Proteomic analysis to unravel the complex venom proteome of eastern India Naja naja: Correlation of venom composition with its biochemical and pharmacological properties

• Published in: Journal of proteomics Vol. 156; pp. 29 - 39
• Main Authors: Dutta, Sumita, Chanda, Abhishek, Kalita, Bhargab, Islam, Taufikul, Patra, Aparup, Mukherjee, Ashis K.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 06-03-2017
• Subjects: Acetylcholinesterase; Animals; Elapid Venoms - chemistry; Elapid Venoms - enzymology; Elapid Venoms - toxicity; Humans; India; LC-MS/MS; Naja naja; Pathophysiology; Phospholipase A2; Proteome - analysis; Proteomics - methods; Tandem Mass Spectrometry; Three-finger toxins; Venomics; LC-MS/MS; Tandem mass spectrometry; Venomics; Phospholipase A2; Pathophysiology; Three-finger toxins; Acetylcholinesterase; Phospholipase A
• ISSN: 1874-3919; 1876-7737
• DOI: 10.1016/j.jprot.2016.12.018

The complex venom proteome of the eastern India (EI) spectacled cobra (Naja naja) was analyzed using tandem mass spectrometry of cation-exchange venom fractions. About 75% of EI N. naja venom proteins were <18kDa and cationic at physiological pH of blood. SDS-PAGE (non-reduced) analysis indicated that in the native state venom proteins either interacted with each-other or self-aggregated resulting in the formation of higher molecular mass complexes. Proteomic analysis revealed that 43 enzymatic and non-enzymatic proteins in EI N. naja venom with a percent composition of about 28.4% and 71.6% respectively were distributed over 15 venom protein families. The three finger toxins (63.8%) and phospholipase A2s (11.4%) were the most abundant families of non-enzymatic and enzymatic proteins, respectively. nanoLC-ESI-MS/MS analysis demonstrated the occurrence of acetylcholinesterase, phosphodiesterase, cholinesterase and snake venom serine proteases in N. naja venom previously not detected by proteomic analysis. ATPase, ADPase, hyaluronidase, TAME, and BAEE-esterase activities were detected by biochemical analysis; however, due to a limitation in the protein database depository they were not identified in EI N. naja venom by proteomic analysis. The proteome composition of EI N. naja venom was well correlated with its in vitro and in vivo pharmacological properties in experimental animals and envenomed human.
Proteomic analysis reveals the complex and diverse protein profile of EI N. naja venom which collectively contributes to the severe pathophysiological manifestation upon cobra envenomation. The study has also aided in comprehending the compositional variation in venom proteins of N. naja within the Indian sub-continent. In addition, this study has also identified several enzymes in EI N. naja venom which were previously uncharacterized by proteomic analysis of Naja venom.
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•Proteomic analysis identified 43 proteins in the EI N. naja venom.•These 43 proteins belong to 15 families of snake venom proteins.•Non-enzymatic 3FTxs (63.8%) and enzymatic PLA2s (11.4%) are the most abundant proteins.•AChE, PDE, ChE and SVSPs have been reported for the first time in N. naja venom.•Its diverse venom proteome is liable for severe pathophysiology upon envenomation.