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PubMed1975

Carbohydrate binding specificity of the lectin from the pea (Pisum sativum).

Hapten inhibition measurements on the precipitin reaction between Pisum sativum lectin and Pichia pinus phosphomannan showed the lectin to bind D-mannose, D-glucose, D-fructose and L-sorbose. Unmodified hydroxyl groups at the C-4 and the C-6 positions of the D-glucopyranose ring were essential for binding to the protein. Modification of the C-2 hydroxyl group was allowed in the D-glucopyranose ring but not in the D-mannopyranose configuration. Substitution of the hydroxyl hydrogen atom at the C-3 position of D-glucose increased the binding efficiency. With the exception of gentiobiose, the beta-linked glycobioses tested were not bound to the lectin, whereas the alpha-linked glycobioses were potent inhibitorsmin general, the P. sativum lectin was found to be less sensitive to structural variation of inhibiting carbohydrates than concanavalin A, the lectin from Canavalia ensiformis.

Binding Sites↗

PubMed1990

Anti-influenza virus activity of synthetically polymerized phenylpropenoids.

Various dehydrogenation polymers (the so-called synthetic lignins) were synthesized from four different phenylpropenoids by endwise and bulk polymerizations and investigated for their anti-influenza virus activity. All of these materials suppressed the plaque formation of influenza virus infecting MDCK cells and the RNA-dependent RNA synthesis as effectively as the high molecular weight lignin-related extract (Fr. VI) of pine cone of Pinus parviflora Sieb. et Zucc. The structural simplicity and higher solubility of the synthesized polymers suggest that they might be regarded as potential candidates for medicinal antiviral resources.

Antiviral Agents↗

PubMed1992

Pine stilbene synthase cDNA, a tool for probing environmental stress.

Stilbene synthase cDNAs were isolated from a pine (Pinus sylvestris) cDNA library. Poly(A)+RNA required for the preparation was obtained from young seedlings challenged with Botrytis cinerea. A full-length cDNA encoding pinosylvin-forming stilbene synthase was sequenced, and the deduced amino acid sequence was compared with sequences of resveratrol-forming stilbene synthases. The cDNA coding for the key enzyme of pinosylvin formation is a valuable tool for detecting early effects of environmental stress in pine needles.

Acyltransferases↗

PubMed1996

Radiosensitivity of haplont yeast cells irradiated with sparsely and densely ionizing radiations.

Five haploid and three diploid yeast strains of various species (Yarrowia lipolytica, Pichia pinus and Pichia guilliermondii) were irradiated with alpha-particles from 239Pu and gamma-rays from 137Cs or 60Co in the stationary phase of growth. A common feature of these species is that they exhibit a haploid state as a normal vegetative state in natural conditions. It was shown that the transition from the haploid to the diploid state is not accompanied by increased radioresistance, and diploid strains were unable to perform liquid-holding recovery. The absence of diploid-specific recovery in diploid strains was also supported by the fact that the RBE of alpha-particles was almost identical for haploid and the corresponding diploid strains being much smaller than that observed in typical wild-type diploid strains capable of diploid-specific recovery. The results suggest that haplont yeast may have evolved to diplont yeast via the development of a specific repair system conferring specific resistance in the diploid state.

Alpha Particles↗

PubMed1995

Towards the specification of consecutive steps in macromolecular lignin assembly.

When Pinus taeda cell suspension cultures are exposed to 8% sucrose solution, the cells undergo significant intracellular disruption, irregular wall thickening/lignification with concomitant formation of an 'extracellular lignin precipitate. However, addition of potassium iodide (KI), an H202 scavenger, inhibits this lignification response, while the ability to synthesize the monolignols, p-coumaryl and coniferyl alcohols, is retained. Lignin synthesis (i.e. polymerization) is thus temporarily correlated with H202 generation, strongly implying a regulatory role for the latter. Time course analyses of extracellular metabolites leading up to polymer formation reveal that coniferyl alcohol, but not p-coumaryl alcohol, undergoes substantial coupling reactions to give various lignans. Of these, the metabolites, dihydrodehydrodiconiferyl alcohol, shonanin (divanillyl tetrahydrofuran) and its apparent aryl tetralin derivative, cannot be explained simply on the basis of phenolic coupling. It is proposed that these moieties are the precursors of so-called reduced substructures in the lignin macromolecule. This adds a new perspective to the lignin assembly mechanism.

Cell Wall↗

PubMed1981

The fate of fenitrothion in a stream environment and its effect on the fauna, following aerial spraying of a Scottish forest.

In order to control an infestation of Pine Beauty moth (Panolis flammea Schiff.) fenitrothion was applied at a rate of 300 g ha-1 to a forest plantation consisting primarily of Lodgepole Pine (Pinus contorta Loud.) and Sitka Spruce (Picea sitchensis Carriere) using the ultra-low volume spraying technique. The concentration of fenitrothion in the forest stream rose to a maximum of 18 micrograms l-1 within the treated area an hour after spraying, but fell to 0.5 microgram l-1 after 24 hs. There was no evidence that the resident fish population was disturbed by the treatment and no short term effects were noticeable in caged fish. The concentration--time profile in the fish followed closely the profile in the water, and in each of the four fish tissues studied fell to 0.02 mg kg-1 after 24 hs. Invertebrate drift increased markedly 12--16 hs after spraying, but decreased to around pre-treatment levels within 48 hs. Caged insects remained alive during the five-day post-spray observation period, suggesting that drifting insects were displaced rather than killed by the insecticide. Concentration of fenitrothion in Willow Moss (Fontinalis antipyretica) fell from 0.139 mg kg-1 to 0.003 mg kg-1 (wet weight) after 48 hs. Fenitrothion was not detected in sediment but this was possibly due to the low surface area/weight ratio of the particles.

Acetylcholinesterase↗

PubMed1990

Molecular evolution of plants as deduced from changes in free energy of 5S ribosomal RNAs.

The nucleotide sequence of Pinus silvestyris 5S rRNA was determined using two independent methods and compared with other plant 5S rRNAs. It shows more than 90% sequence homology with gymnosperm 5S RNAs. The free energy (delta G) analysis of 5S rRNAs from gymnosperms, angiosperms and the other higher plants revealed that the free energy of this ribosomal RNA decreases with evolution.

Base Sequence↗

PubMed1992

Germination of seeds from an irradiated forest: implications for waste disposal.

Jack pine (Pinus banksiana Lamb.) retain their seeds from year to year, so that in an irradiated forest, each tree receives a specific dose rate but has seeds that have accumulated a range of total doses. The Field Irradiator-Gamma facility in Pinawa, Manitoba, contains jack pine that have been irradiated longer and at lower dose rates than previously reported. Seed germination and germination rate were examined on seeds irradiated on the parent tree for up to 5 years. Germination rate was most sensitive and showed deleterious effects at 1.1 mGy hr-1. This is not much lower than results reported by others in shorter-term studies. Effects were related to dose rate rather than total dose. Hormesis, indicated by statistically significant increased germination rate, was evident at 0.6 mGy hr-1. To put these results into context, the concentrations of selected radionuclides that, through internal contamination, would deliver 1.1 mGy hr-1 to plants were estimated. For 99Tc and 129I, these concentrations are far above the chemical toxicity thresholds for plants. Clearly, as assessments of waste repositories begin to consider effects on organisms other than humans, such as plants, chemical toxicity will be an important feature.

Dose-Response Relationship, Radiation↗

PubMed1990

Inhibition of influenza virus infection by pine cone antitumor substances.

The anti-influenza virus activity of polysaccharides and other high molecular weight fractions from pine cone extract (PCE) of Pinus parviflora Sieb. et Zucc. was investigated. None of the fractions affected the growth of MDCK cells. The acidic PCE substances markedly suppressed the growth of the influenza virus in MDCK cells. Significant inhibition of both the viral protein synthesis in infected cells and virion-associated RNA-dependent RNA polymerase activity was observed with these acidic fractions. Although amantadine inhibited virus plaque formation as effectively as PCE fractions, it was less effective in inhibiting the RNA polymerase activity. These results suggest that PCE, which has been shown to contain antitumor substance(s), also contains anti-influenza virus substance(s).

Amantadine↗

PubMed1991

Possible involvement of lignin structure in anti-influenza virus activity.

Commercial lignins suppressed the growth of influenza A virus infecting MDCK cells, and the RNA-dependent RNA synthesis, as efficiently as the high-molecular weight fractions extracted from pine cone of Pinus parviflora Sieb. et Zucc. The anti-influenza A virus activity of both pine cone extract and commercial alkali-lignin was considerably reduced by treatment with sodium chlorite, but was not affected by sulfuric acid or trifluoroacetic acid. The degraded components of lignin, various synthesized polyphenols unrelated to lignin, and natural and chemically modified glucans, were not appreciably inhibitory. The data suggest that the polymerized phenolic structure of lignified materials is responsible for the anti-influenza A virus activity.

Animals↗

PubMed1992

Purification and characterization of wheat and pine small basic protein substrates for plant calcium-dependent protein kinase.

A wheat basic protein (WBP) was purified to homogeneity from wheat germ by a protocol involving extraction, centrifugation, batchwise elution from carboxymethylcellulose (CM-52), acidification with trifluoroacetic acid, neutralization and HPLC on a SP5PW cation exchange column. WBP is a 10 kDa protein and is phosphorylated on serine residues by wheat germ Ca(2+)-dependent protein kinase (CDPK). [32P]phosphoWBP exactly comigrates with WBP on SDS-PAGE. WBP does not inhibit either wheat germ CDPK or calmodulin-dependent myosin light chain kinase. Apart from histone H1, WBP is the best endogenous substrate yet found for wheat embryo CDPK. A 12 kDa pine basic protein (PBP) was purified to homogeneity from seeds of stone pine (Pinus pinea L.) by a simple procedure involving batchwise elution from carboxymethylcellulose and cation exchange HPLC. PBP is also a good substrate for CDPK and is phosphorylated on Ser residues. N-terminal sequencing of WBP and PBP revealed that these proteins are homologous to a family of small basic plant proteins having a phospholipid transfer function.

Amino Acid Sequence↗

PubMed1988

Effect of elemental sulphur on the vegetation of a Lodgepole pine stand.

Shrub and herb cover decreased 98% and diversity 76% after particulate elemental sulphur was deposited in a Pinus contorta Loudon var. latifolia Engelm. forest in west-central Alberta, Canada. Decreases were measured over four years and, initially, were greater for the herbs than they were for the shrubs. The decline in the herbs occurred one year before decreases in half the shrub species. The dramatic decline of the vegetation appeared related to the changes in the soil chemistry of the surface organic horizon following the oxidation of elemental sulphur.

Journal Article↗

PubMed1989

Acid mist and ozone effects on the leaf chemistry of two western conifer species.

Seedlings of Jeffrey pine (Pinus jeffreyi) and giant sequoia (Sequoiadendron gigantea) were more susceptible to leaf chemical changes following exposure to acid mist (pH 3.4-2.0) or acid mist/ozone combinations, than to ozone alone (0.1-0.2 microl/litre), when plants were exposed to alternating doses of these pollutants for 6-9 weeks. Under acid mist treatment, leaves exhibited higher levels of nitrogen and sulfur, two elements applied in acid mist. In addition, levels of foliar sodium, and, in the case of giant sequia, potassium, as well, increased under acid mist treatment. Iron and manganese were also mobilized, resulting in significant increases in these elements in pine, and decreases in manganese in giant sequoia foliage. The acid treatment also reduced chlorophyll b concentrations in pine, and, to a less significant extent, in giant sequoia. Calcium, magnesium, barium and strontium were differentially accumulated in giant sequoia compared to Jeffrey pine. Under acid mist treatment, all of these elements (except strontium) declined in concentration in giant sequoia, with calcium showing the most significant trend. The more extensive changes in leaf chemistry induced by acid mist are consistent with earlier observations of significant changes in spectral reflectance of these seedlings after 3 weeks of fumigation. Limited foliage samples collected from these two species in 1985 and 1986 in Sequoia/Kings Canyon National Parks in the southern Sierra Nevada do not in themselves indicate any clearcut or severe effects of ozone alone on leaf chemistry of these species, but a mild influence of nitrate-laden acid deposition, possibly in combination with ozone, is consistent with the rise in nitrogen and lignin levels in Jeffrey pine on sites observed to have moderate visible injury symptoms. No firm conclusions about effects of pollutants on leaf chemistry in these field sites is possible without further study.

Journal Article↗

PubMed1989

Regional variation in surface properties of Norway spruce and scots pine needles in relation to forest decline.

Measurements of leaf wettability (contact angle), amounts of epicuticular wax and of surface dust are reported for Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L) Karst) trees growing at 12 sites in Europe from SW Germany to NE Scotland. At each site, three year classes (current year, 1 and 2-year-old) of needles were sampled from the mid-crown of up to 12 trees. Trees were selected at random from two strata, those showing visible decline symptoms (i.e. loss of needles or discoloration) and those apparently healthy. Needles for analysis were taken from apparently healthy (green) shoots in both cases. There were no significant differences between 'declining' and 'healthy' trees within sites, suggesting that leaf surface properties reflect environmental exposure rather than plant response. There were significant differences between sites, particularly for Norway spruce, which may be related to environmental factors including air pollution. Contact angles were consistently smaller at low-altitude sites in Britain and The Netherlands than at high-altitude sites in Germany where forests show decline symptoms. Leaf wettability decreased (contact angles increased) with wax amount and increased with dust amount. Leaf surface properties integrate environmental influences over long periods, and may be useful in identifying sites 'at risk' of developing decline symptoms, but causal relationships cannot be deduced without further direct experimentation.

Journal Article↗

PubMed1990

Nutrient accumulation in trees and soil following irrigation with municipal effluent in Australia.

Irrigation of tree crops is being evaluated as a method of land disposal of municipal effluent in Australia. A study was carried out from 1980-84 in which seven tree species were sprinkler-irrigated with effluent at an annual rate of 1191-1752 mm. Effective weed control and frequent irrigation resulted in good survival of all species (range 83-100%) at 12 months. Total productivity was estimated at age 4 years by measuring biomass of each species inclusive of litter and roots to a soil depth of 80 cm. Biomass production of the high-yielding species, flooded gum (Eucalyptus grandis) and Sydney blue gum (E. saligna), was around 10 kg m(-2). Percentage leaf mass of these species was small (8-9%) compared with 25% and 29% for the relatively slow-growing river she-oak (Casuarina cunninghamiana) and radiata pine (Pinus radiata). Accumulation of nutrients in the total biomass differed significantly between species and ranged from 34-54 g m(-2) for nitrogen, 4.0-10.4 g m(-2) for phosphorus, 2.1-12.2 g m(-2) for sodium, 22-34 g m(-2) for potassium, 12-61 g m(-2) for calcium and 4.7-9.3 g m(-2) for magnesium. River she-oak and river red gum (E. camaldulensis), because of their relatively large crown and litter masses, accumulated more nitrogen, phosphorus, potassium and calcium than flooded gum or Sydney blue gum. Chemical properties of soils (0-150 cm) were measured in 1980 and again in 1984. Irrigation significantly increased pH (by around 1 unit), throughout the profile. Concentrations of total phosphorus, and exchangeable sodium, calcium and magnesium were increased in the upper profile. Overall, soil chemical properties were not adversely affected by effluent irrigation over the 4-year period, though there was a trend towards more sodic conditions in the soil profile. Nutrient accumulation in soil occurred mainly in the 0-35 cm depth, coinciding with the main root zone of the trees. Renovation of the effluent was therefore estimated as the amount of each nutrient accumulated in the biomass (averaged over the seven species) plus soil (0-35 cm), expressed as a percentage of amount applied in irrigation over the 4 years; that is, nitrogen, 29%; phosphorus, 78%; sodium, 15%; potassium, 26%; calcium, 98% and magnesium, 54%.

Journal Article↗

PubMed1990

Growth, ectomycorrhizae and nonstructural carbohydrates of loblolly pine seedlings exposed to ozone and soil water deficit.

Loblolly pine (Pinus taeda) seedlings from three full-sib families were exposed to 0, 50, 100 or 150 ppb ozone (O(3)) (5 h/d, 5 d/week for 6 or 12 weeks). Soil water potential was maintained near pot capacity (-0.03 MPa) or soil was allowed to dry to approximately -1.0 MPa and resaturated. Chlorotic mottling and flecking of needles due to O(3) injury were observed for seedlings from all pine families. Soil water deficit lessened the intensity of O(3) symptoms, possibly due to stomatal closure. Exposure to O(3) and soil water deficit each resulted in less seedling volume growth and dry weight, and changed the nonstructural carbohydrate content of seedlings compared with controls. Increasing O(3) concentrations resulted in a linear reduction in foliar starch content but did and affect hexose or sucrose content. Soil water deficit resulted in less starch and soluble sugar contents in above- and below-ground plant parts compared with controls. Soil water deficit did not affect numbers or percentages of roots that formed ectomycorrhizal tips. A linear dose-response relationship between O(3) and ectomycorrhizae was observed. The number of ectomycorrhizal tips/cm long root and the percentage of feeder roots that formed ectomycorrhizae were lower as O(3) concentration increased. Overall, each stress alone caused less seedling growth and carbohydrate content compared with controls, but only O(3) was responsible for suppression of ectomycorrhizae.

Journal Article↗

PubMed1990

Ozone alters carbon allocation in loblolly pine: assessment with carbon-11 labeling.

Loblolly pine (Pinus taeda L.) seedlings were exposed to 0.120 micromol mol(-1) (ppm) ozone for 7 h per day, 5 days per week for 12 weeks. No visible damage resulted from this regime. A short-lived radioisotope of carbon ((11)C) was used to characterize changes in plant physiology caused by ozone, the first time this technique has been used for ozone exposure studies. In comparison to plants kept in charcoal-filtered air, pines exposed to ozone exhibited reductions in photosynthesis (16%), speed of phloem transport (11%), phloem photosynthate concentration (40%) and total carbon transport toward roots (45%). Photosynthate not transported to the roots appeared to accumulate in the stems. Primary branches of pines exposed to ozone were some 50-60% heavier than those of control pines. Ozone was thus shown to have a significant short-term impact on phloem transport processes that results in a shift in allocation of photosynthate favoring stems.

Journal Article↗

PubMed1990

Effects of photochemical smog and mineral nutrition on ponderosa pine seedlings.

Two-year-old seedlings of ponderosa pine (Pinus ponderosa Dougl. ex Laws) were exposed to ambient concentrations of photochemical smog (AA) and clean air (CA) during a single field season at Tanbark Flat of the San Gabriel Mountains in the Los Angeles Basin. The seedlings were grown in a perlite-vermiculite medium with full supply of nutrients (based on modified Hoagland solution); reduced to 50% supply of N; reduced to 50% supply of Mg; and reduced to 50% supply of N+Mg. No significant effects of air pollution exposures on injury development, stem growth and concentrations of plant pigments were determined. The seedlings in the AA treatment had decreased N concentration in current year needles compared with CA seedlings; however, the needle concentrations of other elements did not change. Reduction of N supply in the growing medium caused decreased N, P, Ca, K and chlorophyll a concentrations in needles. Stem growth of the seedlings with reduced N supply was significantly decreased as well. No changes in stem growth or chemical composition of plants with reduced Mg supply were noted. Reduction of supply of nutrients did not change responses of trees to the air pollution exposures.

Journal Article↗

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