Proteomic analysis of snake venom obtained from Naja melanoleuca in Ghana

The venom of most poisonous snakes consists of active proteins that are responsible for most of the lethal effects of snakebite envenomation. To guide the development of targeted antivenom, a deeper understanding of venom compositions is necessary. The present study aimed to characterize the protein composition and to evaluate the lethality of Naja melanoleuca venom obtained in Ghana. Crude venom was collected, lyophilized and protein concentration quantified using the Bradford Assay. The protein profile and molecular weight distribution of the venom were evaluated using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), while reverse-phase high-performance liquid chromatography coupled with mass spectrometry (RP-HPLC-MS) was employed to separate protein fractions and to determine intact protein masses. The venom toxicity was assessed by determining the median lethal dose (LD50) in mice using the probit regression method. The protein concentration of the venom was 2.917 mg/mL, while the SDS-PAGE analysis showed protein bands with estimated molecular weights ranging from 10.98 kDa to 122.53 kDa. The relative abundance of protein bands in the LC-MS data suggested that low-molecular-weight proteins dominated the venom. The average LD50 of the venom was 1.17 mg/kg within the range of 0.50-1.84 mg/kg, which confirmed its high toxicity. This study provided one of the first proteomic datasets describing Ghanaian N.melanoleuca venom with baseline information on its protein composition and toxicity. These findings laid the foundation for future proteomic, pharmacological and toxicological investigations to develope local antivenoms for improved snakebite management.