bluuebunny/crossref_metadata_2025_split huggingface dataset:
Properties of Ribulose Diphosphate Carboxylase/Oxygenase in the Tobacco
Authors: Okabe Keiichiro 
Published: August 2018

Abstract
Photorespiration, Ribulose 1,5-diphosphate-Carboxylase/Oxygenase, Gene Composition The activity of ribulose 1,5-diphosphate (RuDP)-carboxylase and RuDP-oxygenase was measured in crude leaf extracts of the tobacco (N . tabacu m) phenotypes which differed with respect to their gene constitution and with respect to their photosynthetic and photorespiratory activity. The green wild type (JWB) which carried the discussed two nuclear factors su and aur in the condition su/su Aur/Aur and su/su Aur/aur exhibits normal photosynthetic activity and low photorespiratory activity. A yellow-green chlorophyll-deficient phenotype (Su/su) carrying Su/su Aur/Aur has high photosynthetic activity on a chlorophyll basis but also high photorespiratory activity. A new yellow phenotype (Su/su var. Aurea) carrying both nuclear factors in a heterozygous condition Su/su Aur/aur has high photosynthetic activity on the basis of chlorophyll and low photorespiratory activity. The comparison of the RuDP-carboxylase/oxygenase activity in these three phenotypes shows that in the yellow-green phenotype Su/su the affinity of the RuDP-oxygenase towards oxygen is higher than in the green phenotype JWB and in the yellow phenotype Su/su var. Aurea. The Km ((O2) values for the RuDP-oxygenase activity are 890 /um for JWB, 630 μм for Su/su and 940 μм for Su/su var. Aurea and the corresponding Ki(CO2) values are 7.4 μм for JWB, 14.9 μм for Su/su and 5.8 μм for Su/su var. Aurea at pH 8.34. On the other hand, the affinity of the carboxylating activity of the enzyme towards CO2 shows no difference between JWB and Su/su var. Aurea, but a lower affinity in Su/su. This is expressed by the K m (C 02) values which are 107 μм for JWB, 143 μм for Su/su and 96 μм for Su/su var. Aurea at pH 7.8. However, the affinity of the oxygenase function of the enzyme towards RuDP seems to be unchanged in all three tobaccos and is found to be around Km (RuDP) 27 μм. From this result it appears that the nuclear factor su decreases in the condition Su/su Aur/Aur the affinity of the RuDP-carboxylase towards CO2 and increases the affinity of the RuDP-oxygenase towards oxygen. On the other hand, the factor aur seems to suppress this gene expression in the condition Su/su Aur/aur whereas both factors do not affect the binding of RuDP onto the enzyme.
Ability to Light-Induced Conductance Change of Arthropod Visual Cell Membrane, Indirectly Depending on Membrane Potential, during Depolarization by External Potassium or Ouabain
Authors: Stieve H. , Bruns M. , Gaube H. 
Published: August 2018

Abstract
Light responses (ReP) and pre-stimulus membrane potential (PM P) and conductance of photoreceptors of Astacus leptodactylus and Limulus polyphemus (lateral eye) were recorded and changes were observed when the photoreceptor was depolarized by the action of external ouabain or high potassium concentration application.
1 mм/1 ouabain application causes a transient increase of PMP and ReP in Limulus, followed by a decrease which is faster for the ReP (half time 34 min) than for the PMP (half time 80 min). Irreversible loss of excitability occurs when the PM P is still ca. 40% of the reference value.
In both preparations high external potassium concentration leads to total depolarization (beyond zero line to +10 - +20mV) of the PMP and after a time lag of 10 min also to a loss of excitability (intracellular recording). In extracellular recordings (Astacus) the excitability remains at a low level of 15%. The effects are reversible and are similar whether no or 10% external sodium is present. In all experiments the light-induced changes of membrane conductance are about parallel to those of the light response.
The fact that the ability of the photosensoric membrane to undergo light-induced conductance changes is membrane potential-dependent is discussed, leading to the explanation that dipolar membrane constituents such as channel forming molecules (probably not rhodopsin) have to be ordered by the m embrane potential to keep the membrane functional for the photosensoric action.
Thioacylamide und Thioacylharnstoffderivate als Inhibitoren des Photosystem II / Thioacylamides and Thioacylureas as Inhibitors of Photosystem II
Authors: Schenk Hainfried E. A. , Hanf Jürgen 
Published: August 2018

Abstract
Thioacylureas and thioacylam ides were found to inhibit photosynthetic O2-evolution (Hill-reactions) of “broken chloroplasts”, some derivatives approaching an I50 of 10-5м. The inhibition site is near photosystem II. The inhibitory effects of the tested derivatives vary in their pH-dependency between pH 5 and 8.
Immobilisierung von Cytidin und Uridin über 2'.3'-O-cyclische Acetalderivate an Agarose / Im mobilisation of Cytidine and Uridine via 2',3'-O-Cyclic Acetal Derivatives to Agarose
Authors: Seela Frank , Roseineyer Helmut 
Published: August 2018

Abstract
Condensation of cytidine or uridine with ethyl levulinate leads to the acetals 1a/2a. The reac­tion would be expected to give mixtures of diastereoisom ers. As shown by 1H and 13C NMR spectroscopy only one diastereoisomer is formed. By spectroscopic comparison of 1a/2a with the corresponding adenosine acetal the absolute configuration of the new chiral centre was found to be R. The acetal m ethyl group of 1a/2a in exo-location can serve to distinguish the two m ethyl signals of O-2′,3′-isopropylidenecytidine and -uridine in the NM R spectra. On alkaline hydrolysis of the esters the acids 1b and 2b are formed, which can be condensed through their carboxyl groups with 6-aminohexylagarose. The affinity resins 3 and 4 contain 7.1 μmol and 7.6 μmol ligand/g moist gel respectively. A biospecificity of the new polymers to cytidine-and uridine converting enzymes is expected.
Inhibition of Mg, Ca-ATPase from E. coli by Ruthenium Red
Authors: Scherr Franz , Günther Theodor 
Published: August 2018

Abstract
The membrane-bound, solubilized, and trypsin-treated forms of Mg, Ca-ATPase from E. coli are inhibited by ruthenium red[R R ]. The inhibition is noncompetitive and is reduced at higher sub strate concentrations. n-Butanol-extracted ATPase is not inhibited by ruthenium red and is not activated by KCl.
The Occurrence of Phenylalanine Ammonia-Lyase and Cinnamic Acid p-Hydroxylase on the Endoplasmic Reticulum of Cell Suspension Cultures of Glycine max
Authors: Postius C. , Kindi H. 
Published: August 2018

Abstract
1. The time course of activity of soluble and microsomal phenylalanine ammonia-lyase (PAL) was studied in dark grown cell cultures of soybean (Glycine max). A distinct activity increase of PAL in the soluble and microsomal fraction occurred prior to the stationary phase of the cell culture. Cinnamic acid p-hydroxylase and NADH : cytochrome c reductase, too, exhibited maximal activity in the log phase, 5 days after the transfer of soybean cells to fresh culture medium.
2. Upon subfractionation of the once washed microsomal fraction by sedimentation velocity centrifugation on a sucrose gradient, membranes of the endoplasmic reticulum could be separated from fractions containing mainly membranes from the Golgi apparatus or plasma membranes, respectively. PAL and cinnamic acid p-hydroxylase were found in fractions of endoplasmic reticulum whereas no activity of either enzymes could be detected in fractions containing Golgi apparatus or plasma membranes.
3. Repeated washing of microsomal fractions led to a residual membrane-bound PAL representing about 1% of the total PAL activity of the cells. This residual membrane-bound activity could be solubilized almost completely by Triton X-100 or digitonin at concentrations of 0.5 - 5%.
Association between the Doubling Time of Various Cells and Tissues, and the SH-Content of Their Soluble Proteins
Authors: Schauenstein E. , Gölles J. , Waltersdorfer H. , Sdiaur R. J. 
Published: August 2018

Abstract
The num ber of SH-groups of the soluble proteins (Prot-SH) of 12 different types of animal tum ors and of cultivated chicken fibroblasts increases with decreasing doubling tim e (td). Between Prot-SH and td an inverse association was found with a significance level of 99.5%.
After 30 min incubation in vitro, 4-hydroxypentenal (HPE) reacts with different am ounts of the Prot-SH of the investigated cells and tissues. It was found that the absolute, as well as the per­ cental amounts of HPE-reactive Prot-SH increase with decreasing td, each of the respective inverse associations was found to be highly significant. The tum ors were collected in three groups, each with a corresponding range of td and a mean value for Prot-SH . Taking the Prot-SH of the slowest growing tissue (DENA-hepatoma) as the reference value, the increments of Prot-SH were cal­ culated for each of the three groups and were found to be strikingly similar to the number of HPE-reactive Prot-SH. The single Prot-SH increm ents of the diverse cell and tissue types compared with DENA-hepatoma were found to be highly significantly and inversely associated with the respective Prot-SH decreases caused by HPE.
Hence it may be concluded that HPE reacts preferably with those of the Prot-SH which are of some functional importance for tum or growth and, moreover that the attack on those thiols is the more effective the faster the tumor is growing.
Uptake of Polynucleotides by Mammalian Cells XV. Properties and Function of a DNA-Protein Complex Situated in the Outer Membrane of Ehrlich Ascites Tumor Cells
Authors: Schell P. L. 
Published: August 2018

Abstract
1) DNA-protein complexes are supposed to be original constituents of the membrane of Ehrlich ascites tum or cells. These complexes can be attacked at the surface of viable cells by DNase or protease. The DNA is partially embedded in protein structures.
2) The net charge of this complex is of major importance for the RNA uptake capacity of the cells. Negatively charged DNA which is situated at the surface hinders RNA uptake. This is the explanation for the stimulation of RNA uptake by DNase or the decrease in RNA uptake after protease treatment.
3) Upon treatment of DNA-dcficient complexes with homologous or heterologous DNA the original RNA uptake capacity of the cells is restored but the original conformation of the complex cannot be regained.
4) The DNase action on the complex is tem perature dependent in a sigmoidal fashion. It is m arkedly slowed down at tem peratures below 12 °C. This implies that structural dianges in the complex occur at this transition tem perature which make surface DNA susceptible to DNase. This effect can only be observed in original structures but not in reconstituted ones.
5) Polyanion treatment of the cells [poly (L-lysine) ] which increases their RNA uptake capacity, most probably does not interact with the DNA-protein complex. Poly (L-lysine) appears to act at other m em brane sites.
6) The DNA-protein complex has been investigated entirely in situ , i. e. situated in the membrane of viable cells.
Zur Photosynthese grüner Pflanzen, VIII [1]: in vitro-Sauerstoffaustausch zwischen Carotinoid-Epoxiden und Wasser? / Photosynthesis of Green Plants, V III: in vitro Oxygen Exchange between Carotenoid Epoxides and Water? 1
Authors: Johannes B. , Budzikiewicz H. 
Published: August 2018

Abstract
The in vitro exchange between the epoxide oxygen of carotenoids and that of water reported in literature could not be verified. Our observations rather suggest that oxidation products of the labile polyene system may invalidate 18O enrichment data obtained by indirect analysis.
Properties of Single Cells in Posterior Lateral Eyes of Jumping Spiders
Authors: Hardie R. C. , Duelli P. 
Published: August 2018

Abstract
Properties of single cells in the posterior lateral (PL) eyes of the jum ping spider Plexippus validus are described. Only one spectral class of cells was encountered and the spectra sensitivity was indistinguishable from that measured from the ERG , both peaking at ca. 535 nm. Angular sensi­ tivity (width of angular sensitivity function at the 50% level) averaged .89° ± .12°, the smallest value being .77°. Absolute sensitivity (reciprocal of the number of quanta of peak wavelength, on axis required to generate a 50% response) averaged 1.43 + 2 .5 X 1 0 -11 q-1 ,cm2·s. A ll cells studied were sensitive to the plane of polarised light. The per­ formance of receptors in the PL eyes is compared with that of receptors in the compound eyes of diurnal insects. It is concluded that the single lens eye system of spiders is in ­ herently superior in design to the insect compound eye.
Characterization, Development and Localization of "Flavanone Synthase" in Tulip Anthers
Authors: Siitfeld R. , Kehrel B. , Wiermann R. 
Published: August 2018

1. “Flavanone synthase” was isolated from anthers of Tulipa cv. “Apeldoorn” and partially purified by (NH4) 2SO4 fractionation, gel chromatography and isoelectric focussing. The enzyme preparation was free of chalcone-flavanone isomerase activity.
2. p-Coumaroyl-CoA, caffeoyl-CoA and feruloyl-CoA were found to be efficient substrates of the synthase. The products formed were naringenin (5,7,4′-trihydroxyflavanone), eriodictyol (5,7,3′,4′-tetrahydroxyflavanone) and homoeriodictyol (5,7,4′-trihydroxy-3′-methoxyflavanone), respectively. Addition of thiol reagents at concentrations exceeding 10-3 м caused inhibition of the enzyme. “ Release products” , however, were not detectable. Although exclusively chalcones accumulate in the tulip anther, only flavanones but no chalcones were detectable in our in vitro system.
3. The apparent Km values for p-coumaroyl-CoA, caffeoyl-CoA and feruloyl-CoA were 1 .7× 10-6 м, 1.6× 10-6 м and 2 .5 ×10-6 м, respectively. Similar data were observed for malonyl- CoA.
4. No cofactors are required for the synthase reaction. The enzyme is strongly inhibited by the reaction products flavanone and coenzyme A . Maximum enzyme activity was found at pH 8.0 and 30 °. The molecular weight was approx. 55,000.
5. Synthase activity develops in early postmeiotic stages of microsporogenesis. Highest specific activities of the enzyme coincide with a maximum in chalcone accumulation within the anthers.
6. The contents of anthers was separated into two fractions, pollen and tapetum. Highest specific activities were observed with tapetum fractions, while pollen fractions exhibited only very low activities. The high enzyme activity in the tapetum fraction points to the important role of the tapetum in the biosynthesis of flavonoids in the loculus of anthers.
Structural Aspects of Histone Complexes and Nucleosomes Revealed by the Accessibility of Cysteine Side Chains
Authors: Bode Jürgen , Standt Ulrich-Dieter 
Published: August 2018

Abstract
Chemical modification with 5,5′-dithiobis-(2-nitrobenzoic acid) shows that histone H3 cysteines 110 (chicken) or 96 and 110 (calf) are completely protected in native chromatin and core particles but become unmasked simultaneously during a salt induced dissociation. In whole histone extracted from chicken erythrocyte chromatin, H3 Cys-110 residues experience a uniform environ­ment at 2 м NaCl and pH 5.5. In whole histone extracted under the same conditions from calf thymus, H3 Cys-96 provides a more accessible thiol group than Cys-110. At higher pH values a conformational heterogeneity is induced causing a partial exposure of both cysteine side chains. The kinetic approach described in the present work provides a highly sensitive means to probe the homogeneity of H3 containing protein complexes
Uracil Catabolism by Escherichia coli K12S
Authors: Šimaga Š. , Kos E. 
Published: August 2018

Abstract
Experiments designed to elucidate the mechanism of uracil degradation by E. coli K12S showed that in contrast to uracil, dihydrouracil - the postulated intermediate of a reductive mechanism - did not stimulate the growth of bacteria as additional source of nitrogen, nor it was catabolized to ureido carbon dioxide. However, the chromatographic analysis of dihydrouracil metabolic products, re­vealed the presence of an enzyme converting dihydrouracil to β-ureidopropionic acid. Results of growth and biochemi­ cal studies indicated that barbituric acid - the postulated intermediate of an oxidative pathway - is not involved in uracil degradation.
Analysis of Different Mechanisms of Photosynthetic Oxygen Reduction
Authors: Elstner E. F. , Frommeyer D. 
Published: August 2018

Three mechanisms of oxygen reduction by chloroplast lamellae in the presence of autoxidizable electron acceptors can be differentiated by product analyis in the presence or absence of either dibromothymoquinone (DBMIB) or superoxide dismutase (SOD) :
1)H2O2 is the product of two-electron oxygen reduction by 2,3-dimethyl-5,6-methylencdioxy-p- benzoquinone, involving only photosystem II. This reaction is not inhibited bv either DBMIB or SOD.
2)Superoxide anion, and H2O2 as the product of its dismutation, are products of monovalent oxygen reduction following autoxidation of certain low potential electron acceptors (herbicides) of photosystem I. These reactions are not inhibited by SOD but are blocked by DBMIB.
3)H2O2 is the product of and “apparent” two-electron photoreduction of oxygen, mediated by certain o-diphenols (caffeic acid). These reactions are inhibited by both DBMIB and SOD in­dicating the involvement of photosystem I and of O2- as an intermediate in the H2O2 producing reaction.
Über den Gehalt an membrangebundenen und freien Ribosomen in Saccharomyceszellen nach Hemmung der Proteinsynthese mit Cycloheximid / The Content of Membrane-Bound and Free Ribosomes in Saccharomyces after the Inhibition of Protein Synthesis with Cycloheximid
Authors: Kraft-Creech Joan , Pietsch Ingrid , Lochmann Ernst-Randolf 
Published: August 2018

Abstract
After the inhibition of protein synthesis in Saccharomyces cells with cycloheximid, the content of membrane-bound ribosomes decreases significantly, whereas the content of free ribosomes remains the same as the untreated control for a longer period of time. This is further evidence that in yeast cells protein synthesis takes place only on membrane-bound ribosomes.
Anthocyanins Isolated from Petals of Various Genotypes of the Red Campion (Silene dioica (L.) Clairv.)
Authors: Kamsteeg John , Brederode Jan van , Küppers Frans J. E. M. , Nigtevecht Gerrit van 
Published: August 2018

Abstract
Anthocyanin pigments present in petals of various genotypes of Silene dioica were identified by RF-values, UV-spectra, partial and total hydrolysis, alkalysis, NMR-and IR-spectra. Both the 3-glucosides, 3,5-diglucosides, 3-rutinosides and 3-rutinosides-5-glucosides of cyanidin and pelargonidin were found.
The location of the acyl group at the 3-O-bound sugar in acylated anthocyanins - p-coumaric acid in pelargonidin-glycosides and caffeic acid in cyanidin-glycosides - has been determined by partial hydrolysis, peroxide oxidation, and oxidative cleavage with sodium periodate followed by reduction with sodium borohydride and identification of the polyalcohols formed after hydrolysis. The phenolic acids have been shown to be attached to the 4-hydroxyl group of rhamnose in anthocyanidin 3-rhamnosylglucosides and to the 6-hydroxyl group of the 3-O -bound glucose in anthocyanidin 3-O-glucosides.
Correlation between Photosynthesis and Plant Lipid Composition
Authors: Heise K.-P. , Harnischfeger G. 
Published: August 2018

Abstract
An attempt is reported to link changes in thylakoid lipid composition with the electron-transport and ATP-formation capability of the chloroplast. The observation that the monogalactolipid : phosphatid-ratio (MGDG/PL) of leaf sections shows a linear correlation with the P/2e value of simultaneously isolated Jensen-Bassham plastids was followed up experimentally for an in vitro plastid system. Lipid composition in these experiments was changed by illuminating the suspension with white light. The result shows, that similar dependencies can be obtained with both Jensen-Bassham chloroplasts and, up to a certain degree, chloroplast membrane fragments.
Isolation of Kaempferol-3-O-rhamnoglucoside, a Flavonoid Glycoside from Zephyranthes Candida
Authors: Nakayama Mitsuru , Horie Tokunaru , Tsukayama Masao , Masumura Mitsuo , Hayashi Shüichi 
Published: August 2018

Abstract
Kaempferol-3-O-rhamnoglucoside, a flavonoid glycoside, was isolated from fresh withe petals of Zephyranthes candida.
Isolation of Single Stranded DNA from Purified Hepatitis A-Virus
Authors: Flehmig Bertram , Royer Hans Dieter , Gerth Hans-Joachim 
Published: August 2018

Abstract
Hepatitis A-Yirus-Single-Sranded D N A , Electron Microscopy, Length Measurements, Parvovirus Hepatitis A-virus was purified from human stools by three purification steps. Virus was identified by radioimmuno-assay and purity monitored with immune electron microscopy. Virus particles, serologically and morphologically identical, banded in CsCl in two density ranges at 1.31 — 1.34 g/cm3 and at 1.41 — 1.43 g/cm3. Virions of density 1.31 — 1.34 g/cm3 were shown to contain single-stranded D N A of different size classes. Class I 1.33 kb, class I I 4.61 kb in addition a small amount of molecules was de­ tected with lengths up to 15 kb.
Responses of Barnacle Photoreceptors to High Energy Flashes of Short Duration
Authors: Krischer Christof C. , Dahl R. D. , Körfer M. 
Published: August 2018

Abstract
In chromatic adapted barnacle median and lateral photo­receptors the two stable states of the photopigment (rhodopsin R and metarhodopsin M) were interconverted with intense, colored light flashes of 1 ms duration. Only after conversion of the red adapted photoreceptor in K+-Ringer solution with an intense flash the negative early receptor potential, ERP (of R) gradually appeared detected with an indicator flash. For the opposite conversion (blue adapted, R→M) the gradual appearence of the positive ERP (M) was not measurable in the same time span. In artificial seawater all flash stimuli yielded - irrespective of color - the transient component of the late receptor potential (LRP). ERP results for the lateral photoreceptor are dis­cussed in view of an existing kinetic model and an attempt is made to give an explanation which covers the new LRP transient and ERP results for both types of photoreceptor (appendix).
Schwermetalle in höheren Pilzen, IV * Silber / Heavy Metals in Higher Fungi, IV Silver
Authors: Schmitt Johannes A. , Meisch Hans-Ulrich , Reinle Wolfgang 
Published: August 2018

Abstract
In several series of 581 samples, Higher Fungi, especially from the Boletales and Gasteromy­cetes, were analyzed by atomic absorption spectroscopy on their content of the trace metal silver. The highest Ag-content was found in the Lycoperdales (max. 50 mg/kg dry matter) and in some species of the genus Boletus (max. 15 mg Ag/kg). The other fungi tested showed a mean silver content of 1 mg/kg or lower. The species with the highest amounts of the trace metal were found to enrich silver 300 fold compared to the substrate.
Mixed Substrates: trans-and cis -[1-14C]Monounsaturated Fatty Acids with a Fairly Uniform Distribution of Positional Isomers
Authors: Richter Ingolf , Mukherjee Kumar D. , Weber Nikolaus 
Published: August 2018

Abstract
Simple methods are described for the preparation of trans-[1-14C]monounsaturated fatty acids and cis -[1-14C]monounsaturated fatty acids, each with a fairly uniform distribution of positional isomers, which can serve as mixed substrates in biochemical studies. Methyl trans- [1-14C] octadecenoates and methyl trans-[1-14C] eicosenoates are prepared by partial catalytic hydrogenation of methyl [1-14C] linolenate and methyl [1-14C] arachidonate, respectively, follow ed by argentation chromatography of the partially hydrogenated products. Methyl trans-[1-14C] octadecenoates and methyl trans-[1-14C] eicosenoates, thus obtained, yield the corresponding methyl cis-[1-14C] octadecenoates and methyl cis-[1-14C] eicosenoates, respectively, after trans-cis equilibration and argentation chromatography. Hydrolysis of each of these methyl esters yields the fatty acids.