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The title compound, C(6)H(7)N(2)O(2) (+)·Br(-), is isomorphous with 2-nitro-anilinium chloride and contains an characteristic intra-molecular N-H⋯O hydrogen bond, forming an S(6) motif. Inter-molecular N-H⋯Br hydrogen bonds occur in the crystal structure. Two zigzag chains of C(2) (1)(4) motifs extend along the b-axis direction. These primary chain motifs inter-sect like a double helix structure, leading to R(6) (3)(12) ring motifs, which are arranged in tandem along the b axis. Hence, hydro-philic layers are generated at z = 1/4 and 3/4, which are sandwiched between alternate hydro-phobic layers across z = 0 and 1/2.

Pb(2+) removal ability of the immobilized and free filaments of marine cyanobacteria Oscillatoria sp. NTMS01 and Phormidium sp. NTMS02 was studied using batch experiments. Biosorption of lead by immobilized filaments was studied as a function of pH (2, 4, 6, 8, 10), contact time (5-180 min) and initial lead concentration (1, 3, 5, 7 mg/L) and the removal efficiency of free filaments was studied by culturing in the marine medium with the initial concentration (1, 3, 5, 7 mg/L) at pH 7 and incubated for 10 days. The maximum percentage removal was observed at 25 min for immobilized Oscillatoria sp. NTMS01 and 30 min for immobilized Phormidium sp. NTMS02. At 4th and 6th day of incubation, 89% and 77% removal was observed at 1 mg/L of initial lead concentration by free filaments of Oscillatoria sp. NTMS01 and Phormidium sp. NTMS02 respectively and further the removal was decreased with increasing concentration. Chlorophyll-a content was decreased in a dose dependent manner. About 40 and 50% reduction of chlorophyll-a was observed at higher concentration in Oscillatoria sp. NTMS01 and Phormidium sp. NTMS02 respectively. The adsorption capacity of immobilized Oscillatoria sp. NTMS01 was found to be (Q(max)) 217.39 which is comparatively higher than other sorbents. The Pb(2+) removal efficiency was performed as described in terms of Langmuir and Freundlich isotherms. These organisms is found to fit better by the Langmuir isotherms.

Purpose: In the frame of a research study on possible urinary markers related to physiological hormones cycle, 33 volunteer, healthy, normotensive fertile women were selected. Clinical parameters and renin-angiotensin-aldosterone system (RAAS) components were also investigated, on the basis of the well-known relation linking sex female hormones and renin and aldosterone levels., Experimental Design: A classic proteomic approach was applied to investigate urinary protein changes at different stages of menstrual cycle, specifically mid-cycle phase (G1), luteal phase (G2) and after 2 months of contraceptive therapy (G3). Analysis of urinary proteome was performed by SDS-PAGE, 2-D PAGE, Western blotting, and protein identification by HPLC-MS/MS., Results: In the four comparisons examined (G1 vs. G2; G1 vs. G3; G2 vs. G3 and G(G1+G2) vs. G3), a total of 115 protein spots were differentially represented among the subgroups. Data validation was performed by replicated experiments of immunoblotting., Conclusions and Clinical Relevance: The present work highlights for the first time variations with menstrual cycle or estroprogestin pill of newly discovered, or never related, urinary proteins. In particular, possible protein markers could be useful for further applications in contraceptive target research and RAAS modulation-related topics., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The morphological and genetic diversity of cyanobacteria associated with cycads was examined using PCR amplification techniques and 16S rRNA gene sequence analysis. Eighteen symbiotic cyanobacteria were isolated from different cycad species. One of the symbiotic isolates was a species of Calothrix, a genus not previously reported to form symbioses with Cycadaceae family, and the remainder were Nostoc spp. Axenic cyanobacterial strains were compared by DNA amplification using PCR with either short arbitrary primers or primers specific for the repetitive sequences. Based on fingerprint patterns and phenograms, it was revealed that cyanobacterial symbionts exhibit important genetic diversity among host plants, both within and between cycad populations. A phylogenetic analysis based on 16S rRNA gene sequence analysis revealed that most of the symbiotic cyanobacterial isolates fell into well-separated clades., (((c) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).)

Unlabelled: Coconut crop improvement requires a number of biotechnology and bioinformatics tools. A database containing information on CG (coconut germplasm), CCI (coconut cultivar identification), CD (coconut disease), MIFSPC (microbial information systems in plantation crops) and VO (vegetable oils) is described. The database was developed using MySQL and PostgreSQL running in Linux operating system. The database interface is developed in PHP, HTML and JAVA., Availability: http://www.bioinfcpcri.org.

Putrescine oxidase ([PO]; E.C. 1.4.3.4), which catalyzes the oxidative deamination of putrescine into gamma-aminobutyraldehyde, has been partially purified from Candida guilliermondii. Among the substrates tested, putrescine has the highest reaction rate, followed by spermidine and cadaverine. The K(m) values for putrescine, spermidine, and cadaverine were 20, 200, and 1.1 mM, respectively. The optimum pH and the temperature for PO were 8.0 and 37 degrees C, respectively. Growth of Candida species on putrescine as the sole nitrogen source induced the synthesis of PO that converts putrescine into delta 1-pyrroline and gamma-aminobutyric acid. These two products were detected and identified from the culture medium. The enzyme was not activated by divalent cations. Among the species of Candida tested, the highest enzyme activity was found in cell-free extracts of C. guilliermondii. The pathway of putrescine degradation was identified by substrate analysis to be along the nonacetylated pathway in C. guilliermondii.

The synthesis of superoxide dismutase [SOD: EC 1.15.1.1] in response to various cultural conditions was examined in Candida albicans, an opportunistic yeast which causes candidiasis in immunosuppressed patients. SOD plays an important role in protecting cells from teh oxidative damage of superoxide radicals. Maximum SOD activity was found after 72 hrs of yeast growth. The optimum pH and temperature for the SOD activity were 7 and 40 degrees C, respectively. The major SOD activity was found in the cytosol fraction and the level of extracellular SOD was very low. The enzyme was stimulated to varying degrees by cholic acid, procaine and tocopherol. On the basis of inhibitor studies and other enzyme properties, the isolated enzyme from C. albicans is identified as a copper and zinc superoxide dismutase.

Adenosine monophosphate deaminase (AMPD; EC 3.5.4.6) catalyses the hydrolysis of adenosine monophosphate (AMP) to commensurate amounts of inosine monophosphate (IMP) and ammonia. The production of AMP deaminase in Candida albicans was measured in Lee's medium grown cultures. The highest AMPD activity was observed at 24 h of growth. The enzyme had an optimum pH and temperature at 6-7 and 28 degrees C, respectively. This enzyme was inhibited under iron-limited growth conditions as well as by protease inhibitors. The AMPD of C. albicans showed a moderate increase in activity when cultures were grown in the presence of the divalent cations Mg2+, Ca2+, and Zn2+. Moreover, ADP, ATP, adenine, adenosine, deoxyribose and hypoxanthine increased the enzyme activity. Cultures grown in trypticase soy broth exhibited maximum AMPD activity compared with those grown in Sabouraud dextrose broth or Lee's medium.

The susceptibility of Aspergillus fumigatus to a series of alpha, beta-unsaturated styryl ketones known to be thiol-alkylators was examined, and the results were compared with those obtained for Candida albicans. Among 13 compounds used in our study, one (designated NC1110) inhibited the growth of A. fumigatus completely at low concentrations (minimum inhibitory concentration = 32 microM). Structure-activity analysis of these compounds indicated that the electron attracting property as well as the overall hydrophobicity of the compounds are important parameters for their antifungal activity. These preliminary results suggest that further modification of these molecules to enhance their hydrophobicity and the electron attracting property may result in more active compounds with improved antifungal activity.

Candida albicans is a dimorphic yeast capable of producing alternate morphological forms (yeast or mycelium) in response to environmental changes. The intracellular level of glutathione, which helps to maintain the redox potential of the cell, is decreased significantly during the thermal induction of yeast-to-mycelium conversion. The reason for the decline of glutathione in the mycelial form is not understood. We have, therefore, investigated the levels of glutathione reductase, glutathione S-transferase, gamma-glutamyltranspeptidase, and glutathione peroxidase, four key enzymes involved in glutathione metabolism, in the yeast and mycelial forms. Yeast cells of C. albicans 3153A were induced in Lee's medium (pH 6.5) at 37 degrees C for 3 h to produce germ tubes. Cell lysates were prepared from yeast and mycelial cells, and glutathione reductase, glutathione S-transferase, gamma-glutamyltranspeptidase, and glutathione peroxidase were assayed spectrophotometrically. There was a 640% increase of the level of gamma-glutamyltranspeptidase in the germ tubes as compared with the yeast cells. No other significant alteration of the levels of enzymes was noted. This increased activity of gamma-glutamyltranspeptidase, which cleaves the glutamic acid residue of glutathione (Glu-Cys-Gly) appears to be, at least in part, responsible for the rapid decrease of the intracellular glutathione in C. albicans during the yeast-to-mycelium conversion.

Candida albicans is a dimorphic pathogenic yeast capable of producing alternate morphological forms (yeast or mycelium) in response to environmental changes. The dimorphism of C. albicans plays an important role in the pathophysiology of this organism. The intracellular level of glutathione, which helps to maintain the oxidation-reduction potential of the cell, is decreased significantly during the yeast-to-mycelium conversion implicating the possible involvement of thiols in the yeast-to-mycelium transition. To evaluate the possible participation of sulphydryl group(s) containing component(s) in the yeast-to-mycelium transition of C. albicans, we examined the effect of a group of newly synthesized thiol-alkylators on the production of germ tubes from yeast cells. Several conjugated styryl ketones which are thiol-alkylators, and p-chloromercuriphenylsulphonate (a known nonpenetrating thiol-blocker) inhibited the yeast-to-mycelium conversion of C. albicans. The thiol-alkylators at 20 microM failed to inhibit four key enzymes (gamma-glutamyltranspeptidase, glutathione reductase, glutathione S-transferase and glutathione peroxidase) involved in glutathione utilization indicating that the inhibition of yeast-to-mycelium conversion is not mediated by the inhibition of glutathione metabolic enzymes. Moreover, these results suggest that a key thiol-blocker sensitive component(s) containing a critical sulphydryl group(s) is involved in the yeast-to-mycelium transition of C. albicans.

Glutamine synthetase (GS, EC 6.3.1.2) from Nocardia asteroides was purified to homogeneity by ammonium sulfate precipitation, Sephadex G-150, and DEAE-Sepharose chromatography. The native molecular weight of the purified enzyme was determined to be 720 kDa. SDS-PAGE analysis of the purified preparation revealed a single band corresponding to 59 kDa, indicating the possible presence of 12 identical subunits. The divalent cations Mn2+ and Mg2+ were found to be essential for optimal transferase and biosynthetic activity, respectively. The optimal pH and temperature for both activities of the enzyme were found to be 7.2 and 50 degrees C. Amino acids such as L-alanine, glycine, and aspartate inhibited the GS activity. The Km values for the substrates of the biosynthetic reaction ATP, glutamate, and ammonium chloride were found to be 400 microM, 7.7 mM, and 200 microM, respectively. Addition of ammonium chloride to the nitrogen-limited culture resulted in a decrease of GS transferase and biosynthetic activities. Phosphodiesterase treatment of the extract from ammonia-shocked cultures showed an increase in GS transferase activity. The results indicate the possible regulation of GS by covalent modification.

The effect of carbon sources, glucose and sucrose, and nitrogen sources such as ammonia, glutamate and L-citrulline on the activities of glutathione metabolic enzymes has been studied. Yeast and mycelial cells were used to identify changes in activity levels of glutathione reductase (GSSGR), glutathione transferase (GST), glutathione peroxidase (GPX) and gamma-glutamyl transpeptidase (GGT). Enzyme activities from cells grown in sucrose media were lower than in glucose media regardless of the enzyme tested, morphological form, or the growth interval. In all enzymes except GST, activity was higher in yeast form than in mycelia, regardless of nitrogen source, with lower activity from 24 to 72 h than at 96 h. In citrulline media, yeast form showed the maximum GST, GGT, and GPX activity. In ammonia-amended media, mycelia showed maximum activity in GGT, whereas in glutamate media, mycelia showed the maximum activity in GST. Also, the type of nitrogen source had no effect on GPX activity in the mycelial form. Finally, changing the nitrogen source showed no significant effect on GSSGR activity, either in the yeast or mycelial form.

Mycelia of Phymatotrichum omnivorum obtained at 10 day intervals during 10 to 50 days of growth were used for isolating calmodulin, and studying its effect on glycogen synthase, phosphorylase, phosphorylase kinase, cyclic AMP phosphodiesterase and Ca++ATPase. Glycogen synthase was inhibited until the 30th day by calmodulin, whereas calmodulin obtained from the 40th day stimulated glycogen synthase activity and the 50th day sample had no effect. cAMP phosphodiesterase and Ca++ATPase of P. omnivorum were stimulated by the respective calmodulin. Molecular weight of the purified fungal calmodulin was approximately 18 kD as revealed by sodium dodecyl sulphate gel electrophoresis. Trifluoperazine, dibucaine and lidocaine inhibited calmodulin activity and calmodulin activation of PDE, respectively.

The growth and production of hydrolytic enzymes such as alpha-amylase, esterase and peroxidase as influenced by the type of media, carbon and nitrogen sources and C:N ratio were monitored in Nocardia asteroides at 37 degrees C. Sabouraud dextrose and the synthetic media yielded maximum growth compared with tryptic soy broth. Among the carbon sources (dextrose, fructose, sucrose, maltose, starch and citrate), monosaccharides supported maximum growth and induced higher alpha-amylase activity but repressed the peroxidase activity. On the other hand, the disaccharides and starch produced less growth but induced maximum esterase and peroxidase activities. Glutamate among the nitrogen sources (nitrate, nitrite, ammonium, hydroxylamine, glutamate and casein) supported maximum growth. Glutamate, nitrate and casein induced alpha-amylase and esterase activities but suppressed peroxidase activity. Nitrite, ammonium and hydroxylamine stimulated peroxidase activity to the maximum but repressed alpha-amylase and esterase activities. Low, medium and high C:N ratios induced maximum peroxidase, esterase and alpha-amylase activities, respectively.

The lactate dehydrogenase (LDH) from Nocardia asteroides was purified to homogeneity by ammonium sulphate precipitation, gel filtration on Sephadex G-150 and DEAE-Sepharose column chromatography. The purified enzyme showed a single band in native condition which indicated its homogeneity. SDS-PAGE of the purified enzyme showed the presence of three bands which correspond to molecular weights of 60, 66 and 74 kDa. The pH and temperature optima of the purified enzyme were 9.5 and 50 degrees C, respectively. The metal ions Mn++, Fe++, Co++, Mg++ and Ca++, increased the purified LDH activity. On the other hand, enzyme activity was completely inhibited by CuCl2. Potassium chloride, ammonium sulphate and sodium chloride did not alter the enzyme activity. The purified enzyme exhibited a Km value of 1.6 x 10(-5) M for pyruvate.

The cotton root rot fungus, Phymatotrichum omnivorum, synthesized indole acetic acid (IAA) in culture medium containing tryptophan as the only source of nitrogen. Synthesis of IAA was not affected by illumination, and maximum amounts of the auxin were produced at 30 days. The optimum hydrogen ion concentration and temperature for IAA production were 6.5 and 28 degrees C, respectively. Indole ethanol (IEA) was also detected in tryptophan media, primarily during the active growth of the organism.

The production of extracellular amylase by P. omnivorum has been studied under different cultural conditions. Maximum mycelial growth and amylase synthesis were found in basal synthetic medium containing 2% glycogen as the carbon source. Significant amounts of amylase and growth were obtained in medium containing other carbon compounds with alpha-1, 4-linkages. Optimum temperatures for mycelial growth and amylase synthesis were found at 28 degree and 30 degree C, respectively. Of all the nitrogenous compounds tested, ammonium nitrate supported the maximum mycelial growth and amylase production. Increasing the concentration of starch in the basal medium increased the growth as well as the enzyme synthesis.