Spooky toxin (SsTx) is a small
peptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides.
...
neurotoxin. It is found in the
venom
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a st ...
of
Chinese red-headed centipede
The Chinese red-headed centipede, also known as the Chinese red head, (''Scolopendra subspinipes mutilans'') is a centipede from East Asia and Australasia. It averages 20 cm (8 in) in length and lives in damp environments.
In anc ...
s (''Scolopendra subspinipes mutilans''), also known as golden head centipedes. It is originally composed of 76 amino acids (sequence: MEKKIIFLVFLVAL
LALPGFISTEVIKK
DTPYKKRKFPYKSEC
LKACATSFTG
GDESRIQEGKPG
FFKCTCYFTTG, disulfide bonds Cys43-Cys69,
Cys47-Cys71), with a molecular weight of 6017.5 Daltons, but loses the first 23 residues and becomes 53 residues long (sequence
EVIKKDTPYKKRKFPYKSECLKACATSFTGGDESRIQEGKPGFFKCTCYFTTG, disulfide bonds Cys20-Cys46, Cys24-Cys48). SsTx is currently thought to be unique to ''Scolopendra subspinipes mutilans''.
By blocking
KCNQ channels KCQN genes encode family members of the Kv7 potassium channel family. These include Kv7.1 (KCNQ1) - KvLQT1, Kv7.2 ( KCNQ2), Kv7.3 ( KCNQ3), Kv7.4 ( KCNQ4), and Kv7.5 (KCNQ5). Four of these (KCNQ2-5) are expressed in the nervous system. They constitu ...
(preventing potassium from flowing into and out of cells) SsTx disrupts cardiovascular, respiratory, muscular, and nervous systems; where snake venoms typically only affect circulatory or nervous systems, and venom from spiders, scorpions, and snails typically only target nervous systems. This allows for golden headed centipedes to target larger prey up to 15 times their size.
Applications
The venom of the ''Scolopendra subspinipes mutilans'' is already being widely used as a
traditional medicine
Traditional medicine (also known as indigenous medicine or folk medicine) comprises medical aspects of traditional knowledge that developed over generations within the folk beliefs of various societies, including indigenous peoples, before the ...
in Asian countries. Claimed medicinal uses include antimicrobial, antibacterial, and anticancer.
See also
*
Charybdotoxin
References
Centipede toxins
Neurotoxins
Ion channel toxins
Potassium channel blockers
Protein toxins
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