Crotamine

Crotamin 1H5O

Crotamine is a toxin found in the venom of the South American rattlesnake (Crotalus durissus). It is a small, basic protein that is known for its ability to cause muscle spasms and paralysis. Crotamine is one of the primary components of the venom and contributes to its overall toxicity.

Structure and Properties

Crotamine is a polypeptide consisting of 42 amino acids. It has a molecular weight of approximately 4.8 kDa. The protein is highly basic due to the presence of multiple lysine and arginine residues. The structure of crotamine includes three disulfide bridges, which contribute to its stability and biological activity.

Mechanism of Action

Crotamine exerts its effects by interacting with voltage-gated sodium channels in muscle cells. It binds to these channels and alters their function, leading to an influx of sodium ions. This results in depolarization of the muscle cell membrane, causing muscle contractions and spasms. Prolonged exposure to crotamine can lead to muscle paralysis.

Biological Effects

The primary biological effects of crotamine include:

• Muscle spasms
• Paralysis
• Pain
• Swelling at the site of envenomation

In severe cases, crotamine can cause respiratory failure due to paralysis of the respiratory muscles.

Medical Research

Crotamine has been studied for its potential therapeutic applications. Research has explored its use as a drug delivery system due to its ability to penetrate cell membranes. Additionally, crotamine's selective toxicity to certain types of cells has been investigated for potential use in cancer treatment.

Related Toxins

Crotamine is part of a larger family of toxins found in snake venom. Other related toxins include:

• Crotoxin
• Bothropstoxin
• Phospholipase A2

See Also

• Snake venom
• Neurotoxin
• Myotoxin
• Crotalus durissus