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

Abstract

Cobra snakes, including <i>Naja mossambica</i> and <i>Naja nigricincta nigricincta,</i> are one of the major groups of snakes responsible for snakebites in southern Africa, producing significant cytotoxicity and tissue damage. The venom of <i>N. mossambica</i> has been briefly characterised, but that of <i>N. n. nigricincta</i> is not reported. The current study identifies the venom proteins of <i>N. mossambica</i> and <i>N. n. nigricincta</i>. 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. <i>N. mossambica</i> was found to have 75 proteins in total (from 16 protein families), whereas <i>N.n. nigricincta</i> 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.