ABSTRACT
Current treatment of snakebite relies on immunoglobulin-rich antivenoms. However, production of these antivenoms is complicated and costly. Aptamers - single-stranded DNAs or RNAs with specific folding structures that bind to specific target molecules - represent excellent alternatives or complements to antibody-based therapeutics. However, no studies have systematically assessed the feasibility of using aptamers to mitigate venom-induced toxicity in vivo. ß-bungarotoxin is the predominant protein responsible for the toxicity of the venom of Bungarus multicinctus, a prominent venomous snake inhabiting Taiwan. In this study, we reported the screening and optimization of a DNA aptamer against ß-bungarotoxin and tested its utility in a mouse model. After 14 rounds of directed evolution of ligands by exponential enrichment, an aptamer, called BB3, displaying remarkable binding affinity and specificity for ß-bungarotoxin was obtained. Following structural prediction and point-modification experiments, BB3 underwent truncation and was modified with 2'-O-methylation and a 3'-inverted dT. This optimized aptamer showed sustained, high-affinity binding for ß-bungarotoxin and exhibited remarkable nuclease resistance in plasma. Importantly, administration of this optimized aptamer extended the survival time of mice treated with a lethal dose of ß-bungarotoxin. Collectively, our data provide a compelling illustration of the potential of aptamers as promising candidates for development of recombinant antivenom therapies.
Subject(s)
Aptamers, Nucleotide , Bungarotoxins , Animals , Aptamers, Nucleotide/pharmacology , Aptamers, Nucleotide/chemistry , Bungarotoxins/pharmacology , Bungarotoxins/chemistry , Mice , Disease Models, Animal , Bungarus , Snake Bites/drug therapy , SELEX Aptamer TechniqueABSTRACT
Animal testing has been the primary approach to assess the neutralization potency of antivenom for decades. However, the necessity to sacrifice large numbers of experimental animals during this process has recently raised substantial welfare concerns. Furthermore, the laborious and expensive nature of animal testing highlights the critical need to develop alternative in vitro assays. Here, we developed an antibody-detection enzyme-linked immunosorbent assay (ELISA) technique as an alternative approach to evaluate the neutralization potency of hyperimmunized equine plasma against B. multicinctus, a medically important venomous snake in Taiwan. Firstly, five major protein components of B. multicinctus venom, specifically, α-BTX, ß-BTX, γ-BTX, MTX, and NTL, were isolated. To rank their relative medical significance, a toxicity score system was utilized. Among the proteins tested, ß-BTX presenting the highest score was regarded as the major toxic component. Subsequently, antibody-detection ELISA was established based on the five major proteins and used to evaluate 55 hyperimmunized equine plasma samples with known neutralization potency. ELISA based on ß-BTX, the most lethal protein according to the toxicity score, exhibited the best sensitivity (75.6 %) and specificity (100 %) in discriminating between high-potency and low-potency plasma, supporting the hypothesis that highly toxic proteins offer better discriminatory power for potency evaluation. Additionally, a phospholipase A2 (PLA2) competition process was implemented to eliminate the antibodies targeting toxicologically irrelevant domains. This optimization greatly enhanced the performance of our assay, resulting in sensitivity of 97.6 % and specificity of 92.9 %. The newly developed antibody-detection ELISA presents a promising alternative to in vivo assays to determine the neutralization potency of antisera against B. multicinctus during the process of antivenom production.
Subject(s)
Bungarotoxins , Bungarus , Animals , Horses , Bungarus/metabolism , Bungarus multicinctus , Antivenins , Taiwan , Enzyme-Linked Immunosorbent AssayABSTRACT
Bungarus Parvus, a precious animal Chinese medicinal material used in clinical practice, is believed to be first recorded in Ying Pian Xin Can published in 1936. This study was carried out to analyze the names, geographical distribution, morphological characteristics, ecological habits, poisonousness, and medicinal parts by consulting ancient Chinese medical books and local chronicles, Chinese Pharmacopeia, different processing standards of trditional Chinese medicine(TCM) decoction pieces, and modern literatures. The results showed that the earliest medicinal record of Bungarus Parvus was traced to 1894. In 1930, this medicinal material was used in the formulation of Annao Pills. The original animal, Bungarus multicinctus, was recorded by the name of "Bojijia" in 1521. The morphological characteristics, ecological habits, and poisonousness of the original animal are the same in ancient and modern records. The geographical distribution is similar between the ancient records and modern documents such as China Medicinal Animal Fauna. The dried body of young B. multicinctus is used as Bungarus Parvus, which lack detailed references. As a matter of fact, it is still inconclusive whether there are differences between young snakes and adult snakes in terms of active ingredients, pharmacological effects, and clinical applications. This study clarified the medicinal history and present situation of Bungarus Parvus. On the basis of the results, it is suggested that systematic comparison on young and adult B. multicinctus should be carried out to provide references for revising the medicinal parts of B. multicinctus.
Subject(s)
Bungarus , Drugs, Chinese Herbal , Animals , Snakes , China , Medicine, Chinese TraditionalABSTRACT
Modern analytical size exclusion chromatography (SEC) is a suitable technique to separate venom toxin families according to their size characteristics. In this study, a method was developed to separate intact venom toxins from Bungarus multicinctus and Daboia russelii venoms via analytical SEC using volatile, non-salt-containing eluents for post-column mass spectrometry, coagulation bioassaying and high-throughput venomics. Two venoms were used to demonstrate the method developed. While the venom of Bungaurs multicinctus is known to exert anticoagulant effects on plasma, in this study, we showed the existence of both procoagulant toxins and anticoagulant toxins. For Daboia russelii venom, the method revealed characteristic procoagulant effects, with a 90 kDa mass toxin detected and matched with the Factor X-activating procoagulant heterotrimeric glycoprotein named RVV-X. The strong procoagulant effects for this toxin show that it was most likely eluted from size exclusion chromatography non-denatured. In conclusion, the separation of snake venom by size gave the opportunity to separate some specific toxin families from each other non-denatured, test these for functional bioactivities, detect the eluting mass on-line via mass spectrometry and identify the eluted toxins using high-throughput venomics.
Subject(s)
Anticoagulants , Biological Assay , Chromatography, Gel , Mass Spectrometry , Viper VenomsABSTRACT
Background: Bungarus multicinctus is one of the most dangerous venomous snakes prone to cardiopulmonary damage with extremely high mortality. In our previous work, we found that glutamine (Gln) and glutamine synthetase (GS) in pig serum were significantly reduced after Bungarus multicinctus bite. In the present study, to explore whether there is a link between the pathogenesis of cardiopulmonary injury and Gln metabolic changes induced by Bungarus multicinctus venom. We investigated the effect of Gln supplementation on the lung and heart function after snakebite. Methods: We supplemented different concentrations of Gln to mice that were envenomated by Bungarus multicinctus to observe the biological behavior, survival rate, hematological and pathological changes. Gln was supplemented immediately or one hour after the venom injection, and then changes in Gln metabolism were analyzed. Subsequently, to further explore the protective mechanism of glutamine on tissue damage, we measured the expression of heat-shock protein70 (HSP70), NF-κB P65, P53/PUMA by western blotting and real-time polymerase in the lung and heart. Results: Gln supplementation delayed the envenoming symptoms, reduced mortality, and alleviated the histopathological changes in the heart and lung of mice bitten by Bungarus multicinctus. Additionally, Gln increased the activity of glutamine synthetase (GS), glutamate dehydrogenase (GDH) and glutaminase (GLS) in serum. It also balanced the transporter SLC7A11 expression in heart and lung tissues. Bungarus multicinctus venom induced the NF-κB nuclear translocation in the lung, while the HO-1 expression was suppressed. At the same time, venom activated the P53/PUMA signaling pathway and the BAX expression in the heart. Gln treatment reversed the above phenomenon and increased HSP70 expression. Conclusion: Gln alleviated the glutamine metabolism disorder and cardiopulmonary damage caused by Bungarus multicinctus venom. It may protect lungs and heart against venom by promoting the expression of HSP70, inhibiting the activation of NF-κB and P53/PUMA, thereby delaying the process of snake venom and reducing mortality. The present results indicate that Gln could be a potential treatment for Bungarus multicinctus bite.
ABSTRACT
Bungarus multicinctus (B. multicinctus) is one of the top ten venomous snakes in China, ranking first in lethality at 26.9-33.3%. However, to our knowledge, no forensic autopsy-related cases of death from B. multicinctus bite poisoning have been reported. There are surprisingly few reported cases of death from poisoning by other species of neurotoxic snakes. Neurotoxic snake venom is often highly toxic, and death can quickly occur when bitten in the wild if victims are not taken to a doctor in time. We presented a case of an adult female in Fujian Province of China who was bitten by a poisonous snake while digging for bamboo shoots in the mountains and died from the bite of B. multicinctus confirmed by enzyme-linked immunosorbent assays (ELISA) results. The autopsy's results, histopathological findings, and ELISA results reported here can be helpful for future forensic practice in B. multicinctus venom poisoning; we also briefly review the pathological changes of neurotoxin poisoning, which may be useful in other types of neurotoxin snake venom poisoning.
Subject(s)
Bungarus , Snake Bites , Humans , Adult , Animals , Female , Neurotoxins , Forensic Medicine , AutopsyABSTRACT
Bungarus multicinctus is a widely distributed and medically important elapid snake that produces lethal neurotoxic venom. To study and enhance existing antivenom, we explore the complete repertoire of its toxin genes based on de novo chromosome-level assembly and multi-tissue transcriptome data. Comparative genomic analyses suggest that the three-finger toxin family (3FTX) may evolve through the neofunctionalization of flanking LY6E. A long-neglected 3FTX subfamily (i.e., MKA-3FTX) is also investigated. Only one MKA-3FTX gene, which evolves a different protein conformation, is under positive selection and actively transcribed in the venom gland, functioning as a major toxin effector together with MKT-3FTX subfamily homologs. Furthermore, this lethal snake may acquire self-resistance to its ß-bungarotoxin via amino acid replacements on fast-evolving KCNA2. This study provides valuable resources for further evolutionary and structure-function studies of snake toxins, which are fundamental for the development of effective antivenoms and drug candidates.
Subject(s)
Elapid Venoms , Elapidae , Animals , Antivenins/chemistry , Antivenins/metabolism , Bungarus/metabolism , Elapid Venoms/chemistry , Elapid Venoms/metabolism , Elapid Venoms/toxicity , Elapidae/genetics , Elapidae/metabolism , Three Finger ToxinsABSTRACT
BACKGROUND: Bungarus multicinctus, from which a classical Chinese medicine is produced, is known as the most venomous land snake in the world, but the chromatin organization and transcription factor activity during venom replenishment progress have not been explored yet. This study aimed to determine the roles of chromatin structure in toxin activity via bioinformatics and experimental validation. METHODS: Chromosome conformation capture (Hi-C) analysis was used to examine interactions among chromosomes and identify different scales of chromatin during envenomation in B. multicinctus. Correlations between epigenetic modifications and chromatin structure were verified through ChIP-seq analysis. RNA-seq was used to validate the influence of variation in chromatin structure and gene expression levels on venom production and regulation. RESULTS: Our results suggested that intra-chromosomal interactions are more intense than inter-chromosomal interactions among the control group, 3-day group of venom glands and muscles. Through this, we found that compartmental transition was correlated with chromatin interactions. Interestingly, the up-regulated genes in more compartmental switch regions reflect the function of toxin activity. Topologically associated domain (TAD) boundaries enriched with histone modifications are associated with different distributions of genes and the expression levels. Toxin-coding genes in the same loop are highly expressed, implying that the importance of epigenetic regulation during envenomination. On a smaller scale, the epigenetic markers affect transcriptional regulation by controlling the recruitment/inhibition of transcription initiation complexes. CONCLUSIONS: Chromatin structure and epigenetic modifications could play a vital status role in the mechanisms of venom regulation in B. multicinctus.
ABSTRACT
Bungarus multicinctus is one of the top ten venomous snakes in China, and its bite causes acute and severe diseases, but its pathophysiology remains poorly elucidated. Thus, an animal model of Bungarus multicinctus bite was established by intramuscular injection of 30µg/kg of Bungarus multicinctus venom, and then the serum metabolites were subsequently screened, identified and validated by ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS) methods to explore the potential biomakers and possible metabolic pathways. Untargeted metabolomics analysis showed that 36 and 38 endogenous metabolites levels changed in ESI+ and ESI-, respectively, KEGG pathway analysis showed that 5 metabolic pathways, including mineral absorption, central carbon metabolism in cancer, protein digestion and absorption, aminoacyl-tRNA biosynthesis and ABC transporters might be closely related to Bungarus multicinctus bite. Targeted metabolomics analysis showed that there were significant differences in serum D-proline, L-leucine and L-glutamine after Bungarus multicinctus bite (P < 0.05). In addition, receiver operating characteristic (ROC) analysis showed that the diagnostic efficiency of L-Glutamine was superior to other potential biomarkers and the AUC value was 0.944. Moreover, we found evidence for differences in the pathophysiology of glutamine between Bungarus multicinctus bite group and normal group, specifically with the content of glutamine synthetase (GS) and glutaminase (GLS). Taken together, the current study has successfully established an animal model of Bungarus multicinctus bite, and further identified the links between the metabolic perturbations and the pathophysiology and the potential diagnostic biomakers of Bungarus multicinctus bite, which provided valuable insights for studying the mechanism of Bungarus multicinctus bite.
Subject(s)
Bungarus , Elapid Venoms/blood , Elapid Venoms/metabolism , Elapid Venoms/toxicity , Metabolic Networks and Pathways/drug effects , Metabolomics , Swine, Miniature/blood , Animals , China , Female , Male , Mice , Models, Animal , SwineABSTRACT
La intoxicación por mordedura de serpiente es un problema de salud pública global. En la población pediátrica, la intoxicación por mordedura de serpiente presenta características diferentes que en los pacientes adultos. La Bungarus multicinctus es una especie de elápido sumamente venenoso. Las presentaciones clínicas documentadas después de la intoxicación por mordedura de Bungarus multicinctus son reacciones locales mínimas, insuficiencia respiratoria, dolor generalizado e hiponatremia potencialmente mortal. Presentamos el caso de una intoxicación por mordedura de Bungarus multicinctus en una niña con manifestaciones clínicas atípicas, incluidas necrosis tisular grave y trombocitopenia con coagulopatía.
Snakebite envenoming is a global public health problem. The pediatric population poisoned by snakebite envenoming has different features than adult patients. Bungarus multicinctus is a highly venomous species of the elapid snake. The documented clinical presentations following Bungarus multicinctus envenoming are minimal local reactions, respiratory failure, general pain, and life-threatening hyponatremia. We present an uncommon case of Bungarus multicinctus envenomation in a girl with unusual clinical findings, including severe tissue necrosis and thrombocytopenia with coagulopathy.
Subject(s)
Humans , Female , Child , Snake Bites , Necrosis , Poisoning , Thrombocytopenia , Blood Coagulation Disorders , China , BungarusABSTRACT
Snakebite envenoming is a global public health problem. The pediatric population poisoned by snakebite envenoming has different features than adult patients. Bungarus multicinctus is a highly venomous species of the elapid snake. The documented clinical presentations following Bungarus multicinctus envenoming are minimal local reactions, respiratory failure, general pain, and life-threatening hyponatremia. We present an uncommon case of Bungarus multicinctus envenomation in a girl with unusual clinical findings, including severe tissue necrosis and thrombocytopenia with coagulopathy.
La intoxicación por mordedura de serpiente es un problema de salud pública global. En la población pediátrica, la intoxicación por mordedura de serpiente presenta características diferentes que en los pacientes adultos. La Bungarus multicinctus es una especie de elápido sumamente venenoso. Las presentaciones clínicas documentadas después de la intoxicación por mordedura de Bungarus multicinctus son reacciones locales mínimas, insuficiencia respiratoria, dolor generalizado e hiponatremia potencialmente mortal. Presentamos el caso de una intoxicación por mordedura de Bungarus multicinctus en una niña con manifestaciones clínicas atípicas, incluidas necrosis tisular grave y trombocitopenia con coagulopatía.
Subject(s)
Respiratory Insufficiency , Snake Bites , Thrombocytopenia , Adult , Animals , Antivenins/therapeutic use , Bungarus , Child , Female , Humans , Necrosis/etiology , Snake Bites/complicationsABSTRACT
Bungarus multicinctus, the Chinese krait, is a highly venomous elapid snake which causes considerable morbidity and mortality in southern China. B. multicinctus venom contains pre-synaptic PLA2 neurotoxins (i.e., ß-bungarotoxins) and post-synaptic neurotoxins (i.e., α-bungarotoxins). We examined the in vitro neurotoxicity of B. multicinctus venom, and the efficacy of specific monovalent Chinese B. multicinctus antivenom, and Australian polyvalent elapid snake antivenom, against venom-induced neurotoxicity. B. multicinctus venom (1-10 µg/mL) abolished indirect twitches in the chick biventer cervicis nerve-muscle preparation as well as attenuating contractile responses to exogenous ACh and CCh, but not KCl. This indicates a post-synaptic neurotoxic action but myotoxicity was not evident. Given that post-synaptic α-neurotoxins have a more rapid onset than pre-synaptic neurotoxins, the activity of the latter in the whole venom will be masked. The prior addition of Chinese B. multicinctus antivenom (12 U/mL) or Australian polyvalent snake antivenom (15 U/mL), markedly attenuated the neurotoxic actions of B. multicinctus venom (3 µg/mL) and prevented the inhibition of contractile responses to ACh and CCh. The addition of B. multicinctus antivenom (60 U/mL), or Australian polyvalent snake antivenom (50 U/mL), at the t90 time point after the addition of B. multicinctus venom (3 µg/mL), did not restore the twitch height over 180 min. The earlier addition of B. multicinctus antivenom (60 U/mL), at the t20 or t50 time points, also failed to prevent the neurotoxic effects of the venom but did delay the time to abolish twitches based on a comparison of t90 values. Repeated washing of the preparation with physiological salt solution, commencing at the t20 time point, failed to reverse the neurotoxic effects of venom or delay the time to abolish twitches. This study showed that B. multicinctus venom displays marked in vitro neurotoxicity in a skeletal muscle preparation which is not reversed by antivenom. This does not appear to be related to antivenom efficacy, but due to the irreversible/pseudo-irreversible nature of the neurotoxins.
Subject(s)
Antivenins/pharmacology , Bungarotoxins/toxicity , Bungarus , Elapid Venoms/toxicity , Neurotoxins/toxicity , Acetylcholine/metabolism , Animals , Carbachol/metabolism , Chickens , China , In Vitro Techniques , Muscle Contraction/drug effects , Muscle, Skeletal/drug effects , Neuromuscular Junction/drug effects , Time FactorsABSTRACT
Bungarus multicinctus, an important traditional Chinese medicine, possesses remarkable medicinal activities, while lots of adulterants from other species were misused as B. multicinctus for its large demand and resource starvation. In order to accurately identify B. multicinctus and its common adulterants such as Sinonatrix annularis, Xenochrophis flavipunctatus, Deinagkistrodon acutus, and Naja atra, a simultaneous identification method was designed with multiplex ligation-dependent probe amplification (MLPA) analysis. Five species-specific MLPA probe-couples for B. multicinctus and its common adulterants were designed based on the universal primer amplified COI sequences, which can specifically detect the five species with no mutual interference, and sensitivity analysis showed as less as 5% B. multicinctus or 8.75% adulterants in the mixed samples can be identified in a MLPA assay, especially, the relative quantity of the adulterants can be also inferred based on the MLPA peak area values. Moreover, the results of the present study confirmed the effectiveness of this technique in terms of simultaneous identification of B. multicinctus and its common adulterants in an assay, which has great potential for ensuring the safety of this commercially valuable snake species.
ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Bungarus multicinctus snake belongs to Elapidae family and is widely distributed in southern China. It is widely used in traditional Chinese medicine with the effect of dispelling wind and removing obstruction in the meridians. Moreover, it is also as a chief ingredient of many polyherbal formulations for the treatment of cancer. AIM OF THE STUDY: To evaluate the antitumor activity of Bungarus multicinctus snake venom components and isolate, characterize the most effective anti-tumor component of Bungarus multicinctus snake venom. MATERIALS AND METHODS: The in vitro antitumor activity of Bungarus multicinctus venom components was detected by cytotoxicity assay and cell apoptosis assay. A unique LAAO from Bungarus multicinctus venom named as BM-Apotxin was isolated and characterized by Sephadex G-75 gel filtration, Sephadex G-25 desalting, Q ion-exchange chromatography and subsequent amino acids sequence determination. The LAAO activity and enzyme kinetics of BM-Apotxin was detected by microplate assay. RESULTS: BM-Apotxin, a 65KDa glycoprotein, which contributed to the most anti-tumor effects of Bungarus multicinctus venom. BM-Apotxin can selectively kill tumor cells, with less cytotoxicity to the normal cells. BM-Apotxin is an L-amino acid oxidase (LAAO) with high sequence identity to other snake venom LAAOs. Its anti-tumor activity is mainly due to the hydrogen peroxide produced from LAAO oxidation. But the catalase did not reverse its anti-tumor effect completely. Like other snake venom LAAOs, BM-Apotxin can oxidize many L amino acids, not D amino acids. The optimum substrate for BM-Apotxin is L-Phe. Moreover, BM-Apotxin deglycosylation can significantly reduce the LAAO activity and anti-tumor activity of BM-Apotxin. CONCLUSION: This study will facilitate the study on anti-tumor mechanism of snake venom and drug development based on Bungarus multicinctus venom.
Subject(s)
Bungarus , Elapid Venoms/pharmacology , L-Amino Acid Oxidase/isolation & purification , L-Amino Acid Oxidase/pharmacology , Amino Acid Sequence , Animals , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Elapid Venoms/chemistry , Humans , L-Amino Acid Oxidase/chemistryABSTRACT
Bungarus multicinctus (many-banded krait) and Naja atra (Chinese cobra) are widely distributed and medically important venomous snakes in China; however, their venom proteomic profiles have not been fully compared. Here, we fractionated crude venoms and analyzed them using a combination of proteomic techniques. Three-finger toxins (3-FTx) and phospholipase A2 (PLA2) were most abundant in both species, respectively accounting for 32.6% and 66.4% of total B. multicinctus venom, and 84.3% and 12.2% of total N. atra venom. Venoms from these two species contained one common protein family and six less abundant species-specific protein families. The proteomic profiles of B. multicinctus and N. atra venoms and analysis of toxicological activity in mice suggested that 3-FTx and PLA2 are the major contributors to clinical symptoms caused by envenomation. The venoms differed in enzymatic activity, likely the result of inter-specific variation in the amount of related venom components. Antivenomics assessment revealed that a small number of venom components (3-FTxs and PLA2s in B. multicinctus, and 3-FTxs in N. atra) could not be immunocaptured completely, suggesting that we should pay attention to enhancing the immune response of these components in designing commercial antivenoms for B. multicinctus and N. atra. BIOLOGICAL SIGNIFICANCE: The proteomic profiles of venoms from two medically important snake species - B. multicinctus and N. atra - have been explored. Quantitative and qualitative differences are evident in both venoms when proteomic profiles and transcriptomic results are compared; this is a reminder that combined approaches are needed to explore the precise composition of snake venom. Two protein families (3-FTx and PLA2) of high abundance in these snake venoms are major players in the biochemical and pharmacological effects of envenomation. Elucidation of the proteomic profiles of these snake venoms is helpful in understanding composition-function relationships and will facilitate the clinical application of antivenoms.
Subject(s)
Bungarotoxins , Bungarus/metabolism , Elapid Venoms , Elapidae/metabolism , Proteomics , Animals , Bungarotoxins/chemistry , Bungarotoxins/metabolism , Elapid Venoms/chemistry , Elapid Venoms/metabolism , Mice , Species SpecificityABSTRACT
Kraits are venomous snakes of genus Bungarus from family Elapidae. Krait venoms are generally neurotoxic, but toxicity strongly depends on the particular species and regional origin of snakes. We analyzed the proteomes of Vietnamese Bungarus multicinctus and Bungarus fasciatus venoms both qualitatively and quantitatively. It should be noted that no proteomic data for B. multicinctus venom existed so far. We have found that in this venom, almost half (45%) of the proteins by weight was represented by ß-bungarotoxins, followed by three finger toxins (28%) and phospholipases A2 (16%), other proteins being present at the level of 1-3%. In B. fasciatus venom, phospholipase A2 was the main component (71%), followed by oxidase of l-amino acids (8%), acetylcholinesterase (5%) and metalloproteinases (4%). Unexpectedly, extremely low amount of three finger toxins (1%) was found in this venom. Interestingly, the presence of complement depleting factor was observed in both venoms. Although our data showed the presence of the same toxin families in Vietnamese krait venoms as those found earlier in the venoms of kraits from other geographic regions, their relative ratio is completely different. This concerns especially B. fasciatus venom with predominant content of phospholipases A2 and very low amount of three finger toxins.
Subject(s)
Bungarus , Elapid Venoms/chemistry , Neurotoxins/chemistry , Phospholipases A2/chemistry , Reptilian Proteins/chemistry , Animals , Chromatography, Liquid , Expressed Sequence Tags , Mass Spectrometry , Neurotoxins/analysis , Phospholipases A2/analysis , Proteomics , Reptilian Proteins/analysisABSTRACT
OBJECTIVE: To test the feasibility of DNA barcoding for accurate identification of Jinqian Baihua She and its adulterants. MATERIALS AND METHODS: Standard cytochrome C oxidase subunit I (COI) gene fragments were sequenced for DNA barcoding of 39 samples from 9 snake species, including Bungarus multicinctus, the officially recognized origin animal by Chinese Pharmacopoeia, and other 8 adulterate species. The aligned sequences, 658 base pairs in length, were analyzed for divergence using the Kimura-2-parameter (K2P) distance model with MEGA5.0. RESULTS: The mean intraspecific K2P distance was 0.0103 and the average interspecific genetic distance was 0.2178 in B. multicinctus, far greater than the minimal interspecific genetic distance of 0.027 recommended for species identification. A neighbor-joining (NJ) tree was constructed, in which each species formed a monophyletic clade with bootstrap supports of 100%. All the data were submitted to Barcode of Life Data system version 3.0 (BOLD, http://www.barcodinglife.org) under the project title "DNA barcoding Bungarus multicinctus and its adulterants". Ten samples of commercially available crude drugs of JBS were identified using the identification engine provided by BOLD. All the samples were clearly identified at the species level, among which five were found to be the adulterants and identified as Dinodon rufozonatum. CONCLUSION: DNA barcoding using the standard COI gene fragments provides an effective and accurate means for JBS identification and authentication.