title: Proteomic investigation of Sri Lankan hump-nosed pit viper (Hypnale hypnale) venom.
abstract: The hump-nosed pit viper, Hypanle hypnale, contributes to snakebite mortality and morbidity in Sri Lanka. Studies showed that the venom is hemotoxic and nephrotoxic, with some biochemical and antigenic properties similar to the venom of Calloselasma rhodostoma (Malayan pit viper). To further characterize the complexity composition of the venom, we investigated the proteome of a pooled venom sample from >10 Sri Lankan H. hypnale with reverse-phase high performance liquid chromatography (rp-HPLC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and peptide sequencing (tandem mass-spectrometry and/or N-terminal sequencing). The findings ascertained that two phospholipase A2 subtypes (E6-PLA2, W6-PLA2) dominate the toxin composition by 40.1%, followed by snake venom metalloproteases (36.9%), l-amino acid oxidase (11.9%), C-type lectins (5.5%), serine proteases (3.3%) and others (2.3%). The presence of the major toxins correlates with the venom's major pathogenic effects, indicating these to be the principal target toxins for antivenom neutralization. This study supports the previous finding of PLA2 dominance in the venom but diverges from the view that H. hypnale venom has low expression of large enzymatic toxins. The knowledge of the composition and abundance of toxins is essential to elucidate the pathophysiology of H. hypnale envenomation and to optimize antivenom formulation in the future.
authors.affiliation: Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; University of Malaya Proteomic Centre for Research (UMPCR), University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Choo Hock
authors.initials: CH
authors.lastname: Tan
authors.affiliation: Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; University of Malaya Proteomic Centre for Research (UMPCR), University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Nget Hong
authors.initials: NH
authors.lastname: Tan
authors.affiliation: Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Si Mui
authors.initials: SM
authors.lastname: Sim
authors.affiliation: Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; University of Malaya Proteomic Centre for Research (UMPCR), University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Shin Yee
authors.initials: SY
authors.lastname: Fung
authors.affiliation: Department of Clinical Medicine, Faculty of Medicine, University of Colombo, Sri Lanka.
authors.forename: Christeine Ariaranee
authors.initials: CA
authors.lastname: Gnanathasan
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003435:Crotalid Venoms / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D013058:Mass Spectrometry; D054467:Phospholipases A2 / Q000235:genetics; D020543:Proteome / Q000235:genetics*; D040901:Proteomics / Q000379:methods*; D013188:Sri Lanka; D017819:Viperidae
chemical_list: D003435:Crotalid Venoms; D020543:Proteome; D054467:Phospholipases A2
keywords: Hypnale hypnale; N-terminal sequence; Phospholipase A(2); Reverse-phase HPLC; Tandem mass spectrometry; Venom proteomics