SUPERFAMILY 1.75 HMM library and genome assignments server

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Neurotoxin B-IV superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   Small proteins [ 56992] (90)
Fold:   Toxic hairpin [ 57006] (4)
Superfamily:   Neurotoxin B-IV [ 57011]
Families:   Neurotoxin B-IV [ 57012]

Superfamily statistics
Genomes (1) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 1 3 1
Proteins 1 3 1

Functional annotation
General category Processes_EC
Detailed category Toxins/defense

Function annotation of SCOP domain superfamilies

InterPro annotation
Cross references IPR012497 SSF57011 Protein matches

The members of this family resemble neurotoxin B-IV , which is a crustacean-selective neurotoxin produced by the marine worm Cerebratulus lacteus. This highly cationic peptide is approximately 55 residues and is arranged to form two antiparallel helices connected by a well-defined loop in a hairpin structure. The branches of the hairpin are linked by four disulphide bonds. Three residues identified as being important for activity, namely Arg-17, -25 and -34, are found on the same face of the molecule, while another residue important for activity, Trp30, is on the opposite side. The protein's mode of action is not entirely understood, but it may act on voltage-gated sodium channels, possibly by binding to an as yet uncharacterised site on these proteins. Its site of interaction may also be less specific, for example it may interact with negatively charged membrane lipids [PubMed9180379].

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 1 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 Neurotoxin B-IV 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 1 hidden Markov models representing the Neurotoxin B-IV 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 ]