Venoms and Toxins
Latest Publications

Introduction: The health challenges associated with cassava products as a common staple food for approximately 70% of Africans and part of Asia pose a looming danger due to Bacillus enterotoxins’ presence in the processing environment. Objective: This study investigated the presence of enterotoxigenic genes namely, Bacillus cereus enterotoxin T (bceT), hemolysin bl (hblC, hblD) and non-haemolytic enterotoxin (nheA, nheB and nheC) from Bacillus species isolated from soil of cassava processing environment. Methods: Soil samples from 20 cassava processing sites in Ile-Ife and Modakeke, Nigeria were collected and cultured on Nutrient agar at 37 ºC for 24 hours. Colonies phenotypically identified as Bacillus were identified using Bacillus-specific 16S rRNA-targeted PCR technique. Screened Bacillus spp were assessed for the presence of enterotoxigenic genes using PCR with previously reported primers. Results: A total of 100 Bacillus isolates were selected from this study with Bacillus macerans (33 %) showing the highest frequency of occurrence among the identified species, however, 74 isolates were molecularly confirmed as Bacillus. Amongst the 74 molecularly confirmed Bacillus isolates, 28 (37.84%), 35 (47.30 %) and 37 (50 %) has nhe, hbl and bceT genes respectively. Investigation showed that 42 (56.76 %) of the Bacillus species encoded at least one of the screened enterotoxin genes. Conclusion: The presence of these 3 sets of enterotoxin genes in Bacillus isolated from cassava processing sites calls for immediate attention as they could be pivotal in the release of toxins in cassava products, cause lethal effects via consumption. This study demonstrates the possibility of foodborne disease outbreaks in Bacillus toxin-laden cassava products processed under unhygienic conditions.

Background: Development of antivenom or antidote requires the repetition of immunization of large animals, such as horses and goats, which ultimately releases the IgG immunoglobulin produced in the serum specimen. As snake venom involves a variety of proteins and enzymes getting administered into the animal, this process can inflict significant harm to the animal, therefore choosing carriers that can deliver the least amount of venom could be a safer option for animal immunization Objective: In this research, nanoliposomes were used to encapsulate venom as a protected cargo for immunization. We used two distinct liposomal formulations to entrap the venom: 1,2-distearoyl-sn-glycero-3-phosphocholine, 1,2-distearoyl-sn-glycero-3-phospho-(1′-rac-glycerol) associated with cholesterol in one formulation and dimethyldioctadecylamonium (Bromide salt) paired with cholesterol in the other. Method: Liposomal formulations prepared by solvent evaporation method and the venom was encapsulated in liposomes and evaluated for size and zeta potential. Meanwhile, encapsulation efficiency, venom release percentage, and phospholipase activity have all been analyzed. Results: The findings revealed that dimethyldioctadecylamonium (Bromide salt) combined with cholesterol had the highest encapsulation efficiency. In this formulation, the venom release rate had a steady-state profile. The lack of phospholipase activity in this formulation may be due to a bromide group in the liposomal structure that could be useful for immunization. Conclusion: Liposomal formulations, which do not have the active site of the snake venom enzymes, could be used for venom encapsulation.

: Venom toxins have specific molecular targets that result in envenomated complications such as neurotoxicity. During evolution, the composition of the venom has been evolved synchronously with the evolution of molecular targets. Venom is an important tool for humans from two different perspectives; venom advantages and disadvantages. Meanwhile, clinical and pharmacological applications of venoms due to their specific targeting and modulation of physiological elements or targets are notable in various disorders. The better understanding of venoms and their composition will improve the practical applications of some toxin-based drugs in drugstoresin the future.

: A diversity of marine invertebrates, such as cnidarians are rich sources of large bio-active molecules. This chemo-diversity of bio-active compounds has a promising potential in several biotechnological and therapeutic applications. On the basis of a comparative bibliographic approach, we intend in this review to present and discuss an overview of: i) the diversity of marine invertebrates as a candidate for bio-active molecules production; ii) the diversity of bio-active compounds and venom derived from these organisms; iii) the relationship between, the diversity of these marine organisms and the structure of the toxins they secrete. In this bibliographic study, a focus is going to be made on protein neurotoxins targeting ion channels. We also discuss the potential link between the bioecological characteristics of cnidarians and the diversity of toxins.

Background: Cholera is a life-threatening secretory diarrheal disease caused by Vibrio cholera bacterium. On the contrary, local and specific use of cholera toxin (CT) at a low concentration can cause controlled fluid secretion. In the study, we explored the secretory action of CT in the intestine of rats with acute renal failure (ARF). Methods: Closed intestinal loop experiments were performed in ARF rats treated with CT. Secreted fluid and serum were analyzed for various ¬solutes and electrolytes. The presence of K+, Na+, Cl-, urea and creatinine were monitored. Histopathology analysis was carried out to evaluate the effect of CT in liver, kidney, and intestinal tissues. Results: A reduction in the absorption of water and electrolytes was observed over time and a secretory response started to appear within hours of CT treatment. The fluid secretory response with entrapped electrolytes was profound in ARF rats. Histopathological analysis of CT exposed tissues revealed that apart from the tissue damage produced by acute renal failure, no CT induced cellular changes occurred. Conclusion: CT can be used as a secretagogue to induce fluid and electrolyte secretion in ARF rats. However, effective measures should be taken to avoid CT induced acidosis.

Background: Androctonus mauretanicus (Am) is one of the most hazardous scorpions in Morocco and has a highly toxic venom responsible for severe cases of envenomation. However, few studies have focused on decifering its proteic composition. Objectives: Herein, we aim to map out the complete proteome of the Am venom in order to highlight its complexity and the polymorphism of its toxic content. This, in turn, will lead to a deeper understanding of the toxins’ mechanism of action and will help uncover those with therapeutic potential. Methods: Top-down and bottom-up proteomic approaches were used complementarily to decipher the proteome of the Am venom. These approaches were carried out on nano-high liquid chromatography coupled to nano-electrospray tandem mass spectrometry (Nano-LC-ESI-MS/MS). Results: Am venom encloses a complex mixture of 269 different compounds with molecular weights ranging from 1618.74 to 14 214.84 Da. The most abundant ones showed masses from 6185.92 to 7899.53 Da (53.89%) followed by those ranging from 2079.25 to 5969.63 Da (37.81%). Interestingly, the combination of the results of both approaches allowed the screening of a total of 112 peptides. The highest percentage was represented by neuropeptides (87%), including NaTxs, KTxs, ClTxs, venom proteins, venom neuropeptides, and myotropic neuropeptides. Moreover, other peptides were identified, such as antimicrobial peptides, amphipathic peptides, cysteine-rich venom peptides, enzymes, kunitz-type inhibitor and orphan peptides. Conclusion: The Am venom appears to contain a great amount of diverse peptides, some of which could prospectively be exploited for their pharmaceutical potential.

Abstract: Phospholipases A2 enzymes are found in many mammalian tissues and in animal venoms. Those present in bee venom (bvPLA2) and snake venom (svPLA2) have been studied more particularly for their biological activities of interest. Although they belong to the same family of secreted PLA2 (sPLA2), bvPLA2 and svPLA2 differ from a structural and functional point of view. In this review, we describe the morphological characteristics of these two enzymes and the structural determinants that govern their functions. After describing their cytotoxicity, we compared their biological activities, including antimicrobial, anti-tumor, anti-inflammatory, anti-neurodegenerative, and anti-nociceptive effects. In addition, we highlighted their therapeutical applications and deduced bvPLA2 has better potential than svPLA2 in biotechnological and pharmaceutical innovations.