Microbial community diversity of an integrated constructed wetland used for treatment of sewage

The microbial community diversity in Constructed Wetland System (CWS) plays a key role in the removal of pollutants from waste water. An integrated functional CWS developed at Neela Hauz Biodiversity Park, Delhi was selected to assess the diversity in composition and structure of microbial community diversity of sludge and sediment of CWS, based on metagenomic approach using 16S rRNA genes. The sediment showed higher diversity than sludge and both formed distinct clusters. The taxonomic structure of the microbial community of CWS is represented by 6,731 OTUs distributed among 2 kingdoms, 103 phyla, 227 classes, 337 orders, 320 families, 295 identified genera, and 84 identified species. The relative abundance of top 5 dominant phyla of sludge and sediment varied from 3.77% (Acidobacteria) to 35.33% (Proteobacteria) and 4.07% (Firmicutes) to 28.20% (Proteobacteria), respectively. The range of variation in relative abundance of top 5 dominant genera of sludge and sediment was 2.58% (Hyphomicrobium) to 6.61% (Planctomyces) and 2.47% (Clostridium) to 4.22% (Syntrophobacter), respectively. The rich microbial diversity of CWS makes it perform better in pollutants removal (59.91-95.76%) than other CWs. Based on the abundance values of taxa, the taxa are grouped under four frequency distribution classes-abundant (>20), common (10-19), rare (5-9), and very rare (1-4). The unique structure of microbial communities of integrated CWS is that the number of abundant taxa decreases in descending order of taxonomic hierarchy, while the number of rare and very rare taxa increases. For example, the number of abundant phyla was 14 and 21 in sludge and sediment, respectively and both communities have only 3 abundant genera each. This is in contrast to 4 and 17 very rare phyla in sludge and sediment, respectively and both the communities have 114 and 91 very rare genera, respectively. The outcomes of the study is that the integrated CWS has much higher microbial community diversity than the diversity reported for other CWs, and the rich diversity can be used for optimizing the performance efficiency of CWS in the removal of pollutants from waste water. Such structural diversity might be an adaptation to heterogeneous environment of CWS.

Arbuscular mycorrhizas accelerate the degradation of colour containing organic pollutants present in distillery spent wash leachates

Distillery spent wash (DSW) from molasses-based distilleries is being used as a low-cost alternative to chemical fertilizers in countries like India and Brazil. However, using DSW as a fertilizer substitute causes organic pollutant leaching, including melanoidins and caramel colourants that turn bodies of water dark brown. This study investigated the arbuscular mycorrhiza (AM) mediated degradation of organic pollutants in DSW. Mycorrhizal and non-mycorrhizal Sorghum bicolor were grown in microcosms for 16 weeks. The plants were fertilized with either raw DSW or Hoagland solution. Leachates draining from the microcosms after fertilization were collected three times in 30-day intervals. Each 30-day collection was preceded by two fertilizations. A gas chromatography-mass spectrometry comparative analyses of raw DSW with leachates of the third collection from mycorrhizal and non-mycorrhizal microcosms was made. Sixty-five and 42 complex organic compounds were detected in raw DSW and leachate collected from the non-mycorrhizal pots respectively. Only 26 compounds were detected in leachate collected from mycorrhizal pots. Absent from leachate of the mycorrhizal pots were: colour-containing organic compounds diacetone alcohol; 3-amino-2-cyano-6-methyl-6,7-dihydrothieno[2,3-b]pyrazine S-oxide; cyclohexane; 1,2-benzenedicarboxylic acid, butyl 8-methylnonyl ester; 2-pyrrolidinone; and acetic acid, dodecyl ester present in raw DSW. The results indicate that AM fungi can degrade organic pollutants in DSW.

Assessment of oxidative stress markers and concentrations of selected elements in the leaves of Cassia occidentalis growing wild on a coal fly ash basin

Assessment of oxidative stress levels and tissue concentrations of elements in plants growing wild on fly ash basins is critical for realistic hazard identification of fly ash disposal areas. Hitherto, levels of oxidative stress markers in plants growing wild on fly ash basins have not been adequately investigated. We report here concentrations of selected metal and metalloid elements and levels of oxidative stress markers in leaves of Cassia occidentalis growing wild on a fly ash basin (Badarpur Thermal Power Station site) and a reference site (Garhi Mandu Van site). Plants growing on the fly ash basin had significantly high foliar concentration of As, Ni, Pb and Se and low foliar concentration of Mn and Fe compared to the plants growing on the reference site. The plants inhabiting the fly ash basin showed signs of oxidative stress and had elevated levels of lipid peroxidation, electrolyte leakage from cells and low levels of chlorophyll a and total carotenoids compared to plants growing at the reference site. The levels of both protein thiols and nonprotein thiols were elevated in plants growing on the fly ash basin compared to plants growing on the reference site. However, no differences were observed in the levels of cysteine, reduced glutathione and oxidized glutathione in plants growing at both the sites. Our study suggests that: (1) fly ash triggers oxidative stress responses in plants growing wild on fly ash basin, and (2) elevated levels of protein thiols and nonprotein thiols may have a role in protecting the plants from environmental stress.

Purification, characterization and immunolocalization of a novel protease inhibitor from hemolymph of tasar silkworm, Antheraea mylitta

A novel serine protease inhibitor (AmPI) was purified from larval hemolymph of tasar silkworm, Antheraea mylitta by two-step process of trypsin-affinity and gel-filtration (FPLC) chromatography. AmPI was active against larval midgut and commercial bovine trypsin and chymotrypsin. The extent of purification was determined by SDS and Native PAGE. The protease inhibitor had an apparent molecular weight of approximately 14.5 kDa as determined by SDS-PAGE. Its activity was stable over a pH range of 4.5-9 and temperatures range of 4-65 degrees C. Molecular weight as determined by MALDITOF-MS was between 13241.63 and 13261.66 Da. MS profile of AmPI also suggests two isoforms of AmPI because of glycosylation by heptose (C(7)H(14)O(7)). This confirmed the result of Native PAGE showing two bands. N-terminal amino acid sequence of this protein did not show similarity to any known protease inhibitor. To study the functional implications of AmPI in insect, it was localized in insect body tissue of different larval instars by immunogold labeling technique using GAR-gold conjugate as secondary antibody. The pattern of localization suggests constitutive nature of AmPI, which may have role in insect's defense mechanism.

Comparative study on elemental composition and DNA damage in leaves of a weedy plant species, Cassia occidentalis, growing wild on weathered fly ash and soil

Open dumping of fly ash in fly ash basins has significant adverse environmental impacts due to its elevated trace element content. In situ biomonitoring of genotoxicity is of practical value in realistic hazard identification of fly ash. Genotoxicity of openly disposed fly ash to natural plant populations inhabiting fly ash basins has not been investigated. DNA damage, and concentrations of As, Co, Cr, Cu and Ni in the leaves of natural populations of Cassia occidentalis growing at two contrasting sites-one having weathered fly ash (fly ash basin) and the other having soil (reference site) as plant growth substrates-were assessed. The foliar concentrations of As, Ni and Cr were two to eight fold higher in plants growing on fly ash as compared to the plants growing on soil, whereas foliar concentrations of Cu and Co were similar. We report, for the first time, based upon comet assay results, higher levels of DNA damage in leaf tissues of Cassia occidentalis growing wild on fly ash basin compared to C. occidentalis growing on soil. Correlation analysis between foliar DNA damage and foliar concentrations of trace elements suggests that DNA damage may perhaps be associated with foliar concentrations of As and Ni. Our observations suggest that (1) fly ash triggers genotoxic responses in plants growing naturally on fly ash basins; and (2) plant comet assay is useful for in situ biomonitoring of genotoxicity of fly ash.

Bioinsecticidal activity of Archidendron ellipticum trypsin inhibitor on growth and serine digestive enzymes during larval development of Spodoptera litura

The roles of serine proteases involved in the digestion mechanism of the cutworm Spodoptera litura (Lepidoptera: Noctuidae) were examined (in vitro and in vivo) following feeding of plant protease inhibitors. A trypsin inhibitor from Archidendron ellipticum (AeTI) was purified by ammonium sulfate fractionation, ion-exchange chromatography and size-exclusion chromatography (HPLC) and its bioinsecticidal properties against S. litura were compared with Soybean Kunitz trypsin inhibitor (SBTI). AeTI inhibited the trypsin-like activities of the midgut proteases of fifth instar larvae of S. litura by over 70%. Dixon plot analysis revealed competitive inhibition of larval midgut trypsin and chymotrypsin by AeTI, with an inhibition constant (K(i)) of 3.5x10(-9) M and 1.5x10(-9) M, respectively. However, inhibitor kinetics using double reciprocal plots for both trypsin and chymotrypsin inhibitions demonstrated a mixed inhibition pattern. Feeding experiments conducted on different (neonate to ultimate) instars suggested a dose-dependent decrease for both the larval body weight as well as % survival of larva fed on diet containing 50, 100 and 150 microM AeTI. Influence of AeTI on the larval gut physiology indicated a 7-fold decrease of trypsin-like protease activity and a 5-fold increase of chymotrypsin-like protease activity, after being fed with a diet supplemented with 150 microM AeTI. This study suggests that although the early (1st to 3rd) larval instars of S. litura are susceptible to the trypsin inhibitory action of AeTI, the later instars may facilitate the development of new serine proteases, insensitive to the inhibitor.

A trypsin and chymotrypsin inhibitor from Caesalpinia bonduc seeds: isolation, partial characterization and insecticidal properties

Evolution of proteinase inhibitor diversity in leguminous plants of tropical rainforests is under immense pressure from the regular upregulation of proteolytic machinery of their pests. The present study illustrates the isolation and bioinsecticidal potency of a serine proteinase inhibitor from the seeds of Caesalpinia bonduc (CbTI), inhabiting Great Nicobar Island, India. Following initial fractionation by ammonium sulfate precipitation, CbTI was purified to homogeneity by ion exchange, gel filtration and trypsin affinity chromatography. SDS-PAGE of gel filtrated CbTI showed a couple of proteins CbTI-1 ( approximately 16kDa) and CbTI-2 (20kDa) under non-reducing conditions, which subsequent to trypsin affinity chromatography yielded only CbTI-2. Both Native PAGE as well as iso-electric focusing showed 2 iso-inhibitors of CbTI-2 (pI values of 5.35 and 4.6). CbTI exhibited tolerance to extremes of temperatures (0-60 degrees C) and pH (1-12). A 1:1 stoichiometric ratio was noted during CbTI-2-trypsin complex formation, which was absent on binding with chymotrypsin. Further, SDS-PAGE analysis also showed that CbTI-1 has affinity only towards chymotrypsin, whereas both trypsin and chymotrypsin formed complexes with CbTI-2. Dixon plot analysis of CbTI-2 yielded inhibition constants (K(i)) of 2.75 x 10(-10)M and 0.95 x 10(-10)M against trypsin and chymotrypsin activity respectively. Preliminary investigations on the toxicological nature of CbTI revealed it to be a promising bioinsecticidal candidate.

Exploring the protease mediated conformational stability in a trypsin inhibitor from Archidendron ellipticum seeds

A Kunitz proteinase inhibitor from Archidendron ellipticum seeds (AeTI) was purified and complexed with bovine trypsin and chymotrypsin. The stoichiometric stability of AeTI with its interacting proteinases was then investigated using spectrophotometric, size exclusion chromatography (HPLC system), Western blotting and circular dichroism (CD) studies. All the methods were remarkably similar in revealing the preference of trypsin over chymotrypsin by AeTI for complex formation. Both Western blotting as well as spectrophotometry based assays for competition experiments indicated that trypsin displaces chymotrypsin from a previously formed AeTI-chymotrypsin complex. Chemical modification of lysine and arginine by TNBS and CHD treatments, respectively, suggested a lysine as the active site residue and also indicated the presence of a single protease-binding site for AeTI. CD of native AeTI showed a sharp minimum at 200 nm and deconvolution of the CD spectra revealed it to be an unordered protein possessing high beta-sheet content. Complex formation of AeTI with trypsin induces a fractional switchover of its unordered structure towards the beta-sheet fraction but lacked any such conversion in the presence of chymotrypsin. Prolonged exposure of excess trypsin generates conformational modifications both in the secondary and the tertiary structures.

Novel mode of resistance to Fusarium infection by a mild dose pre-exposure of cadmium in wheat

Exposure of healthy wheat seeds (Triticum aestivum var Sonalika) to mild dose of cadmium (Cd(2+)) given as 50 microM CdCl(2) for 48 h and then washed off Cd(2+) offered resistance to the subsequent infection by Fusarium oxysporum inoculum. Seven days old seedlings having two primary leaves were aseptically inoculated with fungus, F. oxysporum (1 x 10(6)) spores. The seedlings pre-exposed to low level of Cd(2+) survived the Fusarium infection, while plantlets without Cd(2+) stress wilted and then perished due to Fusarium infection. The stress associated proteins induced by Cd(2+) (50 microM), F. oxysporum and by the co-stress (50 microM Cd(2+) and then with F. oxysporum) treatments were observed to be of same molecular weight (51 kDa). Antibody was raised against the purified Cd(2+)-stress associated protein (CSAP). Immuno-gold labeling of wheat seedling root tissue showed the presence of this CSAP in Cd(2+) pre-exposed and in co-stressed tissues and to be located predominantly on the inner linings of the cell membranes. We also observed that the anti-CSAP-antibody also labeled the root tissue of only Fusarium inoculated seedlings and the gold labeling was intensely located on the membrane. This cross-reaction of anti-CSAP suggests that Fusarium-induced stress protein (FISP) possibly has close homology to CSAP. We thus show for the first time the over expression of a high molecular mass protein by mild dose of Cd(2+) pre-exposure to wheat seeds which subsequently provided protection against Fusarium infection. This mode of resistance developed by an abiotic stress-causing agent against pathogen infection is novel.

Induction of biomolecules in mature leaves of Terminalia arjuna due to feeding of Antheraea mylitta Drury

Terminalia arjuna is an important food plant of the tasar silkworm, Antheraea mylitta Drury. In this study, we investigated the induction of biomolecules in mature leaves of these plants subjected to insect feeding. Increase in total tannin content, lipid peroxidation, and trypsin inhibitor activity have been observed in mature leaves damaged by the insects. The growth rate of Vth instar larvae of A. mylitta fed on previously damaged foliage reduced by 87.1%. Induction of biomolecules for defense mechanisms in relation to herbivore damage has been discussed.

Cold stress induced high molecular weight membrane polypeptides are responsible for cold tolerance in Rhizobium DDSS69

Cold stress induces a lag phase in the growth cycle of Rhizobium DDSS69. Two cold sensitive mutants of DDSS69 were generated through Tn5 tagged mutagenesis. These mutants do not grow below 15 degrees C but show a growth curve comparable with the wild type grown at 5 degrees C. There is a rapid induction of two high molecular weight membrane polypeptides of 135 and 119 kDa within 15 min of exposure to 5 degrees C in DDSS69. PAGE membrane protein profiles of stressed and non-stressed cells reveal differential regulation of genes. At 15 degrees C both mutants lack the high molecular weight polypeptides, suggesting a role in alleviation of cold stress.

Detection of root mucilage using an anti-fucose antibody

Plant root mucilage is known to enhance soil quality by contributing towards the soil carbon pool, soil aggregation, detoxification of heavy metal ions and interactions with rhizospheric microflora. Mucilage consists of many monosaccharide units, including fucose which can be used as an indicator for plant root based polysaccharides. This is the first report of an immunological technique developed to use anti-fucose antibodies as markers for probing and localizing fucosyl residues in mucilage polysaccharide and, in turn, for localization of plant root mucilage. Fucose was complexed with bovine serum albumin to raise antibodies against fucose. A fucose-directed antibody was shown to cross-react with root cap mucilages from grasses. This antibody was used to localize root mucilage polysaccharide in maize and wheat root caps using immunogold electron microscopy. Abundant labelling could be localized on the cell wall, and in the intercellular matrix and vesicles of the peripheral root cap cells. Labelling was less intense in cells towards the centre of the root cap tissue. Control experiments confirmed that immunogold localization of fucose was specific and reliable.

Molecular diversity of the plasmid genotypes among Rhizobium gene pools of sesbanias from different habitats of a semi-arid region (Delhi)

Plasmid genotypes of root nodulating rhizobial isolates of Sesbania, sampled from six ecologically distinct habitats, were characterized. Plasmid profile analysis revealed nine different plasmid types having molecular masses ranging from 30 to 300 MDa, distributed among six profile types that grouped the isolates into six plasmid classes. The six plasmid profiles were diverged from each other and lack many common plasmid types among them. Variation in number and types of symbiotic (Sym) plasmid was assessed by hybridization of plasmid profiles with sym gene probes. Relatedness among different plasmid types was assessed by hybridization of total DNAs as well as plasmid profiles of different isolates with labelled intact plasmid. Plasticity of plasmid genotype and possible recombination between different plasmid types is suggested from the results obtained. Structural diversity among sym plasmids was assessed by PCR amplified product profiles using primer corresponding to the reiterated nif promoter consensus element (NPC-PCR). A total of 26 NPC-PCR profile types were recognized. Genetic diversity among sym plasmids of isolates belonging to the same plasmid class and having similar sym plasmid suggested recombinations and rearrangements of sequences within the sym plasmids. Cluster analysis based upon similarity among profile types sorted the isolates across the ecological gradient. We suggest that habitat heterogeneity and plasticity of plasmid genotype together contribute for the generation of genetic diversity leading to strainal differentiation in rhizobia.

Oligomerization of the integrin alphaIIbbeta3: roles of the transmembrane and cytoplasmic domains

Integrins are a family of alpha/beta heterodimeric membrane proteins, which mediate cell-cell and cell-matrix interactions. The molecular mechanisms by which integrins are activated and cluster are currently poorly understood. One hypothesis posits that the cytoplasmic tails of the alpha and beta subunits interact strongly with one another in a 1:1 interaction, and that this interaction is modulated in the course of the activation of alphaIIbbeta3 [Hughes, P. E., et al. (1996) J. Biol. Chem. 271, 6571-6574]. To examine the structural basis for this interaction, protein fragments encompassing the transmembrane helix plus cytoplasmic tails of the alpha and beta subunits of alphaIIbbeta3 were expressed and studied in phospholipid micelles at physiological salt concentrations. Analyses of these fragments by analytical ultracentrifugation, NMR, circular dichroism, and electrophoresis indicated that they had very little or no tendency to interact with one another. Instead, they formed homomeric interactions, with the alpha- and beta-fragments forming dimers and trimers, respectively. Thus, these regions of the protein structure may contribute to the clustering of integrins that accompanies cellular adhesion.

Inhibition of the in-vitro growth of Mycobacterium tuberculosis by a phytosiderophore

Non-compliance by patients and poor clinical management due to the use of incorrect regimens are the main reasons for the development of drug resistance by mycobacterial strains. New strategies for the control of multi-drug-resistant mycobacterial strains have become a necessity for proper management of tuberculosis, which, according to the WHO report (1997), is estimated to remain among the top 10 mortality-causing diseases of the twenty-first century. One of the strategies is the use of iron-sequestering agents like siderophores as active therapeutic agents in the treatment of tuberculosis. This report describes for the first time the inhibition of the growth of Mycobacterium tuberculosis H37Ra in vitro by a phytosiderophore isolated from the root washings of Tephrosia purpurea. This finding may help in the establishment of a new drug regimen which will be more effective in the treatment of tuberculosis.

Poly-beta-hydroxybutyrate metabolism is affected by changes in respiratory enzymatic activities due to cold stress in two psychrotrophic strains of Rhizobium

Cold stress resulted in a decrease in the poly-beta-hydroxybutyrate (PHB) content of non-cold-acclimated Rhizobium DDSS69 cultures. Analysis of the specific activity of beta-ketothiolase and beta-hydroxybutyrate dehydrogenase revealed that decrease in PHB levels was a result of the inhibition of synthesis of PHB rather than an increase in its breakdown. Rhizobium ATR1, a cold-acclimated strain, revealed the presence of a stable PHB metabolism that did not show any significant differences either in PHB levels or in the activity of enzymes of the PHB metabolism under cold stress, suggesting that PHB is not involved in cold tolerance. Analysis of specific activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase of the pentose phosphate pathway showed the upward regulation of alternate pathways of carbohydrate metabolism under cold stress to rapidly generate energy to overcome the stress. There is diversity in the switching mechanisms of carbon metabolism among cold-acclimated and non-cold-acclimated Rhizobium isolates. Upward regulation of malate dehydrogenase in both isolates suggests that it is a critical input for cold tolerance.

Study of the problem of hidden cases of leprosy among "inaccessible" section of urban population in Madras City

A questionnaire survey was conducted amongst 1300 general practitioners (GPs) of Madras city to assess the magnitude of leprosy problem amongst the upper middle class and upper class populations who are getting treatment from these GPs. A total of 2944 leprosy patients were being treated by 200 GPs. One third of these patients belonged to the upper middle/upper class section of the population living in the city of Madras.

Cold stress induces switchover of respiratory pathway to lactate glycolysis in psychrotrophic Rhizobium strains

Two psychrotrophic strains of Rhizobium, DDSS69, a non-cold acclimated strain, and ATR1, a cold acclimated strain, were subjected to cold stress. A 4-fold increase in the specific activity of lactate dehydrogenase (LDH) was characteristic for cold stressed cells of DDSS69, whereas ATR1 showed a higher LDH activity in general, which increased 1.5-fold under cold stress. Cold sensitive mutants of DDSS69 which could not grow below 15 degrees C, in contrast to the wild type which could grow at 5 degrees C, were isolated using Tn5-tagged mutagenesis. These mutants showed a 40% lower LDH activity than the wild type grown at 5 degrees C that was comparable to the wild type grown at 15 degrees C. High specific activity of succinic dehydrogenase (SDH) at 28 degrees C in both strains and mutants indicated that aerobic respiration via the citrate cycle is the normal mode of saccharide utilization. Shifts to lower temperatures decreased the specific activity of SDH. However, alcohol dehydrogenase (ADH) activity remained very low in both the strains and the mutants at low temperatures indicating that a shift from aerobic saccharide metabolism to anaerobic one under cold stress involves lactate glycolysis rather than alcohol fermentation. There was an increase in membrane-bound ATPase activity under cold stress which is correlated to higher LDH activity. These data show that, in psychrotrophic Rhizobium strains, cold stress induces a switchover of respiratory metabolism from aerobic to anaerobic pathway, especially lactate glycolysis.

Identification of novel serine proteinase gene transcripts in the midguts of two tropical insect pests, Scirpophaga incertulas (Wk.) and Helicoverpa armigera (Hb.)

We have used RT PCR and 3'RACE to identify diverse serine proteinase genes expressed in the midguts of the rice yellow stem borer (Scirpophaga incertulas) and Asian corn borer (Helicoverpa armigera). The RT-PCR primers encoded the conserved regions around the active site histidine57 and serine195 of Drosophila melanogaster alpha trypsin, including aspartate189 of the specificity pocket. These primers amplified three transcripts (SiP1-3) from midguts of S. incertulas, and two transcripts (HaP1-2) from midguts of H. armigera. The five RT PCR products were sequenced to permit design of gene-specific forward primers for use with anchored oligo dT primers in 3'RACE. Sequencing of the 3'RACE products indicated that SiP1, SiP2 and HaP1 encoded trypsin-like serine proteinases, while HaP2 encoded a chymotrypsin-like serine proteinases. The SiP3 transcript proved to be an abundant 960 nt mRNA encoding a trypsin-like protein in which the active site serine195 was replaced by aspartate. The possible functions of this unusual protein are discussed.

NMR solution structure of plastocyanin from the photosynthetic prokaryote, Prochlorothrix hollandica

The solution structure of a divergent plastocyanin (PC) from the photosynthetic prokaryote Prochlorothrix hollandica was determined by homonuclear 1H NMR spectroscopy. Nineteen structures were calculated from 1222 distance restraints, yielding a family of structures having an average rmsd of 0.42 +/- 0.08 A for backbone atoms and 0.71 +/- 0.07 A for heavy atoms to the mean structure. No distance constraint was violated by more than 0.26 A in the structure family. Despite the low number of conserved residues shared with other PC homologues, the overall folding pattern of P. hollandica PC is similar to other PCs, in that the protein forms a two-sheet beta-barrel tertiary structure. The greatest variability among the backbone structures is seen in the loop region from residues 47-60. The differences seen in the P. hollandica PC homologue likely arise due to a small deletion of 2-4 residues compared to the PC consensus; this yields a less extended loop containing a short alpha-helix from residues Ala52-Leu55. Additionally, the protein has an altered hydrophobic patch thought to be important in binding reaction partners. Whereas the backbone structure is very similar within the loops of the hydrophobic region, the presence of two unique residues (Tyr12 and Pro14) yields a structurally different hydrophobic surface likely important in binding P. hollandica Photosystem I.

Exposure to pulsed magnetic fields in the treatment of plantar ulcers in leprosy patients--a pilot, randomized, double-blind, controlled clinical trial

A pilot, randomized, double-blind, controlled clinical trial to study the effect of exposure to pulsed magnetic fields (PMF) on the rate of healing of plantar ulcers in leprosy patients was undertaken. Twenty patients were randomly allocated to receive standard wound-care treatment (controls) and 20 others received standard treatment plus exposure to PMF (sinusoidal form, 0.95 to 1.05 Hz, amplitude +/- 2400 nano Teslas) (study group) for four weeks. Assessment of the outcome of treatment was based on the volume of ulcers, calculated from the maximal length, breadth and depth of the ulcer recorded on the day of admission, at one and two weeks and at the end of treatment. The analysis of the results was based on 15 control patients and 18 PMF patients after deletion of four patients due to irregularity in attendance and three others on account of suspected malignancy of the ulcers. In the control group, the geometric mean volumes of the ulcers were 2843 and 1478 cu mm on the day of admission and at the end of the treatment (P = 0.03); the corresponding values in the PMF group were 2428 and 337 cu mm, respectively (P < 0.001). A decrease in the volume of 40% or more was observed in 53% of control patients and 89% of PMF patients (P = 0.02); a decrease of 80% or more was observed in none of the controls and in 33% of PMF patients. These findings strongly suggest that exposure to PMF causes a significantly more rapid healing of plantar ulcers in leprosy patients.

Reconstitution and characterization of a divergent plastocyanin from the photosynthetic prokaryote, Prochlorothrix hollandica, expressed in Escherichia coli

Plastocyanin (PC) is a copper protein that serves as a mobile electron carrier between cytochrome f and Photosystem I in the light reactions of photosynthesis. Despite large variability in amino acid sequences and isoelectric points, PCs from cyanobacterial and chloroplast sources reveal considerable similarities with respect to their secondary and tertiary structures. In this paper, we have expressed in Escherichia coli a PC from the prokaryote Prochlorothrix hollandica, and efficiently reconstituted the protein with copper under conditions yielding the characteristics of a native holoPC, as judged by redox titration (Eo' = +376 mV), near and far UV circular dichroism, and electron paramagnetic resonance (EPR) spectroscopy. By comparison of amino acid sequences, P. hollandica PC is the most divergent homolog identified to date, and analysis of this reconstituted preparation may reveal new insights as to the structural requirements for electron transport between the PC copper center and neighboring reaction partners.

Localization of peanut (Arachis hypogaea) root lectin (PRA II) on root surface and its biological significance

The glucose-specific peanut root lectin, PRA II, is localized on the surface of 7-day-old peanut seedling root and in root cortical parenchymatous cells. The lectin is eluted from intact roots upon washing with buffer containing glucose. Rabbit erythrocytes bind to the root surface and the cortical cells; the binding is inhibited by antibodies raised against PRA II, peanut-specific Rhizobium cells and by glucose. Lipopolysaccharides isolated from host-specific Rhizobium strain inhibit the haemagglutinating activity of PRA II and are precipitated by the lectin. Our results suggest that PRA II might be involved in recognition of Rhizobium by peanut roots.

Further characterization of glucose-specific peanut root lectin (PRA II)

Amino acid analysis of PRA II, a glucose-specific lectin isolated from 7 day-old peanut seedling roots shows that this lectin is rich in glycyl (103 per mole) and seryl residues (59 per mole), and poor in essential amino acids, the acidic amino acid content is higher than the basic amino acids and that its amino acid composition differs from its seed counterpart (PNA), although neither of the lectins contains cystein. PRA II has two carbohydrate binding sites per molecule as determined by equilibrium dialysis. Modifications of the specific amino acid residues of the lectin with group specific reagents indicate that hydroxyl group of tyrosine is involved in the binding of carbohydrate to PRA II.

Isolation and characterization of a lectin from peanut roots

A glucose-specific lectin has been purified to apparent homogeneity from 7-day-old peanut (Arachis hypogaea) roots by affinity chromatography on a Sephadex G-50. The lectin has a 66 kDa native molecular mass and a 33 kDa subunit molecular mass as revealed by native and denaturing sodium dodecyl sulphate-polyacrylamide gel electrophoresis, respectively. The purified lectin, gives a single precipitin line with the antiserum produced against 7-day-old root extract and shows 5 bands in the pH range of 4.4-5.4 in the isoelectric focusing gel. The glucose-specific lectin activity in the peanut roots appears from the fourth day onwards. Lipopolysaccharides isolated from the host specific Rhizobium strain are a 68-fold more potent inhibitor of the lectin as compared to glucose.

Moyamoya disease: computed tomographic and angiographic correlation in 10 caucasoid patients

The computed tomographic (CT) features in 10 patients with moyamoya disease have been analysed. The scan findings were correlated with the corresponding angiographic profile and the stage of the vascular disease. Multiple infarcts (82%), abnormal enhancement patterns (50%) and cerebral atrophy (60%) were the frequent abnormalities detected. Though the abnormalities on scan did not correlate entirely with the angiographic and the clinical profiles, the CT Scans were most frequently abnormal in later stages of the disease (Stages-4 and 5). No scan abnormalities were detected in the territory of the posterior circulation.

Comparison of antigenic and allergenic components of Holoptelea integrifolia pollen collected from different source materials

Antigenic extracts prepared from pollen samples collected at weekly intervals during the same season did not exhibit significant variation in protein concentration. Stored pollen samples from different years, however, showed highly significant variations in protein concentration. The protein content of samples from different ecozones of India also varied (CV = +/- 32%). The IEF and SDS-PAGE patterns were almost identical in samples from the same season, but were variable in the samples stored from different years and different parts of India. IgE binding proteins from different samples also varied depending on the overall protein profiles. Almost all the patients, however, showed IgE binding to four proteins at 50, 60, 66 and 70 kD, indicating the important allergenic components of Holoptelea integrifolia.

Formation of plantlets through somatic embryogeny in the Himalayan blue poppy, Meconopsis simplicifolia (Papaveraceae)

Exuberant and subculturable calli could be induced from only hypocotyl and leaf segments of ca 4-month-old seedlings of Meconopsis simplicifolia cultured on Murashige & Skoog's medium supplemented with 10(-6)M kinetin + 10(-5)M α -naphthalene acetic acid. Suspension cultures were initiated from the calli in a similar medium but with 10(-5)M 2,4-dichlorophenoxy acetic acid in place of α -naphthalene acetic acid. In ca 80% of the suspension cultures somatic embryos differentiated freely (80-85%) as well as on the surface of small clumps of tissue (15-20%). Somatic embryos that developed beyond heart-shaped stage were transferred to agar-solidified Murashige & Skoog's medium free of growth substances. When maintained in 10 h light and 14 h dark the somatic embryos developed into plantlets bearing cauline leaves. From seed sowing to raising normal plantlets via callus required 28 weeks; on average 80 plantlets were obtained from one explant in three passages.

Head-high, airborne pollen grains from different areas of metropolitan Delhi

A survey of airborne pollen grains from four zones of metropolitan Delhi was conducted for 1 year (February 1988-January 1989) at human height level (5'-6'). Sampling was carried out in different inhabited areas in the four zones using Burkard Volumetric Personal Samplers. Sampling was carried out at weekly intervals, three times a day (7, 14, & 20 h) for 15 min. Poaceae, Ricinus, Cheno-Amaranth, Morus, Artemisia, Myrtaceae, Parthenium, Prosopis and Cannabis are important pollen contributors to the atmosphere, especially at lower heights. In general, pollen concentration was low at human height. Quantitative zonal variations have been recorded within an urban city.

Survey of atmospheric pollen allergens in Delhi: seasonal periodicity

Atmospheric pollen surveys were conducted at four different zones within the metropolitan capital city of India, Delhi, for a period of three years (1973-1975). Durham's Gravity Sampling Device was employed for sampling airborne pollen. Altogether 86 pollen types were identified from the atmosphere of Delhi; 22 types are new records for the atmosphere of Delhi. Two major pollen seasons--February to April and August to October--are recognized for Delhi. The atmosphere pollen concentration of different types as well as of the total counts showed significant annual and seasonal variations and also revealed marked differences in the quality and quantity of the pollen from site to site. Habitat factors seem to be the causal agents for the wide range of variations in the pollen content of the atmosphere of Delhi. The results of the survey are discussed in the light of relevant published literature.

Studies on pollen allergy in Delhi. Diurnal periodicity of common allergenic pollen

The volumetric sampling of the air has been carried out with the Suction Impaction Sampler devised by Tilak & Kulkarni (1970). The pollen counts have been expressed as number per cubic metre volume of the air. Based on the percentage of pollen peaks, diurnal patterns of the total count of all the types, and six dominant allergens have been determined. For these allergens, daily fluctuations have also been recorded. The influence of meteorological factors such as temperature, wind, rainfall, relative humidity and sunshine hours/day on the variation patterns in the concentration of atmospheric pollen has been discussed. It has been shown that 25-30 degrees C temperature, 5-15 km/h wind speed, 60-70% RH, bright sunny and rain-free days are favourable for high pollen catch. These weather conditions might be conducive for the high discharge, dispersal, and deposition of air-borne pollen. Too low or too high temperature, very high wind speed, high humidity, and cloudy and rainy days hinder high pollen catch.

Allergenic factors and symptomatology of respiratory allergy patients

An attempt has been made in the present study to find out the relationship between the symptomatology of nasobronchial allergy patients of Delhi with markedly positive skin reactions and prevalence of total pollen concentration in the atmosphere, concentration of major individual pollen types, total fungal spores and house dust mites together with climatic factors such as mean monthly temperature and relative humidity. A statistically significant correlation was not found between symptomatology of the patients of Delhi and mean monthly relatively humidity, atmospheric concentration of pollen, fungal spores and house dust mites. A significant negative correlation was observed between symptomatology of patients and mean monthly temperature. Except for the pollen of prospis which showed significant positive correlation with the symptomatology of Delhi patients, a significant positive correlation was absent with respect to other individual pollen types.

Loss of epinephrine stimulated synthesis of cyclic adenosine 3':5' monophosphate during maturation of rabbit and human reticulocytes

The adenylate cyclase activity of rabbit reticulocytes is localized in the stroma. Rabbit reticulocytes are four times more active than mature erythrocytes in transforming in situ formed [14C] adenosine triphosphate into [14C] cyclic adenosine 3':5'-monophosphate. Similarly, anaemic human red blood cells show higher activity in effecting this transformation. The adenylate cyclase activity is stimulated by epinephrine, 40% in rabbit reticulocytes, and 70-80% in anaemic human RBC but not in erythrocytes. Both the reticulocytes and erythrocytes can bind [14C] epinephrine, but the reticulocytes bind a relatively large amount. A glycogen phosphorylase that can be activated by cyclic adenosine 3':5'-monophosphate is detected only in reticulocytes. Both reticulocytes and erythrocytes contain a phosphodiesterase which can hydrolyse cyclic 3':5'-adenosine monophosphate and which is activated by imidazole and inhibited by methyl xanthines.