A chemist at the Vienna University of Technology (TU Vienna) is looking for unusual structures in snake venom and plans to prove their medical effectiveness.
What in the 1950s led to the development of Captopril, a drug for the treatment of hypertension, is being continued in an interesting new chapter with the analysis of venom from South American pit vipers and tropical rattlesnakes.
"We receive the snake venom as a yellow crystalline powder in ampules directly from the Instituto Butantan in São Paulo, Brazil. That is a well-known scientific institution, also popular with tourists, which studies some of the most poisonous snake species in the world," explains Martina Marchetti, assistant professor at the Institute for Chemical Technologies and Analytics at the Vienna University of Technology (TU Vienna).
Her investigations focus on the venoms of four different pit vipers (Bothrops) as well as a tropical rattlesnake (Crotalus durissus terrificus). All five species are native to South America. They are among the most aggressive snake varieties there. Every year in South America, 2.5 million people are bitten by snakes. About 100,000 die as a result.
Marchetti analyzes the snake venoms by various methods. She and her coworkers use lab-on-a-chip technology to determine the composition of the toxins and analyze peptide chains (linear sequences of amino acids). The structures of individual members of these chains are then analyzed using tandem mass spectrometry. Two-dimensional gel electrophoresis offers another option for separating samples by molecular weight and pH.
According to Marchetti, "Not every snake venom is the same. Time and again we encounter unusual new structures. The goal of our research is to find out why individual components of the venom act in a particular way and what they may have to offer to the pharmaceutical industry."
A deliberately administered toxic effect in the right amount can actually be beneficial to human health. Snake toxins have a very broad field of potential use, including antibacterial applications, cell growth inhibition, nerve stimulation, blood thinning and clotting. Their effects are also being tested for the treatment of Alzheimer's disease.
As a result of proteome research, which has become popular in recent years, a number of new analytical methods have been developed. Combinations of these methods allow to uncover clues in order to solve the riddle of the medical effectiveness of snake venom. Of course, another goal is to develop effective antivenoms, which, according to Marchetti, "might some day be available to take along in tablet form."
Her investigations have been conducted in collaboration with Walter Welz at the Johannes Kepler University in Linz. Researchers first noticed the pharmacological effectiveness of snake venoms in the process of developing antisera. Such investigations in the 1950s resulted in the development of the hypertension drug Captopril, for which the structural information from a peptide (protein) isolated from snake venom served as an archetype.
Source: Vienna University of Technology