omega-Atracotoxin

{{Short description|Insect-specific neurotoxin}}

{{DISPLAYTITLE:omega-Atracotoxin}}

{{Pfam_box

| Symbol = Omega-toxin

| Name = ω-Atracotoxin

| image =

| width =

| caption =

| Pfam= PF06357

| InterPro= IPR009415

| SMART=

| Prosite =

| SCOP = 1hvw

| TCDB =

| OPM family=

| OPM protein=

| PDB=

{{PDB3|1hvw}}A:4-23 {{PDB3|1axh}} :1-37

}}

omega-Atracotoxin (ω-atracotoxin) is an insect-specific neurotoxin produced by the Blue Mountains funnel-web spider. Its phylogenetic specificity derives from its ability to antagonise insect, but not vertebrate, voltage-gated calcium channels. Two spatially proximal amino acid residues, Asn(27) and Arg(35), form a contiguous molecular surface that is essential for toxin activity. It has been proposed that this surface of the beta-hairpin is a key site for interaction of the toxin with insect calcium channels.{{cite journal |vauthors=King GF, Fletcher JI, Tedford HW |title=Functional significance of the beta hairpin in the insecticidal neurotoxin omega-atracotoxin-Hv1a |journal=J. Biol. Chem. |volume=276 |issue=28 |pages=26568–26576 |year=2001 |pmid=11313356 |doi=10.1074/jbc.M102199200|doi-access=free }}