SUPERFAMILY 1.75 HMM library and genome assignments server

An insect antifreeze protein superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   All beta proteins [ 48724] (174)
Fold:   Single-stranded left-handed beta-helix [ 51160] (4)
Superfamily:   An insect antifreeze protein [ 51177]
Families:   An insect antifreeze protein [ 51178]

Superfamily statistics
Genomes (1) Uniprot 2014_06 PDB chains (SCOP 1.75)
Domains 1 33 3
Proteins 1 33 3

Functional annotation
General category Metabolism
Detailed category Other enzymes

Function annotation of SCOP domain superfamilies

InterPro annotation
Cross references IPR007928 SSF51177 Protein matches

Antifreeze proteins (AFPs) are a class of proteins that are able to bind to and inhibit the growth of macromolecular ice, thereby permitting an organism to survive subzero temperatures by decreasing the probability of ice nucleation in their bodies [PubMed15291806]. These proteins have been characterised from a variety of organisms, including fish, plants, bacteria, fungi and arthropods. This entry represents insect AFPs of the type found in spruce budworm, Choristoneura fumiferana.

The structure of these AFPs consists of a left-handed beta-helix with 15 residues per coil [PubMed12015145]. The beta-helices of insect AFPs present a highly rigid array of threonine residues and bound water molecules that can effectively mimic the ice lattice. As such, beta-helical AFPs provide a more effective coverage of the ice surface compared to the alpha-helical fish AFPs.

A second insect antifreeze from Tenebrio molitor also consists of beta-helices, however in these proteins the helices form a right-handed twist; these proteins show no sequence homology to the current entry, but may act by a similar mechanism. The beta-helix motif may be used as an AFP structural motif in non-homologous proteins from other (non-fish) organisms as well.

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

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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 2 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 An insect antifreeze protein 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 2 hidden Markov models representing the An insect antifreeze protein 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 ]