Danger in the reef: Proteome, toxicity, and neutralization of the venom of the olive sea snake, Aipysurus laevis

Abstract

Four specimens of the olive sea snake, Aipysurus laevis, were collected off the coast of Western Australia, and the venom proteome was characterized and quantitatively estimated by RP-HPLC, SDS-PAGE, and MALDI-TOF-TOF analyses. A. laevis venom is remarkably simple and consists of phospholipases A2 (71.2%), three-finger toxins (3FTx; 25.3%), cysteine-rich secretory proteins (CRISP; 2.5%), and traces of a complement control module protein (CCM; 0.2%). Using a Toxicity Score, the most lethal components were determined to be short neurotoxins. Whole venom had an intravenous LD50 of 0.07 mg/kg in mice and showed a high phospholipase A2 activity, but no proteinase activity in vitro. Preclinical assessment of neutralization and ELISA immunoprofiling showed that BioCSL Sea Snake Antivenom was effective in cross-neutralizing A. laevis venom with an ED50 of 821 μg venom per mL antivenom, with a binding preference towards short neurotoxins, due to the high degree of conservation between short neurotoxins from A. laevis and Enhydrina schistosa venom. Our results point towards the possibility of developing recombinant antibodies or synthetic inhibitors against A. laevis venom due to its simplicity.

Strategies in ‘snake venomics’ aiming at an integrative view of compositional, functional, and immunological characteristics of venoms

“…This concept was developed with the purpose of identifying which venom components should be targeted by novel neutralizing agents under development, such as recombinant human antibodies or synthetic peptide inhibitors [82]. Several investigations on elapid snake venoms have succeeded in pinpointing the main targets to be inhibited by using this experimental ‘toxicovenomics’ approach [73, 74, 78, 79]. …”

Assessing the Binding of Venoms from Aquatic Elapids to the Nicotinic Acetylcholine Receptor Orthosteric Site of Different Prey Models

“…This low binding has been previously suggested to potentially be due to the proportions of 3FTxs within the venom [ 55 ], i.e., a low concentration of 3FTx might give a weaker binding detection than a venom with high concentrations of 3FTxs. However, this does not seem likely in the case of many of these aquatic elapids, as their venoms have been shown to be dominated by 3FTxs in high proportions [ 47 , 48 , 49 , 50 , 51 ]. Furthermore, the venoms of Hydrophis caerulescens , H. peronii , H. schistosus and M. surinamensis did not bind to any mimotope ( Figure 1 ).…”

“…The venom compositions of many aquatic snakes are composed mostly of neurotoxic 3FTxs—in some cases >75% of the venom composition—along with phospholipase A 2 (PLA 2 ) toxins [ 47 , 48 , 49 , 50 , 51 , 52 , 53 ]. Given the rapid onset of neurotoxic pathologies produced by many neurotoxins within these toxin classes, venoms possessing large proportions of these toxin types again suggest the need for fast immobilisation as a key selection pressure in aquatic environments.…”

Guiding recombinant antivenom development by omics technologies

“…Additionally, intraspecies venom variation is a common phenomenon [17,18], which may further complicate design of effective immunization mixtures. Although differences in antibody responses also occur among immunized animals for antivenoms, variation in response can to some extent be controlled using standardized immunogens, such as (multi)epitope DNA strings, synthetic peptides, or recombinant toxins [6].…”

“…However, when used conservatively to select the toxins which are essential to neutralize in order to abrogate overall venom toxicity, the toxicovenomics approach may provide a robust roadmap for antitoxin discovery. So far only elapid snake species from the Naja, Dendroaspis, and Aipysurus genera have been investigated by toxicovenomics [18,90,[92][93][94]. However, researchers from Mexico have recently employed a similar approach for selecting which toxins from Mexican scorpions to focus antibody discovery efforts on [53].…”