Invertase in Immobilized Cells of Eschscholtzia Californica

Cell suspension culture of Eschscholtzia californica Cham. were permeabilized by Tween 20 or 80, and immobilized by glutaraldehyde. The highest invertase activity was at pH 4.5 and temperature 50 °C. The hydrolysis of the substrate was linear for 5 h reaching 60 % conversion. The cells had high invertase activity and a good stability, and in long-term storage they showed convenient physico-mechanical properties.     

Characterization of a meta-Fluorotyrosine-Tolerant Cell Culture of Eschscholtzia californica Cham

A cell line of Eschscholtzia californica selected for meta-fluorotyrosine (MFT) tolerance was found to have 10-fold increased levels of phenylalanine and tyrosine compared to the parent line, while most other amino acids were only increased 2-fold. Tracer experiments with shikimic acid in the presence of MFT showed that the biosynthesis of the aromatic amino acids was not impaired in the tolerant line. Feeding experiments with phenylalanine, tyrosine, or shikimic acid also revealed a reduced turnover of the pools of the aromatic amino acids in the variant. Thus undisturbed de novo biosynthesis of the aromatic amino acids and dilution of toxic effects of MFT by the enlarged pool sizes seemed to be the main reason for the acquired tolerance. Despite the enlarged availability of the precursor tyrosine, formation of the benzophenanthridine alkaloids was enhanced neither in the growth nor in the production medium.     

Effects of gibberellic acid and cyclic 3',5'-adenosine monophosphate on the flowering of Eschscholtzia californica Cham., a qualitative long day plant.

GA₃ and cyclic AMP induce floral buds in Eschscholtzia californicaunder noninductive short days and hasten it under inductivelong day conditions. (Received June 8, 1976; )     

Elicitation of benzophenanthridine alkaloid synthesis in Eschscholtzia cell cultures

Quaternary benzophenanthridine alkaloids (sanguinarine, chelerythrine, chelirubine, chelilutine and macarpine) are specifically induced by cell wall components of Penicillium and Saccharomyces in a colorless strain of Eschscholtzia californica cell suspension cultures. Classical elicitors such as the Phytophthora megasperma elicitor are inactive. The alkaloid synthesis is, however, strongly induced by certain polypeptide antibiotics. Out of 190 tested plant species the yeast elicitor provoked benzophenanthridine synthesis in 13 cultures. One of the branch point enzymes, namely the berberine bridge enzyme, catalysing the formation of (S)-scoulerine from (S)-reticuline, is strongly stimulated during the elicitation process. These results clearly demonstrate the induction of the benzophenanthridine biosynthetic pathway by microbial elicitors.Abbreviations ACC 1-Aminocyclopropane-1-carbonic acid - EDTA Ethylenediaminetetraacetic acid - LS-medium Linsmaier and Skoog medium - Pmg Phytophthora megasperma     

A study of statistical error in isothermal titration calorimetry

In isothermal titration calorimetry (ITC), the two main sources of random (statistical) error are associated with the extraction of the heat q from the measured temperature changes and with the delivery of metered volumes of titrant. The former leads to uncertainty that is approximately constant and the latter to uncertainty that is proportional to q. The role of these errors in the analysis of ITC data by nonlinear least squares is examined for the case of 1:1 binding, M+X right arrow over left arrow MX. The standard errors in the key parameters-the equilibrium constant Ko and the enthalpy DeltaHo-are assessed from the variance-covariance matrix computed for exactly fitting data. Monte Carlo calculations confirm that these "exact" estimates will normally suffice and show further that neglect of weights in the nonlinear fitting can result in significant loss of efficiency. The effects of the titrant volume error are strongly dependent on assumptions about the nature of this error: If it is random in the integral volume instead of the differential volume, correlated least-squares is required for proper analysis, and the parameter standard errors decrease with increasing number of titration steps rather than increase.     

A new variety of coreopsis Californica (Compositae) Endemic to Arizona

Coreopsis californica var. newberryi, a new variety, differing from typical material ofC. californica in achene morphology, is proposed. Achene spotting in the two varieties exhibits maternal inheritance.     

珍稀濒危植物沙冬青花生物学研究

沙冬青蝶形花冠,柱头具指状突起,分长柱头和短柱头。群落花期约47 d,单花花期约7 d,分为露黄、微开、盛开、凋谢4个时期。TTC法测定4个时期花粉均具活力,可保持70 d左右,苯胺蓝测定柱头可受性3~4 d。沙冬青花一般在开花前一天就开始泌蜜,开花第2~3 d,分泌量达到高峰,花后4~5 d产蜜量减少直至停止,日泌蜜和散粉集中在10:00-14:00。沙冬青开花受环境的影响。     

A statistical model for the study of self-fertilization in plants

A model is proposed for the study of plant breeding where the self-fertilization rate is of importance. The model can be used to provide convenient maximum likelihood estimation of the self-fertilization rate and allelic frequencies in a parental population and its pollen pool. The self-fertilization rate can also be allowed to vary with genotype or other characteristics of a plant. A simple example illustrates the methodology.     

Elicitation of sanguinarine production in two-phase cultures of Eschscholtzia californica

Large increases in sanguinarine production were observed in suspension cultured Eschscholtzia californica cells treated with elicitors prepared from yeast extract, Colletotrichum lindemuthianum and Verticillum dahliae. Compounded silicone fluid, an ideal accumulation phase for the two-phase culture of E. californica, accumulated a large amount of sanguinarine produced in a specific manner and increased sanguinarine production. Elicitation in combination with two-phase culture additionally increased net sanguinarine production, as well as the sanguinarine concentration in the accumulation phase.     

A phenological study of flowering period and flower colours of aromatic plants in Greece

The flowering period and flower colour spectrum of 170 aromatic plant species are studied in 18 representative regions in Greece. The duration of the early to late flowering of the species is recorded for each region and for Greece as a whole. The basic flower colours (green, yellow, red and violet) are defined and the colour spectra for each region and for the whole country are given by converting absolute to relative values. The Sørensen similarity coefficient is applied to compare regions and the relationship among them as well as with a control region (Athos peninsula). Conclusions are drawn as to the time of maximum flowering and the decrease in the proportion of flowering species from north to south. In addition, interpretations are given for the symmetrical flowering curve of Greece as a whole, compared to the skewed curves of the islands.Nomenclature follows T. G. Tutin et al. (eds.) 1964–1980. Flora Europaea 1-5, Cambridge.     

A multidimensional statistical study of similarities between 74 notes used in perfumery

From a data bank of 2467 odoriferous products, the similaritiesbetween 74 notes used in perfumery were calculated. The similaritymatrix (74,74) contains – 63% of zero values and showsthat only a few pairs of notes present high similarity coefficients.A fine analysis using ascending hierarchical taxonomy with thecomplete linkage procedure shows that 14 notes are isolatedwhile 60 notes are regrouped in 27 groups containing two tofour notes. The isolated notes correspond to well-defined structuralparticularities. Some pairs of notes or groups present similaritiesin their chemical structures but some groups are built on thebasis of semantic processes. This study shows that the notesare generally independent, with no strict hierarchy among them,and rules out the existence of primary odors.     

A statistical study of the interspike-interval distribution of cortical neurons]

Spontaneous activity was recorded extracellularly by glass microelectrodes from 54 neurons of the Gyrus sigmoideus posterior of unnarcotized and gallamine-immobilazed cats, and the sequential and nonsequential interspike-interval histograms were determined using the multi-channel analyzer CAT 400 C. The interval distributions were characterized by graphic criteria, and it was attempted to describe these distributions mathematically by four biparametric distributions, the Weibull, lognormal, gamma and normal distributions. 80% of the frequency distributions of type I (exponential), II (left skew, gamma-similar) and IV (almost symmetrical) could be assigned to these distributions, namely 43% of the lognormal distribution, 32% of the Weibull distribution, and 5% of the gamma distribution. The interval histograms of the type III (left skew, steep) and V (bimodal) could not be described by any of the distributions selected.     

A morphometric study on the effects of ethylene treatment in promoting abscission of tobacco flower pedicels

The ultrastructural changes observed in ethylene-induced abscission of tobacco flower pedicels (Nicotiana tabacum L. `Little Turkish') were studied by the techniques of morphometric analysis. The surface area of the membranes, relative volume of the organelles, and the number of organelles were determined for both ethylene-treated and control cells. In pedicels exposed to ethylene for 4.5 to 5 hours, abscission was evident within the separation zone. The most significant change in cell structure was observed in the surface area of the rough endoplasmic reticulum which more than doubled with ethylene treatment of the tissue.     

A statistical mechanical study of helix-coil transition in concentrated solutions of polypeptides and proteins

The helix–coil transition in polypeptides was studied by methods of statistical mechanics, taking account of interaction between “melted” amide groups through hydrogen bonds. The statistical sums are calculated in the explicit form for two limit cases: (1) the dilute solution when the main contribution is given by collisions of two particles; (2) “condensation” when contacting macromolecules form a united aggregate. In the first case the transition enthalpy was shown to decrease linearly when the concentration increases, while at the appropriate choice of theoretical parameters, melting temperature and range are almost independent of the concentration. In the second case the structural transition parameters were shown to be independent of the concentration (the saturation effect). These results agree with the experimental data on synthetic polypeptides reported by other authors and with data on some globular proteins (serum and egg albumin) reported in this paper.     

A multivariate statistical study of skull measurements of five taxa of gazelles

A multivariate analysis using canonical variates and the D² test show that five taxa of Palaearctic gazelles examined are distinct. Several forms of gazelles of dubious taxonomic position were also compared on the canonical axes, with conclusions not dissimilar to those of recent workers on the Arabian gazelles, viz. that there are three distinct species in the Arabian peninsula; Gazella dorcas saudiya, Gazella gazella arabica and Gazella subgutturosa marica. Gazella dorcas populations in Somalia have a local form in G. dorcas pelzelni distinct in horns but not in skull measurements from Gazella spekei in the nearby highlands.