Role of neuraminic acid in the heterogeneity of alkaline phosphatase in sheep brain

1. Comparative studies of the polyuridylic acid-directed phenylalanine-incorporating activity of cell-free systems derived from rat and chicken livers demonstrated markedly lower activity in the chicken liver system. 2. The chicken liver cell sap contained the factor(s) responsible for this lower activity. Ribosomes from chicken and rat performed equally well in the presence of rat liver cell sap. Chicken liver cell sap, when mixed with rat liver cell sap, caused an inhibition of incorporation of phenylalanine into acid-insoluble material. 3. Though ribosomal preparations and cell sap from both rat and chicken liver degraded polyuridylic acid to some extent, the chicken liver cell sap contained the largest amount of activity. 4. Rat liver cell sap inhibited the nuclease activities of ribosomal preparations, but no such nuclease inhibition could be demonstrated with chicken liver cell sap.     

Histochemical localization of protein-polysaccharides in renal tissue

The purpose of this study was to investigate the distribution of protein-polysaccharides in the glomerular and non-glomerular regions of the nephron. The techniques used include the digestion of kidney slices with specific polysaccharidases: neuraminidase, hyaluronidase, chondroitinase ABC, and collagenase followed by several cytochemical techniques to identify the glycosaminoglycans and glycoproteins at the light and electron microscope levels. Differential staining of hyaluronic acid and sulphated glycosaminoglycans was accomplished with Alcian Blue at pH 2.5 and pH 0.5, respectively. Sialoproteins were stained with Alcian Blue at pH 2.5. The periodic acid Schiff’s reaction technique was employed for the visualization of collagen. At the electron microscope level the polysaccharides were identified with the periodic acid-chromic acid-silver methenamine reaction. Our results indicated that the major polysaccharide components of the glomerular basement membrane were sialoproteins and collagen, with smaller amounts of hyaluronic acid and various sulphated glycosaminoglycans. Hyaluronidase digestion resulted in partial detachment of epithelial processes from the glomerular basement membrane indicating the hyaluronic acid may have a role in the stability of the attachment of these processes. Tubular basement membranes also contain sialoproteins and sulphated glycosaminoglycans but in considerably lower concentrations than the glomerular basement membrane. Bowman’s capsule appears to contain mostly sulphated glycosaminoglycans and has a lower concentration of sialoproteins and hyaluronic acid.     

Green synthesis of ZnO nanoparticles for antimicrobial and vegetative growth applications: A novel approach for advancing efficient high quality health care to human wellbeing

The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV–vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved.     

The Structures of Bacteriorhodopsin With Different Retinal-Schiff Base Orientations - Computer Modeling And Energy Minimization Studies

Abstract

Bacteriorhodopsin has been the subject of intense study in order to understand its photochemical function. The recent atomic model proposed by Henderson and coworkers based on electron cryo-microscopic studies has helped in understanding many of the structural and functional aspects of bacteriorhodopsin. However, the accuracy of the positions of the side chains is not very high since the model is based on low-resolution data. In this study, we have minimized the energy of this structure of bacteriorhodopsin and analyzed various types of interactions such as - intrahelical and interhelical hydrogen bonds and retinal environment. In order to understand the photochemical action, it is necessary to obtain information on the structures adopted at the intermediate states. In this direction, we have generated some intermediate structures taking into account certain experimental data, by computer modeling studies. Various isomers of retinal with 13-cis and/or 15-cis conformations and all possible staggered orientations of Lys-216 side chain were generated. The resultant structures were examined for the distance between Lys-216-schiff base nitrogen and the carboxylate oxygen atoms of Asp- 96 - a residue which is known to reprotonate the schiffbase at later stages of photocycle. Some of the structures were selected on the basis of suitable retinal orientation and the stability of these structures were tested by energy minimization studies. Further, the minimized structures are analyzed for the hydrogen bond interactions and retinal environment and the results are compared with those of the minimized rest state structure. The importance of functional groups in stabilizing the structure of bacteriorhodopsin and in participating dynamically during the photocycle have been discussed.     

Probing the effect of nitro groups in nitramine based energetic molecules: a DFT and charge density study

The structure, electron density distribution, energetic and electrostatic properties of simple nitramine based energetic TMA, DMNA, MDA and TNA molecules were determined using density functional theory (B3LYP) with the 6-311G^** and aug-cc-pVDZ basis sets coupled with Bader's theory of atoms in molecules. In the NO₂ group substituted molecules, the N–N bond distance increases with the increase of NO₂ groups, whereas in C–N bonds, this effect is relatively less, and the distances are almost equal. The topological analysis of electron density reveals that the electron density ρ_bcp(r) of C–N and N–N bonds are significantly decreasing with the increase of NO₂ groups in the nitramine molecules. The Laplacian of electron density ▽²ρ_bcp(r) of N–NO₂ bonds [DMNA: ? 16.7 eÅ^? 5, MDA: ? 12.8 eÅ^? 5 and TNA: ? 7.9 eÅ^? 5] of the molecules are relatively less negative, and the values also decrease with the increase of NO₂ groups; this implies that the charge concentration decreases with the increase of NO₂ groups, which leads to weakening the N–N bonds of the molecules. The isosurface of molecular electrostatic potential displays high electronegative regions around the NO₂ groups. The oxygen balance OB₁₀₀ of the molecules increases as the number of NO₂ group increases in the molecules, in which, the TNA molecule having maximum OB₁₀₀ value [+7.89]. The band gap, heat of detonation, bond dissociation energy and charge imbalance are predominantly depends on the number of NO₂ group present in the molecule. The charge imbalance parameter (ν) has been calculated for all molecules, which reveals that TNA is a highly sensitive molecule, the corresponding ν value is 0.047.     

Stability and dynamics of domain-swapped bovine-seminal ribonuclease

The proteins of the ribonuclease-A (RNase-A) family are monomeric, with the exception of bovine-seminal ribonuclease (BS-RNase). BS-RNase is formed by swapping the N-terminal helices across the two monomeric units. A molecular-dynamics (MD) study has been performed on the protein for a simulation time of 5.5 ns to understand the factors responsible for the stability of the dimer. Essential dynamics analysis and motional correlation of the protein atoms yielded the picture of a stabilising, yet flexible, interface. We have investigated the role of intermolecular H-bonding, protein/water interaction, and protein/water networks in stabilising the dimer. The networks of interchain H-bonds involving side-chain/side-chain or side-chain/main-chain (ScHB) interactions between the two chains have also been studied. The ability of protein atoms in retaining particular H2O molecules was investigated as a function of the accessible surface area (ASA), depth, and hydration parameters, as well as their participation in protein/water networks.     

Management of root-knot nematode in tomato Lycopersicon esculentum,Mill, with biogas slurry

The effect of biogas slurry application on the severity of root-knot nematode, Meloidogyne incognita, attack on tomato cv. Co-1, was tested in the green house with two levels of biogas slurry: 5% and 10% (w/w) added to soil. Both the number (3 fruits/plant) and fruit yield (35.2 g/plant) of tomato increased significantly with 10% (w/w) biogas slurry. The plants amended with biogas slurry put up more vegetative growth and tended to flower and fruit much earlier than did those of the control. The nematode population in the soil decreased thus decreasing the severity of nematode attack.