bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ethylene Production by Isolated Chloroplasts
Authors: Elstner E , Konze J 
Published: August 2018

Abstract
Isolated chloroplast lamellae from spinach or sugar-beet leaves produce ethylene from methylmercaptopropanal (MMP) or 2-keto-4-methylmercaptobutyrate (KMB) in the light. The pH-optimum for ethylene production from M M P is 6.3; ethylene production from KMB has an apparent pH-optimum at about pH 5.
Ethylene formation in red light (90 kerg ·cm -2 -sec-1) from the above substrates is stimulated by ferredoxin and inhibited by either DCMU (10-5 м), ferredoxin together with NADP, catalase, superoxide dismutase or under anaerobic conditions. From the inhibition by either DCMU, NADP or anaerobic conditions it is concluded, that an intact electron transport system from water as electron donor to oxygen as electron acceptor is necessary for ethylene form ation. H2O2 alone does not stimulate ethylene formation from M M P or KMB. Inhibition by both catalase and superoxide dismutase support the view, that ethylene formation from M M P or KMB is driven by the OH-radical, which is formed from H2O2 and the superoxide free radical ion.
The presented data suggest that in addition to ferredoxin another membrane-bound factor is involved in photosynthetic oxygen reduction and ethylene formation. This factor (ORF = oxygen reducing factor) stimulates photosynthetic oxygen reduction in the presence of ferredoxin yielding H2O2, in addition to O2
.- , which is the product of the autooxidation of reduced ferredoxin.
During photosynthetic ethylene formation from MMP or KMB, the production of the OH-radical from H2O2 and O2.- according to
H2O2+ O2
·- → OH·+OH-+O2

(Haber and Weiss, Proc. Roy. Soc. Ser. A 147, 332 [1934], Beauchamp and Fridovich, J. Biol. Chem. 245, 4641 [1970]) seems to be the rate-limiting step.
Isolation and Characterization of Mutants of Saccharomyces cerevisiae Auxotrophic and Conditionally Auxotrophic for 5′ -dTMP
Authors: Brendel Martin , Fäth Wolfgang W. 
Published: August 2018

Abstract
An improved method for isolation of yeast m utants auxotrophic for 5′-dTM P is presented. The procedure employs the two folic acid antagonists am inopterin and sulfanilam ide (SAA). Selectiveness of the procedure depends on concentration of SAA and time of incubation.
44 mutants auxotrophic and 3 conditionally auxotrophic for 5′-dTMP were isolated. All belong to one complementation group. The corresponding gene was designated TMP1. Tetrad dissection revealed its chromosomal nature. TMP1 is not closely linked to the genes ADE2,, LEU1, ARG 4, ILV2, HIS5, LYS1 and the mating type locus. With the centromere-linked genes ARG4 and LEU1 I gene TMP1 exhibited second division segregation frequencies of 0.42 and 0.53 respectively, indicative of centromere-linkage.
Strains auxotrophic and conditionally auxotrophic for 5′-dTM P were all respiratory deficient (petite). Genetical analysis indicates that the petite phenotype is due to loss of the rho factor in cells harbouring either tmp1 or tmp1ts alleles.
Dependence of Potassium Ion and Sodium Ion Exchange on Light in the Crayfish Retina
Authors: Stieve H , Malinowska T , Sonnemann D 
Published: August 2018

Abstract
The exchange (release resp. uptake) of K+, Rb+, and Na+ ions in the isolated retina of the crayfish Astacus leptodactylus with the surrounding medium was measured using flame photometry and radioisotopic techniques.
1. The net release of K+ into a Na+ and K+ free, choline containing medium, as measured by means of flame photometry, is increased by illumination.
2. The release of 86Rb+, used as an indicator for K+, in retinas preloaded with the radioisotope is also increased during the period of illumination.
3. The net release of Na+ into a Na+ and K+ free medium containing choline, as measured by means of flame photometry, is decreased by illumination.
4. The 22Na+ uptake of the retina is increased by illumination. The increase is greater after an illumination period of 20 min than after one of 2 min.
5. The uptake of 22Na+ of the retina in the dark is increased when the retina has been previously poisoned by ouabain.
6. The results of these experiments are in agreement with the assumption that: a. Na+- ions are the main carrier of the inward current causing the depolarizing receptor potential of Astacus photoreceptor cell membranes and b. the repolarization is caused by a corresponding outflow of K+ -ions.
The Effect of the Chronic Administration of D-Amphetamine upon Circadian Changes in Amino Acids in the Pineal and Pituitary Glands of the Rat
Authors: Leonard B. E. , Neuhoff V , Tonge Sally 
Published: August 2018

Abstract
The formation of dansyl derivatives of amino acids, 5-hydroxyindoleacetic acid and histamine and their separation on polyamide plates provided a reliable and sensitive method for studying circadian changes in single pineal and pituitary glands of the rat. There appears to be no cor­relation between the circadian changes in concentrations of these substances in the pineal and pituitary glands.
Chronically administered D-amphetamine altered the circadian rhythms of 5-amino acids in the pituitary, including the putative transmitters taurine, glycine and glutamate; in the pineal gland only the rhythmical changes of lysine and 5-hydroxyindoleacetic acid were affected.
Notizen: Aktive, rhythmische Ventilation des Geruchs­ organs bei Stachelaalen (Mastacem belidae) /Active, Rhythmical Ventilation of the Olfactory Chamber in Mastacembelid Fishes
Authors: Holl Arthur 
Published: August 2018

Abstract
The mode of the olfactory ventilation in fishes of the family Mastacembelidae - tested experimentally - was found to be of an active type, depending on gill-and mandibular movements as well as on the unique structure of the nasal organ itself. This mechanism (sniffling) con­ditions high performance of olfactory information.
The pH Dependence of the Receptor Potential of the Hermit Crab Photoreceptor
Authors: Stieve H. , Malinowska T. 
Published: August 2018

Abstract
The pH dependence of the receptor potential (ReP) of isolated layers of photoreceptor cells from the hermit crab compound eye (Eupagurus bernhardus L.) was determined. Measurements were performed, using extracellular electrodes, in the range pH 3.5 - 9.5 in three different buffer systems: Tris, glycine, and phosphate.
The amplitude of the ReP was highest at pH 7.5 and decreased in more acidic and more alka­line salines (Fig. 4). Relative to the changes in ReP amplitude, the changes in time course and shape of ReP were small.
Salines of pH other than 7.5 caused an increase of the latent period but decreased the peak amplitude time and the repolarizing phase (t2).
Alkaline salines caused about the same changes in the ReP as acidic salines. The only observed difference was that repolarisation was more strongly influenced by alkaline solutions and that the plateau magnitude was depressed relatively more than the peak magnitude in acidic environments.
Of the three buffers used, Tris had the weakest influence on the ReP and phosphate buffer the strongest. In contrast to the good reproducibility of the experimental results, the reversibility of the pH effects was generally poor; the effects with glycine-buffer were more reversible than those with Tris.
Der Glutathionstatus der Rattenleber in Abhängigkeit vom Lebensalter und von akuter Belastung / The Status of Glutathione of the Rat Liver and its Dependence on the Age and Acute Stress
Authors: Harisch Günther , Schole Jürgen 
Published: August 2018

The status of glutathione in the liver of male rats as a function of their age and acute stress was investigated. Total glutathione (TG), which is measured after the reduction of liver homo-genate with NaBH4 , reduced glutathione (GSH) and disulfide glutathione (GSSG) increase with advancing age of the test animals (weights from 15 g to 350 g).
The mixed glutathione disulfides [XSSG = TG - (GSH + 2GSSG)] of all ages amount to 2.0 μmol/g liver. Subsequent to the application of a stress with Vaccineurin III i.p. (weigth of 120 g), the TG values remain the same over a period of 24 hours; GSH decreases 30 min after the stress has been applied, whereas GSSG and XSSG increase. 60 min after the application of Vaccineurin, all values are within the controlled limits. 24 hours after the stress has been applied, GSH has increased and XSSG has decreased to 0.76 μmol/g fresh weight, whereas GSSG remains within the controlled limits. The causes of these changes in the status of glutathione are discussed.
Chelate Formation of Riboflavine with Yttrium (III), Lanthanum (III), and Cerium (III)
Authors: Sekhon B.S. , Chopra S.L 
Published: August 2018

Abstract
Stepwise stability constants of the interactions of 7,8-dimethyl (ribo-2,3,4,5-tetrahydroxypentyl) isoalloxazine (riboflavine) with Y (III) , La (III) and Ce (III) have been determined at 35 and 45 °C and ionic strength of 0.05 ᴍ using Bjerrum-Calvin pH titration technique. The values of free energy (⊿G), enthalpy (⊿H) and entropy changes (⊿S) have been reported.
ᴅ-( + )-Dikaffeoyl-Weinsäure aus Endivien ( Cichorium endivia L.) / ᴅ-( + ) -Dicaffeoyl Tartaric Acid from Endives (Cichorium endivia L .)
Authors: Wöldecke M. , Herrmann K. 
Published: August 2018

Abstract
The predominant caffeic acid compound of endives has been crystallized after column chromatography on polyamide and cellulose and was identified as ᴅ -(+) -dicaffeoyl tartaric acid.
Flechteninhaltsstoffe, XIII. Physodol, ein neues Depsidon aus Hypogymnia physodes / Components of Lichen, XIII. Physodol, a New Depsidone from Hypogymnia physodes
Authors: Solberg Yngve 
Published: August 2018

Abstract
In an investigation of Hypogymnia physodes (L.) Nyl. a new depsidone Physodol has been isolated. UV, IR and HrMS studies were used in the investigation. The structure of the component is given in Scheme 1.
Reactions of a Monospecific Antiserum to Ferredoxin-NADP+ - Reductase with Chloroplast Preparations
Authors: Schmid Georg H. , Radunz Alfons 
Published: August 2018

Abstract
A monospecific antiserum to ferredoxin-NADP+-reductase inhibits the diaphorase activity of soluble ferredoxin-NADP+-reductase from chloroplasts. Two states of the molecular structure of the lamellar system have been observed, one of which is the state described earlier by Berzborn. Stroma-freed chloroplasts in this condition are not agglutinated by the antiserum, although a specific adsorption of antibodies to reductase onto the lamellar system was demonstrated by the Coombs test. However, a second type of chloroplast preparations gives direct agglutination upon addition of the antiserum. Apparently, agglutination in this state is not sterically hindered by neighboring protein structures. This type of chloroplast preparations appears swollen under the light micro­ scope, but exhibits high rates of electron transport.
Chloroplasts of three types of tobacco have been used which differ in the morphology of their lamellar systems. The green type contains a normal ratio of grana and intergrana regions whereas the other two types have extended intergrana regions with either only small grana or no partitions at all. Comparison of the maximal degree of inhibition of the NADP+-reduction in chloroplasts from these types of tobacco by the antiserum, leads to the conclusion that ferredoxin-NADP+-reductase is located in the grana and the intergrana regions of the lamellar system, in the outer surface of the thylakoid membrane.
Fettsäuren und Lipide in farblosen Algen / Fatty Acids and Lipids in Colourless Algae
Authors: Glasl H , Pohl P 
Published: August 2018

Abstract
The colourless algae, Prototheca portoricensis, Polytoma oviforme, Chlorella variegata (Chlorophyta), and Chilomonas paramecium (Pyrrhophyta) mainly synthesize the 16 : 0, 18 : 1, and partly also 1 8 : 2 and 18 : 3 fatty acids.
The major lipids formed were neutral lipids (glycerides and sterol esters) and phospholipids.
In their fatty acid content, these organisms resembled fresh water green algae. They differed from the photosynthesizing fresh water green algae, however, in containing none or very low amounts of polyunsaturated C16 acids (16 : 2 , 16 : 3) and glycolipids.
Aktivität und subzelluläre Lokalisation der Adenylzyklase im Flugmuskel von — Locusta migratoria — / Activity and Subcellular Localization of the Enzyme Adenyl Cyclase in the Flight-muscle of Locusta migratoria
Authors: Achazi R.K. 
Published: August 2018

Abstract
In the flight-muscle of Locusta migratoria the adenyl cyclase shows the specific activity of 27.4 ± 8.3 pmol cAMP/ mg protein · min. Among the fraction obtained by differential centrifugation approximately 85% of the activity recovered is located in the myofibrillar fraction, and 11% in the mitochondrial fraction.
Darstellung von Aminomethylpyrrolylmethanen aus Porphobilinogen Chemistry of Porphobilinogen Preparation of Aminomethylpyrrolylmethanes from Porphobilinogen
Authors: Bausch Jochen , Eberle Albrecht , Miiller Gerhard 
Published: August 2018

Abstract
New methods for the synthesis of the aminomethyldipyrrolylmethane and the aminomethyl-tripyrrane, which are resulting from formal head to tail condensation of porphobilinogen are de­ scribed. Porphobilinogen was used as base material in these procedures. The aminomethyl group of porphobilinogen reacts as an alkylating agent with several amines as well as with porpho-bilinogen-lactam. The condensation of porphobilinogen with its lactam gave the dipyrrolylmethane-lactam, which afforded after hydrolysis the desired aminomethyldipyrrolylmethane. The conden­ sation of the latter with porphobilinogen-lactam gave the lactam of the aminomethyltripyrrane, which was then hydrolysed to the free aminomethyltripyrrane
Triterpenoids and Related Substances of Euphorbia paralias
Authors: Rizk A. M. , Youssef A. M. , Diab M. A. , Salem H. M. 
Published: August 2018

Abstract
The study of the triterpenoids and their related substances of Euphorbia paralias resulted in isolation of ursolic acid, cycloartenol, 24-methylenecycloartenol, uvaol, a hydrocarbon fraction (n-C29 n-C35), alcohol fraction (hexacosanol and octacosanol) and a sterol fraction (β-sitosterol, stigmasterol, campesterol and cholesterol)
Kinetic of Lipoquinone and Pigment Synthesis in Green Hordeum Seedlings during an Artificial Day-Night Rhythm with a Prolonged Dark Phase
Authors: Lichtenthaler Hartmut K. , Grumbach Karl H. 
Published: August 2018

Abstract
The effect of a prolonged darkness (48 h) with a following re-illumination on the prenyllipid metabolism of chloroplasts is tested in green Hordeum seedlings. Continuous darkness induces thylakoid and prenyllipid breakdown and changes the remaining lipoquinone and carotenoid metabolism of chloroplasts to that of etioplasts. Re-illumination, in turn, reverses the effects of darkness and regenerates the photosynthetic apparatus within 24 hours by a continuous and spe­cific synthesis of certain thylakoid prenyllipids.
1. The level of chlorophylls, vitamin K1 and that of the oxidized benzoquinone forms, plasto-quinone-9 and α-tocoquinone, decreases continuously in darkness. All these prenyllipids are re­ synthesized upon re-illumination, whereby a faster destruction rate in the dark (α-tocoquinone + plastoquinone-9 > vitamin K1 > chlorophylls) corresponds to a faster re-accumulation rate in the light.
2. The concentration of the reduced benzoquinones plastohvdroquinone-9 and α-tocopherol. which are preferentially deposited in the osmiophilic plastoglobuli, increases until 24 hours of dark­ness and decreases thereafter either continuously (plastohydroquinone-9) or exhibits another strong increase (α-tocopherol). Re-illumination results only in the accumulation of the oxidized quinone forms (mainly plastoquinone-9 and little α-tocoquinone) ; the level of plastohydroquinone remains, however, almost constant with a concomitant and steady decrease in the concentration of α-tocopherol. Darkness changes the main metabolite flow in benzoquinone synthesis via the formation of α-tocopherol (a trimethyl-, phythyl-(1,4-benzoquinone derivative) and light (re-illumination) via the production of plastoquinone-9 (a trimethyl, solanesyl-1.4-benzoquinone).
3. Carotenoids are enriched throughout the dark phase (mainly xanthophylls, little β-carotene) with a higher accumulation rate than after re-illumination, which yields again a higher portion of β-carotene. The correlation of prenyl chain synthesis (phytyl chain for chlorophylls and vitamin K1, solanesyl chain for plastoquinone-9) in the light with a reduced rate of carotenoid formation is discussed with respect to prenyl biosynthesis.
4. It is concluded that breakdown and re-synthesis of thylakoids and their prenyllipds, which are described here in a prolonged dark phase with following re-illumination, also occur during natural day-night growth of plants. The turnover of the thylakoid membranes and their lipids does, however, not get visible, since the decomposition in the night is recompensated by new synthesis during day. From the destruction rate one can calculate in a first approximation the biological half life time (τ 1/2) which gives values in the range of 7 to 2,5 days for all thylakoid prenyllipids
Circular DNA in Isolated Chromoplasts
Authors: Falk Heinz , Liedvogel Bodo , Sitte Peter 
Published: August 2018

Abstract
Flower chromoplasts of Narcissus pseudonarcissus have been isolated in high purity and inte­ grity by a new procedure. From these chromoplasts circular DNA molecules in supercoiled form have been isolated and demonstrated by electron microscopy to have a contour length of about 44 μm (molecular weight about 92 x 106 daltons)
Der Einfluß von Bleiionen auf Enzyme der Chlorophyllbiosynthese / Influence of Lead-ions on Enzymes of the Chlorophyll Biosynthesis
Authors: Hampp Rüdiger , Ziegler Hubert 
Published: August 2018

Abstract
The influence of different concentrations of PbCl2 on the activity of several enzymes of the chlorophyll biosynthesis in isolated spinach chloroplasts was analyzed. The succinyl-CoA-synthetase was weakly inhibited; a concentration of 2 mᴍ PbCl2 reduced the enzyme activity for 30% only. The concentration of δ-aminoevulinic acid (ALA) after incubation of the chloroplast homogenate with the substrates for the succinyl-CoA-synthetase + ALA-synthetase (cf. Fig. 9) was increased by lower concentrations of PbCl2 (0 - 50 μm) and decreased by higher (>50 μm). This can be explained by a correspondent influence of PbCl2 on the activity of ALA-synthetase or (more probably) by a relative stronger inhibitory effect of PbCl2 on the ALA-metabolizing than on ALA-producing enzymes. δ-Aminoevulinic acid dehydratase is strongly inhibited at low concentrations of PbCl2, as it is in animals. The same is true for porphobilinogenase
8 -Methoxypsoralen macht Agrobacterium tumefaciens, Kalanchoe daigremontiana und die Tumorinduktion empfindlich für langwelliges UV / 8-Methoxypsoralen Makes Agrobacterium tumefaciens, Kalanchoe daigremontiana, and the Tumor Induction Sensitive for Long Wave UV
Authors: Beiderbeck Rolf 
Published: August 2018

Abstract
If Agrobacterium tumefaciens is treated with 8-methoxypsoralen (8-MP) and irradiated with long wave UV the subsequent growth of the bacteria is stopped whereas respiration continues for at least 7 hours. Treatment with 8-MP or UV alone has no effect.
Also the wound healing processes in Kalanchoe leaves are inhibited by simultaneous applications of 8-MP and UV. Tumor induction on Kalanchoe leaves is reduced by simultaneous treatment with 8-MP and UV of a. the inducing bacteria before infection; b. the wounded leaves before infec­ tion : c. the infected leaves at least up to 24 hours after infection.
These results are discussed in relation to a participation of bacterial or host DNA in the infec­ tion process
Growth Inhibition of Human Lymphoblastoid Cells by Interferon Preparations, Obtained from Human Leukocytes
Authors: Hilfenhaus Joachim , Karges Hermann E. 
Published: August 2018

Abstract
The growth inhibition of human lymphoblastoid cells by human interferon preparations (HIF) and a mock-interferon preparation (Mock-IF) was studied. HIF was induced in suspensions of primary human leukocytes by Newcastle Disease Virus. Mock-IF was prepared from uninduced cell suspension of a comparable batch. The highest degree of inhibition of cell propagation was ob­ tained on the EBV producer line P3HR1, the inhibition of the cell lines Raji and SKL 1 was significantly lower, no effect was observed on the cell line RPMI 1788 originating from a healthy donor. Mock-IF also caused a growth inhibition but to a lower degree as HIF. HIF and Mock-IF are similar in the following properties: 1. Stability at pH 2 at 4 °C for four days, 2. sensitivity to tryptic digestion, and 3. molecular weights in the range between 5,000 and 40,000 daltons
Darstellung und Eigenschaften von 5-Acetyl-4-methyl-1-(β -D-ribofuranosyl)- imidazol-5′ -di- und -triphosphat / Synthesis and Properties of 5-Acetyl-4-methyl-1-(β-D-ribofuranosyl)-imidazole-5′ diand -triphosphate
Authors: Johnscher Gerd , Berghäuser Jürgen , Woenckhaus Christoph 
Published: August 2018

Abstract
5-Acetyl-4-methyl-1-(β-D-ribofuranosyl) -imidazole-5′-phosphate reacts with diphenylphospho chloridate forming the asymmetrical pyrophosphate ester. This in turn reacts with tri-n-butylammonium phosphate yielding 5-acetyl-4-methyl-imidazole-riboside-5′-diphosphate and with tri-rcbutylammonium pyrophosphate to give the nucleotide triphosphate.
5-Acetyl-4-methyl-imidazole-riboside-5′-pyrophosphate shows in the test with pyruvate kinase a reaction rate three times slower than that of ADP; but the same Km as that of ADP. The ATP analogue is only about 10% as effective as ATP itself in the test with hexokinase, 3-phosphoglycerate kinase and gluconate kinase. Adenylate kinase and NAD+ kinase show no activity when ATP is replaced by the nucleotide-triphosphate-analogue. In presence of ATP the analogue strongly inhibits the reaction of adenylate kinase.
Der Einfluß von Protoplastenmedien auf die Tumorinduktion an Kalanchoe-Blättern / The Influence of Protoplast Media on the Tumor Induction on Kalanchoe Leaves
Authors: Beiderbeck Rolf 
Published: August 2018

Abstract
Experiments concerning tumor transformation of plant cells or protoplasts need complete knowledge of the effects of media components. Here inhibiting effects of cellulase Onozuka, glucose, sucrose and mannitol (up to 0.3 M) , of tissue culture media, and of the antibiotic aureo-mycin on the tumor initiation process in Kalanchoe leaves are reported. Also the influence of these substances on the growth of the tumor inducing Agrobacterium tumefaciens is studied. The results lead to the design of conditions which should be favourable to in vitro transformation.
The Effect of 5-Hydroxytryptamine and Histamine on Glycolysis in the Mouse Brain
Authors: Leonard B. E. 
Published: August 2018

Abstract
Following the intraventricular injection of 5-hydroxytryptamine into the lateral ventricles of conscious mice, the concentration of brain lactate rose immediately but then decreased significantly compared with the saline injected controls. The concentration of brain glucose increased 20 min after the injection of 5-hydroxytryptamine. These effects of 5-hydroxytryptamine on lactate and glucose were qualitatively similar to those found following the administration of methysergide. After the parenteral adm inistration of 5-hydroxytryptophan, the lactate levels showed a biphasic change but brain glucose was significantly decreased for up to 90 min following the injection. p -Chlorophenylalanine potentiated the effect of 5-hydroxytryptamine by further increasing glucose and decreasing lactate levels. After histamine had been injected into the ventricles, the concentrations of bound glycogen and lactate were decreased whereas free glycogen and glucose were raised.
It is suggested th at 5-hydroxytryptamine, and possibly histamine, are involved with control of glycolysis in the mouse brain.