- Dr. Susanta Pahari is a Professor in The Department of Biochemistry, Skyline University, Nigeria.He has a PhD in Bioc... moreDr. Susanta Pahari is a Professor in The Department of Biochemistry, Skyline University, Nigeria.He has a PhD in Biochemistry, MSc in Biochemistry from University of Calcutta, India. In addition, he also has BSc in Chemistry from the University of Calcutta, India.ExperienceHe has over 20 years’ of experience in teaching, training, research and administration in India as well as in abroad. He has done his research work in Indian premier institutes as well as in Singapore, Sweden (Stockholm) and Taipei. He has taught in Jain University, CMR University and leading colleges under Bangalore University, India. He has also worked as Director of Redit
ABSTRACT
Many snake venoms contain toxins which produce profound cardiovascular effects. The site of action of these toxins includes cardiac muscle, vascular smooth muscle and the capillary vascular bed. Some snake venoms, for example, contain... more
Many snake venoms contain toxins which produce profound cardiovascular effects. The site of action of these toxins includes cardiac muscle, vascular smooth muscle and the capillary vascular bed. Some snake venoms, for example, contain peptides that inhibit angiotensin converting enzyme and potentiate the biological actions of bradykinin. Other snake venoms contain structural and functional equivalents of mammalian natriuretic peptides. Sarafotoxins are short peptide toxins found in the venoms of snakes from Atractaspis spp. which display potent vasoconstriction properties. These peptides, which share a high degree of sequence identity with endothelins, recognize and bind to endothelin receptors. Snakes have also evolved toxins which block L-type Ca(2+) currents (eg. calciseptine, FS2 toxins, C(10)S(2)C(2) and S(4)C(8)). Snake venom proteins have also been shown to increase vascular permeability. One such protein, increasing capillary permeability protein (ICPP) has recently been isolated from the venom of Vipera lebetina. ICPP is an extremely potent permeability factor with a structure similar to vascular endothelial growth factor (VEGF). Thus there is a vast array of snake toxins with potent cardiovascular activity. Some of these proteins and peptides have proven to be highly selective tools in the study of physiological processes. Others have been used as probes of potential therapeutic targets or as lead compounds in the development of therapeutic agents. Therefore these and other related snake venom proteins hold great promise in the future understanding and treatment of cardiovascular diseases.
Research Interests:
Overexpression of a clone of vesicular stomatitis virus phosphoprotein P (New Jersey serotype) using T7 promoter withphoAleader sequence and a simpler two-step purification procedure of the expressed protein has been developed. The... more
Overexpression of a clone of vesicular stomatitis virus phosphoprotein P (New Jersey serotype) using T7 promoter withphoAleader sequence and a simpler two-step purification procedure of the expressed protein has been developed. The purified protein retains its ability to activate the transcription reaction. Comparative transcriptional assay using the protein P purified from periplasmic space and from cytosol (in the form of
Research Interests: Kinetics, Membrane Proteins, Western blotting, Recombinant DNA Technology, Escherichia coli, and 9 moreVesicular Stomatitis Virus, New Jersey, Plasmids, Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis, Inclusion Bodies, Protein expression and purification, Biological activity, Recombinant Proteins, and Biochemistry and cell biology
Research Interests: Evolutionary Biology, Genetics, Biology, Medicine, Phylogeny, and 15 moreSequence alignment, Animals, Gene Order, Evolutionary History, Gene Duplication, Gene Structure, Introns, Exon Evolution, Biological activity, Amino Acid Sequence, Sistrurus Venom, Rattlesnake Venom, Gene Evolution, Gene Family, and Molecular Sequence Data
Research Interests:
Research Interests: Evolutionary Biology, Snake venoms, Phylogeny, Enzymes, Sequence alignment, and 15 moreAnimals, Peptides, Gene Duplication, ribosomal RNA, Snake Venom, Crotalus, Mechanism of action, Amino Acid Sequence, Base Sequence, cDNA library, Biochemistry and cell biology, Gene Expression Regulation, Gene expression profiling, Molecular Sequence Data, and Medical biochemistry and metabolomics
Research Interests: Evolutionary Biology, Genetics, Molecular Evolution, Ecological Niche Modeling, Gene expression, and 13 moreSnake venoms, Adaptive Radiation, Animals, Enzyme, Snake Venom, Elapidae, Protein isoforms, Species Specificity, Amino Acid Sequence, Base Sequence, Genetic distance, cDNA library, and Molecular Sequence Data
Dendritic cells (DCs) and macrophages (Mφs) are professional antigen-presenting cells (APCs) that can efficiently phagocytose Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis (TB). It is quite interesting to mention... more
Dendritic cells (DCs) and macrophages (Mφs) are professional antigen-presenting cells (APCs) that can efficiently phagocytose Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis (TB). It is quite interesting to mention here that DCs and Mφs use distinct strategies to combat and eliminate Mtb. Similarly, Mtb employs different mechanisms to counteract the action of DCs and Mφs. Mφs are evolved with specialized, innate, defensive machinery to restrict growth of Mtb at the initial phase of infection. However, DCs are more endowed toward initiating adaptive immunity by activating naïve T cells. During encounter with Mtb, DCs and Mφs deliver discrete functions via triggering through different pattern recognition receptors (PRRs) expressed by these APCs. Mtb-infected DCs and Mφs show differential expression of genes encoding cytokines, chemokines, costimulatory molecules, and adhesion molecules. Interestingly, Mtb impairs the immune defensive machinery by exploiting var...
Research Interests:
Many snake venoms contain toxins which produce profound cardiovascular effects. The site of action of these toxins includes cardiac muscle, vascular smooth muscle and the capillary vascular bed. Some snake venoms, for example, contain... more
Many snake venoms contain toxins which produce profound cardiovascular effects. The site of action of these toxins includes cardiac muscle, vascular smooth muscle and the capillary vascular bed. Some snake venoms, for example, contain peptides that inhibit angiotensin converting enzyme and potentiate the biological actions of bradykinin. Other snake venoms contain structural and functional equivalents of mammalian natriuretic peptides. Sarafotoxins are short peptide toxins found in the venoms of snakes from Atractaspis spp. which display potent vasoconstriction properties. These peptides, which share a high degree of sequence identity with endothelins, recognize and bind to endothelin receptors. Snakes have also evolved toxins which block L-type Ca(2+) currents (eg. calciseptine, FS2 toxins, C(10)S(2)C(2) and S(4)C(8)). Snake venom proteins have also been shown to increase vascular permeability. One such protein, increasing capillary permeability protein (ICPP) has recently been isolated from the venom of Vipera lebetina. ICPP is an extremely potent permeability factor with a structure similar to vascular endothelial growth factor (VEGF). Thus there is a vast array of snake toxins with potent cardiovascular activity. Some of these proteins and peptides have proven to be highly selective tools in the study of physiological processes. Others have been used as probes of potential therapeutic targets or as lead compounds in the development of therapeutic agents. Therefore these and other related snake venom proteins hold great promise in the future understanding and treatment of cardiovascular diseases.
Research Interests:
Research Interests: Microbiology, Immunology, Immune response, Medical Microbiology, Molecular Mechanics, and 12 moreSignal Transduction, Humans, Mycobacterium tuberculosis, Code of Conduct, Animals, Antigen Processing, Antigen Presentation, Immune system, Host Pathogen Interaction, Bacterial infections, Host Pathogen Interactions, and Virus diseases
Research Interests: Kinetics, Membrane Proteins, Western blotting, Recombinant DNA Technology, Escherichia coli, and 9 moreVesicular Stomatitis Virus, New Jersey, Plasmids, Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis, Inclusion Bodies, Protein expression and purification, Biological activity, Recombinant Proteins, and Biochemistry and cell biology
Research Interests:
Research Interests:
Research Interests: Evolutionary Biology, Toxinology, Snake venoms, Phylogeny, Enzymes, and 16 moreSequence alignment, Animals, Peptides, Gene Duplication, ribosomal RNA, Snake Venom, Crotalus, Optometry and Ophthalmology, Mechanism of action, Species Specificity, Amino Acid Sequence, Base Sequence, cDNA library, Biochemistry and cell biology, Gene Expression Regulation, and Gene expression profiling
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Background: Snake venoms are complex mixtures of pharmacologically active proteins and peptides which belong to a small number of superfamilies. Global cataloguing of the venom transcriptome facilitates the identification of new families... more
Background: Snake venoms are complex mixtures of pharmacologically active proteins and peptides which belong to a small number of superfamilies. Global cataloguing of the venom
transcriptome facilitates the identification of new families of toxins as well as helps in understanding the evolution of venom proteomes. Results: We have constructed a cDNA library of the venom gland of a threatened rattlesnake (a pitviper), Sistrurus catenatus edwardsii (Desert Massasauga), and sequenced 576 ESTs. Our results demonstrate a high abundance of serine proteinase and metalloproteinase transcripts, indicating
that the disruption of hemostasis is a principle mechanism of action of the venom. In addition to the transcripts encoding common venom proteins, we detected two varieties of low abundance unique transcripts in the library; these encode for three-finger toxins and a novel toxin possibly generated from the fusion of two genes. We also observed polyadenylated ribosomal RNAs in the venom gland library, an interesting preliminary obsevation of this unusual phenomenon in a reptilian
system. Conclusion: The three-finger toxins are characteristic of most elapid venoms but are rare in viperid venoms. We detected several ESTs encoding this group of toxins in this study. We also
observed the presence of a transcript encoding a fused protein of two well-characterized toxins (Kunitz/BPTI and Waprins), and this is the first report of this kind of fusion in a snake toxin
transcriptome. We propose that these new venom proteins may have ancillary functions for envenomation. The presence of a fused toxin indicates that in addition to gene duplication and
accelerated evolution, exon shuffling or transcriptional splicing may also contribute to generating the diversity of toxins and toxin isoforms observed among snake venoms. The detection of low abundance toxins, as observed in this and other studies, indicates a greater compositional similarity of venoms (though potency will differ) among advanced snakes than has been previously recognized.
transcriptome facilitates the identification of new families of toxins as well as helps in understanding the evolution of venom proteomes. Results: We have constructed a cDNA library of the venom gland of a threatened rattlesnake (a pitviper), Sistrurus catenatus edwardsii (Desert Massasauga), and sequenced 576 ESTs. Our results demonstrate a high abundance of serine proteinase and metalloproteinase transcripts, indicating
that the disruption of hemostasis is a principle mechanism of action of the venom. In addition to the transcripts encoding common venom proteins, we detected two varieties of low abundance unique transcripts in the library; these encode for three-finger toxins and a novel toxin possibly generated from the fusion of two genes. We also observed polyadenylated ribosomal RNAs in the venom gland library, an interesting preliminary obsevation of this unusual phenomenon in a reptilian
system. Conclusion: The three-finger toxins are characteristic of most elapid venoms but are rare in viperid venoms. We detected several ESTs encoding this group of toxins in this study. We also
observed the presence of a transcript encoding a fused protein of two well-characterized toxins (Kunitz/BPTI and Waprins), and this is the first report of this kind of fusion in a snake toxin
transcriptome. We propose that these new venom proteins may have ancillary functions for envenomation. The presence of a fused toxin indicates that in addition to gene duplication and
accelerated evolution, exon shuffling or transcriptional splicing may also contribute to generating the diversity of toxins and toxin isoforms observed among snake venoms. The detection of low abundance toxins, as observed in this and other studies, indicates a greater compositional similarity of venoms (though potency will differ) among advanced snakes than has been previously recognized.