bluuebunny/crossref_metadata_2025 huggingface dataset:
Separation of the S-Adenosylmethionine: 5-and 8-Hydroxyfuranocoumarin O-Methyltransferases of Ruta graveolens L. by General Ligand Affinity Chromatography
Authors: Sharma Satish K. , Garrett Jinnie M. , Brown Stewart A.
Published: August 2018

Two S-adenosyl-ʟ-methionine:furanocoumarin O-methyltransferases of R . graveolens, acting at the 5-and 8-hydroxyls of the psoralen nucleus, were completely resolved by adsorption on a general affinity ligand, 5 -(3-carboxypropanamido) xanthotoxin, followed by specific desorption by bergaptol and xanthotoxol, respectively. The 5-O-methyltransferase was purified 450-fold by this procedure, the 8-O-methyltransferase 112-fold, and both enzyme fractions were electrophoretically homogeneous. No resolution could be achieved of the activity against two 5-hydroxypsoralens or of the activity against two 8-hydroxypsoralens, and conclusive evidence is presented for the existence of only one 5-O-methyltransferase and only one 8-O-methyltransferase acting on linear furanocoumarins.
Action of Citrinin on Liposomes
Authors: Ganesan M. G. , Lakshmanan M. , Ravindran K. V. , Damodaran C.
Published: August 2018

Citrinin, a mycotoxin, was studied for its effect on artificial membranes (liposomes). Of the three (net positive, negative and neutral) liposomal preparations tested, the membrane carrying a net positive charge was preferentially acted upon by citrinin and in this case even the lowest con­ centration was found to be sufficient for causing a high degree of damage. This is the first report of evidence that citrinin has a direct effect on membranes. It was shown to exhibit concentration dependency in its lytic activity on artificial membranes leading to leaching of trapped 45Ca2+ ions.
The Effect of Antibodies to Violaxanthin on Photosynthetic Electron Transport
Authors: Lehmann-Kirk Ursula , Schmid Georg H. , Radunz Alfons
Published: August 2018

An antiserum to violaxanthin in hibits photosynthetic electron transport between water, iodide or tetramethylbenzidine and various electron acceptors in chloroplasts from green tobacco (Nicotian a tabacum var. John William’s Broadleaf). However, electron transport from manganese or diphenyl-carbazide to these acceptors is not impaired. The typical photosystem I reaction from DPIP / ascorbate to anthraquinone-2-sulfonate in the presence of DCMU shows no inhibition. From this it is concluded that the effect of violaxanthin on the photosynthetic electron transport chain lies on the oxygen-evolving side of photosystem II before the site from which diphenylcarbazide or manganese donate electrons.

In the presence of DCMU after preillumination we find an effect of the antiserum on fluorescence.

The reaction of the antibodies to violaxanthin with stroma-freed chloroplasts depends on the condition of the thylakoid membrane. Chloroplasts which are still swellable react in a bivalent manner and are agglutinated. Non swellable chloroplasts react only in a monovalent manner. This specific binding was demonstrated by means of the Coombs-test.

From these reactions it follows that the antigenic determinants of violaxanthin are accessible to the antibodies, hence, they must be located in the outer surface of the thylakoid membrane.
Physico-Chemical Studies of Isolated Chromatin Compared with in situ Chromatin after Partial Hepatectomy in the Rat
Authors: Miller Paul , Linden Walfried A. , Nicolini Claudio
Published: August 2018

Chromatin was isolated from rat liver cells at 0, 3, 5, 11, 18 and 24 h following partial hepatectomy. Consistent with findings in cultured cells stimulated to proliferate, there was an increase in chromatin molar ellipticity measured at 276 nm, and a decrease in thermal stability 3 to 8 h after surgery. These events occured prior to the onset of DNA synthesis. These early changes be­ tween non-proliferating (G0) and proliferating (G1) cells, as well as later chromatin conformational changes observed at S and G2 phases, mimic changes in template activity.

Results with sheared and unsheared chromatin (both with in vitro and in vivo systems) prove that structural and functional changes can be caused by even the slightest shearing during chromatin preparation, suggesting the loss of native chromatin organization. To eliminate this problem, experiments were also conducted using chromatin in situ. A flow cytometer (FCM) was used to study unfixed liver cell suspensions stained with ethidium bromide (EB). Fluorescence was mea­ sured in the green spectral range after addition of increasing amounts of EB. Experimental evidence is provided that the same alteration in chromatin conformation can be best detected using low molar ratios of EB per unit DNA due to greater fluorescence emission in G1 respect to G0 cells.

These correlated studies demonstrate that the same changes controlling chromatin organization in situ are detected also in the tertiary-quaternary structure of “isolated” chromatin. These changes in chromatin conformation are macromolecular events related to cell proliferation both at the G0 -G1 and G1 -S transitions.
Free-Running Human Circadian Rhythms in Svalbard
Authors: Johnsson A. , Engelmann W. , Klemke W. , Ekse Aud Tveito
Published: August 2018

The body temperature, activity-rest time, electrolytes of urine samples and mood was measured in two persons during a 19 day period under continuous light conditions in the arctic (vicinity of Ny Ålesund, Svalbard-Spitsbergen). For temperature recording a new thermoprobe and a portable printer was used. Possible week Zeitgeber of the 24 hour day did not synchronize the circadian system, since circadian rhythms of about 26 hours were found. These results open up the pos­ sibility to study effects of drugs on the circadian system of humans under Svalbard conditions.
Response Characteristics and Identification of Extrinsic Mushroom Body Neurons of the Bee
Authors: Homberg Uwe , Erber Joachim
Published: August 2018

The activity of single neurons with constant discharge frequencies in the area around the α-lobe of the mushroom bodies of the bee was recorded intracellularly. The spontaneous discharge frequency of these neurons ranged between 5 and 95 impulses per second. When stimulated, about 80 percent of the neurons responded to at least one of five different sensory modalities: scent; light; air current to the antennae; sugar water applied to the antennae and to the proboscis. 45 percent of the neurons responded to two or more modalities, these multimodal neurons are common in the median protocerebrum of the bee. The differentiated response pattern of the cells does not allow a simple classification. Some of the neurons were identified after the injection of the fluorescent dye Procion yellow. We found 4 neurons with arborizations in the α-lobe and the calyces of the mushroom bodies.
Phenylethylamine as a Biochemical Marker of Tiger
Authors: Brahmachary R. L. , Dutta J.
Published: August 2018

Pheromones of the tiger happen to be a mixture of amines which are “fixed” by lipids. One of these, found always in all the four tigers investigated, is phenylethylamine. This may be a biochemical marker at a species level.
Alles-oder-nichts Verhalten und Bistabilität in einem einfachen Zellmodell mit Autokatalyse vom Typ A + 2 B = 3 B / All-or-None Behaviour and Bistability in a Simple Cell Model with Autocatalysis of Type A + 2 B = 3 B
Authors: Decker P. , Saygin Ö.
Published: August 2018

Nonlinear kinetics in a chemical cell model involving only one substrate (A) and one product (B), two reactions (A → B and A + 2 B → 3 B), and passive diffusion of A and B through the cell wall, can exhibit complex behaviour in­cluding oscillations, bistability (switching) and spiking. One such system is presented, which shows three kinds of re­sponse as depending on the quantity of a stimulus - a sudden input of product B: i. no response; ii. spiking; iii. switching into an alternative steady state - i. e. an “all-or-flip-or-none” response
Preparation of 1-α-D-Arabinofuranosylbenzimidazole and Its 5,6-Dichloro Derivative, and the Direct Bromination of Benzimidazole Nucleosides
Authors: Kazimierczuk Zygmunt , Dudycz Lech , Stolarski Ryszard , Shugar David
Published: August 2018

Arabinofuranosyl Benzim idazole N ucleosides, Direct Bromination of Benzim idazole N ucleosides, 1H NMR Spectroscopy, Ultraviolet Spectra The 1-a-D-arabinofuranosides of benzim idazole and 5,6-dichlorobenzim idazole, analogues of the biologically active 5,6-dichloro-l-β-D-ribofuranosylbenzimidazole, have been synthesized by condensation of the trimethylsilyl derivative of the appropriate benzim idazole in the presence of SnCl4 with 1-O-m ethyl-2,3,5-tribenzoyl-a-D-arabinoside.

The 5(6)-m onobrom o and the 5,6-dibrom o derivatives of 1-β-D-ribofuranosylbenzimidazole and 1-α-D-arabinofuranosylbenzimidazole were then prepared by direct bromination of the latter. With 1-β-D-ribofuranosylbenzimidazole, the initial product of bromination was a 1:1 mixture of the 5-bromo and 6 -brom o derivatives; the final product was the desired 5,6-dibromo analogue. In the case of 1-αβ-D-arabinofuranosylbenzimidazole, the initial product of bromination was the 5-(or 6 -)brom o derivative, and the 5,6-dibrom o derivative the final product. The monobrom o derivatives were easily separated from the dibrom o by chromatography on Am berlite XAD-4. Identification of all of these was based on several criteria, including detailed analyses of the 1H NMR spectra.

The benzim idazole nucleoside are considerably m ore resistant to acid hydrolysis than the cor­ responding purine nucleosides. The effects of halogenation on the ultraviolet absorption spectra of the benzim idazole nucleosides are described.
Über die Bildung von Cholesterin durch Botrytis cinerea nach Lanosterinzugabe / The Production of Cholesterol by Botrytis cinerea after Addition of Lanosterol
Authors: Flesch Peter , Robbel Lutz
Published: August 2018

The fungus Botrytis cinerea, which is found on the grapes, is able to produce cholesterol after addition of lanosterol to the culture medium. The identification of cholesterol is carried out with different analytical methods including mass spectrometry. Under the same conditions ergosterol arises from squalene and not cholesterol.
Enzymatic Synthesis of Quinolizidine Alkaloids in Lupin Chloroplasts
Authors: Wink M. , Hartmann T. , Witte L.
Published: August 2018

The enzymatic sequence responsible for the biosynthesis of tetracyclic quinolizidine alkaloids could be localized in chloroplasts isolated from Lupinus polyphyllus leaves and L. albus seedlings by differential centrifugation. Upon feeding of cadaverine to isolated chloroplasts lupanine is produced as the main alkaloid. Chloroplasts treated with digitonine produce sparteine and 17-oxosparteine instead of lupanine, thus indicating that the biosynthetic sequence is interrupted. The intermediacy of 17-oxosparteine could be confirmed since exogeneous 17-oxosparteine is converted into lupanine by intact chloroplasts. 17-Oxosparteine synthase (see Z. Naturforsch. 34 c, 704 1979) the key enzyme of quinolizidine alkaloid biosynthesis could be solubilized from chloro­ plasts treated with detergents or osmotic shock.
Stoichiometric Photophosphorylation in Thylakoids from the Blue-Green Alga, Anabaena variabilis
Authors: Wax Erika , Lockau Wolfgang
Published: August 2018

A method is described for the preparation of thylakoids from the blue-green alga Anabaena variabilis which exhibit photosynthetic control. The thylakoids can be stored in liquid N 2 with little loss in activity. P/e2 ratios (num ber of ATP molecules formed per pair of electrons transported) have been determined for partial reactions of the photosynthetic electron transport chain. Electron transport from water to an electron acceptor of photosystem I is coupled to phosphorylation with a P/e2 ratio of 0.9-1.2, from water to electron acceptors of photosystem II with ratios of 0.21-0.3 , and oxidations of hydrogen carriers by photosystem I with ratios of 0.3-0.35. Electron transport in these assay systems generates a proton gradient across the thylakoid membrane (acid inside), which is decreased by the substrates of phosphorylation and by uncouplers.
The Inhibition of the Calcium Transport ATPase of the Sarcoplasmic Reticulum by Fluorescamine: Evidence for an Oligomeric Functional Unit of the Calcium Transport System
Authors: Hasselbach Wilhelm , Migala Andrea
Published: August 2018

The labelling of the protein moiety of the sarcoplasmic calcium transport ATPase by fluo- rescamine suppresses calcium transport, calcium dependent ATPase activity, protein phosphoryla­tion by [γ-32P]ATP and [32P]phosphate at different extent of amino group substitution. For the hydrolysis of para nitrophenylphosphate by the calcium transport ATPase it is shown that the relationship between the extent of amino group labelling can considerably be altered by the temperature and the presence of ethyleneglycol. It is shown that the amino residues of the phosphatidylethanolamine moiety do not contribute to the inhibiting effect of fluorescamine labelling. The observations suggest that the different functions of the calcium transport system are based on the cooperation of a varying number of calcium transport ATPase molecules.
The Paracrystalline Nature of the Purple Membrane of Halobacterium halobium I. Lattice Distortions within the Membrane
Authors: Cabarcos E. Lopez , Bermudez S. Fernandez , Calleja F. J. Baltá
Published: August 2018

X-Ray diffraction patterns from oriented purple membrane of Halobacterium halobium show that the packing of proteins within the membrane has a paracrystalline structure. The paracrystalline mean distance fluctuations, g, were found to be 1.5 (± 0.1)% for the (100) packing planes of the proteins. The corresponding paracrystallite sizes are of ~ 850 Å. It is suggested that para­ crystalline lattice distortions within the membrane may be explained by conformational singularities of the proteins or by an irregular packing of adjacent proteins and lipids.
Investigations on the Mechanism of Induction of the Alkaline Phosphatase by Bromodesoxyuridine in Herpes simplex Virus Transformed Cells and the Transport of Uridine
Authors: Schneider D. , Falke D.
Published: August 2018

Addition of BrdUrd in combination with prednisolone to HSVi-transformed hamster embryo cells induces an alkaline phosphatase (AP). FdUrd enhances, dThd reduces the inducing capacity of BrdUrd and prednisolone. Induction is prevented by addition of cycloheximide or of cytosine arabinoside.

BrdUrd reduces transport and phosphorylation of exogenously applied labeled Urd, especially the amount of UTP, UDP and Urd-diphosphate sugars. The Lineweaver-Burk-plot of uridine-up­take after addition of BrdUrd reveales the characteristics of the mixed type inhibition (competi­tive-noncompetitive).
ʟ- Usnate-Urease Interactions: Binding Sites for the Ligand
Authors: García Isabel , Cifuentes Blanca , Vicente Carlos
Published: August 2018

ʟ-usnic acid inactivates urease by formation of high molecular weight aggregates which can reached by a maximum of 880 000. ʟ-cysteine partially reverses the inactivation by stimulating the appearance of active high molecular weight polymers. The existence of two class of binding points for ʟ-usnic acid on the urease molecule is proposed, the first showing high affinity for the ligand, related with the loss of activity, and the second, of low affinity, related to polymerization process.
Apparent Identity of Chromoplast and Chloroplast DNA in the Daffodil, Narcissus pseudonarcissus
Authors: Thompson John A.
Published: August 2018

A comparison of the EcoRI restriction endonuclease digest fragments from daffodil chromoplast and chloroplast DNAs on agarose gels has yielded identical results. The sum of the fragments for each DNA gives a minim um molecular weight of 98.6 × 106.
Binuclear Copper Electron Paramagnetic Resonance Signals of α-Methemocyanin of Helix pomatia
Authors: Rupp Heinz , Verplaetse Jozef , Lontie René
Published: August 2018

The binuclear electron paramagnetic resonance signals of α-methemocyanin of Helix pomatia were investigated at liquid helium temperatures. These signals were completely eliminated by the addition of fluoride and enhanced in the presence of chloride, which did not alter the saturation behavior. The triplet nature of the signal at g = 4.59 was confirmed by the low power-saturation. The addition of nitrite at pH 5.0 and 0° C yielded slowly and reversibly a seven-line half-field signal. On lowering the temperature the intensity of the triplet signals increased to the lowest temperature reached 4.2 K, excluding a strong exchange coupling.
Identification, Properties and Genetic Control of UDP-ʟ-Rhamnose: Anthocyanidin 3-O-Glucoside, 6″-O-Rhamnosyltransferase Isolated from Retals of the Red Campion (Silene dioica)
Authors: Kamsteeg John , Brederode Jan van , Nigtevecht Gerrit van
Published: August 2018

An enzyme catalyzing the transfer of the rhamnosyl moiety of UDP-ʟ-rhamnose to the 6 -hydroxyl group of the 3-O-bound glucose of anthocyanidin 3-O-glucosides has been demonstrated in petal extracts of Silene dioica plants. The enzyme activity is controlled by a single dominant gene N; no rhamnosyltransferase activity is found in petals of n/n plants. The 60-fold purified rhamno-syltransferase exhibits a pH optimum of 8.1, has a molecular weight of about 45000 daltons, is stimulated by the divalent metal ions Mg2+, Mn2+ and Co2+, and has a “true Km” value of 0.09 mᴍ for UDP-ʟ-rhamnose and 2.2 mᴍ for cyanidin 3-O-glucoside. Pelargonidin 3-O-glucoside and delphinidin 3-O-glucoside can also serve as acceptor. The enzyme can also catalyze the rhamnosylation of anthocyanidin 3,5-diglucosides although at reduced rate. The biosynthetic pathway for the synthesis of cyanidin 3-rhamnosylglucoside-5-glucoside in petals of S. dioica is discussed.
Evidence for Intermediate Metastable States during Equilibration of Bone and Dental Tissues
Authors: Dnessens F. C. M. , Verbeeck R. M. H.
Published: August 2018

Experimental data were collected on the solubility equilibrium of the mineral of bone, tooth enamel and calcium phosphate renal stones. Evaluation in the form of potential diagrams of Ca(OH)2 versus H3PO4 shows that Ca/P ratios of 1, 4/3, 10/7, 3/2 and 5/3, related to phases like brushite, octocalcium phosphate, whitlockite, defective apatite and hydroxyapatite respectively can be important. These facts allow the interpretation that many of these calcium phosphates are present simultaneously in biominerals or that they are formed during the equilibration.
A Study of the Substrate and Inhibitor Specificities of AMP Aminohydrolase, 5′-Nucleotidase, and Adenylate Kinase with Adenosine Carboxylates of Variable Chain Length
Authors: Meyer Wilfried , Follmann Hartmut
Published: August 2018

A series of AMP analogs in which a terminal carboxylate residue, linked to C4′ of the ribose moiety of adenosine by zero, one, or two methylene groups (1, 2 ,3) or by the unsaturated ethylidene link (4) replaces the phosphate anion, is tested for activity as substrates or effectors of three enzymes known to interact with AMP with a different degree of specificity. 2 - 4 are substrates of AMP aminohydrolase, 3 and 4 are competitive inhibitors of adenylate kinase, and all acids produce competitive inhibition of the least specific enzyme, 5′-nucleotidase. These activities can be cor­ related with the intramolecular flexibility of anionic substituent and adenine base which in turn is expressed in typical shifts of the proton magnetic resonance signal of purine H-8. The uronic acid 1, having a rigid molecular conformation, is inactive towards two AMP-dependent enzymes and little active with the third, indicating that this type of compound is not suitable as a nucleotide an­ tagonist whereas nucleoside carboxylates of type 2 and 3 have a higher potential as effectors of nucleotide metabolism.
Culture Density and Age-Dependent Interactions of 3T3 and SV3T3 Cells with Immobilized and Soluble Lens Culinaris Lectin
Authors: Kinzel Volker , Richards James
Published: August 2018

Short term binding of both Balb/c derived 3T3 cells and SV 3T3 cells to 2B-Sepharose coated with Lens culinaris lectin (LCL) was compared with their LCL-induced agglutinability in relation to culture density and age. The cells were grown for 4 days either to low (LD) or to high density (HD); for certain experiments HD-cells were stimulated (HDS) by a short trypsin treatment and/or by addition of fresh medium. HD-3T3 cells bound somewhat faster to immobilized LCL than LD-3T3 cells, although LD-3T3 cells agglutinated at lower LCL concentrations. In the case of SV 3T3 cells, binding was much less pronounced for HD than for LD cells. The agglutinability of HD-SV 3T3 cells, however, was greater than that of the other transformed groups. Upon stimulation, binding and agglutinability data of both HD cell lines began to resemble the results obtained with LD-cells. Taken together, the data revealed in all cases an inverse relationship between bind­ing and agglutinability, i. e., high agglutinability was closely correlated with slower binding and vice versa. The results indicate that culture density and age-dependent differences in cell surface architecture can be detected by short term binding to immobilized LCL.
Inhibition by Tetranitromethane of Photosynthetic Electron Transport from Water to Photosystem II in Chloroplasts
Authors: Sane P. V. , Johanningmeier Udo
Published: August 2018

Low concentrations (10 µM) of tetranitromethane inhibit noncyclic electron transport in spinach chloroplasts. A study of different partial electron transport reactions shows that tetranitromethane primarily interferes with the electron flow from water to PS II. At higher concentrations the oxidation of plastohydroquinone is also inhibited. Because diphenyl carbazide but not Mn2+ ions can donate electrons efficiently to PS II in the presence of tetranitromethane it is suggested that it blocks the donor side of PS II prior to donation of electrons by diphenyl carbazide. The pH dependence of the inhibition by this protein modifying reagent may indicate that a functional-SH group is essential for a protein, which mediates electron transport between the water splitting complex and the reaction center of PS II.
Isolierung von 7-Chorindol-3-acetamid aus Pseudomonas aureofaciens ATCC 15926 / Isolation of 7-Chloroindole-3-acetamide from Pseudomonas aureofaciens ATCC 15926
Authors: Salcher Olga , Pée Karl-Heinz van , Lingens Franz
Published: August 2018

7-Chloroindole-3-acetamide and indole-3-acetamide were enzymatically formed from crude extracts of Pseudomonas aureofaciens supplemented with 7-chloro-ʟ-tryptophan or ʟ-tryptophan. The metabolites were identified by UV-, IR-, GC-MS-spectra.
Glutamate Dehydrogenase from Medicago sativa L., Purification and Comparative Kinetic Studies of the Organ-Specific Multiple Forms
Authors: Nagel Marianne , Hartmann
Published: August 2018

NAD-specific glutamate dehydrogenase [L-glutamate: NAD + oxidoreductase (deaminating) EC 1.4.1.2] from Medicago sativa constitutes organ-specific patterns of isoenzymes. The isoenzyme-pattems of seeds (GDH-I) and roots (GDH-II) were purified 1520-fold and 92-fold, respectively. All isoenzymes of both patterns remain stable throughout the purification procedures. Isoenzyme a7, the only isoenzyme common to both patterns was isolated from the GDH-I pattern. The three enzyme preparations were found to be identical in pH optima, substrate specificity and general kinetic properties. A comparative kinetic analysis revealed no pronounced differences between the various kinetic constants evaluated for the three enzyme preparations. Furthermore an identical order of substrate binding and product release could be established. Both initial rate measure­ ments and product inhibition studies are consistent with an ordered ternary-binary kinetic mecha­ nism. The results suggest that tissue-specific enzyme multiplicity of plant glutamate dehydrogenase is not related to differences in general or kinetic properties.
Selektivdarstellung der Riechsinneszellen des Zwergwelses Ictalurus nebulosus mit Procionfarbstoffen / Selective Staining by Procion Dyes of Olfactory Sensory Neurons in the Catfish Ictalurus nebulosus
Authors: Holl Arthur
Published: August 2018

Procion Brilliant Yellow M 4RAN and Procion Yellow M 4R applied to the catfish olfactory mucosa stain intra-vitally and enter the olfactory receptors by their dendrites. The dye invades the receptor pericaryon and subsequently migrates within the axon in distal direction. Fluorescence microscopy of aldehyd fixed and paraffin sectioned preparations reveals clear selective staining of the sensory neu­ rons in yellow colour.
The Specificity of Ionophore A 23187 in Cation Transport across Lipid Membranes Studies with Lecithin Vesicles
Authors: Pohl W. G. , Kreikenbohm R. , Seuwen K.
Published: August 2018

Lecithin vesicles containing different cations were prepared by sonication and characterized. When the concentration of the divalent cations in the buffer was increased from 1 mᴍ to about 100 mᴍ the cation-concentration inside of the vesicles did not increase proportional to the outside concentration, but showed a saturation behaviour. The efflux of various cations mediated by ionophore A 23187 was measured and relative transport-rates were determined. The following sequence was obtained:

Zn2+ > Mn2+ > Ca2+ > Mg2+ > Sr2+ ⪢ Ba2+ ≈ Li+ > Na+.

The efflux of Ca2+ increased proportional to the square of the A 23187-concentration. To lecithin-vesicles containing ethylenediamine tetraacetate (EDTA) inside different cations were added on the outside. In the presence of A 23187 divalent cations are transported into the vesicles and bound there by EDTA. During the influx of Me2+-ions into vesicles a H+-efflux was observed. The resulting pH-decrease was measured. The rate of the pH-change depended on the Me2+-ion used. The sequence was:

Cd2+ > Zn2+ > Ca2+ > Mn2+ > Mg2+ ⪢ Sr2+, Ba2+.
Weitere Charakterisierung einer Chlorogensäure-Hydrolase aus Aspergillus niger / Further Characterization of a Chlorogenic Acid Hydrolase from Aspergillus niger
Authors: Schöbel B. , Pollmann W.
Published: August 2018

In addition to our previous paper [1] further characteristics of the chlorogenic acid hydrolase are described. Polyacrylamid gelelectrophoresis revealed only one band for the purified enzyme. Sodium dodecyl-sulfate polyacrylamid gelelectrophoresis showed a molecular weight of 60000, demonstrating four subunits of the enzyme (total molecular weight 240000). The enzyme is stable in a pH-range of 3 .0 -8 .5 and up to a temperature of 55 °C. The temperature coefficient Q10 is 1.5, the activation energy EA is 6.0 kcal/mol. The amino acid analysis and substrate specificity data are given in tables. Essential for the enzyme activity is the C=C double bound neighbouring the ester linkage. The enzyme crystallizes in prisms.
Evidence for the Participation of a 5-Oxo-prolinase in Degradation of Glutathione in Nicotiana tabacum
Authors: Rennenberg Heinz , Steinkamp Reinhard , Polle Andrea
Published: August 2018

During degradation of glutathione in tobacco suspension cultures substancial amounts of 5-oxo-proline are formed in vivo as well as in crude cell homogenates in vitro. The existance of a 5-oxo-prolinase that catalyzes the conversion of 5-oxo-proline to glutamic acid was demonstrated in tobacco cells, grown with glutathione as sole sulfur source.
Randomization of the Flavonoid A Ring during Biosynthesis of Kaempferol from [1,2 -13C2] Acetate in Cell Suspension Cultures of Parsley
Authors: Light Robley J. , Hahlbrock Klaus
Published: August 2018

Cell suspension cultures of parsley (Petroselinum hortense) were incubated with [l,2-13C2]ace-tate during a period of active flavonoid production. The flavonoid glycosides were extracted with ethanol, hydrolyzed in dilute acid, and the aglycones purified by chromatography. Apigenin, a flavone, and kaempferol, a flavonol, were analyzed at 67.9 MHz by 13C FT NMR. The 13C enrich­ ment confirmed that acetate contributes primarily to the flavonoid A ring. The coupling patterns between adjacent 13C atoms of the A ring indicate that the cyclization direction of the A ring is random in both compounds. While randomization of apigenin could have occurred chemically through opening of the pyrone ring under the acid conditions used for glycoside hydrolysis, ran­ domization of the more stable flavonol must have occurred biosynthetically. The latter result supports the conclusion that a chalcone is an intermediate in flavonoid biosynthesis.
Derivative Absorption Spectroscopy of the Pigment-Protein Complexes from Rhodopseudomonas capsulata
Authors: Talsky Gerhard , Rygersberg Comelis P. , van Grondelle Rien , Feick Reiner , Drews Gerhart
Published: August 2018

The near infrared absorption spectra and their fourth derivative were measured in membrane preparations or in the isolated light harvesting pigment-protein complex B 800-850 from Rhodopseudomonas capsulata in order to know how the underlying molecular absorption spectra contribute to the observed absorption curve. In contrast to the observations of Cogdell and Crofts [Biochim. Biophys. Acta 502, 409 (1978)] no splitting of the 855 nm absorption bands was observed at 300 K, 100 K, and 4 K. However, a small but significant splitting of the 870 nm band in all derivates (2nd, 4th, 6th) was observed at 300 K and 4 K. The lack of splitting of the 855 nm absorption band will be discussed in the light of the molecular organization of the B 855 moiety of this light harvesting bacteriochlorophyll-protein complex.
Radioprotective and Radiosensitizing Effects of Sulfur-Containing Amino Acid Derivatives on Mice
Authors: Nishimura Akihisa , Hashimoto Michinobu , Konno Katsunobu , Ohta Yasuhiko , Tahara Satoshi , Nishimura Hiroyuki
Published: August 2018

Both protection and sensitization of Mice C57BL against 60Co γ-rays by sulfur-containing amino acid derivatives - S-alkyl-L-cysteines, S-alkyl-2-methyl-DL-cysteines and their hydantoin derivatives, and sulfoxides of these compounds - were examined. DL-5-Allylthiomethyl-5-methylhydantoin (150 mg/kg body weight) had a remarkable radioprotective effect. The survival ratio was 4.33 or above two times as much as that of L-cysteine. On the other hand, its sulfoxide had a radiosensitizing effects; survival ratio, 0.333.
Subcloning of the Histone DNA Sequences of Phage Lambda Sam 7 h 22 in Plasmid pBR 322
Authors: Aulehla-Scholz Ch. , Jacob E.
Published: August 2018

The histone DNA sequences of the Hind III cluster of the sea urchin Psammechinus miliaris which are carried by the chimeric phage DNA of λ Sam 7 h22 have been subcloned in plasmid pBR 322. Due to this procedure single segments of the cluster have been separated from each other and are available as gene specific hybridization probes.
Light Diffraction of in vitro Crystals of Six Tobacco Mosaic Viruses
Authors: Kreibig U. , Wetter C.
Published: August 2018

Iridescent gels of the common, tomato mosaic, para-tobacco mosaic, ribgrass mosaic, sunnhemp mosaic, and cucumber 4 tobacco mosaic virus strains were prepared using the purification method of Boedtker and Simmons (J. Amer. Chem. Soc. 1958). Macrocrystals which were stable for many months could be grown from iridescent gels of all viruses when stored at 0-10 °C. The gels exhibited various structural phases (nematic and smectic) differing in density. The structure of the microcrystalline gels and of macrocrystals was investigated by means of optical diffraction. Distinct Bragg reflections were observed from which a mean periodicity of 340 nm was derived for all virus strains. The results indicate a crystalline multilayer structure as first proposed by Oster (J. Gen. Physiol. 33, 445, [1950]). The angular positions and widths of the Bragg reflections depended on the concentration of virus and the ionic strength. The periodicity decreased from 365 nm at 30 mg/ml virus to about 315 nm at 109 mg/ml virus, i.e. the periodicity approached the 300 nm length of the virion. Model calculations taking into account Debye-Hückel repulsive and van der Waals attractive forces gave a qualitative explanation for the crystalline structure and its observed concentration dependence. The in vitro crystals resemble immature crystal forms observed in the living cell.
A vena Coleoptile Segments: Hyperelongation Growth after Anaerobic Treatment
Authors: Hager A.
Published: August 2018

Avena sativa coleoptile segments show an anomalous increase in elongation growth following a short period of oxygen deprivation (tested between 0 and 60 min) lasting 20-30 min (Anaero-biosis-Aerobiosis transition effect = ANA effect). The increase in growth rate is 600% and is commensurate with that observable following an auxin treatment. This hyperelongation growth, in contrast to the auxin-induced growth, begins without a lag phase.

The growth “burst” following anaerobiosis is similarly to auxin-induced elongation growth, and is suppressed increasingly by neutral or more alkaline buffers.

Hyperelongation growth is suppressed by respiratory inhibitors and uncouplers. A complete inhibition is effected with KCN (0.5 mM) sodium azide (0.5 mM) and CCCP (1 μM); amytal (in the range 0.5 to 1 mM) and sodium arsenate (0.1 to 1 mM) are strong inhibitors. Some of these compounds (KCN, arsenate, amytal) cause a slight increase of the ANA effect in very low concentrations, which is probably due to the K+ or Na+ ions present; on their own, these ions have a strong positive influence on the ANA effect.

During anaerobiosis the ATP level sinks around 75% and almost returns to the old value, following the supply of air, within one minute.

The cell sap pH drops from 6.3 to 5.9 during anaerobiosis within 20 min. This lowering is mainly due to an increase in lactic acid concentration. Other acids such as citric, malic, and aspartic acids show insignificant changes in concentration.

The NADH content increases during anaerobiosis, whereas that of NADPH drops almost as much.

The mentioned changes in concentration of lactic acid, NADH and NADPH return to the control value within 20-30 min; thus the differences exist as long as hyperelongation growth is under way.

Possible relationships between the mentioned chemical changes and hyperelongation growth are discussed. One of the possible explanations is the following: the lowering of the cytoplasmic pH (normally around pH 7) during anaerobiosis due to the formation of lactic acid causes an activation of H+-ATPases in the plasmalemma and ER, since their optimum activity occurs in a pH of 5.5 to 6.5. This activation causes a greater H+-excretion into the cell wall compartment, and thus hyperelongation growth following supply of air and of ATP.
ESR Investigations on Blood Treated Intravenously with Ascorbic Acid"
Authors: Lohmann Wolfgang , Bensch Klaus G. , Müller Elisabeth , Kang Sa-Ouk
Published: August 2018

The effect of 1 g of ascorbic acid, administered intravenously to healthy male and female volunteers, on blood and its constituents was investigated by means of electron spin resonance (ESR) spectroscopy and by differential hematologic examinations. The native blood ESR spectrum exhibits 2 min after injection of vitamin C a considerable increase in spin concentration and a new signal at about g = 2.005 which we previously had found to correlate to the semidehydroascorbate radical. This spectrum is identical to that obtained in acute lymphatic leukemia. While it prevails in untreated leukemic patients, spin concentration and shape of the spectrum obtained return to normal within several hours to one day in healthy individuals. Since neither in erythrocytes nor in plasma modifications could be observed, the ESR changes detected must have their origin in the leukocytes. Hematologic studies of the peripheral blood show that the number of granulocytes, lymphocytes, and thrombocytes was not drastically affected by the vitamin C injection.
An Evolutionary Tree Based on Monoclonal Antibody-Recognized Surface Features of a Plastid Enzyme (5-Aminolevulinate Dehydratase)
Authors: Schneider Hj. A. W. , Liedgens W.
Published: August 2018

We describe and discuss an evolutionary tree derived from data which were obtained using monoclonal antibodies.

Monoclonal antibodies (see e.g. Köhler and Milstein, Nature 256, 495 (1975)) were prepared against 5-aminolevulinate dehydratase (ALAD) from spinach (Spinacia oleracea) and enabled us to study 13 different ALAD antigenic determinant characters from origins as diverse as algae, mosses, ferns, gymnosperms and angiosperms.

The results show that a dendrogram based on these characters is largely in accord with evolutionary trees based on classical characters. Species, such as Chara or Gnetum, whose system­atic positions are doubtful, are separated from their alleged relatives.

ALAD from the photosynthetic bacterium Rhodopseudomonas spheroides showed antigenic similarities with the plastid ALAD enzyme from spinach, while none of the antibodies against the spinach enzyme reacted with ALAD from the blue-green alga Nostoc muscorum. This finding is relevant to the problem of the origin of plastids and shows that monoclonal antibodies may also provide a new approach to the solution of this problem.

The results imply that monoclonal antibodies will prove themselves efficient tools for taxonomic or evolutionary studies.
Einfluß von Sauerstoff auf die photosynthetische CO2-Fixierung von Synechococcus / Effect of Oxygen on Photosynthetic CO2 Fixation of Synechococcus
Authors: Döhler Günter
Published: August 2018

The cyanobacterium Synechococcus (Anacystis nidulans strain L 1402-1) was grown at +35 °C in air and in air enriched with 2.2 vol.% CO2. The effect of different oxygen concentrations (0, 2, 20, 50, 75 and 99.97 or 97.8 vol.%) was studied in low (0.03 vol.%) and high (2.2 vol.%) CO2 concentrations at + 35 °C. After exposure to a nitrogen atmosphere and low CO2 content I4C-bicarbonate was mainly incorporated into aspartate and glycine/serine. During oxygenic photosynthetic CO2 fixation label in aspartate decreased and a high degree of radioactivity could be found in 3-phosphoglyceric acid and sugar monophosphates. The Calvin cycle was the main fixing pathway in 2.2 vol.% CO2 during anoxygenic and oxygenic conditions independent on the O2 concentrations during the experiments. No oxygen enhancement of photosynthetic CO2 fixation could be found. Possible mechanism involved in CO2 fixation pathways and glycolate metabolism underlying the effect of oxygen was discussed.
An Improved Method for the Preparation of the Four Ribonucleic Acids of Cowpea Chlorotic Mottle Virus
Authors: Dickerson P. E. , Malomi M. C. , Dawson J. R. O. , Morris-Krsinich B. A. M. , Trim A. R.
Published: August 2018

The four components of the genome of cowpea chlorotic mottle virus have been prepared in a highly active and highly purified state by a method based on their resolution by polyacrylamide gel electrophoresis. Activity and purity have been confirmed by gel electrophoresis under denaturing and non-denaturing conditions, infectivity tests on whole plants, translation in an mRNA dependent rabbit reticulocyte lysate and fingerprinting of T1 ribonuclease digests after labelling with 32P at the 5′ ends of the oligonucleotide products. The quality of the RNAs obtained was superior to those previously obtained by zonal centrifugation but only comparatively small batches of whole RNA can be handled with ease.
A Sex Attractant for Sperchia in tractana Walker (Lepidoptera: Tortricidae) in New Zealand
Authors: Benn M. H. , Galbreath R. A. , Holt V. A. , Young H.
Published: August 2018

Traps baited with approx. 2:1 mixtures of (E)-, and (Z)-11-tetradecenyl acetates caught male Sperchia intrac­tana Walker in the field. Analyses of extracts obtained from virgin female moths revealed the presence of these two compounds, which are presumably the major components of the sex pheromone.
Epicuticular Leaf Flavonoids from Eucalyptus Species and from Kalmia latifolia
Authors: Wollenweber Eckhard , Kohorst Gisela
Published: August 2018

In young plants of Eucalyptus globulus the leaves are covered with a whitish epicuticular layer. This leaf wax contains small amounts of C-methylated flavones as aglycones. A novel flavone has now been identified as 5,4′-dihydroxy, 7-methoxy, 6-methyl-flavone (8-desmethyl-sideroxylin). Another minor external flavone is chrysin. On leaves of E. sieberi the flavanone pinocembrin could be detected. It is shown that the four C-methylated flavones, eucalyptin, 8-desmethyl-eucalyptin, sideroxylin, and 8-desmethyl-sideroxylin are present in the leaf wax of 8 species analyzed. The same flavones are present on leaves of Kalmia latifolia.
Studies on the Zn2+/Co2+ Exchange with Acylamino Acid Amidohydrolase from Pig Kidney
Authors: Kumpe Eckhard , Löffler Hans-Gerhard , Schneider Friedhelm
Published: August 2018

The kinetics of inactivation of the Zn2+-metalloenzyme acyl-amino acid amido hydrolase by chelating ligands were studied. The rate of inactivation by 1,10-phenanthroline is enhanced by histidine and inhibited in the presence of phenyl-alanine. Removal of the metal ion increases the heat stability and decreases the pH stability of the enzyme. Reactivation of the inactive metal free enzyme is possible with Zn2+ and Co2+. Titration of the metal free protein with a Co2+/nitrilotriacetate metal buffer revealed a dissociation constant of about 10-7 ᴍ for the Co2+ enzyme (Zn2+ enzyme = 10-10ᴍ). The Co2+ substituted enzyme is less stable than the Zn2+ enzyme. Histinide and phenlalanine protect the Co2+ enzyme against inactivation by 1,10-phenanthroline.
Different Protein-Lipid Interaction in Human Red Blood Cell Membrane of Rh Positive and Rh Negative Blood Compared with Rhnull
Authors: Dorn-Zachertz Dietmar , Zimmer Guido
Published: August 2018

1-anilino-naphthalene-8 -sulfonate (ANS) fluorescence measurements have revealed that red blood cell membrane of the Rhnull type undergoes a transition at about 16 °C. In contrast, viscosity measurements of the extracted membrane lipids showed the usually observed transition at about 18 °C.

Lower values of titratable sulfhydryl (SH) groups were observed in Rhnull membrane using 5,5′-dithiobis-(2-nitro-benzoic-acid) (Nbs2). In contrast, disulfide bonds in Rhnull membrane were estimated to be about 3 times the value of the controls.

Spin labeling experiments using 2-(3-carboxypropyl)-4, 4 dimethyl-2-tridecyl 3-oxazolidinyl-oxyl were carried out with phospholipase A2 modified membranes. The mobile part of the spectra was significantly increased on the Rhnull membrane.

In the presence of ᴅ-glucose, infrared spectrometry showed a larger reduction of the intensity of the POO-band in Rhnull membrane.

In contrast to controls, binding of the reagent diethylpyrocarbonate resulted in no significant changes of the Rhnull membrane as determined by electron spin resonance (ESR) measurements.

ᴅ-glucose transport activity was found to be at the upper level of a group of Rh positive and Rh negative persons.

It is suggested that the intensity of the polar protein-lipid interaction is reduced in Rhnull membrane.
Nitrate Photo-Assimilation by the Phototrophic Bacterium Rhodopseudomonas capsulata E1F1
Authors: Castillo F. , Caballero F. J. , Cárdenas J.
Published: August 2018

Rhodopseudomonas capsulata E1F1 bacteria photo-assimilated nitrate under anaerobic conditions, but were incapable of reducing it in the dark. The bacteria utilized dissolved N2 as nitrogen source, but the growth in the presence of nitrate was 5-fold higher. Nitrite was excreted to the medium, but not stoichiometrically with respect to nitrate consumption. Nitrate reductase is particulate and used reduced viologens or flavins as electron donors for nitrate reduction. The enzyme was inhibited in vitro by KCN, NaN3, dithioerythritol and mercurials. Ammonia and other sources of reduced nitrogen repressed nitrate reductase synthesis.
Electron Transport to Assimilatory Nitrate Reductase in A zotobacter vinelandii
Authors: Bothe Hermann , Häger Klaus-Peter
Published: August 2018

Assimilatory nitrate reductase was particle-bound in extracts from Azotobacter vinelandii. Nitrate reduction by particle fractions was dependent on NADPH and a particle-bound electron carrier. When the enzyme was solubilized from the particles by treatment with detergents, the particle-bound electron carrier could be substituted by ferredoxin or flavodoxin. Flavodoxin reduced at the expense of photoreduced deazaflavin was much more efficient than ferredoxin in transferring electrons to nitrate reductase. The addition of both ferredoxin and flavodoxin to the assays with photoreduced deazaflavin gave additive effects. With the solubilized enzyme, NADPH only poorly supported nitrate reduction even after the addition of electron carriers. The experiments indicate that A. vinelandii utilizes an electron transport chain between NADPH and nitrate reductase with some properties similar to those described for the generation of reductants to nitrogenase.
Application of Liquid Chromatography to a Study on 4-Coumarate: Coenzyme A Ligase Activity
Authors: Knogge Wolfgang , Weissenböck Gottfried , Strack Dieter
Published: August 2018

This report describes the separation of components from a 4-coumarate: CoA ligase assay by means of liquid chromatography. With the aid of polyamide column chromatography it is possible to enrich and isolate chromatographically and UV spectroscopically pure p-coumaroyl- CoA using as a solvent 0.01% NH4OH in methanol subsequent to water and methanol alone.

High performance liquid chromatography on octadecylsilane-bonded silica stationary phase allows a discontinuous determination of ligase activity. All components - ATP, Coenzyme A, pcoumaric acid, and the products AMP and p-coumaroyl-CoA - can be separated and accurately quantified within 20 min using a water-acetonitrile gradient, containing 1% phosphoric acid. The presented HPLC method may be used to affirm the accuracy of optical tests
Induction of Phytoalexin Synthesis in Soybean. Structure and Reactions of Naturally Occurring and Enzymatically Prepared Prenylated Pterocarpans from Elicitor-Treated Cotyledons and Cell Cultures of Soybean
Authors: Zähringer U. , Schaller E. , Grisebach H.
Published: August 2018

Using HPLC on a partisil column (5 μm) it was possible to separate two reaction products from an enzyme incubation of dimethylallylpyrophosphate and 3,6a,9-trihydtoxypterocarpan with a particulate fraction from elicitor-treated soybean cotyledons (Harosoy 63) or soybean cell cultures. These two products were identified by MS and 1H-NMR analysis as 2- and 4-dimethylallyltrihydroxypterocarpan. Both compounds also occur as natural products in elicitor-treated soybean cotyledons and to a smaller extent in soybean cell cultures. Introduction of the dimethylallyl substituent into trihydroxypterocarpan increases the fungitoxicity against Cladosporium cucumerinum.

Upon treatment with alkali, solutions of 3,6a,9-trihydroxypterocarpans turn to an intense red colour with λmax around 530 nm. One of the products from 2-DMA-THP could be isolated by reversed phase HPLC. According to its mass spectrum a quinoid structure is proposed for this red pigment
On a Possible Mechanism of Action of Interferon
Authors: Lohmann Wolfgang
Published: August 2018

The effect of interferon on the ESR spectra of erythrocytes treated with ascorbic acid has been investigated. This model system has been chosen since it represents identically the spectra obtained in cases with acute lymphatic leukemia. The data obtained show that small interferon concentrations increase, while larger concentrations decrease the effect produced by ascorbic acid resulting, finally, in the original erythrocyte ESR spectrum. Atomic absorption studies reveal the presence of copper which might be part of the active principle