Protein Identification of Venoms of the African Spitting Cobras, Naja mossambica and Naja nigricincta nigricincta

Ottilie Katali,Erastus Haindongo,John Eriksson,Timothy Rennie,Peter Nyarangó,Peter James,Mirva Pääkkönen,Christian John Hunter,Loide Shipingana

doi:10.3390/toxins12080520

Abstract

Cobra snakes, including Naja mossambica and Naja nigricincta nigricincta, are one of the major groups of snakes responsible for snakebites in southern Africa, producing significant cytotoxicity and tissue damage. The venom of N. mossambica has been briefly characterised, but that of N. n. nigricincta is not reported. The current study identifies the venom proteins of N. mossambica and N. n. nigricincta. This is achieved using sodium dodecyl sulphate (SDS)-polyacrylamide gel eletrophroresis (PAGE), followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Most of the proteins were less than 17 kDa in both snakes. N. mossambica was found to have 75 proteins in total (from 16 protein families), whereas N.n. nigricincta had 73 (from 16 protein families). Of these identified proteins, 57 were common in both snakes. The proteins identified belonged to various families, including the three-finger toxins (3FTx), Cysteine-rich secretory proteins (CRiSP), Phospholipase A2 (PLA2) and Venom metalloproteinase M12B (SVMP). The current study contributes to the profile knowledge of snake venom compositions, which is of fundamental value in understanding the proteins that play a major role in envenomation.

Highlights

Snakebites are a major cause of morbidity and mortality in Africa, Asia and Latin America, [1,2], yet, a neglected tropical disease—mostly affecting remote and rural tropical regions [3,4,5]
The sodium dodecyl sulphate (SDS)-polyacrylamide gel eletrophroresis (PAGE) results indicated that most of the proteins were less than 17 kDa in both N. mossambica and N.n. nigricincta, as shown in cluster one (Figure 2)
The high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) raw data files were searched with Proteome Discoverer 2.2 software (Thermo Fisher Scientific, Waltham, MA, USA)

Summary

Introduction

Snakebites are a major cause of morbidity and mortality in Africa, Asia and Latin America, [1,2], yet, a neglected tropical disease—mostly affecting remote and rural tropical regions [3,4,5]. These snakebites were caused by different snakes, including spitting cobra snakes, and a large proportion of the people bitten were children under the age of six-years-old—and many of these children suffered long-term disability [8]. N. nigricincta woodi (black spitting cobra) [9,10,11,12] (Figure 1).

Methods

Results

Conclusion