Biochemical and biological properties of Trimeresurus jerdonii venom and characterization of a platelet aggregation-inhibiting acidic phospholipase A(2)

Several biochemical and biological activities such as phospholipase A(2), arginine esterase, proteolytic, L-amino acid oxidase, 5'nucleotidase, acetylcholinesterase, thrombin-like, anticoagulant, and hemorrhagic activities were determined for whole desiccated venom of Trimeresurus jerdonii. An acidic phospholipase (named TJ-PLA(2)) was purified by anionic exchange chromatography, gel filtration, and reverse phase HPLC. TJ-PLA(2) had a molecular weight of 16,000 and a pI of 4.8. TJ-PLA(2) was non-lethal to mice up to an i.p. dose of 15 mg/kg body weight and lacked neurotoxicity and myotoxicity. It induced edema in the footpads of mice. The purified enzyme inhibited ADP- and collagen-induced human platelet aggregation in a manner which was both dose- and time-dependent.

Biochemical and ultrastructural changes of the liver and kidney of the phytoplanktivorous silver carp feeding naturally on toxic Microcystis blooms in Taihu Lake, China

Many experimental studies have documented the impact of microcystins (MC) on fish based on either intraperitoneal injection, or oral gavaging via the diet, but few experiments were conducted by MC exposure through natural food uptake in lakes. In this study, the phytoplanktivorous silver carp were stocked in a large pen set in Meiliang Bay of Taihu Lake where toxic Microcystis blooms occurred in the warm seasons. Fish samples were collected monthly and MC concentrations in liver and kidney of the fish were determined by LC-MS. The maximum MC concentrations in liver and kidney were present in July when damages in ultrastructures of the liver and kidney were revealed by electron microscope. In comparison with previous studies on common carp, silver carp showed less damage and presence of lysosome proliferation in liver and kidney. Silver carp might eliminate or lessen cell damage caused by MC through lysosome activation. Recovery in the ultrastructures of liver and kidney after Microcystis blooms was companied with a significant decrease or even disappearance of MC. Catalase and glutathione S-transferase in liver and kidney of silver carp during Microcystis blooms were significantly higher than before and after Microcystis blooms. The high glutathione pool in liver and kidney of silver carp suggests their high resistance to MC exposure. The efficient antioxidant defence may be an important mechanism of phytoplanktivorous fish like silver carp to counteract toxic Microcystis blooms. (C) 2007 Published by Elsevier Ltd.

Influence of selected Indian immunostimulant herbs against white spot syndrome virus (WSSV) infection in black tiger shrimp, Penaeus monodon with reference to haematological, biochemical and immunological changes

Immunostimulants are the substances, which enhance the non-specific defence mechanism and provide resistance against the invading pathogenic micro-organism. In order to increase the immunity of shrimps against the WSSV, the methanolic extracts of five different herbal medicinal plants like Cyanodon dactylon, Aegle marmelos, Tinospora cordifolia, Picrorhiza kurooa and Eclipta alba were selected and mixed thoroughly in equal proportion. The mixed extract was supplemented with various concentrations viz. 100 (A), 200 (B), 400 (C), and 800 (D) mg kg(-1) through artificial diets individually. The prepared diets (A-D) were fed individually to WSSV free healthy shrimp Penaeus monodon with an average weight of 8.0 +/- 0.5 g for 25 days. Control diet (E), devoid of herbal extract was also fed to shrimps simultaneously. After 25 days of feeding experiment, the shrimps were challenged with WSSV, which were isolated and propagated from the infected crustaceans. The shrimps succumbed to death within 7 days when fed on no herbal immunostimulant diet (E). Among the different concentrations of herbal immunostimulant supplemented diets, the shrimps fed on diet D (800 mg kg(-1)) significantly (P < 0.0001) had more survival (74%) and reduction in the viral load. Also the better performance of haematological, biochemical and immunological parameters was found in the immunostimulant incorporated diets fed shrimps. The present work revealed that the application of herbal immunostimulants will be effective against shrimp viral pathogenesis and they can be recommended for shrimp culture. (c) 2006 Published by Elsevier Ltd.

Biochemical and electron microscopic characterization of the F1F0 ATP Synthase from the hyperthermophilic eubacterium Aquifex aeolicus

The F1F0 ATP synthase has been purified from the hyperthermophilic eubacterium Aquifex aeolicus and characterized. Its subunits have been identified by MALDI-mass spectrometry through peptide mass fingerprinting and MS/MS. It contains the canonical subunits alpha, beta, gamma, delta and epsilon of F-1 and subunits a and c of F-0. Two versions of the b subunit were found, which show a low sequence homology to each other. Most likely they form a heterodimer. An electron microscopic single particle analysis revealed clear structural details, including two stalks connecting F-1 and F-0. In several orientations the central stalk appears to be tilted and/or kinked. It is unclear whether there is a direct connection between the peripheral stalk and the 6 subunit. (c) 2006 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Magnetic microsphere and its use in biochemical separation and analysis

Magnetic microsphere comprises a magnetically responsive metal or metal oxide core surrounded by a polymer shell with active groups. Nowadays, methods of directly coating polymer, monomer polymerazation, impregnation, extrusion and biological synthesis are generally used to prepare magnetic particles. This kind of superparamagnetic microspheres can be attached to chemical, biochemical and biological substances by their active groups, then applying a magnetic field to separate from the media. Preparation and utilization of magnetic microspheres in immunoassay, nucleic acid hybrization assay, gene sequencing, cell isolation, enzyme immoblization, receptor isolation and other Gelds are reviewed with 44 references in this paper. Also, the further development is outlooked.

mtDNA mutation C1494T, haplogroup A, and hearing loss in Chinese

Mutation C1494T in mitochondrial 12S rRNA gene was recently reported in two large Chinese families with aminoglycoside-induced and nonsyndromic hearing loss (AINHL) and was claimed to be pathogenic. This mutation, however, was first reported in a sample f

Expression of VEGFR-2 on HaCaT cells is regulated by VEGF and plays an active role in mediating VEGF induced effects

Vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 play important roles in mitogenesis and chemotaxis of endothelial cells. In normal human skin, VEGF is expressed and secreted by epidermal keratinocytes. Emerging data suggest that keratin

mtDNA haplogroup distribution in Chinese patients with Leber's hereditary optic neuropathy and G11778A mutation

Mitochondrial DNA background has been shown to be involved in the penetrance of Leber's hereditary optic neuropathy (LHON) in western Eurasian populations. To analyze mtDNA haplogroup distribution pattern in Han Chinese patients with LHON and G11778A muta

High penetrance of sequencing errors and interpretative shortcomings in mtDNA sequence analysis of LHON patients

For identifying mutation(s) that are potentially pathogenic it is essential to determine the entire mitochondrial DNA (mtDNA) sequences from patients suffering from a particular mitochondrial disease, such as Leber hereditary optic neuropathy (LHON). Howe

Co-occurrence of A1555G and G11778A in a Chinese family with high penetrance of Leber's hereditary optic neuropathy

Co-occurrence of double pathogenic mtDNA mutations with different claimed pathological roles in one mtDNA is infrequent. It is tentative to believe that each of these pathogenic mutations would have its own deleterious effect. Here we reported one three-g

Identification and characterization of hypoxia-induced genes in Carassius auratus blastulae embryonic cells using suppression subtractive hybridization

Organisms living in water are inevitably exposed to periods of hypoxia. Environmental hypoxia has been an important stressor having manifold effects on aquatic life. Many fish species have evolved behavioral, physiological, biochemical and molecular adaptations that enable them to cope with hypoxia. However, the molecular mechanisms of hypoxia tolerance in fish, remain unknown. in this study, we used suppression subtractive hybridization to examine the differential gene expression in CAB cells (Carassius auratus blastulae embryonic cells) exposed to hypoxia for 24 h. We isolated 2100 clones and identified 211 differentially expressed genes (e-value <= 5e-3; Identity > 45%). Among the genes whose expression is modified in cells, a vast majority involved in metabolism, signal transduction, cell defense, angiogenesis, cell growth and proliferation. Twelve genes encoding for ERO1-L, p53, CPO, HO-1, MKP2, PFK-2, cystatin B, GLUT1, BTG1, TGF beta 1, PGAM1, hypothetical protein F1508, were selected and identified to be hypoxia-induced using semi-quantitive RT-PCR and real-time PCR. Among the identified genes, two open reading frames (ORFs) encoding for CaBTG1 and Cacystatin B were obtained. The deduced amino acid sequence of CaBTG1 had 94.1%, 72.8%, 72.8%, 72.8%, 68.6% identity with that of DrBTG1, HsBTG1, BtBTG1, MmBTG1 and XIBTG1. Comparison of Cacystatin B with known cystatin B, the molecules exhibited 49.5 to 76.0% identity overall. These results may provide significant information for further understanding of the adaptive mechanism by which C. auratus responds to hypoxia. (c) 2008 Elsevier Inc. All rights reserved.

Isolation and characterization of a rhabdovirus from co-infection of two viruses in mandarin fish

Co-infection of two viruses has been observed in mandarin fish (Siniperca chuatsi), but the two viruses have not been characterized. In this study, a rhabdovirus has been isolated from the co-infected two viruses extracted from the diseased mandarin fish, and its morphological structure and partial biochemical and biophysical characteristics have been observed and analyzed. The isolated rhabdovirus has a typical bullet shape, and is therefore called S. chttatsi rhabdovirus (SCRV). And, the isolated rhabdovirus produced a higher titer (10(8.5) TCID50 ml(-1)) than did the co-infecting viruses (10(6.5) TCID50 ml(-1)). Subsequently, the viral genome RNA was extracted, and used as template to clone the complete nucleoprotein (N) gene by RT-PCR amplification. Cloning and sequencing of the SCRV N protein revealed 42%-31% amino acid identities to that of trout rhabdovirus 903/87 and the rhabdoviruses in genus Vesiculovirus. SDS-PAGE separation of the isolated SCRV and other two rhabdoviruses also revealed obvious polypeptide profile difference. Moreover, the anti-SCRV N protein antibody was prepared, and the anti-SCRV N protein antibody only could recognize the SCRV N protein, whereas no antigenicity was detected in other two rhabdoviruses. The data suggested that the SCRV should be a rhabdovirus member related to the genus Vesiculovirus in the Rhabdoviridae. (c) 2006 Elsevier B.V. All rights reserved.