Optimization of nutrients for the production of RNase by <Emphasis Type="Italic">Bacillus firmus</Emphasis> VKPACU1 using response surface methodology

Medium optimization for the nuclease (RNase) production by Bacillus firmus VKPACU-1 was studied using the one-factor-at-a-time method and Response Surface Methodology (RSM). One-factor-at-a-time methodology was used to study the effects of carbon, nitrogen, phosphorus sources, and physical conditions such as pH and temperature, on nuclease (RNase) production. After optimizing the carbon (glucose) and nitrogen (tryptone) sources in the culture medium the physical conditions, pH (6.5) and temperature (35°C) were also optimized. Later these conditions were chosen as the main factors and used in the experimental design. The central composite design (CCD) of the RSM was employed to evaluate the interactive effects of these four variables. The optimized values obtained by the statistical analysis showed that glucose 5.95 g/L, tryptone 22.5 g/L, pH 6.5, and temperature 35°C affected maximum nuclease (RNase) production. When utilizing these proposed optimized conditions, the model predicted nuclease (RNase) production of 43.6 U/mL and in the validation experiments, the nuclease production obtained was 46.5 U/mL. The nuclease production in medium optimized by RSM was 26% higher, than in the non-optimized medium.     

Biopotential of Fleuggea leucopyrus (Koen.) Willd. against Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

In the past five decades, agricultural pests are controlled by synthetic pesticides which caused ill effects on non-target organisms and environment; also insect pests developed resistance and minor pests became major pests. By keeping this in mind, the present study was selected. Antifeedant and larvicidal activities and growth inhibitory effects of hexane, chloroform and ethyl acetate leaf extracts of Fleuggea leucopyrus (Koen.) Willd. against Helicoverpa armigera (Hbn.) were studied. Antifeedant and larvicidal activities were evaluated at 0.5, 1, 2.5 and 5% concentrations at laboratory conditions. Hexane and chloroform extracts at 5% concentration recorded significant antifeedant activity of 82.41 and 74.45%, respectively. Hexane extract recorded the least LC₅₀ and LC₉₀ values of 1.37 and 4.80%, respectively. Hexane extract recorded maximum larvicidal activity of 85.78% with LC₅₀ and LC₉₀ values of 1.69 and 4.94%, respectively. Ethyl acetate extract also had notable amount of larvicidal activity of 81.77% at 5% concentration. Hexane extract at 5 and 2.5% and ethyl acetate extract at 5% concentrations completely prevented the adult emergence of H. armigera. This plant could be further exploited to identify the active principle(s) responsible for the activities and to develop a novel pesticidal formulation. This is the first report of F. leucopyrus is studied for its bioefficacy against H. armigera.     

Textural characterization of histopathological images for oral sub-mucous fibrosis detection

In the field of quantitative microscopy, textural information plays a significant role very often in tissue characterization and diagnosis, in addition to morphology and intensity. The aim of this work is to improve the classification accuracy based on textural features for the development of a computer assisted screening of oral sub-mucous fibrosis (OSF). In fact, a systematic approach is introduced in order to grade the histopathological tissue sections into normal, OSF without dysplasia and OSF with dysplasia, which would help the oral onco-pathologists to screen the subjects rapidly. In totality, 71 textural features are extracted from epithelial region of the tissue sections using various wavelet families, Gabor-wavelet, local binary pattern, fractal dimension and Brownian motion curve, followed by preprocessing and segmentation. Wavelet families contribute a common set of 9 features, out of which 8 are significant and other 61 out of 62 obtained from the rest of the extractors are also statistically significant (p < 0.05) in discriminating the three stages. Based on mean distance criteria, the best wavelet family (i.e., biorthogonal3.1 (bior3.1)) is selected for classifier design. support vector machine (SVM) is trained by 146 samples based on 69 textural features and its classification accuracy is computed for each of the combinations of wavelet family and rest of the extractors. Finally, it has been investigated that bior3.1 wavelet coefficients leads to higher accuracy (88.38%) in combination with LBP and Gabor wavelet features through three-fold cross validation. Results are shown and discussed in detail. It is shown that combining more than one texture measure instead of using just one might improve the overall accuracy.     

Native N-Terminus Nitrophorin 2 from the Kissing Bug: Similarities to and Differences from NP2(D1A)

The first amino acid of mature native nitrophorin 2 is aspartic acid, and when expressed in E. coli, the wild-type gene of the mature protein retains the methionine-0, which is produced by translation of the start codon. This form of NP2, (M0)NP2, has been found to have different properties from its D1A mutant, for which the Met0 is cleaved by the methionine aminopeptidase of E. coli (R.?E. Berry, T.?K. Shokhireva, I. Filippov, M.?N. Shokhirev, H. Zhang, F.?A. Walker, Biochemistry 2007, 46, 6830). Native N-terminus nitrophorin 2 ((ΔM0)NP2) has been prepared by employing periplasmic expression of NP2 in E. coli using the pelB leader sequence from Erwinia carotovora, which is present in the pET-26b expression plasmid (Novagen). This paper details the similarities and differences between the three different N-terminal forms of nitrophorin 2, (M0)NP2, NP2(D1A), and (ΔM0)NP2. It is found that the NMR spectra of high- and low-spin (ΔM0)NP2 are essentially identical to those of NP2(D1A), but the rate and equilibrium constants for histamine and NO dissociation/association of the two are different.     

Density functional theory and ab initio studies of vibrational spectra of 2-bis (2-chloroethyl) aminoperhydro-1,3,2-oxazaphosphorinane-2-oxide

The Fourier transform Raman (FTR) and Fourier transform infrared (FTIR) spectra of 2-bis (2-chloroethyl) aminoperhydro-1,3,2-oxazaphosphorinane-2-oxide were recorded in the regions 4000–100 cm^? 1 and 4000–400 cm¹, respectively, in the solid phase. Molecular electronic energy, geometrical structure, harmonic vibrational spectra, infrared intensities and Raman scattering activities, highest occupied molecular orbital, lowest unoccupied molecular orbital energy, energy gaps and thermodynamical properties such as zero-point vibrational energies, rotational constants, entropies and dipole moment were computed at the Hartree–Fock/6-31G(d,p) and three parameter hybrid functional Lee–Yang–Parr/6-31G(d,p) levels of theory. The vibrational studies were interpreted in terms of potential energy distribution. The results were compared with experimental values with the help of scaling procedures. The observed wave number in FTIR and FTR spectra was analysed and assigned to different normal modes of the molecule. Most of the modes have wave numbers in the expected range and are in good agreement with computed values.     

Disulfiram Suppresses Growth of the Malignant Pleural Mesothelioma Cells in Part by Inducing Apoptosis

Dithiocarbamate compound Disulfiram (DSF) that binds with copper and functions as an inhibitor of aldehyde dehydrogenase is a Food and Drug Administration approved agent for treatment of alcoholism. Copper complexed DSF (DSF-Cu) also possesses anti-tumor and chemosensitizing properties; however, its molecular mechanisms of action remain unclear. Here we investigated malignant pleural mesothelioma (MPM) suppressive effects of DSF-Cu and the molecular mechanisms involved. DSF-Cu inhibited growth of the murine as well as human MPM cells in part by increasing levels of ubiquitinated proteins. DSF-Cu exposure stimulated apoptosis in MPM cells that involved activation of stress-activated protein kinases (SAPKs) p38 and JNK1/2, caspase-3, and cleavage of poly-(ADP-ribose)-polymerase, as well as increased expression of sulfatase 1 and apoptosis transducing CARP-1/CCAR1 protein. Gene-array based analyses revealed that DSF-Cu suppressed cell growth and metastasis-promoting genes including matrix metallopeptidase 3 and 10. DSF inhibited MPM cell growth and survival by upregulating cell cycle inhibitor p27Kip1, IGFBP7, and inhibitors of NF-κB such as ABIN 1 and 2 and Inhibitory κB (IκB)α and β proteins. DSF-Cu promoted cleavage of vimentin, as well as serine-phosphorylation and lysine-63 linked ubiquitination of podoplanin. Administration of 50 mg/kg DSF-Cu by daily i.p injections inhibited growth of murine MPM cell-derived tumors in vivo. Although podoplanin expression often correlates with metastatic disease and poor prognosis, phosphorylation of serines in cytoplasmic domain of podoplanin has recently been shown to interfere with cellular motility and migration signaling. Post-translational modification of podoplanin and cleavage of vimentin by DSF-Cu underscore a metastasis inhibitory property of this agent and together with our in vivo studies underscore its potential as an anti-MPM agent.     

Molecular dynamics simulation of the <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> YsxC protein: molecular insights into ribosome assembly and allosteric inhibition of the protein

YsxC from Staphylococcus aureus is a member of the GTPase protein family, and is involved in the ribosomal assembly and stability of this microorganism through its interactions with the L17, S2 and S10 ribosomal proteins. Inhibition of its interactions with L17, S2, S10 and the β′ subunit of RNA polymerase influences ribosomal assembly, which may affect the growth of the microorganism. This makes YsxC a novel target for the design of inhibitors to treat the disease caused by S. aureus. Understanding the interaction mechanism between YsxC and its partners would aid in the identification of potential catalytic residues, which could then be targeted to inhibit its function. Accordingly, in the present study, an in silico analysis of the interactions between YsxC and L17, S2 and S10 was performed, and the potential residues involved in these interactions were identified. Based on the simulation results, a possible mechanism for the interactions between these proteins was also proposed. Finally, six ligands from among a library of 81,000 chemical molecules were found to interact with parts of the G2 and switch II regions of the YsxC protein. Moreover, their interactions with the YsxC protein were observed to provoke changes at its GTP-binding site, which suggests that the binding of these ligands leads to a reduction in GTPase activity, and they were also found to affect the interactions of YsxC with its partners. This observation indicates that the proposed interacting site of YsxC may act as an allosteric site, and disrupting interactions at this site might lead to novel allosteric inhibition of the YsxC protein.     

High-frequency shoot regeneration from leaf explants through organogenesis in bitter melon (<Emphasis Type="Italic">Momordica charantia</Emphasis> L.)

An efficient protocol for in vitro organogenesis was achieved from callus-derived immature and mature leaf explants of Momordica charantia, a very important vegetable and medicinal plant. Calluses were induced from immature leaf explants excised from in vitro (15-day-old seedlings) mature leaf explants of vivo plants (45 days old). The explants were grown on Murashige and Skoog (MS) medium with Gamborg (B5) vitamins containing 30 g l⁻¹ sucrose, 2.2 g l⁻¹ Gelrite, and 7.7 μM naphthalene acetic acid (NAA) with 2.2 μM thidiazuron (TDZ). Regeneration of adventitious shoots from callus (30–40 shoots per explant) was achieved on MS medium containing 5.5 μM TDZ, 2.2 μM NAA, and 3.3 μM silver nitrate (AgNO₃). The shoots (1.0 cm length) were excised from callus and elongated in MS medium fortified with 3.5 μM gibberellic acid (GA₃). The elongated shoots were rooted in MS medium supplemented with 4.0 μM indole 3-butyric acid (IBA). Rooted plants were acclimatized in the greenhouse and subsequently established in soil with a survival rate of 90%. This protocol yielded an average of 40 plants per leaf explant with a culture period of 98 days.     

Effect of Ca2+ on the self assembly of a nonionic peptide aggregate

Conductometry, circular dichroism and fluorescence spectroscopy are thetechniques employed to investigate the effect of added calcium ions and other monovalent and divalent metal ions on aqueous solutions of nonionic peptide aggregates, Boc-Leu-Asn-OEt (1). It is observed that among all the metal ions studied, Ca²⁺ ions facilitate the aggregation of the peptide. The interior dielectric constant of the micelles () was found to depend upon the proportion of Ca²⁺ complexed peptide with the peptide monomers in the micelles. When Ca²⁺ ion becomes 1/4th of the peptide concentration, there is a structural transition leading to drastic change in the interior of the micro dielectric constant (_m).