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31.
Antonella Angiolillo Fausto Panara Gina Piccinini Gian Luigi Gianfranceschi 《Molecular biology reports》1991,15(1):39-43
A protein kinase, type NII, has been purified from wheat germ chromatin. The enzyme, which uses both ATP and GTP as phosphoryl donors, catalyzes the phosphorylation of casein, phosvitin and E. coli RNA polymerase, but not of histone proteins. Polypeptide bands at 46 kDa, 37 kDa and 25 kDa were estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Autophosphorylation of the 25 kDa subunit was observed following incubation of the purified kinase with (-32P)ATP and (-32P)GTP. 相似文献
32.
J. E. Baker 《Entomologia Experimentalis et Applicata》1988,46(1):47-54
Rank transformation of specific activity values of -amylase across four strains of Sitophilus oryzae (L.) and four strains of S. zeamais Motschulsky indicates that levels of these predominant enzymes are highest in adults feeding on hulled barley or long-grain brown rice. Intermediate activity levels are found in weevils feeding on yellow corn (maize) and lowest levels are found in wheat-fed weevils. Although extracts prepared from barley contain inhibitory activity against two purified isoamylases from S. oryzae, levels of the naturally-occurring -amylase inhibitors against these two enzymes are about 2.2-fold and 6.1-fold, respectively, more concentrated in wheat. Ingestion of these amylase inhibitors and formation of an inactive enzyme:inhibitor complex with previously secreted amylase may account for the lower activity of amylase in weevils of both species feeding on wheat. Amylase levels across all strains feeding on a given diet are about 2-fold higher in S. oryzae than in S. zeamais. Significant differences in activity levels were also found between strains in both species. Since -amylase is a predominant digestive hydrolase in these species, the degree to which cereal diets affect amylase levels may indicate their suitability as potential hosts.
Résumé La transformation de rang des valeur d'activité spécifique de l'-amylase de 4 souches de S. oryzae et de 4 souches de S. zeamais montre que les niveaux les plus élevés de ces enzymes prédominantes s'observent chez les adultes nourris d'orge mondé ou de riz brun á grains longs. Des niveaux intermédiaires d'activité ont été obtenus chez les insectes élevés sur maïs jaune, et les niveaux les plus faibles chez ceux élevés sur blé. Bien que les extraits préparés à partir d'orge présentent une activité inhibitrice de deux isoamylases purifiées de S. oryzae, les niveaux des inhibiteurs naturels -amylase de ces deux enzymes sont environ respectivement 2,2 et 6,1 fois plus concentrés dans le blé. L'ingestion de ces inhibiteurs d'amylase et la formation d'un complexe enzyme inactive/inhibiteur avec l'amylase secrétée antérieurement, peut rendre compte de la plus faible activité de l'amylase chez les charançons consommant du blé. Le niveau d'amylase de S. oryzae est 2 fois plus élevé que celui de S. zeamais pour toutes les souches élevées sur un régime donné. Des niveaux d'activité significativement différents ont été trouvés suivant les souches pour chacune des deux espèces. Puisque l'amylase est la principale hydrolase digestive de ces espèces, l'intensité de la modification des teneurs en amylase par la consommation de céréales peut indiquer leur adéquation comme hôtes potentiels.相似文献
33.
Mottling phenomena and quality of grains of different genotypes of Durum wheat grown under limited irrigation conditions 总被引:1,自引:0,他引:1
Summary Field experiment was conducted to show the effect of one irrigation of 10 cm water applied to durum wheat (Triticum durum) at crown root initiation stage, active tillering stage, anthesis stage and compared them with non irrigated plot using A-206, A-28, A-1-8-8-42-1, G.W.-1 and A-23-10 genotypes under the conditions of salt affected areas having shallow saline aquifer, on quality, yield and mottling phenomena in wheat grain. Application of irrigation significantly increased the yield and decreased the per cent mottled grain and the maximum achievement was obtained when water was applied during the stage of anthesis. Non mottled grain contained higher protein than mottled grain and there were no considerable differences in other biochemical constituents. Genotype G.W.-1 stands first in its yield performance and low mottled grain. 相似文献
34.
G. Galili M. Feldman 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,69(5-6):583-589
Summary Total endosperm proteins extracted from both several common wheat cultivars and some intervarietal substitution lines derived from them were fractionated according to their molecular weight in a high resolution one-dimensional gel electrophoresis. The four donor cultivars and the recipient one — Chinese Spring, possessed differentially migrating protein bands in the fractions of high molecular weight (HMW) glutenins and gliadins. Several of these bands were identified for the first time in this study. By utilizing intervarietal substitution lines the control of the HMW glutenins and gliadins by chromosomes of homoeologous group 1 was either reaffirmed or, for the new bands, established. Several HMW gliadin subunits showed a considerable variation in their staining intensity in the intervarietal substitution lines indicating that their expression was dependent on the genetic background.This paper is based on a portion of a dissertation to be submitted by G. Galili in partial fulfilment of the Ph.D. requirements of the Feinberg Graduate School, The Weizmann Institute of Science, RehovotThe Marshall and Edith Korshak Professor of Plant Cytogenetics 相似文献
35.
Abstract. Chlorophyll fluorescence emission spectra and the kinetics of 685 mm fluorescence emission from wheat leaf tissue and thylakoids isolated from such tissue were examined as a function of excitation wavelength. A considerable enhancement of fluorescence emission above 700 nm relative to that at 685 nm was observed from leaf tissue when it was excited with 550 nm rather than 450 nm radiation. Such excitation wavelength dependent changes in the emission spectrum occurred over an excitation spectral range of 440–660 nm and appeared to be directly related to the total quantity of radiation absorbed at a given excitation wavelength. Experiments with isolated thylakoid preparations demonstrated that changes in the fluorescence emission spectrum of the leaf were attributable to the optical properties of the leaf and were not due to the intrinsic characteristies of the thylakoid photochemical apparatus. This was not the case for the observed excitation wavelength dependent changes in the 685 nm fluorescence induction curve obtained from leaf tissue infiltrated with DCMU. Excitation wavelength dependent changes in the ratio of the variable to maximal fluorescence emission and the shape of the variable fluorescence induction were observed for leaf tissue. Isolated thylakoid studies showed that such changes in the leaf fluorescence kinetics were representative of the way in which the photochemical apparatus in vivo was processing the absorbed radiation at the different excitation wavelengths. The results are considered in the context of the use of fluorescence emission characteristics of leaves as non-destructive probes of the photochemical apparatus in vivo. 相似文献
36.
P Midoux J P Grivet F Delmotte M Monsigny 《Biochemical and biophysical research communications》1984,119(2):603-611
The synthesis of N-acetyl- and N-trifluoroacetyl-glucosaminides was reported. The interaction of these compounds with wheat germ agglutinin, a plant lectin specific for N-acetyl-glucosamine and sialic acid, was investigated by two complementary approaches: 1H and 19F NMR, and fluorescence spectroscopy. This last technique relies on the existence of a competitive equilibrium involving the protein, the ligand and O-(methylumbelliferyl)-N-acetyl-glucosaminide, a fluorescent saccharide. The binding constants and the chemical shifts in the complex were determined and were related to the protein structure. 相似文献
37.
Structural comparison of the two distinct sugar binding sites in wheat germ agglutinin isolectin II 总被引:12,自引:0,他引:12
C S Wright 《Journal of molecular biology》1984,178(1):91-104
38.
接触二氧化硫后小麦叶片中逆境乙烯的生物合成 总被引:2,自引:0,他引:2
AVG和AOA强烈抑制二氧化硫处理小麦叶片中乙烯产生和ACC合成,对MACC的形成也有一定的抑制作用。CoGl_2明显抑制乙烯产生,而ACC大量积累,MACC含量则未因ACC增加而相应增加。DNP和CCCP也抑制乙烯产生,但前者引起ACC大量积累,后者引起ACC含量下降。CHI对乙烯产生和ACC形成均显示强烈的抑制作用,同时也明显抑制MACC形成。这表明小麦叶片接触SO_2引起的逆境乙烯也是循蛋氨酸→SAM→ACC→乙烯途径。 相似文献
39.
A. N. WEBBER N. R. BAKER CANDIDA D. PAIGE M. F. HIPKINS 《Plant, cell & environment》1986,9(3):203-208
Abstract Photosynthetic electron transport activities and the ability to generate and maintain a trans-thylakoid proton electrochemical gradient were examined during chloroplast development in 4-day-old wheat leaves grown under a diurnal light regime. Polarographic and spectropholometric studies on leaf tissue demonstrated that poorly developed chloroplasls at the leaf base could photo-oxidize water and transfer electrons from photosystem 2 to photosystem 1. The capacity for non-cyclic whole-chain electron transport increased during chloroplast development. Thylakoids isolated from the leaf base, although capable of pumping protons into the inlrathylakoid space, could not maintain a trans-membrane proton electrochemical gradient; this ability developed at later stages of chloroplast biogenesis in the leaf. The implications of these results for the energetics of the developing leaf are discussed. 相似文献
40.
Localization of wheat-germ agglutinin in developing wheat embryos and those cultured in abscisic acid 总被引:1,自引:0,他引:1
The time course of appearance of wheat-germ agglutinin (WGA) in the various embryonic tissues during embryogenesis in Triticum aestivum L. was studied by sensitive immunofluorescence and peroxidase-antiperoxidase detection systems. The radicle, root cap and coleorhiza first accumulated WGA in early Stage II (8-10 d post-anthesis) prior to the main period of embryo growth, while WGA was found in the epiblast and coleoptile in early and late State III, respectively. Stage III is characterized by maximum embryo growth, followed by desiccation which occurs in Stage IV. When Stage-II embryos were precociously germinated in the absence of abscisic acid (ABA) no WGA was detected in the coleoptile and epiblast of the young seedlings. In the presence of ABA, Stage-II embryos did not germinate but WGA precociously accumulated in the coleoptile and epiblast. The levels and distribution of WGA in the resulting embryo resembled those in a fully mature, dry embryo (Stage V). Barley possesses a seed lectin similar to WGA, but it is never detected in coleoptiles. Some but not all of the barley cultivars tested were found to accumulate lectin in this organ of mature embryos when treated with ABA. Thus, ABA appears to be involved in the highly regulated temporal and spatial expression of WGA during embryogenesis in cereals.Abbreviations ABA
abscisic acid
- DIC
differential interference contrast
- PAP
peroxidase-antiperoxidase
- WGA
wheat-germ agglutinin 相似文献