SUPERFAMILY 1.75 HMM library and genome assignments server


Avidin/streptavidin superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   All beta proteins [ 48724] (174)
Fold:   Streptavidin-like [ 50875] (8)
Superfamily:   Avidin/streptavidin [ 50876]
Families:   Avidin/streptavidin [ 50877] (2)


Superfamily statistics
Genomes (62) Uniprot 2014_06 PDB chains (SCOP 1.75)
Domains 134 259 40
Proteins 131 258 40


Functional annotation
General category Metabolism
Detailed category Coenzyme metabolism and transport

Document:
Function annotation of SCOP domain superfamilies

UniProtKB KeyWords (KW)

(show details)
KW termFDR (all)SDKW levelAnnotation (direct or inherited)
Cellular componentSecreted0Moderately InformativeDirect
DomainSignal0Least InformativeDirect
Molecular functionBiotin0Highly InformativeDirect
Post-translational modificationGlycoprotein1.331e-10Least InformativeDirect
Post-translational modificationDisulfide bond7.132e-10Least InformativeDirect

Document: KW annotation of SCOP domains

InterPro annotation
Cross references IPR005468 SSF50876 Protein matches
Abstract Avidin [PubMed2388586] is a minor constituent of egg white in several groups of oviparous vertebrates. Avidin, which was discovered in the 1920's, takes its name from the avidity with which it binds biotin. These two molecules bind so strongly that is extremely difficult to separate them. Streptavidin is a protein produced by Streptomyces avidinii which also binds biotin and whose sequence is evolutionary related to that of avidin.

Avidin and streptavidin both form homotetrameric complexes of noncovalently associated chains. Each chain forms a very strong and specific non-covalent complex with one molecule of biotin.

The three-dimensional structures of both streptavidin [PubMed2928324, PubMed8515446] and avidin [PubMed2784773] have been determined and revealed them to share a common fold: an eight stranded anti-parallel beta-barrel with a repeated +1 topology enclosing an internal ligand binding site.

Fibropellins I and III [PubMed8500658] are proteins that form the apical lamina of the sea urchin embryo, a component of the extracellular matrix. These two proteins have a modular structure composed of a CUB domain (see), followed by a variable number of EGF repeats and a C-terminal avidin-like domain.


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 · UniProtKB KeyWords (KW) ]

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 4 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 Avidin/streptavidin 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 4 hidden Markov models representing the Avidin/streptavidin 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 · UniProtKB KeyWords (KW) · Internal database links ]