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11.
E. Baldini Osvaldo Facini Fabrizio Nerozzi Federica Rossi Annalisa Rotondi 《Trees - Structure and Function》1997,12(2):73-81
Light partition has been examined and evaluated on five woody species (Olea europaea, Ficus carica, Pittosporum tobira, Hedera helix maculata, Persica vulgaris) in relation to their leaf morpho-histological characteristics, water and chlorophyll contents. Leaf parameters and optical
properties (reflectance, transmittance, absorbance) in PAR, FR and NIR wavebands (400–1100 nm) were preliminarily submitted
to a canonical correlation analysis where lamina thickness and water content showed a leading role in determining all the
optical properties, while chlorophyll, influential in the PAR region, was remarkably effective only in an extreme pigment
situation when green and albino patches of ivy leaves were compared. Transmittance appeared inversely related to lamina thickness
in accordance with the Lambert Beer law. Significant correlations were found also between mesophyll water content and both
transmittance (positive) and reflectance (negative). Olive leaves showed peculiar optical patterns because of the dense and
continuous trichome layer on their abaxial surface.
Received: 3 January 1997 / Accepted: 5 May 1997 相似文献
12.
For the first time in Rome, house-dust mite infestation was studied in 90 randomly selected houses. In each house, mite infestation was assessed in three sites: mattress, bedroom and living room. In total, 87.8% of the sampled houses were positive for dust mites. In the houses infested, 11.4% showed densities of >100 mites/g of dust, 15.2% registered densities between 50 and 99, and in the remaining houses (73.4%), the densities were between 1 and 49 mites/g dust. The percentages of infested houses were positively correlated with the relative humidity (RH) values (r=0.89,P=0.02). At the lowest range of RH (between 46 and 50), the infestation was 50% and at the highest range of RH (between 73 and 78) it was 100%. The mattress was significantly the most infested (71.1%) of the tested sites. Only wool and spring mattresses were infested, and they did not show any significant differences in mite concentrations.Dermatophagoides farinae was the most abundant species (53.1%), followed byGlycyphagus domesticus (34.5%),D. pteronyssinus (5.2%), andEuroglyphus maynei (0.2%);D. farinae was also the most frequent species (56.9%). The remaining specimens (7.0%) were predator species commonly found in houses. The prevalence ofD. farinae in Rome is discussed. 相似文献
13.
M Grazia Tozzi U D'Arcangelo A Del Corso G W Ordal 《Biochimica et biophysica acta》1991,1080(2):160-164
A Ca(2+)-binding protein was identified in Bacillus subtilis in the log phase of growth. The molecular mass of this protein is about 38 kDa as estimated by polyacrylamide gel electrophoresis in the presence of SDS and by gel filtration. The protein was found to be resistant 10 min at 65 degrees C and was purified about 400 times, starting from heated crude extract, by conventional procedures. This novel protein is able to bind Ca2+ in the presence of an excess of MgCl2 and KCl both in solution and after SDS gel electrophoresis and electrotransfer. Since an impairment of the Ca2+ intake, in Bacillus subtilis, results in an impairment of chemotactic behavior (Matsushita, T. et al (1988) FEBS lett. 236, 437-440), 38 kDa protein may be involved in the regulation of chemotaxis. 相似文献
14.
Pozzolini M Sturla L Cerrano C Bavestrello G Camardella L Parodi AM Raheli F Benatti U Müller WE Giovine M 《Marine biotechnology (New York, N.Y.)》2004,6(6):594-603
In some sponges peculiar proteins called silicateins catalyze silica polymerization in ordered structures, and their study is of high interest for possible biotechnological applications in the nanostructure industry. In this work we describe the isolation and the molecular characterization of silicatein from spicules of Petrosia ficiformis, a common Mediterranean sponge, and the development of a cellular model (primmorphs) suitable for in vitro studies of silicatein gene regulation. The spicule of P. ficiformis contains an axial filament composed of 2 insoluble proteins, of 30 and 23 kDa. The 23-kDa protein was characterized, and the full-length cDNA was cloned. The putative amino acid sequence has high homology with previously described silicateins from other sponge species and also is very similar to cathepsins, a cystein protease family. Finally, P. ficiformis primmorphs express the silicatein gene, suggesting that they should be a good model for biosilicification studies. 相似文献
15.
Chandana Basu Mallick Florin Mircea Iliescu M?rt M?ls Sarah Hill Rakesh Tamang Gyaneshwer Chaubey Rie Goto Simon Y. W. Ho Irene Gallego Romero Federica Crivellaro Georgi Hudjashov Niraj Rai Mait Metspalu C. G. Nicholas Mascie-Taylor Ramasamy Pitchappan Lalji Singh Marta Mirazon-Lahr Kumarasamy Thangaraj Richard Villems Toomas Kivisild 《PLoS genetics》2013,9(11)
Skin pigmentation is one of the most variable phenotypic traits in humans. A non-synonymous substitution (rs1426654) in the third exon of SLC24A5 accounts for lighter skin in Europeans but not in East Asians. A previous genome-wide association study carried out in a heterogeneous sample of UK immigrants of South Asian descent suggested that this gene also contributes significantly to skin pigmentation variation among South Asians. In the present study, we have quantitatively assessed skin pigmentation for a largely homogeneous cohort of 1228 individuals from the Southern region of the Indian subcontinent. Our data confirm significant association of rs1426654 SNP with skin pigmentation, explaining about 27% of total phenotypic variation in the cohort studied. Our extensive survey of the polymorphism in 1573 individuals from 54 ethnic populations across the Indian subcontinent reveals wide presence of the derived-A allele, although the frequencies vary substantially among populations. We also show that the geospatial pattern of this allele is complex, but most importantly, reflects strong influence of language, geography and demographic history of the populations. Sequencing 11.74 kb of SLC24A5 in 95 individuals worldwide reveals that the rs1426654-A alleles in South Asian and West Eurasian populations are monophyletic and occur on the background of a common haplotype that is characterized by low genetic diversity. We date the coalescence of the light skin associated allele at 22–28 KYA. Both our sequence and genome-wide genotype data confirm that this gene has been a target for positive selection among Europeans. However, the latter also shows additional evidence of selection in populations of the Middle East, Central Asia, Pakistan and North India but not in South India. 相似文献
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17.
Abraham J. Koo Caitlin Thireault Starla Zemelis Arati N. Poudel Tong Zhang Naoki Kitaoka Federica Brandizzi Hideyuki Matsuura Gregg A. Howe 《The Journal of biological chemistry》2014,289(43):29728-29738
The plant hormone jasmonate (JA) controls diverse aspects of plant immunity, growth, and development. The amplitude and duration of JA responses are controlled in large part by the intracellular level of jasmonoyl-l-isoleucine (JA-Ile). In contrast to detailed knowledge of the JA-Ile biosynthetic pathway, little is known about enzymes involved in JA-Ile metabolism and turnover. Cytochromes P450 (CYP) 94B3 and 94C1 were recently shown to sequentially oxidize JA-Ile to hydroxy (12OH-JA-Ile) and dicarboxy (12COOH-JA-Ile) derivatives. Here, we report that a third member (CYP94B1) of the CYP94 family also participates in oxidative turnover of JA-Ile in Arabidopsis. In vitro studies showed that recombinant CYP94B1 converts JA-Ile to 12OH-JA-Ile and lesser amounts of 12COOH-JA-Ile. Consistent with this finding, metabolic and physiological characterization of CYP94B1 loss-of-function and overexpressing plants demonstrated that CYP94B1 and CYP94B3 coordinately govern the majority (>95%) of 12-hydroxylation of JA-Ile in wounded leaves. Analysis of CYP94-promoter-GUS reporter lines indicated that CYP94B1 and CYP94B3 serve unique and overlapping spatio-temporal roles in JA-Ile homeostasis. Subcellular localization studies showed that CYP94s involved in conversion of JA-Ile to 12COOH-JA-Ile reside on endoplasmic reticulum (ER). In vitro studies further showed that 12COOH-JA-Ile, unlike JA-Ile, fails to promote assembly of COI1-JAZ co-receptor complexes. The double loss-of-function mutant of CYP94B3 and ILL6, a JA-Ile amidohydrolase, displayed a JA profile consistent with the collaborative action of the oxidative and the hydrolytic pathways in JA-Ile turnover. Collectively, our results provide an integrated view of how multiple ER-localized CYP94 and JA amidohydrolase enzymes attenuate JA signaling during stress responses. 相似文献
18.
Maura Marinozzi Andrea Carotti Roccaldo Sardella Federica Buonerba Federica Ianni Benedetto Natalini Daniela Passeri Giovanni Rizzo Roberto Pellicciari 《Bioorganic & medicinal chemistry》2013,21(13):3780-3789
An asymmetric synthetic strategy was designed for the preparation of the four possible diastereoisomers of 3,6-dimethyl-1-(2-methylphenyl)-4-(4-phenoxyphenyl)-4,8-dihydro-1H-pyrazolo[3,4-e][1,4]thiazepin-7-one, a non-steroidal FXR agonist, we recently discovered following a virtual screening approach. The results obtained from an AlphaScreen assay clearly demonstrated that only the isomer endowed with 4R,6S absolute configuration is responsible for the biological activity. A deep investigation of the different putative binding modes adopted by these enantiomerically pure ligands using computational modeling studies confirmed the enantioselectivity of FXR towards this class of molecules. 相似文献
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