SUPERFAMILY 1.75 HMM library and genome assignments server

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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]

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

Functional annotation
General category Processes_IC
Detailed category Proteases

Function annotation of SCOP domain superfamilies

InterPro annotation
Cross references IPR000877 SSF57247 Protein matches

This family of eukaryotic proteinase inhibitors, belongs to MEROPS inhibitor family I12, clan IF. They inhibit serine peptidases of the S1 family [PubMed14705960].

The Bowman-Birk inhibitor family [PubMed6996568] 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 [PubMed3667571]. 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 [PubMed11375759, PubMed12325158, PubMed12643767].

InterPro database

PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.

Alignments of sequences to 15 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.

Browse and view proteins in genomes which have different domain combinations including a Bowman-Birk inhibitor, BBI domain.

Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.

Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 15 hidden Markov models representing the Bowman-Birk inhibitor, BBI superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Internal database links ]