In silico Structure Modeling and Comparative Analysis of Characterization Properties of Protein Polymers Useful for Protein-Based Nano Particulate Drug Delivery Systems (NPDDS): A Bioinformatics Approach

With an increasing interest in nanoparticulate delivery systems, there is a greater need to identify biomaterials that are biocompatible and safe for human applications. Protein polymers from animal and plant sources are promising materials for designing nanocarriers. Composition of the protein plays an important role for specific drug delivery applications such as drug release, targeting, and stimuli responsive drug release. An important issue in protein polymers is characteristics such as size, charge, and hydrophobicity may play a significant role in phagocytic uptake and initiating a subsequent immune response. This remains to be investigated systematically by analyzing factors that influence nanoparticle characteristics of protein and reduce phagocytic uptake and does not initiate immune response too. Although protein polymers are biodegradable, it is essential to ensure that there must not be premature enzymatic breakdown of the protein nanoparticles in the systemic circulation. Surface modification of the protein nanoparticles can be used to address this issue to propose the necessary modification in the surface of the protein would be great contribution in the nano particulate drug delivery systems (NPPDS). Of the various proteins, gelatin and albumin have been widely studied for drug delivery applications. Plant proteins are yet to be investigated widely for drug delivery applications so there is need to find out the plant proteins capable to act as nanoparticles. The commercial success of albumin-based nanoparticles has created an interest in other proteins. An increased understanding of the physicochemical properties coupled with the developments in rDNA technology will open up new opportunities for protein-based nanoparticulate systems. In the present studies several proteins currently useful for drug delivery system were structurally modeled and has been analyzed to propose the essential characteristics of protein for protein-based NPDDS.     

Anthrax biosensor, protective antigen ion channel asymmetric blockade

The significant threat posed by biological agents (e.g. anthrax, tetanus, botulinum, and diphtheria toxins) (Inglesby, T. V., O'Toole, T., Henderson, D. A., Bartlett, J. G., Ascher, M. S., Eitzen, E., Friedlander, A. M., Gerberding, J., Hauer, J., Hughes, J., McDade, J., Osterholm, M. T., Parker, G., Perl, T. M., Russell, P. K., and Tonat, K. (2002) J. Am. Med. Assoc. 287, 2236-2252) requires innovative technologies and approaches to understand the mechanisms of toxin action and to develop better therapies. Anthrax toxins are formed from three proteins secreted by fully virulent Bacillus anthracis, protective antigen (PA, 83 kDa), lethal factor (LF, 90 kDa), and edema factor (EF, 89 kDa). Here we present electrophysiological measurements demonstrating that full-length LF and EF convert the current-voltage relationship of the heptameric PA63 ion channel from slightly nonlinear to highly rectifying and diode-like at pH 6.6. This effect provides a novel method for characterizing functional toxin interactions. The method confirms that a previously well characterized PA63 monoclonal antibody, which neutralizes anthrax lethal toxin in animals in vivo and in vitro, prevents the binding of LF to the PA63 pore. The technique can also detect the presence of anthrax lethal toxin complex from plasma of infected animals. The latter two results suggest the potential application of PA63 nanopore-based biosensors in anthrax therapeutics and diagnostics.     

The discovery of the benzazepine class of histamine H3 receptor antagonists

This Letter describes the discovery of a novel series of H₃ receptor antagonists. The initial medicinal chemistry strategy focused on deconstructing and simplifying an early screening hit which rapidly led to the discovery of a novel series of H₃ receptor antagonists based on the benzazepine core. Employing an H₃ driven pharmacodynamic model, the series was then further optimised through to a lead compound that showed robust in vivo functional activity and possessed overall excellent developability properties.     

Pharmacology of Acorus calamus L

Water soluble dried powder of alcoholic extract of roots and rhizomes of A. calamus L. was used. The in vivo experiments involved strychnine convulsant activity in frogs, spontaneous motor activity and amphetamine hyperactivity in mice, pentobarbitone sleeping-time in rats and local anaesthetic activity in guinea pigs and rabbits. Frog skeletal muscle and heart preparations and rat phrenic nerve diaphragm constituted the in vitro experiments. Plant extracts at 10, 20 mg/kg ip did not afford protection to strychnine (1,5,2.5 mg/kg) induced convulsions and same effect was found on acetylcholine induced contractions of rectus muscle except that it inhibited caffeine citrate contractions in frog. At 1, 10 and 100 micrograms/ml doses, it caused negative iono- and chronotropic effects in frogs. Dosages of 10, 25, 50 mg/kg ip of herbal extract antagonize spontaneous motor activity and also amphetamine induced hyperactivity in mice. It was less potent than chloropromazine, though exerts sedative and tranquilizing action. Local anaesthetic activity was found to be absent at 0.5 and 1% dose levels.     

Fine mapping of the Schnyder’s crystalline corneal dystrophy locus

Schnyders crystalline corneal dystrophy (SCCD) is a rare autosomal dominant eye disease with a spectrum of clinical manifestations that may include bilateral corneal clouding, arcus lipoides, and anterior corneal crystalline cholesterol deposition. We have previously performed a genome-wide linkage analysis on two large Swede-Finn families and mapped the SCCD locus to a 16-cM interval between markers D1S2633 and D1S228 on chromosome 1p36. We have collected 11 additional families from Finland, Germany, Turkey, and USA to narrow the critical region for SCCD. Here, we have used haplotype analysis with densely spaced microsatellite markers in a total of 13 families to refine the candidate interval. A common disease haplotype was observed among the four Swede-Finn families indicating the presence of a founder effect. Recombination results from all 13 families refined the SCCD locus to 2.32 Mbp between markers D1S1160 and D1S1635. Within this interval, identity-by-state was present in all 13 families for two markers D1S244 and D1S3153, further refining the candidate region to 1.58 Mbp.     

Pore formation is not associated with macroscopic redistribution of P2X7 receptors

The present study examines whether changes in P2X7 purinergic receptor density precede formation of the cytolytic pore characteristic of this receptor. We fused P2X7 receptors with enhanced green fluorescent protein (EGFP) at the amino or carboxy termini (EGFP-P2X7 and P2X7-EGFP). Electrophysiological characterization in Xenopus oocytes revealed wild-type responses to ATP for GFP-tagged receptors. However, differences in sensitivity to ATP were apparent with the P2X7-EGFP receptor displaying a threefold reduction in ATP sensitivity compared with control. Ethidium ion uptake was used to measure cytolytic pore formation. Comparison of tagged receptors with wild type in HEK-293 and COS-7 cells showed there was no significant difference in ethidium ion uptake, suggesting that fusions with EGFP did not interfere with cytolytic pore formation. Confocal microscopy confirmed that tagged receptors localized to the plasmalemma. Simultaneous monitoring of EGFP and ethidium ion fluorescence revealed that changes in receptor distribution do not precede pore formation. We conclude that it is unlikely that large scale changes in P2X7 receptor density precede pore formation.     

Purification and Production of Novel Angiotensin I-Converting Enzyme (ACE) Inhibitory Bioactive Peptides Derived from Fermented Goat Milk

International Journal of Peptide Research and Therapeutics - In the study, five different Lactobacillus cultures i.e. L. rhamnosus (NK2) (KR080695), L. casei (NK9) (KR732325), L. fermentum (M5)...     

The automation of Nested Clade Phylogeographic Analysis

ANeCA is a fully automated implementation of Nested Clade Phylogeographic Analysis. This was originally developed by Templeton and colleagues, and has been used to infer, from the pattern of gene sequence polymorphisms in a geographically structured population, the historical demographic processes that have shaped its evolution. Until now it has been necessary to perform large parts of the procedure manually. We provide a program that will take data in Nexus sequential format, and directly output a set of inferences. The software also includes TCS v1.18 and GeoDis v2.2 as part of automation. Availability: The software is available free of charge from http://www.rubic.rdg.ac.uk/~mahesh/software.html. The program is written in Java and requires the Java 1.4 Runtime Environment (or later) to run. The source code is included in the package, and includes the source from TCS and GeoDis. ANeCA, TCS and GeoDis are released under the GNU General Public License.     

Phenotypic expression of Kluyveromyces lactis killer toxin against Saccharomyces spp.

The secretion of killer toxins by some strains of yeasts is a phenomenon of significant industrial importance. The activity of a recently discovered Kluyveromyces lactis killer strain against a sensitive Saccharomyces cerevisiae strain was determined on peptone-yeast extract-nutrient agar plates containing as the carbon source glucose, fructose, galactose, maltose, or glycerol at pH 4.5 or 6.5. Enhanced activity (50 to 90% increase) was found at pH 6.5, particularly on the plates containing galactose, maltose, or glycerol, although production of the toxin in liquid medium was not significantly different with either glucose or galactose as the carbon source. Results indicated that the action of the K. lactis toxin was not mediated by catabolite repression in the sensitive strain. Sensitivities of different haploid and polyploid Saccharomyces yeasts to the two different killer yeasts S. cerevisiae (RNA-plasmid-coded toxin) and K. lactis (DNA-plasmid-coded toxin) were tested. Three industrial polyploid yeasts sensitive to the S. cerevisiae killer yeast were resistant to the K. lactis killer yeast. The S. cerevisiae killer strain itself, however, was sensitive to the K. lactis killer yeast.