Physiological action and biochemical components of snake venom

Abstract

U ovom radu opisala sam pregled otkrića otrova, njegovih svojstava i strukture, kroz povijest pa do danas. Pošto govoriti, odnosno pisati, o toksinima nije lako, morali smo proći i osnovnu podjelu zmija. Podjela prema dentaciji najjednostavnija je i opće prihvaćena. Prema njoj razlikujemo tri skupine: prednježljebozubice (Elapide), stražnježljebozubice (Colubride) i cjevozubice ( Viperide i Atraktaspidide). Prema dentaciji možemo ih podijeliti i na to koju „vrstu“ otrova posjeduju i kako ju ubrizgavaju. „Vrsta“ je pod navodnicima, jer zapravo niti jedna vrsta otrova nije u potpunosti čista. Zmije poput čegrtuša sa velikim udjelom hemotoksičnih komponenti u otrovu često zadrže i nešto neurotoksičnih komponenti. Isto vrijedi i za zmije poput taipana kod kojih prevladavaju neurotoksične komponente. Kada je prvi problem bio uspješno riješen, definiranje proteina i njihova uloga, moglo se krenuti na detaljnije istraživanje samih toksina. Utvrđeno je da je 90% građe toksina upravo proteinska te da za njihove analize mogu primijeniti sada utvrđene tehnike za analizu proteina. Prvenstveno se koristila kromatografija. Jedne od češćih bile su kromatografija ionskom izmjenom i gel filtracija (kromatografija na stupcu) koje su odvajale proteine na temelju različitog ionskog naboja ili određene molekulske mase.This work contains overview of history of discovery, structure and properties of snake venoms. Because writing about snake toxins is not an easy task, we needed to make some kind of classification of snakes themselves. The most common classification is based on their dentition. According to this classification there are three groups of snakes: front-fanged (proteroglyphous - Elapids), rear-fanged (opistoglyphous - Colubrids) and tubular-fanged (solenoglyphous – Vipers and atractaspids). Because of their dentition, we can differ which “kind” of poison snakes posses and how they inject it. “Kind” has quotation marks because no poison is completely pure. Snakes like rattlesnakes with big percentage of cytotoxic compounds in their venom always have some neurotoxic compounds. The same holds true for snakes like taipans, with big percentage of neurotoxic compounds, but also some cytotoxic components. When the first problem was solved, i.e. definition of proteins and their function, it was possible to move on to the research of toxins. It was discovered that 90% of snake toxin is made of proteins. The most often used method in this research was chromatography, specially ion exchange chromatography and gel filtration in which proteins can be divided on the basis of their ionic charge or molecular weight