+
            |  +--------+           |
            |  |      **|*******    |
          xxCxxC#xxxCxxxCxxxxxxCxxxxCxx
                    |          |
                    +----------+

            {------50 residues------}

'C': conserved cysteine involved in a disulfide bond.
'#': active site residue.
'*': position of the pattern.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0004867 serine-type endopeptidase inhibitor activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PRINTS
GENE3D
PROSITE profiles
Pfam
SUPERFAMILY
SMART