The spider venoms often contain many active peptides such as neurotoxins,
lectins, inhibitors to enzyme, etc. These peptides are very important for
spider's hunting and defending. During the long history of spider evolution,
the peptides evolved into different structures and functions. Despite their
different biological functions the following peptides appear to have evolved
from the same ancestors and belong to the huwentoxin-1 family :
Ornithoctonus huwena (Chinese bird spider) (Selenocosmia huwena)
huwentoxin-I (HWTX-I), a 33 amino acid peptide, which can block the N-type
high-voltage activated calcium channels .
Brachypelma smithii (Mexican red knee tarantula) Venom protein 5.
Grammostola spatulata (Chilean rose tarantula) voltage sensor toxin 1.
Peptides of the huwentoxin type I family contain 6 cysteine residues involved
in three disulfide bonds. The three disulfide bridges have been assigned as
C1-C4, C2-C5 and C3-C6. HWTX-I adopts a compact structure consisting of a
small triple-stranded antiparallel β-sheet and five β-turns (see
We developed a pattern for huwentoxin-1 family proteins, which have a
[C-C-CC-C-C] cysteine arrangement. The three-dimensional structure of
huwentoxin-1 family proteins possess a knottin scafold (see <PDOC60004>) [E1].
PROSITE is copyright. It is produced by the SIB Swiss Institute
Bioinformatics. There are no restrictions on its use by non-profit
institutions as long as its content is in no way modified. Usage by and
for commercial entities requires a license agreement. For information
about the licensing scheme send an email to
or see: prosite_license.html.