The Ebola Virus Matrix Protein VP40 Selectively Induces Vesiculation from Phosphatidylserine-enriched Membranes

Ebola virus is from the Filoviridae family of viruses and is one of the most virulent pathogens known with ∼60% clinical fatality. The Ebola virus negative sense RNA genome encodes seven proteins including viral matrix protein 40 (VP40), which is the most abundant protein found in the virions. Within infected cells VP40 localizes at the inner leaflet of the plasma membrane (PM), binds lipids, and regulates formation of new virus particles. Expression of VP40 in mammalian cells is sufficient to form virus-like particles that are nearly indistinguishable from the authentic virions. However, how VP40 interacts with the PM and forms virus-like particles is for the most part unknown. To investigate VP40 lipid specificity in a model of viral egress we employed giant unilamellar vesicles with different lipid compositions. The results demonstrate VP40 selectively induces vesiculation from membranes containing phosphatidylserine (PS) at concentrations of PS that are representative of the PM inner leaflet content. The formation of intraluminal vesicles was not significantly detected in the presence of other important PM lipids including cholesterol and polyvalent phosphoinositides, further demonstrating PS selectivity. Taken together, these studies suggest that PM phosphatidylserine may be an important component of Ebola virus budding and that VP40 may be able to mediate PM scission.     

Isolation and Characterization of a Nitrile-Hydrolysing Bacterium Isoptericola variabilis RGT01

A nitrile-hydrolysing bacterium, identified as Isoptericola variabilis RGT01, was isolated from industrial effluent through enrichment culture technique using acrylonitrile as the carbon source. Whole cells of this microorganism exhibited a broad range of nitrile-hydrolysing activity as they hydrolysed five aliphatic nitriles (acetonitrile, acrylonitrile, propionitrile, butyronitrile and valeronitrile), two aromatic nitriles (benzonitrile and m-Tolunitrile) and two arylacetonitriles (4-Methoxyphenyl acetonitrile and phenoxyacetonitrile). The nitrile-hydrolysing activity was inducible in nature and acetonitrile proved to be the most efficient inducer. Minimal salt medium supplemented with 50 mM acetonitrile, an incubation temperature of 30 °C with 2 % v/v inoculum, at 200 rpm and incubation of 48 h were found to be the optimal conditions for maximum production (2.64 ± 0.12 U/mg) of nitrile-hydrolysing activity. This activity was stable at 30 °C as it retained around 86 % activity after 4 h at this temperature, but was thermolabile with a half-life of 120 min and 45 min at 40 °C and 50 °C respectively.     

A study of C-reactive protein,lipid metabolism and peripheral blood to identify a link between periodontitis and cardiovascular disease

Periodontitis is characterized by systemic inflammatory host responses that may contribute to a higher risk for cardiovascular disease. We hypothesized that periodontitis may be associated with altered C-reactive protein levels, serum levels of lipids and peripheral blood counts, and that these characteristics may serve as markers for a link between periodontitis and cardiovascular disease. Sixty subjects, 25–60 years old, were divided into three groups of 20 subjects each. Group 1, age and sex matched healthy controls; group 2, patients diagnosed with chronic periodontitis; group 3, patients diagnosed with acute periodontal lesions including periodontal abscess and pericoronal abscesses. Serum C-reactive protein levels, lipid levels and peripheral blood counts were obtained for all three groups. Significant increases in C-reactive protein and serum lipid levels, and altered peripheral blood counts were observed between the experimental groups; these factors were correlated with chronic periodontitis and cardiovascular disease. These simple, economical clinical measurements can be used to assess periodontal tissue damage and may be useful for predicting risk of cardiovascular disease in these subjects.     

Characterization of Soy Polysaccharide and Its In Vitro and In Vivo Evaluation for Application in Colon Drug Delivery

The objective of the present investigation was to establish potential of commercially available soy polysaccharide (Emcosoy®) for colon drug delivery. The soy polysaccharide–ethyl cellulose films were fabricated and characterized. The effect of the pectinase enzyme on the tensile strength and surface morphology of the film was evaluated. The permeation of chlorpheniramine maleate (CPM), a model hydrophilic drug from pectinase enzyme treated and untreated films was measured in pH 7.4 buffer. The soy polysaccharide–ethyl cellulose films were also incubated with Lactobacillus sp. culture for a specific duration, and effect on the CPM permeation was evaluated. The CPM capsules were coated with the soy polysaccharide–ethyl cellulose mixture, and Eudragit S100 was applied as a secondary coat. The coated CPM capsules were radiolabelled, and their in vivo transit was evaluated in human volunteers on oral administration. The pectinase enzyme had a significant influence on the tensile strength and surface morphology of the soy polysaccharide–ethyl cellulose films. The permeability of pectinase enzyme-treated and Lactobacillus sp.-treated films was significantly higher than that of untreated films. The CPM capsules were coated with the soy polysaccharide–ethyl cellulose mixture and Eudragit S100 and were successfully radiolabelled by a simple method. Gamma scintigraphic studies in human volunteers showed that the radiolabelled capsules maintained integrity for at least 9 h after oral administration. Thus, the soy polysaccharide has a potential in colon drug delivery.     

pH-dependent Soret difference spectra of the deoxy and carbonmonoxy forms of human hemoglobin and its derivatives.

The transition from deoxy to oxystructure of hemoglobin A (Hb) is accompanied by the breaking of the salt bridges formed by C-terminal residues in deoxy-Hb. This, in turn, changes the state of the heme. The switch between these different allosteric forms can be followed by changes in the optical absorbance spectra (Perutz, M. F., Ladner, J. E., Simon, S. R., and Ho, C. (1974), Biochemistry 13, 2163). Using difference spectroscopy in the soret region, pH-dependent spectral changes of Hb and its derivatives (carbamylated at both the alpha-NH2 groups, alpha2cbeta2c; N-ethylsuccinimide hemoglobin, NES-Hb) in their deoxy and carbonmonoxy forms were measured. From these measurements, the pK values of histidine-146beta and valine-1alpha in deoxy-Hb were determined to be 8.6 +/- 0.2 and 7.7 +/- 0.1, respectively. In carbonmonoxy-Hb a pK value of 6.3 +/- 0.1 was found.     

Interaction of aliphatic cap group in inhibition of histone deacetylases by cyclic tetrapeptides

Inhibitors of histone deacetylases (HDACs) are a promising class of anticancer agents that effect gene regulation. To know the interaction of aliphatic cap groups with HDACs, cyclic tetrapeptide and bicyclic peptide disulfide hybrids were synthesized without aromatic ring in their macrocyclic framework. Benzene ring of l-Phe in chlamydocin was replaced with several aliphatic amino acids and also a fused bicyclic tetrapeptide was synthesized by ring closing metathesis using Grubb's first generation catalyst. The inhibitory activities of the cyclic peptides against histone deacetylase enzymes were evaluated, which demonstrated most of them are interesting candidates as anticancer agents.     

Comparative biodegradation of HDPE and LDPE using an indigenously developed microbial consortium

A variety of bacterial strains were isolated from waste disposal sites of Uttaranchal, India, and some from artificially developed soil beds containing maleic anhydride, glucose, and small pieces of polyethylene. Primary screening of isolates was done based on their ability to utilize high- and low-density polyethylenes (HDPE/LDPE) as a primary carbon source. Thereafter, a consortium was developed using potential strains. Furthermore, a biodegradation assay was carried out in 500-ml flasks containing minimal broth (250 ml) and HDPE/ LDPE at 5 mg/ml concentration. After incubation for two weeks, degraded samples were recovered through filtration and subsequent evaporation. Fourier transform infrared spectroscopy (FTIR) and simultaneous thermogravimetric-differential thermogravimetry-differential thermal analysis TG-DTG-DTA) were used to analyze these samples. Results showed that consortium-treated HDPE (considered to be more inert relative to LDPE) was degraded to a greater extent 22.41% weight loss) in comparison with LDPE (21.70% weight loss), whereas, in the case of untreated samples, weight loss was more for LDPE than HDPE (4.5% and 2.5%, respectively) at 400 degrees . Therefore, this study suggests that polyethylene could be degraded by utilizing microbial consortia in an eco-friendly manner.