A study on cardiotoxin of Sri Lankan Cobra

Abstract

Sri Lanka has the highest fatality rate of snakebites in the world. The cobra (𝘕𝘢𝘫𝘢 𝘯𝘢𝘫𝘢 𝘯𝘢𝘫𝘢) is one the most dangerous species in the Indian subcontinent. Anti venom serum (AVS) is the only effective therapy available for treatment of snake bite. Anaphylaxis can be fatal unless emergency treatment is given. At this juncture, it is worthwhile to investigate the composition of the toxins of Sri Lankan cobra and find out their homogeneity to Indian species.

In this study, venom was collected from captured cobras reared at the reptile facility in the Faculty of Medicine, University of Peradeniya. Crude venom was purified by chromatographic met;hods and the purified product was subjected to protein sequencing. The cardiotoxin of Sri Lankan cobra which is responsible for tissue reactions and haematological changes after envenomation was analysed. In order to clarify the structural relationship among them, amino acid sequence of cardiotoxins determined in this study were compared with those of cardiotoxins already reported in other cobra species.

The amino acid sequences of the cardiotoxin, present in the Sri Lankan cobra is different from other Asian cobras. It is much closer to 𝘕𝘢𝘫𝘢 𝘯𝘢𝘫𝘢 𝘰𝘹𝘪𝘢𝘯𝘢. This study supports the view that there are genetical differences between the Sri Lankan and Indian cobra species. It is beneficial to analyse the major toxins of our endogenous snakes and produce anti venom specific to our species in Sri Lanka, thereby helping to reduce the high fatality due to snakebite.