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PubMed2006

Tomato seed germination: regulation of different response modes by phytochrome B2 and phytochrome A.

Lycopersicon esculentum seeds germinate after rehydration in complete darkness. This response was inhibited by a far-red light (FR) pulse, and the inhibition was reversed by a red light (R) pulse. Comparison of germination in phytochrome-deficient mutants (phyA, phyB1, phyB2, phyAB1, phyB1B2 and phyAB1B2) showed that phytochrome B2 (PhyB2) mediates both responses. The germination was inhibited by strong continuous R (38 micromol m(-2) s(-1)), whereas weak R (28 nmol m(-2) s(-1)) stimulated seed germination. Hourly applied R pulses of the same photon fluence partially replaced the effect of strong continuous R. This response was called 'antagonistic' because it counteracts the low fluence response (LFR) induced by a single R pulse. This antagonistic response might be an adaptation to a situation where the seeds sit on the soil surface in full sunlight (adverse for germination), while weak R might reflect that situation under a layer of soil. Unexpectedly, the effects of continuous R or repeated R pulses were mediated by phytochrome A (PhyA). We therefore suggest that low levels of PhyA in its FR-absorbing form (Pfr) cause inhibition of seed germination produced either by extended R irradiation (by degradation of PhyA-Pfr) or by extended FR irradiation [keeping a low Pfr/R-absorbing form (Pr) ratio].

Germination↗
PubMed2006

[The acerola fruit: composition, productive characteristics and economic importance].

The acerola (Malpighia emarginata Sessé y Mociño ex DC) is a wild plant grown in zones of tropical and subtropical climate. Acerola is origin from South of Mexico, Central America and Septentrional area of South America. Its scientific name was adopted in 1986 by the International Council of Vegetable Genetic Resources. Malpighia emarginata has a subglobulose drupa fruit with three seeds which account between the 19 - 25% of the total weight. The diameter and weight of the fruit varies between 1 - 4 cm and 2 - 15 g, respectively. The fruit shows green color when it is developing, which changes to yellow and red tones when it is mature. Each plant produces annually 20 - 30 kg of fruits. This fruit contents macro and micronutrients: proteins (0.21-0.80 g/100 g), fats (0.23-0.80 g/100 g), carbohydrates (3.6-7.80 g/100 g), mineral salts (iron 0.24, calcium 11.7, phosphorus 17.1 mg/100 g) and vitamins (thiamine 0.02, riboflavine 0.07, piridoxine 8.7 mg/100 g). Its high content in vitamin C (695 a 4827 mg/100 g) is remarkable, therefore acerola has an increasing economic value by its great consume during last years. Acerola also presents carotenoids and bioflavonoids which provide important nutritive value and its potential use as antioxidant. Brazil has a climate and soil appropriate for the culture of acerola, thus this country is the main mundial productor. Acerola is commercialised as juices, jams, ices, gelatins, sweets or liquors. Bibliographical data have been mainly supplied by Electronic Resources of the University of Seville and the University do Vale do Itajaí (Santa Catarina, Brazil).

Antioxidants↗
PubMed1997

Calcium dependence and binding in cultures of Histoplasma capsulatum.

Histoplasma capsulatum is a pathogenic fungus with two distinct morphologies and lifestyles. The saprophytic form of this organism, a mold, thrives in soil and is especially abundant in the Ohio and Mississippi River valleys. Its parasitic counterpart, a yeast, colonizes phagolysosomes of mammalian macrophages. We have observed a major difference in the calcium requirements of the two forms of Histoplasma, potentially implicating the phagolysosome as a calcium-limiting compartment. Deprivation of calcium by the addition of EGTA to culture media inhibited the growth of mycelial H. capsulatum but had no effect on yeast growth in vitro. In addition, yeasts released a calcium-binding protein (CBP) detectable by a 45CaCl2 blotting technique. CBP was a major component of yeast culture supernatant and was also detectable by ruthenium red staining, another assay for calcium-binding activity. Conversely, mycelial H. capsulatum did not produce CBP, a finding that correlates with the dependence of mycelia on calcium for growth. We also describe here the purification of CBP from yeast culture supernatant by reversed-phase high-pressure liquid chromatography.

Calcium↗
PubMed2005

Spatial patterns of cadmium and lead deposition on and adjacent to National Park Service lands in the vicinity of Red Dog Mine, Alaska.

Heavy metal escapement associated with ore trucks is known to occur along the DeLong Mountain Regional Transportation System (DMTS) haul road corridor in Cape Krusenstern National Monument, northwest Alaska. Heavy metal concentrations in Hylocomium splendens moss (n = 226) were used in geostatistical models to predict the extent and pattern of atmospheric deposition of Cd and Pb on Monument lands. A stratified grid-based sample design was used with more intensive sampling near mine-related activity areas. Spatial predictions were used to produce maps of concentration patterns, and to estimate the total area in 10 moss concentration categories. Heavy metal levels in moss were highest immediately adjacent to the DMTS haul road (Cd > 24 mg/kg dw; Pb > 900 mg/kg dw). Spatial regression analyses indicated that heavy metal deposition decreased with the log of distance from the DMTS haul road and the DMTS port site. Analysis of subsurface soil suggested that observed patterns of heavy metal deposition reflected in moss were not attributable to subsurface lithology at the sample points. Further, moss Pb concentrations throughout the northern half of the study area were high relative to concentrations previously reported from other Arctic Alaska sites. Collectively, these findings indicate the presence of mine-related heavy metal deposition throughout the northern portion of Cape Krusenstern National Monument. Geospatial analyses suggest that the Pb depositional area extends 25 km north of the haul road to the Kisimilot/Iyikrok hills, and possibly beyond. More study is needed to determine whether higher moss heavy metal concentrations in the northernmost portion of the study area reflect deposition from mining-related activities, weathering from mineralized Pb/Zn outcrops in the broader region, or a combination of the two. South of the DMTS haul road, airborne deposition appears to be constrained by the Tahinichok Mountains. Heavy metal levels continue to diminish south of the mountains, reaching a minimum in the southernmost portion of the study area near the Igichuk Hills (45 km from the haul road). The influence of the mine site was not studied.

Alaska↗
PubMed1984

Properties of salicylate hydroxylase and hydroxyquinol 1,2-dioxygenase purified from Trichosporon cutaneum.

Salicylate hydroxylase (salicylate 1-monooxygenase, EC 1.14.13.1) was purified from the soil yeast Trichosporon cutaneum. The enzyme contained flavin adenine dinucleotide and was monomeric, with a molecular weight of 45,300. In addition to salicylate, the four isomeric dihydroxybenzoates having one hydroxyl adjacent to carboxyl in the benzene nucleus were oxidatively decarboxylated without formation of hydrogen peroxide. One of these isomers, gentisate, was rapidly oxidized to hydroxyquinol by the enzyme but did not serve as an effective single carbon source for T. cutaneum; however, when growing with salicylate, cells also readily utilized gentisate for growth. Hydroxyquinol 1,2-dioxygenase (EC 1.13.11....) is a newly investigated enzyme which was purified from T. cutaneum grown with 4-hydroxybenzoate. The enzyme was red, contained ferric iron, and was specific for hydroxyquinol; catechol and pyrogallol were oxidized at less than 1% of the rate for hydroxyquinol, and no activity could be detected against seven other catechols. The enzyme was composed of two nonidentical subunits having molecular weights of 39,600 and 38,200 and was apparently dimeric.

Dioxygenases↗
PubMed1987

Invasive aspergillosis in children.

Aspergillosis may complicate the course of the child in an immunocompromised state. When sinus or pulmonary infections present in immunocompromised children, one third of these patients are diagnosed accurately premortem as resulting from aspergillosis and two thirds remain undiagnosed. Mortality remains quite high, despite prompt treatment. Four children in our hospital during the last 4 years have had invasive aspergillosis presenting other than sinus or pulmonary infections. Each presented with extensive soft tissue infection. Three presented after traumatic devascularizing injuries to the leg in which massive soil and fecal contamination occurred. One child presented with absolute neutropenia secondary to treatment of acute lymphocytic leukemia. The child had a chest wall lesion develop at the site of an EKG electrode. All patients had a punctate black skin lesion with a halo of intense erythema surrounded by a zone of blanching. These lesions rapidly expanded. Initial extensive debridement of the lesions, combined with systemic chemotherapy with amphotericin B failed to halt the progression of the disease. Histology showed vascular invasion with hyphal forms. Each patient then responded well to radical debridement (three hemipelvectomies and one chest well resection). The child in an immunocompromised state who develops a red papule, then a black eschar with surrounding erythema, should have immediate biopsy that can easily demonstrate the characteristic hyphal forms. Early radical surgical debridement and antifungal therapy can be lifesaving. The initial debridement should include tissues well beyond any apparent involvement.

Amphotericin B↗
PubMed1997

Environmental pollution and child health in the Aral Sea region in Kazakhstan.

The deterioration of human health with increasing infant mortality rate, declining life expectancy at birth and increasing prevalence of serious infectious diseases in Russia and other former Soviet Republics is thought to be due to a combination of several factors such as inadequate nutrition, poor sanitation, collapse of the health care system and pollution from Soviet agriculture and industries. In the Aral Sea region in Kazakhstan, the environmental problems are of near catastrophic proportions. As a result of the implementation of a massive irrigation scheme to support the cotton fields in the former desert land, the water flow to the Aral Sea was reduced to less than half. Industrial pollutants such as PCB-compounds and heavy metals, but also the use of large quantities of pesticides to control parasites and weeds have accumulated not only in water, but also in soil and have been deposited over large areas by atmospheric transport to enter the food chain leading to humans. In a study of 15 children and of an additional 12 children referred from the region of the Aral Sea to the National Children's Rehabilitation Center in Almaty with symptoms and signs of 'ecological disease', we have found that the concentration of PCB compounds in the blood lipids is elevated in relation to healthy Swedish children. In addition, the blood lipid concentration of the beta-isomer of the hexachlorocyclohexanes was extremely high and of DDT-compounds was elevated up to 20 times. The concentrations of lead in red blood cells was moderately elevated and that of cadmium slightly elevated compared to the findings in Stockholm children. To study the role of these pollutants in the diseases found in children from the Aral Sea region accurate epidemiological studies have to be performed.

Adolescent↗
PubMed1989

[Determination of elements hazardous to health in vegetables grown in the Siedlece district].

In the years 1986-1987 the content of iron, manganese, zinc, copper, nickel, lead and cadmium was determined by the atomic absorption spectrometry method in vegetables grown by gardeners in Wegrów, Sokołów Podlaski and Siedlce. These elements were measured in cabbages, tomatoes, carrots, parsley, celery (root and leaves), red beet and potatoes. The content of lead in these vegetables was from 0.0 to 0.596 mg/kg, and that of cadmium was from 0.002 to 0.184 mg/kg (fresh mass). The level of cadmium in many samples of vegetables exceeded to limit permitted by the Polish Ministry of Health. Lead level in a sample of parsley leaves was two times above the permitted value.

Agriculture↗
PubMed1981

A red Beneckea from Laguna Figueroa, Baja California.

A new bacterium (nitrate-respiring, prodigiosin-producing, marine curved rod with a sheathed flagellum) has been isolated from anaerobic mud underlying a microbial meat. This brightly pigmented red bacterium, referred to as strain BV1 (Baja California vibrio, isolate 1) was taken from a closed, hypersaline basin at Laguna Figueroa (or Laguna Mormona), Baja California de Norte, Mexico. It is closely related to the recently described Beneckea gazogenes (Harwood, 1978), which was isolated from an estuarine habitat, the Sippewissett salt marsh at Woods Hole, Massachusetts, U.S.A. Strain BV1 and B-gazogenes are both oxidase positive facultative anaerobic curved rods which bear a single polar flagellum, and synthesize the red-orange tri-pyrrole pigment prodigiosin. The bacterium, which fluoresces green when excited with UV light (lambda = 455 nm), deposits pigment extracellularly in copious quantities. The extracellular pigment deposits fluoresce red-yellow. Both BV1 and B. gazogenes are able to grow utilizing xylose, cellobiose or arabinose, products of plant biosynthesis, as sole carbon sources. BV1 differs from B. gazogenes in cell size, pattern of pigment production, nutritional characteristics, the ability to perform anaerobic respiration using nitrate as a terminal electron acceptor, sensitivity to a newly discovered lytic phage and to the antibiotic vibriostat O/129.

Anaerobiosis↗
PubMed2005

Changed isoflavone levels in red clover (Trifolium pratense L.) leaves with disturbed root nodulation in response to waterlogging.

The effect of disturbed root nodulation on the quantitative and qualitative composition of the main isoflavonoid glucoside malonates, glucosides, and aglycones in the leaves of Trifolium pratense L. grown under waterlogging conditions was investigated. Isoflavonoids are involved in the regulation of root nodule activity and the establishment of the mycorrhizal association. Isoflavonoid determination was performed using reversed-phase liquid chromatography coupled to mass spectrometric and UV absorbance detection. In response to waterlogging, the concentrations of biochanin A and biochanin A-7-O-glucoside malonate, biochanin A-7-O-glucoside, and genistein-7-O-glucoside in the leaves increased two- to threefold after a lag period of 3 wk because of disturbed root nodulation. The other isoflavones detected formononetin, formononetin-7-O-glucoside malonate, and formononetin-7-O-glucoside-did not show any significant changes related to waterlogging. After restoring normal soil water conditions, the concentrations of biochanin A and its glucoside and glucoside-malonate rapidly returned to the initial values, whereas the concentration of genistein-7-O-glucoside remained high.

Adaptation, Physiological↗
PubMed2004

Sequential extraction of heavy metals in river sediments of an abandoned pyrite mining area: pollution detection and affinity series.

In this paper heavy metal pollution at an abandoned Italian pyrite mine has been investigated by comparing total concentrations and speciation of heavy metals (Fe, Cu, Mn, Zn, Pb and As) in a red mud sample and a river sediment. Acid digestions show that all the investigated heavy metals present larger concentrations in the sediment than in the tailing. A modified Tessier's procedure has been used to discriminate heavy metal bound to organic fraction from those originally present in the mineral sulphide matrix and to detect a possible trend of metal mobilisation from red mud to river sediment. Sequential extractions on bulk and size fractionated samples denote that sediment samples present larger percent concentrations of the investigated heavy metals in the first extractive steps (I-IV) especially in lower dimension size fractionated samples suggesting that heavy metals in the sediment are significantly bound by superficial adsorption mechanisms.

Adsorption↗
PubMed2006

Morphology and biochemistry of non-glandular trichomes in Cistus salvifolius L. leaves growing in extreme habitats of the Mediterranean basin.

Here the functional roles of stellate and dendritic trichomes in Cistus salvifolius L leaves were studied by analysing i) both leaf surface and trichome morphology using scanning electron and light microscopy; and ii) the composition and localisation of polyphenols by coupling liquid chromatography with fluorescence spectroscopy and fluorescence microimaging. Red-coloured compounds were detected in the stalk cells and the channel in the trichome arm, and appeared to be released at the tip end of the trichome branch. We identified such metabolites as ellagitannins, namely punicalagin and two galloyl derivatives of punicalagin. These ellagitannins accounted for 4.3 % of leaf dry weight and their concentration in the leaf leachate averaged 289.4 mg L (-1). The trichome arms exhibited an appreciable orange-red autofluorescence (centred at 620 nm) when excited with UV light (at 365 nm) or emitted in the yellow waveband (peak centred at 566 nm) when stained with the Naturstoff reagent, and excited at 488 nm. The fluorescence signatures of the trichome arms were consistent with the presence of mono-hydroxy B-ring substituted flavonoids, which were identified as the mono- and di-coumaroyl derivative of a kaempferol 3-O-glycoside. Our data may provide some insights on the functional roles of stellate and dendritic trichomes in the response mechanisms of C. salvifolius to Mediterranean-type climate, based upon (i) the potential effect of released ellagitannins on the soil nitrogen dynamic and (ii) the ability of acylated kaempferol 3-O-glycosides to effectively absorb both the UV-B and UV-A wavelengths.

Chromatography, High Pressure Liquid↗
PubMed1962

Constancy of characteristics in the streptomycetes.

Sanchez-Marroquin, A. (University of Mexico, México D.F.). Constancy of characteristics in the streptomycetes. J. Bacteriol. 83:1183-1192. 1962.-A total of 150 Streptomyces strains isolated from soil was studied during a 3-year period in regard to constancy and variation of the following characteristics: sporophore micromorphology, color of the aerial and substrate mycelium, surface configuration of the spores, assimilation of carbon compounds, production of H(2)S and melanoid pigment, and reduction of nitrates. A remarkable constancy in the following characteristics was found: (i) sporophore micromorphology when only three of the seven morphological series of Pridham et al. were developed on tomato paste-oatmeal agar or yeast extract-malt extract agar; (ii) color of the aerial mycelium if only four fundamental colors are distinguished (white to cream or buff shades; yellow to orange or brown; pink to cinnamon, red or pinkish tan to lavender; and green to gray or blue); (iii) surface configuration of the spores divided in two types (smooth and warty to spinous or hairy); (iv) assimilation of five carbon compounds (arabinose, xylose, rhamnose, raffinose, and mannitol); (v) production of H(2)S on Difco peptone-iron agar supplemented with 0.1% Difco yeast extract; and (vi) production of melanoid pigment on peptone agar, giving similar results to those of the H(2)S test. Color of the substrate mycelium, size and shape of the spores, and reduction of nitrates should be used only as complementary data in the species descriptions, owing to their inconsistency and unreliability.

Actinomycetales↗
PubMed2006

Climate and environmental factors influencing Echinococcus multilocularis occurrence in the Slovak Republic.

During the period of 2000-2004, 3,096 red foxes from the whole territory of the Slovak Republic were sampled and examined parasitologically for infections with Echinococcus multilocularis, causative agent of serious alveolar echinococcosis in humans. Relations between prevalence of the parasite in individual regions of Slovakia and some environmental factors were weighted. During the study period, great differences of prevalence and infection intensity were found on a regional level and significant between-year fluctuation of both parameters was observed. High-endemic foci with an estimated prevalence of more than 30 % were detected in the northern and central part of the country. Climatic conditions, including low mean annual air temperature, high mean annual rainfall and the high humidity of the soil, showed to be important for E. multilocularis distribution. Significant correlation was calculated between prevalence of the tapeworm, mean annual precipitation values, and population density of small mammals.

Animals↗
PubMed2002

Geophagy as a correlate of folivory in red-handed howler monkeys (Alouatta belzebul) from eastern Brazilian Amazonia.

Howler monkeys, Alouatta spp., are the most folivorous of neotropical primates (Platyrrhini), although Amazonian red-handed howlers (Alouatta belzebul) are relatively frugivorous. The feeding ecology of a free-ranging group of A. belzebul was monitored at a site in eastern Brazilian Amazonia over a tenmonth period (November 1997 to August 1998). The first half of the study period encompassed the peak of the wet season, during which the study group's diet was predominantly frugivorous (scan sample records: 53.5% fruit, 40.8% leaves), and the second half, the transition from wet to dry season, characterized by a marked shift to folivory (18.9% fruit, 77.9% leaves). This shift was accompanied by a marked increase in mature, as opposed to flush leaves, which are relatively rich in secondary compounds. Ingestion of soil from termitaria was recorded on a total of 26 occasions, all of which occurred during the second half of the study period. Soil from termitaria was relatively rich in elements such as Ca and Na and in organic carbon, in comparison with that from the forest floor. The extent to which the monkeys ingested soil for their mineral supplements, or as an aid for the digestion of leaves, in particular the absorption of secondary compounds, remains unclear. The marked correlation with the observed patterns of folivory suggests that the latter function may have been the primary motive for geophagy in this species.

Alouatta↗
PubMed1983

The relative importance of uptake and surface adherence in determining the radionuclide contents of subterranean crops.

The adherence of Pu-bearing particles to external surfaces of carrots, turnips, red potatoes, and sweet potatoes accounted for greater than or equal to 93% of their total Pu content. Uptake, which was measured as Pu content in peeled crops, accounted for less than or equal to 7%. Plutonium concentrations in most peeled crops were below background, and consequently, uptake could not be conclusively demonstrated. However, uptake accounted for most of the 137Cs, 40K, and 226Ra contents of subterranean crops. Concentration ratios for total radionuclide contents (i.e. surface adherence plus uptake) ranged from 3.9 X 10(1) for 40K, to 1.1 X 10(-2) for 239, 240Pu. Approximately 1.5 X 10(-3) pCi 239, 240Pu adhered per cm2 of subterranean crop surface per 1 pCi Pu/g of soil.

Cesium Radioisotopes↗
PubMed1989

Competition among Strains of Rhizobium leguminosarum biovar trifolii and Use of a Diallel Analysis in Assessing Competition.

Competition between indigenous Rhizobium leguminosarum biovar trifolii strains and inoculant strains or between mixtures of inoculant strains was assessed in field and growth-room studies. Strain effectiveness under competition was compared with strain performance in the absence of competition. Field inoculation trials were conducted at Elora, Ontario, Canada, with soil containing indigenous R. leguminosarum biovar trifolii. The indirect fluorescent-antibody technique was used for the identification of nodule occupants. Treatments consisted of 10 pure strains, a commercial peat inoculant containing a mixture of strains, and an uninoculated control. Inoculant strains occupied 17.5 to 85% of nodules and resulted in increased dry weight and nitrogen content, as compared with the uninoculated control. None of the strains was capable of completely overcoming resident rhizobia, which occupied, on average, 50% of the total nodules tested. In growth-room studies single commercial strains were mixed in all possible two-way combinations and assessed in a diallel mating design. Significant differences in plant dry weight of red clover were observed among strain combinations. Specific combining ability effects were significant at the 10% level, suggesting that the effectiveness of strain mixtures depended on the specific strain combinations. Strains possessing superior effectiveness and competitive abilities were identified by field and growth-room studies. No relationship was detected between strain effectiveness and competitive ability or between strain recovery and host cultivar. The concentration of indigenous populations was not considered to be a limiting factor in the recovery of introduced strains at this site.

Journal Article↗
PubMed2001

Fluorescence and FT-IR spectroscopic studies of Suwannee River fulvic acid complexation with aluminum, terbium and calcium.

In this study fluorescence emission and IR spectroscopy have been used to investigate the interaction of the class A (oxygen seeking "hard acid") metal Al(3+), with Suwannee River fulvic acid. Addition of Al(3+) ion results in a significant enhancement in fulvic acid fluorescence emission (at lambda(em)=424 nm) and significant red shift of the excitation wavelength (from lambda(ex)=324 nm to lambda(ex)=344 nm) at low pH values (pH approximately 4.0-5.0). At pH 4.0 (0.1 M ionic strength), where the predominant aluminum ion species is the "free" (aquo) ion, the fulvic acid fluorescence reaches 142% of the value in the absence of added metal ion. Analysis of the pH 4.0 and pH 5.0 fluorescence enhancement data with the nonlinear (single site) model of Ryan and Weber indicated binding constants in the range of 4.67.10(4)-2.87.10(6) M(-1) and concentrations of ligand sites in the range of 18.6.10(-6)-24.0.10(-6) M, both consistent with previous studies performed on both aquatic and soil fulvic acids. Companion fluorescence experiments performed on two other class A metal ions, Ca(2+) and Tb(3+), indicated no significant enhancement or quenching with Ca(2+) and only slight quenching with Tb(3+). Comparison of FT-IR spectra collected on fulvic acid alone and fulvic acid in the presence of the three class A metals (Al(3+), Ca(2+) and Tb(3+)) provides strong evidence for the involvement of carboxyl carbonyl functions in the binding of all three metal ions, which is not unexpected. The spectra also reveal, however, a very pronounced difference in the 4000-2000 cm(-1) IR spectral region between the Al(3+) spectrum and the Ca(2+) and Tb(3+) spectra. The -OH stretch spectral region in the Al(3+) spectrum has a major component shifted to higher energy (compared to fulvic acid alone or to fulvic acid in the presence of Ca(2+) or Tb(3+)). Even more striking is the emergence of a pronounced IR band at 2407 cm(-1), which is present only in the Al(3+) spectrum. The results of fluorescence and IR experiments with the model compounds salicylic acid and phthalic acid further confirm that both salicylic acid-like sites and phthalic acid-like sites are likely complexation sites for Al(3+) in fulvic acid and are major contributors to the observed spectroscopic changes associated with Al(3+) ion complexation. From a comparison of both the fluorescence and IR spectral results for all three class A metals, differing most strongly in the value of their ionic index, it seems clear that major sources of the deviation in spectral properties between Al(3+) and Ca(2+)/Tb(3+) is the unusually high value of its charge density and relatively low propensity for involvement in covalent bonding interactions (very high ionic index and relatively low covalent index in the Nieboer and Richardson classification of environmental metals), as well as affinity for certain functional groups.

Aluminum↗