Bowman-Birk inhibitor, BBI superfamily

SCOP classification

• Root: SCOP hierarchy in SUPERFAMILY [ 0] (11)
• Class: Small proteins [ 56992] (90)
• Fold: Knottins (small inhibitors, toxins, lectins) [ 57015] (19)
• Superfamily: Bowman-Birk inhibitor, BBI [ 57247]
• Families: Bowman-Birk inhibitor, BBI [ 57248]

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Superfamily statistics

	Genomes (28)	Uniprot 2018_03 genome	PDB chains (SCOP 1.75)
Domains	456	997	15
Proteins	301	729	13

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Functional annotation

• General category: Processes_IC
• Detailed category: Proteases

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InterPro annotation

• Cross references: IPR000877 SSF57247 Protein matches
• Abstract:

  This family of eukaryotic proteinase inhibitors, belongs to MEROPS inhibitor family I12, clan IF. They inhibit serine peptidases of the S1 family [14705960].

  The Bowman-Birk inhibitor family [6996568] is one of the numerous families of serine proteinase inhibitors. They have a duplicated structure and generally possess two distinct inhibitory sites. These inhibitors are primarily found in plants and in particular in the seeds of legumes as well as in cereal grains. In cereals they exist in two forms, one of which is a duplication of the basic structure [3667571]. Proteins of the Bowman-Birk inhibitor family of serine proteinase inhibitors interact with the enzymes they inhibit via an exposed surface loop that adopts the canonical proteinase inhibitory conformation. The resulting non-covalent complex renders the proteinase inactive. This inhibition mechanism is common for the majority of serine proteinase inhibitor proteins and many analogous examples are known. A particular feature of the Bowman-Birk inhibitor protein, however, is that the interacting loop is a particularly well-defined disulphide-linked short beta-sheet region [11375759, 12325158, 12643767].

InterPro database

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