湖南烙铁头蛇毒蛋白组分的双向电泳分析

烙铁头蛇是世界上剧毒的蛇种之一,其所携带的毒素能够导致严重的机体损伤。应用蛋白质双向电泳技术,对湖南烙铁头蛇蛇毒蛋白的蛋白质组分进行分析。通过等电聚焦和SDS-PAGE凝胶电泳分析获得完整的烙铁头蛇毒全蛋白质的图谱,经胶体考马斯亮蓝染色后,应用PDQuest软件对蛋白表达谱进行分析。通过等电聚焦和SDS-PAGE凝胶电泳有83个蛋白质组分被检测出来。其中大约90.00%的蛋白质的相对分子质量(Mr)分布在15～45 kDa之间,大约72.29%的蛋白质等电点(pI)在4.0～7.0之间。通过对烙铁头蛇毒的蛋白组学研究,获得其蛇毒蛋白质组分的表征特点,为后续进一步研究各组分的身份和潜在功能奠定基础,既可以提出新的治疗方案又可以为新的药理应用提供宝贵资源。     

莽山烙铁头蛇的养殖现状及存在问题

莽山烙铁头蛇分布范围狭窄,种群数量稀少,只在中国湘粤边界一带有分布,是中国特有的濒危蛇种。1994年列入《中国生物多样性保护行动计划》一级优先保护动物;1998年列入《中国濒危动物红皮书》极危等级的生物种;多次列入IUCN红色保护名录。开展对莽山烙铁头蛇的人工繁殖研究,扩大其种群数量,是保护好这一珍稀物种的唯一和关键的措施。我们从1994年起就开展了对莽山烙铁头蛇的人工繁殖和养殖研究,并成功繁殖100条莽山烙铁头幼蛇。在养殖莽山烙铁头蛇的过程中,我们发现有食物链狭窄、繁殖率低下、种群内亲杀、疾病与寄生虫等几种因素,严重影响莽山烙铁头蛇的成活率,这些因素的存在严重威胁着这个种群的生存。     

莽山烙铁头蛇专项Ermia mangshanensis(Zhao,1990)调查结果

1998～ 2 0 0 0年 ,在莽山地区对莽山烙铁头蛇的分布、种群数量等进行了专项调查。调查结果表明莽山烙铁头蛇确实是一种数量稀少、分布范围狭窄的蛇类 ,已经处于极度濒危程度 ,建议尽快将其列为国家一级重点保护动物。     

中国独特生物,蛇中“大熊猫”——莽山烙铁头蛇研究与保护剪影

莽山烙铁头蛇是一种巨型毒蛇,也是我国独有的珍稀濒危蛇种,该蛇在蛇类演化中有着极其特殊的地位,有着无与伦比的生态价值和极高的学术研究价值。由于该蛇极其罕见珍贵,黑市价格从每条数百元暴涨至百万元,因此,有蛇中“大熊猫”之称的莽山烙铁头蛇再次引起人们的极大关注,对莽山烙铁头蛇采取抢救性的保护工作已刻不容缓。     

莽山烙铁头蛇的濒危现状与保护对策

目的探讨我国特有的珍稀蛇种──莽山烙铁头蛇的濒危现状与保护对策。方法基于文献资料,结合作者近年来的调查工作,对莽山烙铁头蛇的分布区、种群数量、濒危现状与威胁因素进行分析和探讨。结果近10年来,莽山烙铁头蛇的种群数量没有明显增加,基本保持稳定,但是仍遭受猎捕、贸易及栖息地破坏等因素的威胁。结论要保护好我国这一特有的珍稀蛇种,需要尽快将莽山烙铁头蛇列入国家重点保护野生动物名单,列入《濒危野生动植物种国际贸易公约》,加强法律保护力度及国际贸易管控,积极开展生态生物学研究,实施人工繁殖和放归野外计划,以促进野生种群复壮。     

莽山烙铁头蛇Ermiamangshanensis(Zhao,1990)专项调查结果

1998－2000年,在莽山地区对莽山烙铁头蛇的分布、种群数量等进行了专项调查。调查结果表明莽山烙铁头蛇确实是一种数量稀少、分布范围狭窄的蛇类,已经处于极度濒危程度,建议尽快将其列为国家一级重点保护动物。     

乌梢蛇血清对白眉蝮等3种蛇毒解毒作用初探

目的 探讨乌梢蛇血清对孟加拉眼镜蛇、白眉蝮、莽山烙铁头3种毒蛇的解毒作用。方法 给18～22g昆明小鼠分别注射盂加拉眼镜蛇毒、白眉蝮蛇毒及莽山烙铁头蛇毒后,随机分组注射不同浓度的乌梢蛇血清,并观察对3种蛇毒的解毒效果。结果 发现（1）乌梢蛇血清对盂加拉眼镜蛇毒有解毒作用．且注射蛇毒与4ml／kg的血清混合液的解毒作用最好,但随着间隔时间的延长,解毒作用逐渐减弱;（2）乌梢蛇血清对白眉蝮蛇毒有解毒作用,且注射量为1ml／kg和2ml／kg时出现了拮抗作用;（3）乌梢蛇血清对莽山烙铁头蛇毒有解毒作用,但莽山烙铁头蛇毒对血清注射量和间隔时间不敏感,在血清注射量为2ml／kg时和注射蛇毒10min后,再注射4ml／kg的血清时出现了拮抗作用。（4）只给小鼠注射不同量的乌梢蛇血清,发现乌梢蛇血清对小鼠无明显的毒副作用。结论 乌梢蛇血清对3种蛇毒均有解毒作用。     

MSCT在莽山烙铁头研究中的应用

利用多层螺旋计算机断层摄影(MSCT)扫描莽山烙铁头(Trimeresurus mangshanensis),通过重建显示蛇的各部分解剖结构,来探讨MSCT在保护濒危动物莽山烙铁头的应用价值。对3条莽山烙铁头进行CT扫描,扫描完毕重建出蛇的二维、三维图像,并分别显示其体表、骨骼、内脏等细节,MSCT能够对蛇的解剖、生境状况、疾病的诊断等方面进行研究和评价,也为蛇类等动物的研究提供新思路和新方法。     

一种新的烙铁头蛇毒肌肉毒素

用分子筛和快速蛋白质液相色谱从烙铁头（ＴＲｒｉｍｅｒｅｓｕｒｕｓ ｍｕｃｒｏｓｑｕａｍａｔｕｓ）蛇毒中分离了一个新的碱性肌肉毒素,命名为ＴＭＰＢ。它的分子量为１６０００,等电点为９．２．用蛋白质序列仪测定了其Ｎ端２４个氨基酸残基,ＴＭＰＢ与其他两个从同种蛇毒中分离到的碱性磷酯酶Ａ２的同源性分别为４１．７％和５４．２％《     

2008中国首届莽山烙铁头蛇保护工程研讨会议纪要

中国首届莽山烙铁头蛇保护工程研讨会于2008年5月21日～26日在湖南郴州莽山国家森林公园内召开。会议由郴州市及宜章县人民政府主办,莽山国家森林公园承办。     

Snake venomics and antivenomics of Protobothrops mucrosquamatus and Viridovipera stejnegeri from Taiwan: Keys to understand the variable immune response in horses

The proteomes of the venoms of the snakes Viridovipera stejnegeri and Protobothrops mucrosquamatus from Taiwan were characterized by N-terminal sequencing, MALDI-TOF mass fingerprinting, and collision-induced dissociation tandem mass spectrometry of in-gel generated tryptic peptides. Proteins belonging to the following toxin classes were identified: metalloproteinase, phospholipase A(2) (PLA(2)), serine proteinase, C-type lectin-like, CRISP, l-amino acid oxidase, disintegrin, and peptides (vasoactive and inhibitors of SVMPs). Nine horses were immunized with a mixture of these venoms. All horses developed a satisfactory immune response against lethality of the venom of V. stejnegeri, whereas only three horses reached the accepted neutralizing potency against the venom of P. mucrosquamatus. Antivenoms were prepared from pools of 'good responder' (GR) and 'poor responder' (PR) horses and compared by antivenomics and neutralization tests. A similar neutralizing response was observed between the GR and PR antivenoms against the venom of V. stejnegeri, whereas antivenom from PR had a lower neutralizing activity against effects of P. mucrosquamatus venom than antivenom from GR. The low potency of the plasma of some horses against this venom is a consequence of the low immunogenicity of the neurotoxic PLA(2) trimucrotoxin. Our results provide clues for innovating the immunization scheme to generate improved antivenoms.     

Venomic analysis and evaluation of antivenom cross-reactivity of South American Micrurus species

Coral snakes from Micrurus genus are the main representatives of the Elapidae family in South America. However, biochemical and pharmacological features regarding their venom constituents remain poorly investigated. Here, venomic analyses were carried out aiming at a deeper understanding on the composition of M. frontalis, M. ibiboboca, and M. lemniscatus venoms. In the three venoms investigated, proteins ranging from 6 to 8 kDa (3FTx) and 12 to 14 kDa (PLA(2)) were found to be the most abundant. Also, the N-terminal sequences of four new proteins, purified from the M. lemniscatus venom, similar to 3FTx, PLA(2) and Kunitz-type protease inhibitor from other Micrurus and elapid venoms are reported. Cross-reactivity among different Micrurus venoms and homologous or heterologous antivenoms was carried out by means of 2D-electrophoresis and immunoblotting. As, expected, the heterologous anti-Elapid venom displayed the highest degree of cross-reactivity. Conversely, anti-M. corallinus reacted weakly against the tested venoms. In gel digestions, followed by mass spectrometry sequencing and similarity searching, revealed the most immunogenic protein families as similar to short and long neurotoxins, weak neurotoxins, PLA(2), β-bungarotoxin, venom protein E2, frontoxin III, LAO and C-type lectin. The implications of our results for the production of Micrurus antivenoms are discussed.     

乌梢蛇血清的抗出血因子:一个有前途的抗蛇毒药物原料

用柱层析和聚丙烯酰胺凝胶盘状电泳法,从乌梢蛇血清中分离纯化了一个抗出血因子。用SDS-聚丙烯酰胺凝胶电泳法测得其分子量大约为65 kD;测定了五种蝮亚科蛇毒(尖吻蝮、竹叶青蛇、原矛头蝮、哈扑和短尾蝮)的最小出血剂量和乌梢蛇血清中抗出血因子对这五种蛇毒的抗出血活性;还测定了七种蛇毒(除上述五种毒蛇外,还包括圆斑蝰和银环蛇)的半数致死量,以及抗出血因子对中毒小鼠的治疗作用。结果显示:从乌梢蛇血清中提纯的抗出血因子的抗蛇毒活性,不仅可以抵抗它的捕食者尖吻蝮的蛇毒,而且还可以抵抗具出血活性的其它蛇毒;但它对不具出血活性的银环蛇毒的致死抑制作用不明显。该抗出血因子不仅在体外实验表现出强的中和出血毒素的活性,而且在体内实验中亦表现出对中毒小鼠良好的治疗作用,因而可能成为新的抗蛇毒药物的有前途的原料。乌梢蛇血清对血循毒的中和能力的获得,可能归因于尖吻蝮与乌梢蛇之间捕食与被捕食相互作用的关系。     

Identification and evolution of venom phospholipase A2 inhibitors from Protobothrops elegans serum

The cDNAs encoding venom phospholipase A(2) (PLA(2)) inhibitors (PLIs), named Protobothrops elegans (Pe)γPLI-A, PeγPLI-B, PeαPLI-A, and PeαPLI-B, were cloned from the P. elegans liver cDNA library. They were further divided into several constituents due to nucleotide substitutions in their open reading frames. For PeαPLI-A, two constituents, PeαPLI-A(a) and PeαPLI-A(b), were identified due to three nonsynonymous substitutions in exon 3. Far-western blot and mass-spectrometry analysis of the P. elegans serum proteins showed the presence of γPLIs, and αPLIs, which can bind venom PLA(2)s. In αPLIs from Protobothrops sera, A or B subtype-specific amino acid substitutions are concentrated only in exon 3. A comparison of γPLIs showed that γPLI-As are conserved and γPLI-Bs diversified. Mathematical analysis of the nucleotide sequences of Protobothrops γPLI-B cDNAs revealed that the particular loops in the three-finger motifs diversified by accelerated evolution. Such evolutionary features should have made serum PLIs acquire their respective inhibitory activities to adapt to venom PLA(2) isozymes.     

Intraspecific variation in the venoms of the South American rattlesnake (Crotalus durissus terrificus)

The venom of eight individual Crotalus durissus terrificus snakes from the State of Minas Gerais, Brazil, in addition to pooled venom from Butantan Institute, were compared. Snakes were captured in distinct locations, some of them 600 km apart: Conselheiro Lafaiete, Entre Rios de Minas, Itauna, Itapecerica, Lavras, Patos de Minas, Paracatu, and Santo Antonio do Amparo. The crude venoms were tested for proteolytic, phospholipase A2, platelet aggregating, and hemagglutinating activities. The venoms were also analyzed by polyacrylamide gel electrophoresis (PAGE) and isoelectric focusing (IEF). Chromatographic patterns of venom proteins on both gel-filtration and anion-exchange chromatographies were also performed. All venoms presented high phospholipase A2 and platelet-aggregating activities, but only minimal hemagglutinating or proteolytic activities were found. Gel-filtration chromatography showed a characteristic profile for most venoms where four main peaks were separated, including the typical ones where convulxin and crotoxin were identified; however, peaks with high amounts of lower molecular weight proteins were found in the venoms from the Santo Antonio do Amparo location and Butantan Institute, characterizing these venoms as crotamine positive. Anion-exchange chromatographies presented a similar protein distribution pattern, although the number of peaks (up to ten) distinguished some venom samples. Consistent with these results, polyacrylamide gels that were silver stained after venom separation by PAGE or IEF presented a similar qualitative band distribution, although a quantitative heterogeneity was detected among venoms. Our results suggest that the variability found in venom components of C. d. terrificus venoms captured in Minas Gerais State may be genetically inherited and/or environmentally induced.     

Comparative analysis of the venom proteomes of Vipera ammodytes ammodytes and Vipera ammodytes meridionalis

The venom proteomics of Vipera ammodytes ammodytes and Vipera ammodytes meridionalis, snakes of public health significance and the most poisonous reptiles in Europe, were analyzed by FPLC, 2-D electrophoresis, sequence analysis, and MS/MS. FPLC analysis showed the presence of l-amino acid oxidase, monomeric and heterodimeric phospholipases A2, C-type lectin protein, and proteinases in the venom of V. a. ammodytes. Representatives of the same protein families were found in the venom of the other subspecies, V. a. meridionalis. N-terminally identical PLA2 neurotoxins were identified in both venoms. Difference in the PLA2 compositions of the venoms was also observed: a monomeric protein with phospholipase A2 activity, identical in the first 20 amino acid residues to the catalitically inactive acidic component of the heterodimeric PLA2 present in both venoms, was found only in that of V. a. meridionalis. Probably, this protein represents an intermediate form of the two components of the heterodimer. 2-D electrophoresis and MS/MS analysis showed that the two venoms shared a number of protein families: monomeric and heterodimeric Group II PLA2s, serine proteinases, Group I, II, and III metalloproteinases, l-amino acid oxidases (LAAOs), cysteine-rich secretory proteins, disintegrins, and growth factors. Totally, 38 venom components of the V. a. ammodytes, belonging to 9 protein families, and 67 components of the V. a. meridionalis venom belonging to 8 protein families were identified. The venom proteome of V. a. ammodytes shows larger diversity of proteins (139) in comparison to that of V. a. meridionalis (104 proteins). Most of the proteins are homologues of known representatives of the respective protein families. The protein compositions explain clinical effects of the V. ammodytes snakebites, such as difficulties in the breathing, paralysis, apoptosis, cloting disorders, hemorrhage, and tissue necrosis. The lists of secreted proteins by the two vipers can be used for further study of structure-function relationships in the toxins and for prediction and treatment of snakebite consequences.     

Snake venomics and antivenomics of the arboreal neotropical pitvipers Bothriechis lateralis and Bothriechis schlegelii

We report the comparative proteomic characterization of the venoms of two related neotropical arboreal pitvipers from Costa Rica of the genus Bothriechis, B. lateralis (side-striped palm pit viper) and B. schlegelii (eyelash pit viper). The crude venoms were fractionated by reverse-phase HPLC, followed by analysis of each chromatographic fraction by SDS-PAGE, N-terminal sequencing, MALDI-TOF mass fingerprinting, and collision-induced dissociation tandem mass spectrometry of tryptic peptides. The venom proteomes of B. lateralis and B. schlegelii comprise similar number of distinct proteins belonging, respectively, to 8 and 7 protein families. The two Bothriechis venoms contain bradykinin-potentiating peptides (BPPs), and proteins from the phospholipase A 2 (PLA 2), serine proteinase, l-amino acid oxidase (LAO), cysteine-rich secretory protein (CRISP), and Zn (2+)-dependent metalloproteinase (SVMP) families, albeit each species exhibit different relative abundances. Each venom also contains unique components, for example, snake venom vascular endothelial growth factor (svVEGF) and C-type lectin-like molecules in B. lateralis, and Kazal-type serine proteinase inhibitor-like proteins in B. schlegelii. Using a similarity coefficient, we estimate that the similarity of the venom proteins between the two Bothriechis taxa may be <10%, indicating a high divergence in their venom compositions, in spite of the fact that both species have evolved to adapt to arboreal habits. The major toxin families of B. lateralis and B. schlegelii are SVMP (55% of the total venom proteins) and PLA 2 (44%), respectively. Their different venom toxin compositions provide clues for rationalizing the distinct signs of envenomation caused by B. schlegelii and B. lateralis. An antivenomic study of the immunoreactivity of the Instituto Clodomiro Picado (ICP) polyvalent antivenom toward Bothriechis venoms revealed that l-amino acid oxidase and SVMPs represent the major antigenic protein species in both venoms. Our results provide a ground for rationalizing the reported protection of the ICP polyvalent antivenom against the hemorrhagic, coagulant, defibrinating, caseinolytic and fibrin(ogen)olytic activities of Bothriechis ( schlegelii, lateralis) venoms. However, these analyses also evidenced the limited recognition capability of the polyvalent antivenom toward a number of Bothriechis venom components, predominantly BPPs, svVEGF, Kazal-type inhibitors, some PLA 2 proteins, some serine proteinases, and CRISP molecules.     

Pseudechis australis venomics: adaptation for a defense against microbial pathogens and recruitment of body transferrin

The venom composition of Pseudechis australis, a widely distributed in Australia reptile, was analyzed by 2-DE and mass spectrometric analysis. In total, 102 protein spots were identified as venom toxins. The gel is dominated by horizontal trains of spots with identical or very similar molecular masses but differing in the pI values. This suggests possible post-translational modifications of toxins, changing their electrostatic charge. The results demonstrate a highly specialized biosynthesis of toxins destroying the hemostasis (P-III metalloproteases, SVMPs), antimicrobial proteins (L-amino acid oxidases, LAAOs, and transferrin-like proteins, TFLPs), and myotoxins (phospholipase A(2)s, PLA(2)s). The three transferrin isoforms of the Australian P. australis (Elapidae snake) venom are highly homologous to the body transferrin of the African Lamprophis fuliginosus (Colubridae), an indication for the recruitment of body transferrin. The venomic composition suggests an adaptation for a defense against microbial pathogens from the prey. Transferrins have not previously been reported as components of elapid or other snake venoms. Ecto-5'-nucleotidases (5'-NTDs), nerve growth factors (VNGFs), and a serine proteinase inhibitor (SPI) were also identified. The venom composition and enzymatic activities explain the clinical manifestation of the king brown snakebite. The results can be used for medical, scientific, and biotechnological purposes.     

A multifaceted analysis of viperid snake venoms by two-dimensional gel electrophoresis: an approach to understanding venom proteomics

The complexity of Viperid venoms has long been appreciated by investigators in the fields of toxinology and medicine. However, it is only recently that the depth of that complexity has become somewhat quantitatively and qualitatively appreciated. With the resurgence of two-dimensional gel electrophoresis (2-DE) and the advances in mass spectrometry virtually all venom components can be visualized and identified given sufficient effort and resources. Here we present the use of 2-DE for examining venom complexity as well as demonstrating interesting approaches to selectively delineate subpopulations of venom proteins based on particular characteristics of the proteins such as antibody cross-reactivity or enzymatic activities. 2-DE comparisons between venoms from different species of the same genus (Bothrops) of snake clearly demonstrated both the similarity as well as the apparent diversity among these venoms. Using liquid chromatography/tandem mass spectrometry we were able to identify regions of the two-dimensional gels from each venom in which certain classes of proteins were found. 2-DE was also used to compare venoms from Crotalus atrox and Bothrops jararaca. For these venoms a variety of staining/detection protocols was utilized to compare and contrast the venoms. Specifically, we used various stains to visualize subpopulations of the venom proteomes of these snakes, including Coomassie, Silver, Sypro Ruby and Pro-Q-Emerald. Using specific antibodies in Western blot analyses of 2-DE of the venoms we have examined subpopulations of proteins in these venoms including the serine proteinase proteome, the metalloproteinase proteome, and the phospholipases A2 proteome. A functional assessment of the gelatinolytic activity of these venoms was also performed by zymography. These approaches have given rise to a more thorough understanding of venom complexity and the toxins comprising these venoms and provide insights to investigators who wish to focus on these venom subpopulations of proteins in future studies.