Gravimetric Estimation of Mn(II) with Sodium Benzilate

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Structural characterization of the <i style="">O</i>-antigenic polysaccharide from the lipopolysaccharide of <i style="">Vibrio</i> <i style="">cholerae</i> <i style="">O</i>37

729-734 The chemical structure of the O-antigenic polysaccharide isolated from the lipopolysaccharide of Vibrio cholerae O37 by mild acid hydrolysis was elucidated. The O-antigenic polysac­charide is found to consist of D-glucose, N-acetyl-D-Quinovos­amine and small amount of 4-O-methyl-N-acetyl-D-quinovas­amine. The structure of the O-antigen is established by using sugar and methylation analyses, Smith degradation studies and by using GLC, GC-MS, FAB-MS, one dimensional 1H and 13C NMR spectroscopy and two dimensional NMR spectroscopy including COSY, TOCSY, HSQC, experiments. </smarttagtype

Extracellular Polysaccharides of a Copper-Sensitive and a Copper-Resistant Pseudomonas Aeruginosa Strain: Synthesis, Chemical Nature and Copper Binding

Extracellular polysaccharides (EPS) of a copper-sensitive (Cus) and a copper-resistant (Cur) Pseudomonas aeruginosa strain were investigated in terms of their production, chemical nature and response towards copper exposure. The extent of EPS synthesis by the resistant strain (4.78 mg mg)1 cell dry wt.) was considerably higher over its sensitive counterpart (2.78 mg mg)1 dry wt.). FTIR-spectroscopy and gas chromatography revealed that both the polymers were acidic in nature, containing alginate as the major component along with various neutraland amino-sugars. Acid content in the Cur EPS (480.54 mg g)1) was greater than that in the Cus EPS (442.0mg g)1). Presence of Cu2þ in the growth medium caused a dramatic stimulation (approximately 4-fold) in EPS synthesis by the Cur strain, while in a similar condition, the Cus failed to exhibit such response. The polymer of the resistant strain showed elevated Cu2þ binding (320mg g)1 EPS) compared to that of the sensitive type (270mg g)1). The overall observations show the potential of the Cur EPS for its deployment in metal bioremediation

Isolation and Characterization of an Arsenic-Resistant Bacterium From a Bore-Well in West Bengal, India

arsenic-resistant bacterium, strain KRPC10YT, was isolated from arsenic-infested bore-well of West Bengal, India. The bacterium was resistant to exceeding concentrations of arsenate (30 mM) and arsenite (20 mM). The bacterium was Gram-positive, rod-shaped, motile and yellowish to orange-pigmented. The major fatty acids were anteiso- C15:0, iso-C15:0. The DNA G+C content was 49 mol %. Based on its phenotypic, chemotaxonomic and phylogenetic characteristics, it was identified as a member of the genus Planococcus and is the first known Planococcus resistant to arsenic. KRPC10YT was positive for indole, catalase, tolerated up to 12.0% NaCl and exhibited phenotypic differences with other type strains of genus Planococcus. Strain KRPC10YT thus could be a novel species of the genus Planococcus. The type strain is KRPC10YT (= MTCC 7758T = JCM 13947T)

Structure and properties of two component hydrogels comprising lithocholic acid and organic amines

We demonstrate the aptitude of supramolecular hydrogel formation using simple bile acid such as lithocholic acid in aqueous solution in the presence of various dimeric or oligomeric amines. By variation of the choice of the amines in such mixtures the gelation properties could be modulated. However, the replacement of lithocholic acid (LCA) by cholic acid or deoxycholic acid resulted in no hydrogel formation. FT-IR studies confirm that the carboxylate and ammonium residues of the two components are involved in the salt (ion-pair) formation. This promotes further assembly of the components reinforced by a continuous hydrogen bonded network leading to gelation. Electron microscopy shows the morphology of the internal organization of gels of two component systems which also depends significantly on the amine part. Variation of the amine component from the simple 1,2-ethanediamine (EDA) to oligomeric amines in such gels of lithocholic acid changes the morphology of the assembly from long one-dimensional nanotubes to three-dimensional complex structures. Single crystal X-ray diffraction analysis with one of the amine-LCA complexes suggested the motif of fiber formation where the amines interact with the carboxylate and hydroxyl moieties through electrostatic forces and hydrogen bonding. From small angle neutron scattering study, it becomes clear that the weak gel from LCA-EDA shows scattering oscillation due to the presence of non-interacting nanotubules while for gels of LCA with oligomeric amines the individual fibers come together to form complex three-dimensional organizations of higher length scale. The rheological properties of this class of two component system provide clear evidence that the flow behavior can be modulated varying the acid-amine ratio

Induction of glycosylation in human C-reactive protein under different pathological conditions.

As an acute-phase protein, human C-reactive protein (CRP) is clinically important. CRPs were purified from several samples in six different pathological conditions, where their levels ranged from 22 to 342 microg/ml. Small, but significant, variations in electrophoretic mobilities on native PAGE suggested differences in molecular mass, charge and/or shape. Following separation by SDS/PAGE, they showed single subunits with some differences in their molecular masses ranging between 27 and 30.5 kDa, but for a particular disease, the mobility was the same for CRPs purified from multiple individuals or pooled sera. Isoelectric focusing (IEF) also indicated that the purified CRPs differed from each other. Glycosylation was demonstrated in these purified CRPs by Digoxigenin kits, neuraminidase treatment and binding with lectins. The presence of N-linked sugar moiety was confirmed by N-glycosidase F digestion. The presence of sialic acid, glucose, galactose and mannose has been demonstrated by gas liquid chromatography, mass spectroscopic and fluorimetric analysis. Matrix-assisted laser-desorption ionization analysis of the tryptic digests of three CRPs showed systematic absence of two peptide fragments, one at the N-terminus and the other near the C-terminus. Model-building suggested that the loss of these fragments exposed two potential glycosylation sites on a cleft floor keeping the protein-protein interactions in pentraxins and calcium-dependent phosphorylcholine-binding qualitatively unaffected. Thus we have convincingly demonstrated that human CRP is glycosylated in some pathological conditions

Peridotitic minerals of the Nidar Ophiolite in the NW Himalaya: sourced from the depth of the mantle transition zone and above

<p>The Nidar Ophiolite Complex (NOC) consists of a <em>c.</em> 10 km thick ophiolite suite in the NW Himalaya, India. The <em>c.</em> 7 km thick lower ultramafic part of the ophiolite body terminates against the Tso Morari Crystallines, which represent the leading edge of the Indian continental margin. Mineral inclusions from the peridotites in the lower ultramafic part of the NOC were studied, including <em>C</em>2<em>/c</em> clinoenstatite, disordered coesite and high-pressure Mg₂SiO₄ (probably β-Mg₂SiO₄). These minerals, found in two lherzolite bodies from the ophiolite's mantle section, were characterized by laser Raman spectroscopy and electron micro-probe analysis. Textural evidence supporting decompression from an ultra-high-pressure condition was also observed, such as Cr spinel exsolution needles in olivine crystals. The systematic mineral phase transitions of coesite→quartz, high-pressure clinoenstatite→orthoenstatite and β-Mg₂SiO₄→Cr spinel exsolution needles in olivine suggest that the mantle section of the Nidar Ophiolite evolved from the deep mantle beneath a palaeo-spreading centre. The phase stabilities of these high-pressure minerals require derivation from the depth of the mantle transition zone (410–660 km). A transport mechanism for these minerals is suggested via dunite channels along a mantle adiabat in the focused convective flow below the spreading centre. This mechanism brought these deep mantle phases into the ultramafic part of the NOC. These observations suggest that some part of the mantle section of the NOC in the NW Himalaya originated in a mid-ocean ridge setting. </p

A New Sulfated Polysaccharide with Potent Blood Anti-Coagulant Activity from the Red Seaweed Grateloupia Indica

A sulfated galactan has been isolated from a red seaweed, Grateloupia indica (family: Grateloupiaceae), and has been found to possess a strong blood anti-coagulant activity