Functional assignment to JEV proteins using SVM

Identification of different protein functions facilitates a mechanistic understanding of Japanese encephalitis virus (JEV) infection and opens novel means for drug development. Support vector machines (SVM), useful for predicting the functional class of distantly related proteins, is employed to ascribe a possible functional class to Japanese encephalitis virus protein. Our study from SVMProt and available JE virus sequences suggests that structural and nonstructural proteins of JEV genome possibly belong to diverse protein functions, are expected to occur in the life cycle of JE virus. Protein functions common to both structural and non-structural proteins are iron-binding, metal-binding, lipid-binding, copper-binding, transmembrane, outer membrane, channels/Pores - Pore-forming toxins (proteins and peptides) group of proteins. Non-structural proteins perform functions like actin binding, zinc-binding, calcium-binding, hydrolases, Carbon-Oxygen Lyases, P-type ATPase, proteins belonging to major facilitator family (MFS), secreting main terminal branch (MTB) family, phosphotransfer-driven group translocators and ATP-binding cassette (ABC) family group of proteins. Whereas structural proteins besides belonging to same structural group of proteins (capsid, structural, envelope), they also perform functions like nuclear receptor, antibiotic resistance, RNA-binding, DNA-binding, magnesium-binding, isomerase (intra-molecular), oxidoreductase and participate in type II (general) secretory pathway (IISP).     

Changes in the levels of superoxide anion radical and superoxide dismutase during the estrous cycle of Rattus norvegicus and induction of superoxide dismutase in rat ovary by lutropin

Superoxide dismutase, which has been shown to be present in a number of tissues, exhibits cyclic changes during the reproductive cycle of rats. An inverse correlation is seen between the levels of superoxide dismutase and superoxide radical. In immature, pseudopregnant rats, primed with human Chorionic Gonadotropin, lutropin seemed to induce ovarian superoxide dismutase, which could be blocked significantly by the introduction of anti-LH serum. These results point out the specific induction of superoxide dismutase by lutropin. It is reasonable to postulate that during luteal functioning, luteinizing hormone induces superoxide dismutase which in turn seems to play a central role generating hydrogen peroxide from superoxide anion radicals. Hydrogen peroxide, thus formed, drives the peroxidase-ascorbate system, responsible for production of progesterone.     

Expression of 93D heat shock puff of Drosophila melanogaster in deficiency genotypes and its influence on activity of the 87C puff

Using the overlapping deficiencies Df(3R)GC14 and Df(3R)e ^Gp 4 of the 93D region of Drosophila melanogaster, the benzamide (BM)-inducible site in polytene chromsomes was localised to the 93D6-7 region, which had earlier been identified as heat inducible. The normal developmental and BM-induced 93D6-7 puff was found to be dosage compensated since in larvae heterozygotus for a deficiency, with one dose of 93D6-7, the rate of ³H-uridine incorporation in this puff was the same as in the wild type with two doses. Curiously, however, heat shock (37° C) caused regression of the 93D6-7 puff on the normal chromosome in heterozygotes. In agreement with earlier results from our laboratory, the non-inducibility of the single-dose 93D locus by heat shock in the heterozygotes, caused the 87C puff to be nearly half as active as the 87A puff at 37° C. However, in e ^Gp 4/GC14 larvae, lacking the 93D6-7 locus on both homologues, the 87C puff was less active than 87A in some heat-shocked larvae but in other larvae 87A and 87C were equally active. Possible reasons for this inter-larval variability are discussed.     

The topography of glycerophosphate acyltransferase in the transverse plane of the mitochondrial outer membrane

In low ionic media, mitochondrial glycerophosphate acyltransferase was inhibited virtually completely within 15 min by the nonspecific proteases, proteinase K and subtilisin. In high ionic media, the mitochondrial enzyme was either not inhibited or was marginally inhibited by these proteases. Chymotrypsin and trypsin, regardless of the ionic strength of the medium, did not inhibit the acyltransferase. Substantial inhibition by proteinase K and subtilisin was observed in the high ionic media when the incubation was continued for 30 or 45 min. Adenylate kinase, an intermembrane enzyme, was not inhibited under any of the above conditions. These results demonstrate a cytosolic exposure of the mitochondrial acyltransferase. In a low ionic environment, when the outer membrane integrity was damaged either by gradually decreasing the tonicity of the medium or by stepwise addition of Triton X-100, either chymotrypsin or trypsin caused virtually parallel inhibition of glycerophosphate acyltransferase and adenylate kinase. A more direct approach in establishing the existence of protease-susceptible sites on the inner side of the outer membrane was taken by observing the inhibition of mitochondrial glycerophosphate acyltransferase and adenylate kinase in trypsinloaded right-side-out outer membrane vesicles incubated in the presence of externally located soybean trypsin inhibitor. The above results, taken together, suggest that mitochondrial glycerophosphate acyltransferase spans the transverse plane of the outer membrane.     

The site of synthesis of mitochondrial proteins in Krebs II ascites-tumour cells

At 22° in Earle's medium, Krebs cells synthesize proteins. After a brief `pulse' with [<sup>14</sup>C]valine followed by a `chase' of [¹²C]valine the radioactivity appears first in microsomes and is transferred after `chase' to the cell sap. Kinetics of labelling of the mitochondrial protein are different from that of either microsomal or cell-sap protein. When Krebs cells in buffer are mixed with ribonuclease in water the nuclease penetrates the cell membrane. The ribonuclease-treated cells are still viable but have lost most of their cytoplasmic ribosomes (electron micrograph). Such cells still synthesize mitochondrial protein at near normal rate but synthesis of microsomal protein is severely inhibited. The results indicate that some mitochondrial proteins are synthesized independently of the microsome–cell-sap system.     

Trypsin inhibitors from ridged gourd (Luffa acutangula Linn.) seeds: Purification, properties, and amino acid sequences

Two trypsin inhibitors, LA-1 and LA-2, have been isolated from ridged gourd (Luffa acutangula Linn.) seeds and purified to homogeneity by gel filtration followed by ion-exchange chromatography. The isoelectric point is atpH 4.55 for LA-1 and atpH 5.85 for LA-2. The Stokes radius of each inhibitor is 11.4 å. The fluorescence emission spectrum of each inhibitor is similar to that of the free tyrosine. The biomolecular rate constant of acrylamide quenching is 1.0×10⁹ M^–1 sec^–1 for LA-1 and 0.8 × 10⁹ M^–1 sec^–1 for LA-2 and that of K₂HPO₄ quenching is 1.6×10¹¹ M^–1 sec^–1 for LA-1 and 1.2×10¹¹M^–1 sec^–1 for LA-2. Analysis of the circular dichroic spectra yields 40%-helix and 60%-turn for La-1 and 45%-helix and 55%-turn for LA-2. Inhibitors LA-1 and LA-2 consist of 28 and 29 amino acid residues, respectively. They lack threonine, alanine, valine, and tryptophan. Both inhibitors strongly inhibit trypsin by forming enzymeinhibitor complexes at a molar ratio of unity. A chemical modification study suggests the involvement of arginine of LA-1 and lysine of LA-2 in their reactive sites. The inhibitors are very similar in their amino acid sequences, and show sequence homology with other squash family inhibitors.     

Nano-biotechnology in tumour and cancerous disease: A perspective review

In recent years, drug manufacturers and researchers have begun to consider the nanobiotechnology approach to improve the drug delivery system for tumour and cancer diseases. In this article, we review current strategies to improve tumour and cancer drug delivery, which mainly focuses on sustaining biocompatibility, biodistribution, and active targeting. The conventional therapy using cornerstone drugs such as fludarabine, cisplatin etoposide, and paclitaxel has its own challenges especially not being able to discriminate between tumour versus normal cells which eventually led to toxicity and side effects in the patients. In contrast to the conventional approach, nanoparticle-based drug delivery provides target-specific delivery and controlled release of the drug, which provides a better therapeutic window for treatment options by focusing on the eradication of diseased cells via active targeting and sparing normal cells via passive targeting. Additionally, treatment of tumours associated with the brain is hampered by the impermeability of the blood–brain barriers to the drugs, which eventually led to poor survival in the patients. Nanoparticle-based therapy offers superior delivery of drugs to the target by breaching the blood–brain barriers. Herein, we provide an overview of the properties of nanoparticles that are crucial for nanotechnology applications. We address the potential future applications of nanobiotechnology targeting specific or desired areas. In particular, the use of nanomaterials, biostructures, and drug delivery methods for the targeted treatment of tumours and cancer are explored.     

Evaluation of anti-inflammatory activity of Vernonia cinerea Less. extract in rats.

The methanol extract of the whole plant of Vernonia cinerea Less. was evaluated for its anti-inflammatory activity in acute (carrageenin, histamine and serotonin induced rat paw edema) and a chronic model (cotton pouch induced granuloma). The methanol extract (250 and 500 mg/kg(-1) p.o.) exhibited significant activity (p < 0.001) against all phlogistic agents used in a dose dependant manner. In the chronic model (cotton pouch granuloma method) the methanol extract exhibited significant anti-inflammatory activity. All these effects were compared with standard drug phenylbutazone (100 mg/kg(-1) p.o.).     

Trypsin inhibitors from ridged gourd (Luffa acutangula Linn.) seeds: Purification,properties, and amino acid sequences

Two trypsin inhibitors, LA-1 and LA-2, have been isolated from ridged gourd (Luffa acutangula Linn.) seeds and purified to homogeneity by gel filtration followed by ion-exchange chromatography. The isoelectric point is atpH 4.55 for LA-1 and atpH 5.85 for LA-2. The Stokes radius of each inhibitor is 11.4 å. The fluorescence emission spectrum of each inhibitor is similar to that of the free tyrosine. The biomolecular rate constant of acrylamide quenching is 1.0×10⁹ M^?1 sec^?1 for LA-1 and 0.8 × 10⁹ M^?1 sec^?1 for LA-2 and that of K₂HPO₄ quenching is 1.6×10¹¹ M^?1 sec^?1 for LA-1 and 1.2×10¹¹M^?1 sec^?1 for LA-2. Analysis of the circular dichroic spectra yields 40%α-helix and 60%Β-turn for La-1 and 45%α-helix and 55%Β-turn for LA-2. Inhibitors LA-1 and LA-2 consist of 28 and 29 amino acid residues, respectively. They lack threonine, alanine, valine, and tryptophan. Both inhibitors strongly inhibit trypsin by forming enzymeinhibitor complexes at a molar ratio of unity. A chemical modification study suggests the involvement of arginine of LA-1 and lysine of LA-2 in their reactive sites. The inhibitors are very similar in their amino acid sequences, and show sequence homology with other squash family inhibitors.