Reptile venom is a complex mixture of proteins. It is synthesized in specialized glands, stored for long periods, and rapidly activated upon deployment. This system is particularly well studied in front-fanged advanced snakes, including Colubridae and Atractaspididae.
크레스티드게코분양The venom glands of these species are associated with grooved anterior maxillary teeth and secreted under low pressure through a duct without insertion of adductor muscles. This venom is then injected by unique fangs during a bite.
Venom is a lethal secretion
Venom is a complex mixture of biological compounds secreted from specialized glands and delivered through fangs, stingers or spines. This lethal mixture contains toxins that cause a variety of effects, including paralysis, tissue necrosis, hemorrhage and coagulopathies. Reptiles use venom to kill and digest their prey and as a defense mechanism against threats. Snakes are one of the most venomous animals and have evolved many adaptations for utilizing their poison, including a unique system for delivering it.
Recent advances in -omics technologies have provided significant insights into the composition of snake venoms at exceptional levels of resolution. However, the underlying molecular mechanisms of venom production remain poorly understood. This is despite the fact that the chemical complexity of the major enzymes involved in venom synthesis and deployment is remarkable.
The venoms of snakes in the Elapidae, Crotalidae, and Viperidae families are complex mixtures of peptides that act on a variety of targets in different ways. These peptides include PLA2 enzymes, which catalyze the hydrolysis of the sn-2 ester bond in cell membrane phospholipids. These enzymes are characterized by their high molecular weight, 5-8 disulfide bridges and high affinity for negatively charged membrane regions. These features allow venoms to penetrate and disrupt cell membranes and trigger a number of cellular responses. These changes lead to the cataclysmic loss of homeostasis in prey, thereby causing fatal vascular dysfunction and apoptosis.
Venom is injected by fangs
Snakes have specialized fangs that inject deadly venom into their prey or defend themselves from predators. While most other animals use their fangs for stabbing or tearing meat, snake fangs have small grooves or hollows that direct venom into the wound caused by a bite. This unique feature distinguishes them from other reptiles, and scientists have long sought to understand how snakes evolved specialized venom-delivery teeth.
A team led by University of Alberta biology grads and post-doctoral researchers has shed new light on this question. Using high-tech modeling, fossils, and hours of microscopic observations, they found that snakes have turned tiny infoldings at the base of their teeth, called plicidentine, into deep channels that carry venom towards the tip of their teeth. The scientists believe that this mechanism allows for a more effective and rapid delivery of venom to the prey.
The study also shows that the development of venom grooves can be independent of an adjacent venom gland or duct. This is in contrast to front-fanged colubroids, which lack grooved fangs despite having the Duvernoy’s gland (the most primitive colubroid venom gland) nearby. The findings suggest that venom grooves developed independently in different snake clades and are an important step toward understanding how these complex venom delivery systems evolved.
Venom is a natural gift
Venom is a natural gift from the reptile kingdom. It has been used for killing prey and is also a defence against predator species. It has been used by leeches, scorpions, centipedes and lizards to kill their enemies. Scientists have found that venom contains many bioactive proteins and peptides with potential drug applications. In fact, venom is the source of two drugs that are approved by the FDA for treating arthritis symptoms and blood-clotting disorders: exenatide and lixisenatide.
The diversity of snake venom composition is a rich playground for medicinal chemists, as it provides a collection of toxins with various biological activity. However, the geographic and taxonomic diversity of snake species results in a wide range of specificity that complicates the development of antivenoms.
In the past, it was difficult to decipher the structural and functional details of the toxins present in snake venom. But the discovery of three-finger toxins, such as a-bungarotoxin from the venom of the krait Bungarus multicinctus, has opened new doors for analyzing their structure and function.
The venom of a particular snake species can contain up to 30 protein families. Each family may have hundreds of different isoforms. One protein from the venom of the mamba Sistrurus catenatus edwardsii, omwaprin, is particularly interesting because it displays dose-dependent and strain-specific antibacterial and hemolytic activity. The peptide also exhibits a unique structure, with an amidated C-terminal arginine. The amino acid modification is unique among snake venom toxins and appears to contribute to its potent activity against the a7 subunit of nAChR.
Venom is a weapon
Snakes have the ultimate weapon – their venom. It is their natural gift and helps them hunt and protect themselves against prey species. But this lethal secretion also causes harm to humans. Approximately 5 people die from snake bites each year. It is a major problem in Africa and Asia, especially among agricultural workers. To reduce the incidence of snakebite, scientists are developing anti-venoms. These drugs bind to the toxin and prevent it from reaching its target. However, they are not effective against all types of venom. The pharmacology of snake venom is complex, and the toxicity of a particular species’ venom can be difficult to predict.
The research field of snake venom is tightly intertwined with biochemistry, molecular biology, genetics, physiology, pathophysiology and a rapidly expanding area known as clinical toxinology. It is a fascinating area of research that challenges us to redefine the concept of systems in biology.
A snake’s venom is a combination of simple to complex polypeptides that are injected into the prey animal by special delivery systems (like fangs or stinging cells). Insect and fish venoms contain toxins that attack specific organs and tissues. In the case of snakes, venom attacks the circulatory and nervous system. It can even paralyze and kill the animal. But snakes use their venom primarily as defensive weapons.