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Background & objectives: The major limiting factor in the prevention of suicide is the limited knowledge on molecular insights in individuals at risk. Identification of peripheral protein markers which can classify individuals at high-risk of suicide might aid in early diagnosis and effective medical intervention. The aim of the present study was, therefore, to analyze the differential regulation of plasma proteins in individuals with deliberate self-harm compared to controls. Methods: Using two-dimensional gel electrophoresis coupled with matrix-assisted laser desorption-ionization mass spectrometry, differentially expressed plasma proteins were identified in study participants with deliberate self-harm compared to age- and gender-matched controls. The finding was validated using mass spectrometry-based isotope-labelled relative quantification and Western blot analysis in a new set of individuals with deliberate self-harm and controls. Results: The plasma proteomic analysis showed that apolipoprotein A-IV (Apo A-IV ) was downregulated by 2.63-fold (confidence interval: 1.52-4.54) in individuals with deliberate self-harm (n=10) compared to matched controls, which was consistent in mass spectrometry-based relative quantification and Western blot analysis performed in an independent set of individuals with deliberate self-harm (n=18). In addition, plasma levels of total cholesterol, esterified cholesterol and high-density lipoprotein (HDL) were observed to be significantly lower individuals with deliberate self-harm compared to controls. Interpretation & conclusions: Apo A-IV, which plays a crucial role in the esterification of free cholesterol, was found to be downregulated with concomitantly decreased levels of HDL, esterified cholesterol and total cholesterol in individuals with deliberate self-harm compared to matched controls. The present findings might provide a link between the differential regulation of plasma proteins and the previously reported results on altered cholesterol levels in individuals with deliberate self-harm.
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Brucella abortus is a bacterium that causes brucellosis and is the causative agent of worldwide zoonoses. Pathogenesis of the B. abortus infection is complicated, and several researchers have attempted to elucidate the infection mechanism of B. abortus. While several proteins have been revealed as pathogenic factors by previous researchers, the underlying mechanism of B. abortus infection is unresolved. In this study, we identified proteins showing different expression levels in B. abortus mutants with different biological characteristics that were generated by random insertion of a transposon. Five mutants were selected based on biological characteristics, in particular, their growth features. Total proteins of mutant and wild-type B. abortus were purified and subjected to two-dimensional gel electrophoresis. Thirty protein spots of each mutant with expression increases or decreases were selected; those with a change of more than 2-fold were compared with the wild-type. Selected spots underwent liquid chromatography tandem mass spectrometry for peptide analysis. DnaK and ClpB, involved in protein aggregation, increased. SecA and GAPDH, associated with energy metabolism, decreased in some mutants with a growth rate slower than that of the wild-type. Mutants with slower growth showed a decrease in energy metabolism-related proteins, while mutants with faster growth showed an increase in pathogenicity-related proteins.
Subject(s)
Brucella abortus , Brucella , Brucellosis , Chromatography, Liquid , Electrophoresis, Gel, Two-Dimensional , Energy Metabolism , Population Characteristics , Sequence Analysis, Protein , Tandem Mass Spectrometry , ZoonosesABSTRACT
Objective:To study the differentially expressed proteins in saliva of health people and the patients with oral squamous cell carcinoma(OSCC).Methods:Saliva of 17 cases with OSCC and paired health subjects was collected,the proteins in the saliva were examined by two-dimensional gel electrophoresis (2-DE) separation,the proteins were examined by 2-DE separation,the saliva proteome dimensional electrophoresis profiles were obtained by MALDI-TOF/MS mass spectrometric identification,the information of the differentially expressed protein in OSCC group was studied by NCBI database bioinformatics analysis.Results:10 proteins differentially expressed between the 2 groups were observed by mass spectrometry.Bioinformatics analysis showed that S100A8,S100A8/S100A9 and Epidermal cytokeratin 2(EK2) were highly expressed in the saliva of OSCC cases.Conclusion:S100A8,S100A8/S100A9 and EK2 may be related to the development of OSCC.
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La abeja africanizada es la más común en la apicultura colombiana y a su veneno (apitoxina) se le han atribuido propiedades terapéuticas para diferentes enfermedades, sin mayor soporte científico. Al revisar en la literatura los reportes publicados sobre el análisis proteómico de la apitoxina, se encontraron cuatro métodos distintos para la extracción de proteínas de la apitoxina. El primer método consiste en resuspender la apitoxina en Urea 7 M, precipitar con acetona y finalmente resuspender en Urea 7 M y CHAPS 4 %. Para el segundo método se resuspende la apitoxina en buffer de lisis, se precipita con ácido tricloroacético, y luego se resuspende en Urea 7 M y CHAPS 4 %. El tercer método es igual al anterior, excepto que la precipitación se realiza con acetona en vez de ácido tricloroacético. Finalmente, el cuarto método consiste en resuspender la apitoxina en agua destilada, precipitar con acetona y resuspender en Urea 7 M y CHAPS 4 %. Este trabajo se enfocó en comparar el desempeño de estos cuatro métodos de extracción y determinar el método con el mejor resultado en cuanto a la concentración e integridad obtenida de las proteínas. De los distintos métodos evaluados, se encontró que los mejores resultados en cuanto a concentración de proteínas se obtuvieron con la resuspensión de apitoxina en buffer de lisis y precipitación con acetona (método 3) y con el método de resuspensión de apitoxina en agua destilada y precipitación con acetona (método 4). De estos, el mejor método de extracción en cuanto a integridad de las proteínas y perfil proteómico fue el de resuspensión de apitoxina en buffer de lisis seguido de precipitación con acetona (método 3).
The Africanised bee is the most common type of bee in Colombia, and therapeutic properties for different diseases have been attributed to its venom, without much scientific support. A literature search of reports on the proteomic analysis of honeybee venom yielded four different methods for extracting proteins from bee venom. The first method consists in resuspending the venom in 7 M Urea, followed by precipitation with acetone and finally resuspending the pellet in 7 M Urea and 4 % CHAPS. For the second method, the venom is resuspended in lysis buffer, precipitated with trichloroacetic acid, and then resuspended in 7 M Urea and 4 % CHAPS. The third method is similar to the previous one, except that the precipitation step is performed with acetone instead of trichloroacetic acid. Finally, the fourth method is to resuspend the venom in distilled water, precipitate with acetone and resuspend in 7 M Urea and 4 % CHAPS. This work focused on comparing the performance of these four extraction methods, in order to determine the method with the best results in terms of concentration and integrity of the proteins obtained. Of the four methods evaluated, the best results in terms of protein concentration and yield were obtained by resuspending the bee venom in lysis buffer followed by precipitation with acetone (method 3), and by resuspending in distilled water followed by precipitation with acetone (method 4). Of these, the method that maintained protein integrity and yielded the best proteomic profile was that in which the bee venom was resuspended in lysis buffer followed by precipitation with acetone (method 3).
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Abstract Schistosomiasis, a chronic disease that affects million people worldwide, is caused by trematode flukes of the genus Schistosoma. The lack of an anti-schistosomiasis vaccine and massive monotherapy with praziquantel reinforces the need for search and development of new therapeutic drugs. Recently, we demonstrated that the essential oil of Piper cubeba L., Piperaceae, and their derivative dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin, presents in vitro and in vivo activities against Schistosoma mansoni. Here, we identified changes in the protein expression after exposure to dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin. We applied two-dimensional gel electrophoresis (2-DE) to S. mansoni soluble protein extracts and observed at least 38 spots to be affected by dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin. We further identified 25 differentially expressed proteins by mass spectrometry. Enrichment for biological processes and predictive analyses of protein-protein interactions suggest that dibenzylbutyrolactolic (-)-6,6'-dinitrohinokinin targets proteins involved mainly in metabolic processes, especially carbohydrate metabolism. In summary, this study provides an interesting approach to understand the anti-parasitic activity of semi-synthetic (-)-6,6'-dinitrohinokinin a derivative compound from lignan and for the development of new therapy strategies.
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Naoxintong capsule has beneficial effects for activating blood circulation, dispersing blood stasis and dredging collateral. It is widely used in the treatment of coronary heart disease, angina pectoris, stroke and cardiovascular disease. However, the pharmacodynamic basis and possible mechanism of its preventive effects are not clear. In this study, 10 male and 10 female C57BL/6 mice were used, and were randomly divided into the control group (saline) and Naoxintong group. Adaptively fed for 7 days in common conditions, mice were given Naoxintong capsule or saline for 3 days via intragastric administration. Serum was collected from 6 mice in each group 1 h after the last administration. Serum proteins were prepared to do two-dimensional gel electrophoresis. Then image analysis and mass spectrometry detection were carried out to screen and identify the differentially expressed proteins and make bioinformatics analysis. It was found that 24 differentially expressed proteins between Naoxintong group and control group. Compared with the control group, 12 proteins were increased, and 12 were decreased. The proteins were involved in apoptosis signal pathway and vascular endothelial growth factor signal transduction pathway, in which vasohibin-1 is a negative feedback regulation factor in angiogenesis. Western blot showed that the expression of vasohibin-1 in Naoxintong group was reduced, which is consistent with the result in two-dimensional electrophoresis. Serum proteins expression is different between Naoxintong and control groups. The targets of these differentially expressed proteins include endothelial cells, inflammatory cells and platelets. The changes on proteins showed that Naoxintong capsule may ameliorate coronary heart disease and ischemic cerebrovascular disease, and provide potential biological markers to prevent ischemic disease.
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Many studies of protein expression after traumatic brain injury (TBI) have identified biomarkers for diagnosing or determining the prognosis of TBI. In this study, we searched for additional protein markers of TBI using a fluid perfusion impact device to model TBI in S-D rats. Two-dimensional gel electrophoresis and mass spectrometry were used to identify differentially expressed proteins. After proteomic analysis, we detected 405 and 371 protein spots within a pH range of 3-10 from sham-treated and contused brain cortex, respectively. Eighty protein spots were differentially expressed in the two groups and 20 of these proteins were identified. This study validated the established biomarkers of TBI and identified potential biomarkers that could be examined in future work.
Muitos estudos de expressão proteica após lesão cerebral traumática (LCT) identificam biomarcadores para determinação diagnóstica ou prognóstica do LCT. No presente estudo, foram investigados marcadores proteicos adicionais de LCT, através de um aparelho de impacto no fluxo e perfusão em ratos S-D. Eletroforese bidimensional em gel e espectrometria de massa foram utilizadas para identificar diferentes proteínas expressas. Após a análise proteômica, detectamos marcas de proteínas 405 e 371, com pH variando entre 3-10 no córtex de ratos sham e naqueles com contusão cerebral, respectivamente. Oitenta marcas proteicas foram expressas nos dois grupos e 20 destas proteínas foram identificadas. Este estudo validou o estabelecimento de biomarcadores de LCT e identificou potencial biomarcadores que poderão ser estudados em estudos futuros.
Subject(s)
Animals , Male , Biomarkers/analysis , Brain Injuries/diagnosis , Cerebral Cortex/chemistry , Proteomics , Brain Chemistry , Brain Injuries/metabolism , Disease Models, Animal , Electrophoresis, Gel, Two-Dimensional , Mass Spectrometry , Prognosis , Random Allocation , Rats, Sprague-Dawley , Reference Values , Time FactorsABSTRACT
This article was aimed to study the proteomic spectra expression of traditional Chinese medicine (TCM) cold and heat constitution rats with two-dimensional gel electrophoresis (2-DE), in order to search for the cold and heat-associated proteins for the investigation of the biological basis of TCM cold and heat body constitution formation. The total protein in rat’s liver cell was extracted. The 2-DE and MALDI-TOF/TOF mass spectrometry (MS) were used in the screening and identification of differentially expressed proteins of cold and heat constitution rats. The results showed that a total of 10 different points in the protein expression were obtained with statistical significance after screening and MS, which were carbamoyl-phosphate synthase, protein disulfide isomerase associated 3, catalase, hydroperoxide isomerase, cytosol aminopeptidase, glutamate dehydrogenase 1, 3-hydroxy-3-methylglutaryl-coenzyme A synthase 2, heat shock protein 60 (Hsp60) precursor, homocysteine, 78 kDa glucose-regulated protein precursor. It was concluded that some differences were existed in the proteomic spectra expression of TCM cold and heat constitution rats. The abnormality of enzyme protein metabolism may be one of the material bases for the formation of cold and heat constitution.
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Objective To identify energy metabolism-proteins of mice midbrain by using the proteomic technique,and to investi-gate the relationship between these proteins and neural diseases.Methods Two-dimensional gel electrophoresis was used to sepa-rate totally soluble proteins extracted from mice midbrain.Some protein spots on two-dimensional gel electrophoresis gels were ana-lyzed by using matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).Results 24 protein spots related with energy metabolism were separated by two-dimensional gel electrophoresis and identified by using MALDI-TOF MS successfully.Conclusion The establishment of energy metabolism-related proteins map of mice midbrain lays a foundation for the research on the involvement of these proteins in neural disease pathogenesis.
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Naja kaouthia, Ophiophagus hannah, Bungarus fasciatus and Calloselasma rhodostoma are four venomous snakes indigenous to Malaysia. In the present study, their proteomic profile by two-dimensional gel electrophoresis (2-DE) have been separated and compared.
Subject(s)
Animals , Alismatales/classification , Spectrum Analysis/methods , Snake Bites , Cobra Neurotoxin Proteins/analysis , Poisons/analysisABSTRACT
Naja kaouthia, Ophiophagus hannah, Bungarus fasciatus and Calloselasma rhodostoma are four venomous snakes indigenous to Malaysia. In the present study, their proteomic profile by two-dimensional gel electrophoresis (2-DE) have been separated and compared.
Subject(s)
Animals , Alismatales/classification , Spectrum Analysis/methods , Cobra Neurotoxin Proteins/analysis , Snake Bites , Poisons/analysisABSTRACT
Introduction The aim of this study was to explore the environment of Echinococcus granulosus (E. granulosus) protoscolices and their relationship with their host. Methods Proteins from the hydatid-cyst fluid (HCF) from E. granulosus were identified by proteomics. An inductively coupled plasma atomic emission spectrometer (ICP-AES) was used to determine the elements, an automatic biochemical analyzer was used to detect the types and levels of biochemical indices, and an automatic amino acid analyzer was used to detect the types and levels of amino acids in the E. granulosus HCF. Results I) Approximately 30 protein spots and 21 peptide mass fingerprints (PMF) were acquired in the two-dimensional gel electrophoresis (2-DE) pattern of hydatid fluid; II) We detected 10 chemical elements in the cyst fluid, including sodium, potassium, calcium, magnesium, copper, and zinc; III) We measured 19 biochemical metabolites in the cyst fluid, and the amount of most of these metabolites was lower than that in normal human serum; IV) We detected 17 free amino acids and measured some of these, including alanine, glycine, and valine. Conclusions We identified and measured many chemical components of the cyst fluid, providing a theoretical basis for developing new drugs to prevent and treat hydatid disease by inhibiting or blocking nutrition, metabolism, and other functions of the pathogen. .
Subject(s)
Animals , Humans , Cyst Fluid/chemistry , Echinococcosis , Echinococcus granulosus/chemistry , Electrophoresis, Polyacrylamide Gel , Helminth Proteins/analysisABSTRACT
Aims: Find a suitable method for the protein extraction from flower buds of Solanum lycopersicum. Study Design: Compare some kinds of protein extraction methods and find the best one among them suitable to tomato flower buds. Place and Duration of Study: Biological Science and Technology College, between June 2010 and July 2011. Methodology: The proteins for electrophoresis were extracted using different methods, such as trichloroacetic acid /acetone (TCA/acetone), Sodium dodecyl sulfate (SDS), Trissaturated phenol (Tris-Phen), Phenol/SDS and Direct lysis method. After silver staining, different patterns of protein spots were observed in the gels. Results: Few spots were found by SDS and Phenol/SDS extractions, more spots by immediate dissolution but the most impurities, less protein productivity though more spots by Tris-Phen extractions, and more protein productivity and better apart effect by TCA/acetone. The 2-DE image background was the clear and the protein spots were the most by TCA/acetone method. Conclusion: TCA/acetone method is much more suitable as extraction method for protein two-dimensional electrophoresis of tomato flower buds.
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OBJECTIVE: To observe the changes in protein expression induced by botulinum toxin A (BoNT-A) injection and to characterize the molecular and cellular action of mechanisms of BoNT-A injection on skeletal muscles using proteomic elements as biomarkers. METHODS: BoNT-A was injected into left gastrocnemius muscles of 12 Sprague-Dawley rats (2 months of age) at a dosage of 5 units/kg body weight. For the controls same volume of normal saline was injected to right gastrocnemius muscle of each rat. Muscle samples were obtained at 4 time points (3 rats per time point): 3, 7, 14, and 56 day post-injection. To reveal the alterations in muscle protein, we performed 2-dimensional electrophoresis (2DE) and compared Botox group and normal saline group at each time point. Altered protein spots in 2DE were identified using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometer (MALDI-TOF MS) proteomics analysis. RESULTS: Compared with normal saline group, 46 protein spots showed changed protein expression. Twelve protein spots demonstrated increased volume and 34 protein spots demonstrated decreased volume. Among spots of decreased volume, 17 spots showed statistically significant differences. Thirty-eight identified proteins were associated with alterations in energy metabolism, muscle contractile function, transcription, translation, cell proliferation, and cellular stress response. CONCLUSION: BoNT-A gives influences on muscle contractile function and energy metabolism directly or indirectly besides neurotoxic effects. Proteomic expression provides better understanding about the effect of BoNT-A on skeletal muscle.
Subject(s)
Animals , Rats , Body Weight , Botulinum Toxins , Botulinum Toxins, Type A , Cell Proliferation , Electrophoresis , Electrophoresis, Gel, Two-Dimensional , Energy Metabolism , Muscle Proteins , Muscle, Skeletal , Muscles , Proteins , Proteomics , Rats, Sprague-DawleyABSTRACT
Objective To screen the differential expression proteins in the children with neuroblastoma (NB) by proteomics tools.Methods Three specimens were collected from the patients diagnosed Ⅳstage NB by biopsy at Department of Pediatric Surgery of Chinese PLA General Hospital in Beijing from July to December,2011.Another three specimens were acquired from the same patients underwent tumor excision.Average age was 3.17 years.Proteins in neuroblastoma before and after chemotherapy were separated by two dimensional gel electrophoresis,analyzed by high performance liquid chromatography-eleetrospray tandem MS (Nano-UPLC-ESIMS/MS).Results After two dimensional gel electrophoresis,we obtained the maps about tissues before and after chemotherapy.There were 7 differential protein spots identified by using the Image Master two dimensional gel electrophoresis software,in which 2 were up-regulated,including Nm23 protein and neuropolypeptide h3,5were down-regulated after chemotherapy,including stathminl,heat shock protein 27,mitochondrial short-chain enoyl-coenzyme A,peroxiredoxin 1 and peroxiredoxin 3.Conclusion The differential expression proteins of children neuroblastoma before and after chemotherapy were successfully identified by two dimensional gel electrophoresis and Nano-UPLC-ESI-MS/MS.
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Objective To obtain two-dimensional gel electrophoresis maps of the renal tissue proteins of normal and chronic intermittent hypoxia(CIH) rats for identifying the diferentially expressed proteins in the CIH rats.MethodsCIH rat models were established, and the proteins in the renal tissue underwent two-dimensional gel electrophoresis with immobiline pH gradientisoeleclricfocusingasthefirstdimensionandverticalSDS-PAGEasthesecond dimension.Analysis of 2-DE maps was used to determine differential expression of proteins between the two groups by ImageMaster 2D Platinum 5.0, and four protein spots expressed differently were picked up for further identification by MALDI-TOF-MS.Results Matched and compared with those of control group, 112 protein spots were determined with differently expressive levels in CIH group.By MALDI-TOF-MS, three protein spots of them were identified as ATP synthase delta subunit of mitochondrial precursor, catechol O-methyltransferase, apurinic/apyrimidinic endonudease.Conclusions There is obvious difference in expressive proteomes in renal tissue between normal and chronic intermittent hypoxia rats.The functions of those identified proteins are involved in cellular energy metabolism, apoptosis, signal transduction, anti-cell injury and hormone metabolism,so that proteomics can serve as a new approach in the study of obstructive sleep apnea-hypopnea syndrome to discover new therapeutic targets.
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Diagnostic biomarkers for early detection of renal cell carcinoma (RCC) are in great need. In the present study, we compared the serum protein profiles of patients with small RCC to those of healthy individuals to identify the differentially expressed proteins with potential to serve as biomarkers. Serum samples were collected from 10 patients with small RCC and 10 healthy individuals. The serum protein expression profiles were analyzed by two-dimensional (2-D) gel electrophoresis. Twenty-seven proteins with differences in expression levels between RCC patients and healthy volunteers were identified. Of these, 19 were expressed at different levels and eight were expressed in serum from the RCC group, but not from the control group. Six differentially expressed proteins identified by using mass spectrometry included coagulation factor XIII B, complement C3 and its precursor, misato homolog 1 (isoform CRA_b), hemopexin, and alpha-1-B-glycoprotein. Some of these serum proteins are known regulators of tumor progression in human malignancies. In conclusion, we successfully applied 2-D gel electrophoresis and identified six serum proteins differentially expressed between patients with small RCC and healthy volunteers. These proteins may provide novel biomarkers for early detection and diagnosis of human RCC.
Subject(s)
Aged , Blood Proteins/chemistry , Carcinoma, Renal Cell/blood , Carcinoma, Renal Cell/metabolism , Case-Control Studies , Electrophoresis, Gel, Two-Dimensional , Female , Gene Expression Regulation, Neoplastic , Humans , Kidney Neoplasms/blood , Kidney Neoplasms/metabolism , Male , Mass Spectrometry/methods , Middle Aged , Protein Isoforms , Trypsin/chemistry , Biomarkers, Tumor/metabolismABSTRACT
Sample preparation for Two-dimensional gel electrophoresis (2DE) is tedious and not sufficient to provide a comparative profile of secreted proteins for various strains of M. tuberculosis. High lipid content in mycobacteria limits the use of common methods as it can hinder the 2DE run. This study highlights the significance of SDS-TCA procedure over common used methods for the preparation of sample from culture filtrate as well as other proteinaceous fluids.
Subject(s)
Humans , Chromatography, Gel , Culture Media , Lipids , Mycobacterium tuberculosis/metabolism , Diagnostic Techniques and Procedures , Electrophoresis, Gel, Two-Dimensional , MethodsABSTRACT
Snake venoms comprise a highly complex mixture of proteins, which requires for their characterization the use of versatile two-dimensional electrophoresis techniques. In the present study, venoms obtained from eight snakes (Ophiophagus hannah, Naja kaouthia, Naja sumatrana, Bungarus fasciatus, Trimeresurus sumatranus, Tropidolaemus wagleri, Enhydrina schistosa and Calloselasma rhodostoma) commonly found in Malaysia were separated based on two independent properties, isoelectric point (pI) and molecular weight (MW). Many differences in snake venoms at the inter-family, inter-subfamily, inter-genus and inter-species levels were revealed. Notably, proteins from individuals of the Viperidae family - Trimeresurus sumatranus, Tropidolaemus wagleri and Calloselasma rhodostoma - were found to be numerous and scattered by the two-dimensional gel electrophoresis (2DE) specifically in regions between 37 and 100 kDa compared to the Elapidae venom proteins. The latter were clustered at the basic and lower molecular mass region (less than 20 kDa). Trains of spots were commonly observed, indicating that these proteins may be derived from post-translational modifications. Ophiophagus hannah (Elapidae) revealed a great amount of protein spots in the higher molecular mass range when compared to Enhydrina schistosa, Naja kaouthia, Naja sumatrana and Bungarus fasciatus. Overall 2DE showed large differences in the venom profile of each species, which might be employed as an ancillary tool to the identification of venomous snake species.(AU)
Subject(s)
Animals , Snake Venoms , Electrophoresis, Gel, Two-Dimensional , ProteinsABSTRACT
Snake venoms comprise a highly complex mixture of proteins, which requires for their characterization the use of versatile two-dimensional electrophoresis techniques. In the present study, venoms obtained from eight snakes (Ophiophagus hannah, Naja kaouthia, Naja sumatrana, Bungarus fasciatus, Trimeresurus sumatranus, Tropidolaemus wagleri, Enhydrina schistosa and Calloselasma rhodostoma) commonly found in Malaysia were separated based on two independent properties, isoelectric point (pI) and molecular weight (MW). Many differences in snake venoms at the inter-family, inter-subfamily, inter-genus and inter-species levels were revealed. Notably, proteins from individuals of the Viperidae family Trimeresurus sumatranus, Tropidolaemus wagleri and Calloselasma rhodostoma were found to be numerous and scattered by the two-dimensional gel electrophoresis (2DE) specifically in regions between 37 and 100 kDa compared to the Elapidae venom proteins. The latter were clustered at the basic and lower molecular mass region (less than 20 kDa). Trains of spots were commonly observed, indicating that these proteins may be derived from post-translational modifications. Ophiophagus hannah (Elapidae) revealed a great amount of protein spots in the higher molecular mass range when compared to Enhydrina schistosa, Naja kaouthia, Naja sumatrana and Bungarus fasciatus. Overall 2DE showed large differences in the venom profile of each species, which might be employed as an ancillary tool to the identification of venomous snake species.