bluuebunny/crossref_metadata_2025 huggingface dataset:
Photosynthetische Reaktionen in UV-bestrahlten Chloroplasten
Authors: Trebst Achim , Pistorius Elfriede
Published: March 2015

Photosynthetic reactions in isolated chloroplast fragments were investigated after they had been exposed to UV-light of 254 mμ, which is found to destroy the endogenous plastoquinone. The oxygen evolution is the most UV sensitive photosynthetic reaction. The ATP formation in the noncyclic and in the cyclic system with vitamin K5 as cofactor is less sensitive; the inactivation goes parallel to the destruction of the plastoquinone of the chloroplasts. Cyclic photophosphorylation with PMS as cofactor is diminished only after longer UV-irradiation. Photosynthetic reduction of NADP at the expense of an artificial electron donor system like DAD/ascorbate is not inactivated even after prolonged UV-exposure of the chloroplasts and therefore requires no plastoquinone. This indicates again, that the site of function of plastoquinone is close to the second light-reaction of photosynthesis.
Dehydrierung des Cholesterins im aktiviert adsorbierten Zustand unter Normalbedingungen, ein Beitrag zur Frage der Endogenese carcinogener, polycyclischer Kohlenwasserstoffe
Authors: Wilk Manfred , Taupp Werner
Published: March 2015

Die Ergebnisse einer Selendehydrierung des Cholesterins bei 350°C werden mit Produkten verglichen, die sich aus dem Steroid im aktiviert absorbierten Zustand auf Kieselgel durch Oxydation mit Joddampf bei Raumtemperatur bilden. Alkylsubstituierte Cyclopentenophenanthrene konnten hierbei mit Sicherheit gefaßt werden. Da die äußeren Versuchsbedingungen, im Gegensatz zu allen bisherigen Dehydrierungsversuchen an Steroiden, am ehesten mit physiologischen verglichen werden können (20°C, ein dem freien Sauerstoff entsprechendes Oxydationspotential von ca. +0,4 V und eine aktivierende Grenzfläche), werfen die Ergebnisse ein neues Licht auf die alte Hypothese der endogenen Bildung carcinogener Kohlenwasserstoffe im Organismus.

Der erleichterte Reaktionsverlauf im Adsorpt wird durch Erhöhung der Adsorptionswärme im Zuge der Aromatisierung erklärt.
Synthese und UV-Spektrum von Thiopyrano[4.3-b]indol
Authors: Mayer R. , Wagner R. , Fabian J.
Published: March 2015

Thiopyrano[4.3-b]indol (1) wird durch Dehydrierung von Tetra-hydro-1 mit Chloranil erhalten und durch das UVS-Spektrum charakterisiert. SCF-LCI-PPP-Berechnungen werden auf Aza-schwefelheterocyclen ausgedehnt und zur Berechnung des Spektrums von 1 verwendet.
Reoxydation der Disulfidbrücken des menschlichen Choriongonadotropins (HCG)
Authors: Schlumberger H. D. , Blobel R.
Published: March 2015

After alkylation of human chorionic gonadotropin (HCG) with iodoacetate in 4 M guanidine-HCl and in 8 M urea, 1.6 and 0.6 mole equivalents of carboxymethylcysteine were found, respectively. The biological activity of these preparations was 25% of the original specific activity.

Slow reoxidation of completely reduced HCG with oxygen yields products having 15 - 25% of the original specific activity, while fast reoxidation results in complete loss of biological activity and immunological specificity.

Immunological specificity and 25% of the original biological activity can be recovered if the disulfide bonds of the inactive sample are reequilibrated in the presence of β-mercaptoethanol.
Polarographische Messung kritischer Sauerstoffdrucke bei Herzmuskelsarkosomen
Authors: Glossmann H. , Frimmer M.
Published: March 2015

Mit Hilfe der Ganzglas-Platinelektrode nach GLEICHMANN und LÜBBERS wurde der kritische O2-Druck bei stark verdünnten Sarkosomensuspensionen in Tris-Puffer bei 37 °CC mit 2,14 ± 0.87 Torr ermittelt. Die Abhängigkeit der kritischen O2-Drucke vom Suspensionsmilieu (Tris- und Phosphatpuffer) sowie die Beeinflussung der Meßergebnisse durch Hämoglobin oder Myoglobin wurden untersucht.
Über das Auftreten von Pterinen, Tryptophan und dessen Derivate in verschiedenen Organen der Mutante white von Drosophila melanogaster
Authors: Bonse Angelika
Published: March 2015

It was shown that the Malpighian tubules of the white-eyed mutant of Drosophila melanogaster have few fluorescent substances, as compared with the wild type. Apparently these Malpighian tubules are not able to take up and accumulate some pteridines, tryptophan and kynurenine. These substances, found in high amounts in meconia and feces, are excreted by the hind-gut. In the pattern of the fluorescent substances of the ovaries and eggs no differences could be found between the wild type and the mutant white. The high amount of isoxanthopterin in the Malpighian tubules of the white strain of Drosophila melanogaster (Inst. of Technology, Pasadena) is due to modifier genes. These genes could be eliminated by repeated back-crossing of the strain with flies of the wild type.
Theoretical Treatment of Ohmic and Rectifying Properties of Electrolyte Filled Micropipettes
Authors: Krischer C. C.
Published: March 2015

Für Mikropipetten, wie sie in elektrophysiologischen Impedanzmessungen, Stimulation und Ioneninjektion verwendet werden, wird ein Modell angenommen, das aus einem isolierenden Kegelstumpfmantel besteht, dessen Oberfläche eine negative Ladung trägt, die durch eine leitende Kationenschicht neutralisiert wird. Unter den einfachsten Bedingungen sei die Elektrode mit einem gewöhnlichen Elektrolyten wie KCl gefüllt und umgeben. Mit Hilfe einer Konstanten b [cm], die das Verhältnis von Volumen- zu Oberflächenleitfähigkeit darstellt, wird entlang der Kegelachse das Verhältnis von Ionen in der Doppelschicht zu Ionen im Volumenelektrolyten berechnet. Für den Fall, daß der Radius der Öffnung r0[cm] ⪢b [cm] herrscht Volumenleitung in der Öffnung. Die elektrische Charakteristik ist ohmisch. Für r0 ⪡ b ist die Öffnung durch Doppelschichtladungen verstopft. Strom polarisiert diesen Stopfen derart, daß in einer Stromrichtung der Elektrolyt im stark beengten Innenraum der Elektrode angereichert (Widerstandsabnahme), in der anderen verdünnt wird (Widerstandszunahme). Die dargelegten Eigenschaften stromführender Mikropipetten werden in Hinblick auf ihre Bedeutung bei elektrophysiologischen Anwendungen diskutiert.
Some New Actinide Tetrahalide-NN Dimethylacetamide Complexes
Authors: Bagnall K. W. , Brown D. , Lux F. , Wirth G.
Published: March 2015

Protactinium tetrachloride reacts with NN dimethyl-acetamide (DMA) in anhydrous, oxygen-free carbon tetrachloride to form PaCl4 · 3 DMA. This can be degraded to PaCl4 · 2.5 DMA but this is a different crystal modification to that previously reported for the MCl4 · 2.5 DMA (M = U, Np, Pu) complexes; three different crystal modifications of the complexes of this type have now been obtained. Actinide tetrabromides form complexes of the type MBr4 · 5 DMA (M = Th, Pa and U) as well as those of the type MBr4 · 2.5 DMA (M = Pa and U only). Reactions in acetone result in the formation of adducts of the type MBr4 · 4 DMA • CH3COCH3 (M = Th and U only). The preparation and interconversion of the various types of complex are discussed and some chemical properties, infrared spectra, NMR spectra and X-ray powder diffraction results are reported.
Stoffwechsel aromatischer Pflanzeninhaltsstoffe I
Authors: Barz Wolfgang
Published: March 2015

The turnover of the isoflavones, formononetin and biochanin A, in Cicer arietinum L. and of the isoflavone, daidzein, and the coumestan, coumestrol, in Phaseolus aureus Roxb. has been determined by pulse labelling. The biological half-life of formononetin, daidzein and coumestrol has been found to be approximately 50 hours, while the turnover of biochanin A appeared to be very slow. The excretion of all four plant products through the roots into the medium has been measured. Approximately 3 percent of the total turnover of isoflavones in the plants can be accounted for by excretion into the medium.

The results are discussed in view of the concept that secondary plant products may well be subject to further metabolism.
Die Dehydratisierung von Alkoholen an Aluminiumoxid.
Authors: Knözinger Helmut , Bühl Horst
Published: March 2015

Die Reaktionsgeschwindigkeiten der Atherbildung aus Alkoholen an Aluminiumoxid lassen sich mit Hilfe der Taft - Gleichung korrelieren. Es wird ein im Rahmen eines früher 17, 19 postulierten Mechanismus möglicher Übergangszustand vorgeschlagen, der die gefundene Abstufung von Reaktionsgeschwindigkeit und Aktivierungsentropie allein durch induktive Einflüsse der Substituenten deuten läßt.
Zur Struktur einiger Hydroxy-piperidon(2)-Derivate
Authors: Kessler Horst , Möhrle Hans
Published: March 2015

Die bislang angenommene Struktur 1 b für das Produkt der Hg (II) -ÄDTA-Dehydrierung des Benzilsäureesters von 3-Hydroxy-N-methylpiperidin wird durch dessen NMR-Spektren widerlegt und dafür die Konstitution 1 a bewiesen. In einer Reihe analog dargestellter Verbindungen wurde der ó-Valerolactam-Charakter bestätigt und gleichzeitig die magnetische Nichtäquivalenz (MNE) geminaler Protonen untersucht. Die Aufspaltungen und die Unterschiede in den Kopplungskonstanten in Abhängigkeit von den Substituenten zeigen, daß hier eine Deutung der MNE ausschließlich durch sterische Effekte oder durch Wasserstoffbrücken allein nicht zulässig ist.
Photoreactivity (3655 Å) of various skin-photosensitizing furocoumarins with nucleic acids
Authors: Dall’Acqua F. , Marciani S. , Rodighiero G.
Published: March 2015

The photoreaction at 3655 A between skin-photosensitizing furocoumarins and DNA leads to a photo-C4-cyclo-addition reaction in which the 5 - 6 double bond of the pyrimidine bases and the 3 -4 or the 4' -5′ double bond of the furocoumarins are involved. In continuing the research in this field, the authors have investigated the photoreactions (3655 A) of psoralen, xanthotoxin (8-methoxy-psoralen), bergapten (5-methoxy-psoralen) and 8-methyl-psoralen with native calf thymus DNA. with heat-denatured DNA and with ribosomal yeast-RNA, using labelled furocoumarins and examining also the influence of the temperature at which the irradiation was made. At room temperature (22° -30°C) psoralen photoreacts in almost equally extent with each of the three nucleic acid samples, while xanthotoxin, bergapten and 8-methyl-psoralen photoreact to a greater extent with native DNA than with denatured DNA and RNA.

The temperature during the irradiation (in the range examined: 2° - 30°C) does not affect the rate of the photoreactions between the four furocoumarins and native DNA, whereas it has an evident influence on the photoreactions with denatured DNA and with RNA. In the photoreaction of psoralen this influence concerns the double bond (3 - 4 or 4' -5′) of the furocoumarin which is engaged in the C4-cycloaddition to pyrimidine bases. In the case of the other furocoumarins, the rate of the photoreactions is affected: at 2° - 8°C it is greater than at 30 °C. The preliminary formation (in the dark) of a complex between the furocoumarins and the macromolecules is involved in this temperature influence.
Permissible Base Sequences for non Self Complementary Messenger RNAs
Authors: Friedmann E. , González J. , Gampel Z. , Pieber M. , Romero C. , Tohá C. J.
Published: March 2015

It is a well accepted assumption that the transcription of DNA is done along a single strand (TOCCHINI-VALENTINE and cols.1, SPIEGELMAN and HAYASHI 2, MARMUR 3 and TOHÁ C. 4) and that the biosynthetic mRNA obtained is monoteonic and is read in a linear fashion during the process of translation. In order to have a good interaction with the ribosome and an easy reading of the message the mRNA should remain extended (OKAMOTO and TAKANAMI5; KHORANA6). We assume that this state is due to a lack of complementary zones in the strand of mRNA. If the assumption is valid, we can imagine that the sequences of basis in the messenger is substantially limited by this restriction that excludes the existence of complementary zones.
Studies on the chemistry of lichens
Authors: Solberg Yngve Johannes
Published: March 2015

The Norwegian lichen species Lecanora (Aspicilia) Myrinii has been chemically investigated with regard to its content of aromatic lichen compounds, hydroxy fatty acids, soluble and bound sugars, and amino acids. Norstictic acid and a tetrahydroxy fatty acid have been isolated. In addition to these two compounds, free galactose, glucose, mannose, sucrose, fructose and 33 ninhydrin-positive compounds were detected in a water extract. The polysaccharides and the protein part of the lichen material were determined after hydrolysis. Great amounts of glucosamine were found in the protein fraction.
Photo- und Halbleitfähigkeit von Festkörpern isomerer und tautomerer Moleküle
Authors: Rau Hermann
Published: March 2015

In dünnen Schichten von 1-Benzolazo-2-naphthol liegen Azo- und Hydrazonform der Molekel in verschiedenen Verhältnissen nebeneinander vor, wie man den Spektren entnehmen kann. Trotzdem findet man nach σ=σ0 exp[—ΔE/2 kT] nur eine Aktivierungsenergie der „bulk“-Leitfähigkeit von 1,55 eV. Daneben tritt eine Oberflächenleitfähigkeit auf, die durch eine Aktivierungsenergie von 2,0 eV gekennzeichnet ist. Hier spielen tiefe Fallen eine entscheidende Rolle.
Kinetik der Hydrierung des homogenen Katalysators Ir(CO)XL2 als Funktion der Liganden X und L
Authors: Strohmeier W. , Onoda Takeru
Published: March 2015

Die Reaktivität des homogenen Hydrierungskatalysators Ir (CO) XL2 in bezug auf die Wasserstoffaufnahme unter Bildung des Hydridkomplexes Ir(CO)XL2H2 wurde als Funktion der Liganden X (Cl, Br, J) und L (phosphorhaltige Verbindungen) untersucht. Die Reaktivität nimmt als Funktion der geladenen Liganden X in der Reihe Cl < Br < J zu. Bei Variation der ungeladenen Liganden L hängt die Reaktivität von der Elektronendichte am Reaktionszentrum Ir ab.
Das Phenoxymethyl-Radikal
Authors: Joschek Hans-Ingo , Grossweiner Leonard I.
Published: March 2015

Bei der Bestrahlung von Anisol in Wasser entstehen neben dem hydratisierten Elektron das Phenoxyl- und das Phenoxymethyl-Radikal. Das Dimerisationsprodukt des Phenoxymethyl-Radikals, 1.2-Diphenoxyäthan, konnte aus den Produkten der 3660 Å-Bestrahlung identifiziert werden.
Optimierung der oxydativen Spaltung mit MnO4
⊖/JO4
⊖.
Authors: Grimmer Gernot , Jacob Jürgen
Published: March 2015

Zur Lokalisation von Doppelbindungen in ungesättigten Fettsäuren wird eine Mikromethode (ca. 1 mg) zur Spaltung mit MnO4/JO4 beschrieben. Nach der Veresterung der bei der oxydativen Spaltung entstehenden Mono- und Dicarbonsäuren wird dieses Gemisch gaschromatographisch getrennt und die FID-Signale der Einzelkomponenten elektronisch integriert. Unter optimalen Bedingungen der molaren Verhältnisse und der Reaktionszeit ist eine Nebenreaktion (Überoxydation) weniger als 0,5% der Hauptreaktion (R1CH=CHR2 → R1COOH + HOOCR2).

Die Genauigkeit erlaubt eine Analyse von Gemischen, deren Komponenten (Positionsisomere) mehr als 0,5% betragen.

Die Methode ist an reinen ungesättigten Fettsäuren getestet. Homogene Testsubstanzen wurden durch die Hydrierung entsprechender Acetylencarbonsäuren mit Hydrazin in Methanol ohne Isomerisierung hergestellt. Bei diesem Verfahren beträgt die Verschiebung der Doppelbindung in die Nachbarstellung weniger als 0,5 Prozent. Es wird nur die cis-Form gebildet.
Chemie nucleophiler Carbene XV
Authors: Wanzlick Hans-Werner , Lachmann Burkhard
Published: March 2015

Die Umsetzung von Bis-[1.3-diphenyl-imidazolidinyliden-(2)] (1) mit Tetracyanoäthylen gibt kein Cyclopropan-Derivat. über ein isolierbares Radikalsalz 3 wird das Pentacyanopropenid 5 erhalten.
Thermal Denaturation Equilibria of TMV Coat Proteins with Chemically Defined Differences in their Primary Structure
Authors: Jockusch H. , Koberstein R. , Jaenicke R.
Published: March 2015

Thermal denaturation of RNA free coat proteins of tobacco mosaic virus (TMV) was studied for wildtype TMV (vulgare) and the temperature-sensitive mutant, Ni 118. The ability to form soluble aggregates as well as the optical properties (ORD, UV-difference spectra), and the sedimentation behavior were used as criteria for the native state.

At pH 7.5, I= 0.02 denaturation is reversible for both proteins. The ORD data indicate that the denatured proteins contain residual secondary structure. The “melting temperatures”, as defined by ORD measurements (cp = 0.02 mM), are 39.5 ± 1°C for vulgare and 27 ± 1°C for Ni 118 at pH 7.5, I= 0.02. By means of the aggregation test (cp = 0.05 mM) somewhat lower melting temperatures were found under the same solvent conditions. The difference between the primary structures of vulgare and Ni 118 proteins being a proline → leucine (pos. 20) replacement, the results suggest the cyclic structure of proline (20) to have a specific stabilizing function in the three dimensional protein structure. This conclusion is supported by preliminary experiments on a temperature-sensitive mutant with a threonine residue in pos. 20.
Radioprotective Properties of Some Heterocyclic Nitrogenous Compounds Against X-radiation Injury to Serum Proteins in Mice
Authors: Roushdy H. , Pierotti T. , Polverelli M.
Published: March 2015

The results obtained from this study suggest the following: The concentration of total serum proteins in mice is changed very little under the various treatments, while protein fractions showed significant alterations.

The concentrations of various serum proteins remain almost constant under normal conditions.

Intraperitoneal administration of imidazole or benzimidazle at the mentioned doses induces rapid quantitative changes in the serum which are recovered in about 3 days after injection.

Whole-body X-irradiation at 750 r creates slow but progressive and persisting serious changes in concentration of serum protein fractions which end in death of animals 8 — 10 days after irradiation.

Whole-body X-irradiation of imidazole or benzimidazole protected animals results in quantitative rapid changes in concentration of serum protein fractions for about four days. There after a slow but steady restoration begins. The concentration approaches the normal levels towards the 10th day after irradiation.

Imidazole and benzimidazole proved to be good radioprotectants against the effects of X-radiation on serum protein fractions. Benzimidazole seems to surpass imidazole.
Das sterische Verhalten der Alpha-Helix / The steric Behaviour of the Alpha-Helix
Authors: Jarosch R.
Published: March 2015

The steric behaviour of the α-Helix has been investigated using an elastic molecule-model made of solid rubber balls and steel pins. Shortening of the hydrogen-bonds, which is possible at least in the range from 2.91 to 2.67 A in real α-Helices, has the following effects:

1. The α-Helix contracts proportionally to the length of the hydrogen-bonds (figs. 3, 4).

2. A torsional force arises leading in the case of longer α-Helices to torsional revolutions of the free ends of the helix (figs. 3 a. 4 a).

3. Tertiary structures (superhelices. flattened superhelices. planar wavy lines, planar arcs) superpose the α-Helix if only specific hydrogen-bonds (e. g. indicated by arrows in fig. 5) will be shortened and if the distance between them is repeated in the sequence of the polypeptide chain (Tab. I). Some of the sequence-distances show similar tertiary structures and the same pitches of the superhelices (Tab. II). A general variation in the length of the hydrogen-bonds causes alterations in the superstructure and can also change the coiling direction of the superhelix.

4. The Cα— Cβ; bonds incline slightly to the axis of the helix (fig. 11) through which the α-Helix with side chains becomes a little thinner. Because of the torsion (see item 2) the distance between the side chains changes also (fig. 12). The distances increase between specific positions of the side chains and decrease between others (Tab. III).

Possible reasons for the shortening of the hydrogen-bonds are briefly discussed. The importance of the described behaviour for biological movements, enzymatic catalysis (“allosteric effect”) and active transport is emphasized.
Über die intrazelluläre Mg-Ionenaktivität von E. coli-Zellen
Authors: Günther Th. , Dorn F.
Published: March 2015

Die Mg-Ionenaktivität in E. coli-Zellen wurde mit einer Mg-empfindlichen Elektrode bestimmt.

Die intrazelluläre Mg-Ionenaktivität ist bei einer extrazellulären Mg-Konzentration unter 10-3 M wesentlich höher als die extrazelluläre und nahezu unabhängig von der extrazellulären Mg-Konzentration. Bei hohen extrazellulären Mg-Konzentrationen ist die intrazelluläre Mg-Ionenaktivität niedriger als die extrazelluläre. Wachsende Zellen haben eine etwas höhere intrazelluläre Mg-Ionenaktivität als nichtwachsende. Beim Wachsen in Mg-armen Medien bleibt die intracelluläre Mg-Ionenaktivität nahezu konstant, obwohl der Mg-Gehalt abnimmt.

Unter Mg- oder N-Mangel gewachsene Zellen nehmen bei hohen extrazellulären Mg-Konzentrationen mehr Mg auf als normale Kontrollzellen. Diese vermehrte Mg-Aufnahme wird durch 10-3 M 2.4 DNP in PO4-haltigen Medien oder durch Waschen mit NaCl-KCl-Lösung vermindert.
Morphologische Untersuchungen an Staphylokokken-Typisierungsphagen / Morphological Studies on Staphylococcal Typing Phages
Authors: Frank H. , Lorbacher H. , Blobel H.
Published: March 2015

Staphylococcus aureus phages of serological groups A, B and C could be distinguished by the size of their plaques. Electron microscopy revealed that the phages of group A differed in the lengths of their heads and tails from those of groups B and C. The terminal knob of each of the phages appeared to be a hexagonal base plate with short spikes. In group B and C phages the base plate was presumably connected to the tail by a conical middle piece.
65. Mitteilung über Flechteninhaltsstoffe.
Authors: Huneck Siegfried , Santesson Johan
Published: March 2015

Lecidea carpathica (KOERB.) SZAT. enthält neben Diploicin. Chloratranorin und Atranorin das neue Xanthon Thuringion, bei dem es sich um 2.4.7-Trichlor-1.6-dihydroxy-3-methexy-8-methylxanthon handelt.
Die Wirkung von UV-Strahlen auf die Lipochinon-Pigment-Zusammensetzung isolierter Spinatchloroplasten / Effect of uv-light on the lipoquinone and pigment composition of isolated spinach chloroplasts
Authors: Lichtenthaler Hartmut K. , Tevini Manfred
Published: March 2015

The changes in quinone and pigment composition of isolated spinach chloroplasts were investigated after treatment with UV-light of 254 mμ, which is known to decrease the Hill- reaction activity. The plastidquinones are more UV-sensitive than carotenoids (except neoxanthin) and chlorophylls. Neoxanthin, reduced plastoquinone 45 and α-tocopherol function consecutively as lipid antioxidants and are first destroyed. The latter are oxidized to the corresponding quinones plastoquinone 45 and α-tocoquinone, which thus seem to be less UV-sensitive. The decrease of the Hillreaction activity runs parallel with the decomposition of plastoquinol (= Plastohydrochinon) and not with that of plastoquinone as has been assumed so far. This indicates that plastoquinol is needed for performance of the Hill - reaction.

The naphthoquinone vitamin K1, bound to the pigment system I of photosynthesis, is less UV-sensitive than the plastidquinones of the benzoquinone type which are associated mainly with the pigment system II. The possible function of vitamin K1 as one natural cofactor of cyclic photophosphorylation is discussed.
Eine Hochdruckphase des ZnIn2S4 mit Spinellstruktur
Authors: Range Klaus-Jürgen , Becker W. , Weiss Armin
Published: March 2015

ZnIn2S4 geht bei 40 kbar, 400°C in eine Hochdruck-Modifikation mit normaler Spinellstruktur über.
Arginase- und Ureasesynthese bei Micrococcus denitrificans Beij. unter aeroben und anaeroben Kulturbedingungen
Authors: Hiort U. , Kating H.
Published: March 2015

Zum Nachweis einer adaptiven Ureasebildung werden in den Acetonpulver-Extrakten aus Micrococcus denitrificans die spezifischen Aktivitäten der Urease und Arginase nach Kultur des Organismus unter aeroben und anaeroben Bedingungen mit jeweils verschiedenen N-Quellen (NH4Cl + KNO3; Harnstoff, Ornithin, Citrullin, Arginin) bestimmt. Die Versuchsergebnisse zeigen, daß bei M. denitrificans nur Harnstoff sowohl unter aeroben als auch anaeroben Kulturbedingungen die Ureasebildung induziert (= Substratinduktion). Die Aminosäuren des Ornithin-Cyclus unterdrücken in anaerober Kultur die Ureasesynthese, obwohl Arginaseaktivität vorhanden ist. Hohe Ammonium-Konzentrationen hemmen die Ureasebildung unter beiden Kulturbedingungen vollständig ( = Endprodukthemmung). Diese Totalhemmung erfolgt in Gegenwart von Harnstoff, der durch eine Arginase freigesetzt wird, die in den auf NH4Cl + KNO3 in anaerober Kultur gezogenen Zellen die höchste bei diesem Organismus gefundene spezifische Aktivität hat.
Zum Wirkungsmechanismus von 1-Nitroso-3-nitro-1-methylguanidin (NNMG) bei der Mutationsauslösung / The Mode of Action of 1-Nitroso-3-nitro-1-methyl-guanidine (NNMG) in Mutagenesis
Authors: Süssmuth R. , Lingens F.
Published: March 2015

1. The stability of NNMG with respect to pH was investigated. A maximum, with a half-life of 40 hours, was found in phosphate-citric acid buffer at pH 5. The stability decreases quickly with increasing concentration of hydroxyl ions. At the optimal mutation rate (pH 6, 37°, and shaking) the half-live is only 14,4 hours.

2. NNMG uptake (using labelled NNMG) and mutation rate in the range pH 3,5 — 8,0 show an optimum at pH 6,0/6,5 for both Escherichia coli B and the red ad- mutant E 188 of Saccharomyces cerevisiae. The pH-dependence of NNMG uptake and mutation rate is similar.

3. The methylation of nucleic acids by means of [3H]-methyl-NNMG or [14C] -methyl-NNMG in phosphate-citric acid at 37° while shaking increases with the growing concentration of hydroxyl ions. At the optimal mutation rate, however, NNMG methylates relatively poor.

4. Incorporation of radioactive NNMG into Escherichia coli B results in labelling of nucleic acids and proteins. The labelling of DNA shows an optimum at pH 6. The extent of methylation was found to be higher in vivo than in vitro.

5. In the presence of cysteine or β-mercaptoethanol nucleic acids are methylated more intensively than in the cysteine-free control experiment. After one hour the methylation was about twentyfold higher in the presence of cysteine or β-mercaptoethanol compared to the cysteine-free control experiment. The methylation in presence of SH-compounds shows a maximum at pH 6. The explanation of both a higher methylation rate and its optimum at pH 6 suggests the activation of methylation by means of sulphhydryl-groups.
Spektroskopische Untersuchungen an substituierten o -Hydroxystyrylpyryliumperchloraten
Authors: Arnold G.
Published: March 2015

The characteristic infrared absorption frequencies of substituted o-hydroxy-stylryl-naphthopyrylium perchlorates and -benzopyrylium perchlorates ν (C = C), ν (C = O), ν (Cl —O), ν (O — H) and ν (C — OH) and the wavelength of the absorption in the visible region have been measured in dependence of the nature and the position of the substituents in order to determine the structural changes due to the different substitutions. Generally the influence of the substituents is decreasing with increasing of planarity of the entire system.
An Electron Paramagnetic Resonance Study of Mn(II)-Chloro Complex Formation in Ν,Ν-Dimethylformamide
Authors: Bard James R. , Holman Joe T. , Wear James O.
Published: March 2015

EPR spectra differing in hyperfine splitting have been reported for Mn (II) ions in Ν,Ν-Dimethylformamide (DMF) when using Mn (ClO4) 2 and MnCl2. The difference in the reported spectra is shown to be due to the species MnCl4
2⊖ by a mole ratio plot. The presence of MnCl⊕ is also indicated by a mole ratio plot. Three basic spectra, differing in hyperfine splitting, are obtained for solutions of Mn (ClO4) 2 in DMF to which varying amounts of chloride ion have been added. ΔH° for the equilibrium reaction of the species Mn2⊕ und MnCl⊕ was determined from the variation of the formation constant, Kc, with temperature over the range 25° to 116°C. Values for ΔF° and ΔS° at 25°C are also given.
Untersuchungen der kernmagnetischen Resonanz von Phosphorverbindungen XX
Authors: Heckmann Gernot , Fluck Ekkehard
Published: March 2015

Die Kernresonanzlinie von weißem Phosphor wurde in verschiedenen Lösungsmitteln gemessen. Die chemischen Verschiebungen sind konzentrationsabhängig und werden in der Reihenfolge der Lösungsmittel CS2, C6H5NCS, CCl4, C6H6, (C2H5) 2O, C2H5OH deutlich größer. An weißem Phosphor und einer Lösung von weißem Phosphor in CS2 wurde die Temperaturabhängigkeit der chemischen Verschiebung untersucht.
Die Schwingungsspektren von MoO3, WO2Cl2 und WO3 im festen Zustand /Solid State Vibrational Spectra of MoO3, WO2Cl2 and WO3
Authors: Mattes R. , Schröder F.
Published: March 2015

The Raman and infrared spectra of MoO3, WO2Cl2 and WO3 have been measured. The application of the method of factor group analysis leads to the assignment of the observed frequencies to terminal or bridging metal-oxygen bonds. The observed frequencies depend on the length or type (terminal or bridging) of a bond and on the coordination number of the metal atom.
Properties of the Photoactive Chlorophyll-aII in Photosynthesis
Authors: Döring G. , Renger G. , Vater J. , Witt H. T.
Published: March 2015

1. The complete difference spectrum of the reaction of the photoactive chlorophyll-an is presented.

2. The reaction of excited chlorophyll-aII is of the type of a sensitizer. It is not engaged directly in the electron transfers. This is in contrast to the photoactive chlorophyll-aI which is an electron donor in its excited state.

3. The chlorophyll-aII-reaction can be separated from the overall reaction by heating chloroplasts 5 min at 50°C.

4. Chlorophyll-an is the reaction center of the well-known poison DCMU.

5. Properties of chlorophyll-aII are depicted in Tab. 1. They are compared with those of chlorophyll-aI and the O2-evolution system.
Photoaktive Stoffe aus Männchen von Formica polyctena Foerst. (Ins. Hym. Form.)
Authors: Schmidt Gerhard H.
Published: March 2015

In the males of the ant F. polyctena 38 different fluorescentic substances were isolated by paper column chromatography. Nine of them could be identifed as isoxanthopterin, pterin-6-carbonic acid, ʟ-6- (erythro-1,2-dihydroxypropyl) -pterin, D-or-L-6- (threo-1′,2′,3′-trihydroxypropyl) -pterin, lumacine, lumacine-6-carbonic acid, isoxantholumacine, 6-methyl-8-ribityl-isoxantholumacine and riboflavin. Some of these pteridines and also riboflavin were bound in different relations. The isolated compounds are characterised by UV spectra, Rf values, electrophoretic mobility, and some oxidative or reductive reactions. The importance and formation of some photoactive compounds are discussed.
Potentiometric Investigation on the 3,5-Dinitrosalicylic Acid Complex of Mg(II)
Authors: Dube S. S. , Dhindsa S. S.
Published: March 2015

The complexation reaction of magnesium and 3,5-dinitrosalicylic acid has been investigated by potentiometric method in aqueous 0.1 M KNO3 medium. The formation constants (log K) of the complex MgA predominating in the pH range 6 — 9 have been found to be 2.30, 2.425 and 2.65 at 25, 30, and 35°C respectively. The values of overall changes in ΔF, ΔH and ΔS accompanying the reaction have also been evaluated at 30°C and found to be —3.385 kcal/mole, —13.71 kcal/mole and —34.0 cal/degree respectively.
Molecular Constants of PClF4
Authors: Venkateswarlu K. , Girijavallabhan C. P.
Published: March 2015

Potential energy constants of the G.V.F.F. type, generalised mean square amplitudes of vibration, shrinkage effect and Coriolis coupling coefficients of PClF4 molecule are evaluated from spectroscopic data. The results are discussed in relation to the structure of the molecule.
Immunologische Studien am Omentum.
Authors: Krüsmann W. F. , Kasemir H. , Ax W. , Fischer H.
Published: March 2015

An thymektomierten, scheinoperierten und normalen NMRI-Mäusen wurde mit 3H-Thymidin autoradiographisch die Mesothelzell-Proliferation am Omentum majus nach intraperitonealer Stimulierung mit Schaferythrozyten untersucht.

Bei thymektomierten Tieren war die Mesothelproliferation am 1. und 2. Tag nach der Injektion im Vergleich zu scheinoperierten Tieren hochsignifikant vermindert.

Bei normalen Tieren war die Mesothelproliferation nach Sekundärstimulus geringer als nach Primärstimulus. Diese Befunde und ihre Deutung werden diskutiert.
Unterschiedliche biologische Aktivität des Hühnerinsulins an der Maus in vivo und in vitro / The Different Biological Activity of Chicken Insulin in Mice Applied in Vivo and in Vitro
Authors: Schauder Peter , Buck Max Dieter
Published: March 2015

Chicken insulin was tested in mice in vivo and in vitro. The biological activity was compared to bovine insulin (=100%) as follows: 1. In vitro: Fat pad test 375%; 14C incorporation into the lipids of fat pads 369%: hemidiaphragm insulin assay 373 percent. 2. Localized intraperitoneal action in vivo: 14C incorporation into the fat pads 195%: U-14C-glucose incorporation into glycogen of hemidiaphragm 215 per cent. 3. Mouse convulsion test: The activity was slightly increased.
Selektive Anreicherung von Staphylokokken-Panton-Valentine-Leukozidin mit Aluminiumoxid-Cholesterin / Selective Enrichment of Staphylococcus “Panton-Valentine”-Leukocidine with Aluminium Oxide Cholesterol
Authors: Kanoe M. , Blobel H. , Schaeg W.
Published: March 2015

A selective concentration of “Panton-Valentine”-leukozidine (PVL) from the culture-supernatant Staphylococcus aureus was achieved through adsorption of most of the a-hemolysin, coagulase, eggyolk-opacity factor and fibrinolysin to aluminiumoxide cholesterol. PVL was further concentrated through dialysis against a saturated ammonium sulfate solution and subsequent pressure-filtration. Through pressure-filtration relatively low-molecular staphylococcal substances, such as a part of a nuclease, could be separated from PVL.
Polarographic Behaviour of 3-Mercapto-1,2-propanediol at d.m.e.
Authors: Saxena R. S. , Singh Pratap
Published: March 2015

The polarographic behaviour of 3-mercapto-1, 2-propanediol (TSH) at the d.m.e. has been investigated in presence of 0.1 M NaClO4 and 0.001% Triton X-100 with respect to the effects of changes in pH. concentration of TSH, drop time and temperature on the wave characteristics. A single well defined irreversible anodic wave was obtained over the entire pH range (1.84 — 12.3) which was found to shift towards the more negative potential with the increase in pH. The E½ values obtained at different pH were used to evaluate the dissociation constant of sulphydryl group; the pK value has been found to be 9.25.

The linearity of id with TSH concentration provides a rapid and precise method for the determination of TSH to 0.1 mmole. The values of Kinetic parameters-formal rate constant (K°b,h) and transfer coefficient (a) have been evaluated by applying Koutecky’s theoretical treatment as extended by Meites and Israel and were found to be 1.738 × 10-4 cm/sec and 0.277 respectively.
Die Aminosäuresequenz des Ornithin und Lysin enthaltenden Mureins einiger Stämme von Lactobacillus bifidus aus dem Pansen /The amino acid sequence of the ornithine and lysine containing mureins of some strains of Lactobacillus bifidus isolated from rumen
Authors: Holzapfel Wilhelm , Scardovi Vittoria , Kandler Otto
Published: March 2015

Cell walls of six strains of Lactobacillus bifidus (recently classified as Bifidobacterium globosum) isolated from the rumen of sheep were isolated by lysing the cells with glass beads followed by tryptic digestion. No teichoic acid could be found. The polysaccharide consists of galactose, rhamnose and glucosamine. The murein (peptidoglycan) contains MurNAc, GlcNH2NAc, Glu, Ala, and diamino acids in a molar ratio of 1:1:1:5:1. Both diamino acids, lysine and ornithine are present. In two strains they occur in about equal amounts, while in the other four strains ornithine is predominant. The lysis of the cell walls by lysozyme resulted in a mixture of two types of muropeptides: One contains lysine, the other ornithine.

The amino acid sequence was determined by analysing the oligopeptides arising during acid partial hydrolysis. It was shown, that the tetrapeptides attached to the muramic acid are equal to those of other mureins: L-Ala-γ-D-Glu-L-Lys (L-Orn) -D-Ala. Glutamic acid is probably amidated, since the total hydrolysate contained slightly more than one mole of NH3 per mole of glutamic acid. The cross-liking peptide is a tri-alanine, which is bound to the ω-aminogroup of the diamino acid of one tetrapeptid and to the C-terminal D-alanine of another. Since about 2 —4% of the alanine is N-terminal in the cell wall, 10 to 20% of the interpeptide bridges are probably not cross linked. In addition 2 — 3% of the diamino acids are ω-N-terminal and therefore not substituted by a trialanine. A small percentage of D-alanine and of the diamino acids is C-terminal. The latter indicates, that some of the peptide subunits are incomplete i.e.. the terminal D-alanine is missing.
Influence of X-irradiation on enzyme induction: phosphoenolpyruvate carboxykinase in the liver of irradiated mice
Authors: Berndt J. , Brecht I. , Kofler E.
Published: March 2015

Normal or adrenalectomized mice were wohle-body X-irradiated with 690 —4000 R either after hydrocortisone administration or during a 24 h fasting period, and PEP carboxykinase activity measured after the appropriate time. The results show that the induction of PEP carboxykinase is not affected by the irradiation, neither in hormone treated nor in fasting normal or adrenalectomized mice as compared to the controls. These findings support the assumption that the protein synthesizing system in the living cell is very resistant to ionizing radiation.
Regulation glykolytischen Umsatzes durch Synthese und Abbau von Enzymen Regulation of Glycolysis by the Synthesis and Degradation of Enzymes
Authors: Kahl G. , Lange H. , Rosenstock G.
Published: March 2015

Differential derepression of the genome of potato tuber cells causes the onset of a vigorous metabolic activity, which is initiated by rapid synthesis of different RNA species, various proteins and phospholipids. Consequently enhanced respiration and the build up of cell compartments such as ribosomes and mitochondria as well as the performance of cell divisions and suberization of new-formed cell walls occur. Although there is an activation of metabolism in general with a concomitant rise in concentration of most glycolytic metabolites — as was proved for fructose-1.6-diphosphate, dihydroxyacetone, glyceraldehade-3-phosphate, phosphoenolepyruvate and pyruvate — the activities of the corresponding enzymes do not reflect these uniform metabolic changes. Aldolase and in a pronounced manner enolase and glutamate — pyruvate — transaminase lower their activities suddenly after derepression. The activity of triosephosphateisomerase remains constant. In contrast phosphoglyceromutase, pyruvate kinase and to a lower extent malic enzyme enhance their action during the same time.

Without doubt, differential lowering and enhancing the activity of glycolytic chain constituents at the same time is an important regulatory mechanism of the cell. The activation represents de novo synthesis of the protein concerned whereas the inactivation depends largely on protein synthesis. This is clearly shown by experiments with inhibitors of protein synthesis.

It is proposed that this differential synthesis and degradation represent a “long-time-regulation” of enzymatic activity of the cell in contrast to the known “short-time-regulation” by feedback or competition.
Ferredoxin als Kofaktor der cyclischen Photophosphorylierung in einem zellfreien System aus der Blaualge Anacystis nidulans
Authors: Bothe Hermann
Published: March 2015

The properties of the ferredoxin-catalysed cyclic photophosphorylation in lyophilised and lysozyme treated Anacystis nidulans with rates up to 80 μmoles ATP/h/mg chlorophyll are described. The concentration of ferredoxin needed for the saturation of the ferredoxin-catalysed cyclic photophosphorylation is about 6 — 8 times higher than for NADP-reduction. In contrast to the ferredoxin-catalysed cyclic photophosphorylation in spinach chloroplasts the reaction in Anacystis is relatively intensive to the “poising“ of the system and is not affected by antimycin A. Whilst under aerobic conditions in broken chloroplasts ferredoxin catalyses a pseudocyclic photophosphorylation in which H2O2 is a component, in Anacystis on addition of ferredoxin ATP is only formed on the cyclic pathway even in air. In chloroplasts as well as in Anacystis disulfo-disalicylidenpropandiamin (DSPD) inhibits only the ferredoxin-catalysed cyclic photophosphorylations and the NADP-reductions, but not the ferredoxin stimulated ATP-formations under aerobic conditions. Evidence is presented once more that ferredoxin is the cofactor of cyclic photophosphorylation in vivo.
The Integumentary Mucous Secretions of the Earth Worm Megascolex mauritii
Authors: Krishnan N. , Rajulu G. Sundara
Published: March 2015

A histochemical study of the epidermal gland secretions in earth worm Megascolex mauritii has been made. The secretions of the aluminous gland is a glyco or mucoprotein and that of the mucous gland cells is an acid mucopolysaccharide. Two types of mucous glands are present in the epidermis, the small and large mucous glands, secreting hyaluronic acid and highly acidic sulphated mucopolysaccharide, respectively.

The functions of the secretions from these glands are investigated. The albuminous and small gland cells secrete mucin under normal conditions and this mucin keeps the body surface moist and serves as lubricant during locomotion. The large mucous gland secretes only after irritation and its secretion may be an alarm pheromone.
Infrared Spectra of Some Trivalent Earth Metal Cupferrone Complexes
Authors: Abou El Ela A. H. , Afifi H. H.
Published: March 2015

The IR absorption spectra of the ammonium salt of cupferrone and aluminium, scandium, yttrium and lanthanum trivalent cupferrate complexes are investigated. The IR absorption bands identified in the region 400-4000 cm-1 are given and assigned. It is shown that on complex formation NO stretching frequencies are lowered and new absorption bands are observed and assigned to the M-O band.
Über die Tellurite der Alkalimetalle vom Typ M2TeO3
1
Authors: Thümmel Hans-Jürgen , Hoppe Rudolf
Published: March 2015

Single crystals of M2TeO3 (M = Li, Na, K, Rb, Cs) have been investigated by X-ray diffraction. All compounds crystallize monoclinic. K2TeO3, Rb2TeO3 and Cs2TeO3 are isotypic
Phosphinimino-phosphoniumchloride mit P-P(P-As)-Bindung / Phosphinimino-phosphonium Chlorides with P-P(P-As) Bonds
Authors: Wolfsberger Werner
Published: March 2015

Desilylation reactions of N-trimethylsilyl-triorganophosphine imines with diorganochlorophosphines do not afford phosphinimino-phosphines, because a second mole of diorganochlorophosphine is immediately added yielding phosphinimino-phosphonium chlorides containing a phosporus-phosphorus bond. These phosphonium chlorides can also be obtained from phosphinimino-phosphines and diorganochlorophosphines. The latter route has been extended to prepare analogous compounds with a phosphorusarsenic bond. All new compounds were characterized by elemental analysis, and by IR 1H and 31P NMR spectra.
Ein statistisches Modell der Ladungsverteilung in quellungsfähigen glimmerartigen Schichtsilicaten mit beidellitischer Ladungsverteilung / A Statistical Model of the Charge Distribution in Beidellitic and Swelling Mica-Type Layer Silicates
Authors: Schön Günter , Weiss Armin
Published: March 2015

The charge distribution in mica-type layer silicates, which are capable of intercrystalline swelling, is discussed on the basis of a statistical model. The model explains the distribution of exchangeable cations and water molecules onto the geometrically identical lattice sites and simplifies the calculation of the electrostatic interaction energy between adjacent layers.
Über Alkali-Oxofluorometallate der Übergangsmetalle, V1-4
Authors: Pausewang Gerhardt
Published: March 2015

Oxidfluorides A2WO2F4 (A = Rb,Cs) and Cs2TaOF5 were prepared and investigated by X-rays. All of the compounds crystallize hexogonally (K2GeF6-type).
Ein neuartiger Syntheseweg für (π-C5H5Cr(CO)3)2SnX2-Komplexe / A Novel Synthesis of (π-C5H5Cr(CO)3)2SnX2 Complexes
Authors: Kruck Thomas , Breuer Herbert , Becker Franz-Josef
Published: March 2015

It is shown that reactions of tin(II) halides, SnX2 (X = Cl, Br), with the [π-C5Η5Cr-(CO)3]— anion in acetone yield (π-C5Η5Cr(CO)3)2SnX2 complexes. The compounds are characterised by their IR and mass spectra.
IR-spektroskopische Untersuchungen über die Wechselwirkung von Alkinen mit Aluminiumbromid / Infrared-spectroscopical Investigation on the Interaction of Alkines with AlBr3
Authors: Perkampus H.-H. , Weiss W.
Published: March 2015

The interaction of alkines with AlBr3 was investigated by IR-spectroscopic methods. These investigations revealed that layers of pentin-1 and hexin-1 polimerized under the influence of AlBr3 at about 170°K. Pentin-2, hexin-2 and hexin-3 however, showed new bands around 2200 cm-1 as the consequence of an interaction of these alines with AlBr3; after annealing at 170°K these measurements were performed at 77°K, since these complexes are not stable at elevated temperatures (~220°K).
Heteronuclear Spin-Spin Coupling Constants Between Directly Bonded Atoms as a Probe of Configuration at Phosphorus Atom Involved in Diastereoisomeric 4-Methyl-1,3,2-dioxaphosphorinans
Authors: Stec W. J.
Published: March 2015

The 1JPH and 1Jpse absolute values showed a clear dependence on the orientation of the substituents at 2-P in several pairs of substituted diastereoisomeric 2-X-2-Y-1,3,2-dioxaphosphorinans (X = H, Se, SeR; Y=O, S, OR) and may therefore provide information about conformation and configuration at phosphorus atom.
Darstellung einiger Salze des Schwefeloxiddifluoridimids und deren Reaktion mit Dimethylzinndihalogeniden / Preparation and Properties of Some Sulfuroxidedifluorideimide Salts and their Reaction with Dimethyltindihalides
Authors: Feser Manfred , Höfer Rainer , Glemser Oskar
Published: March 2015

HNSOF2 reacts with metal carbonates to form the salts Li+NSOF2
-, Cs+NSOF2- and Ag+NSOF2. The reaction of Ag+NSOF2
- with halides yields the new dimethyltin compounds (CH3)2SnClNSOF2, (CH3)2SnBrNSOF2 and (CH3)2Sn(NSOF2)2. The IR spectra of the sulfuroxidedifluorideimide salts are compared with the isoelectronic SO2F2. All compounds are characterized by analysis, IR, NMR and mass spectra.
Diborylselenane, R2B—Sen—BR2 / Diborylselenanes, R2B—Sen—BR2
Authors: Riegel Friedrich , Siebert Walter
Published: March 2015

Dimethyltinselenid reacts with diorganyliodoboranes to give R2B—Se—BR2. The compounds with R = C6H11 and C6H5 are stable, whereas with R = CH3 and C4H9 decomposition to polymeric (RBSe)n was observed. Diboryldiselenanes have been obtained from (C5H5)2TiSe5 and R2B—I as well as from borolane and elemental selenium. At higher temperature these diboryldiselenanes decompose to form triselenadiborolanes and trialkylboranes.
Formation of Radical Intermediates in Sulphur Dioxide Solutions of Tertiary Aliphatic Amines
Authors: Donbavand M. H. , Möckel H. J.
Published: March 2015

The addition of molecular iodine to solutions of tertiary aliphatic amines in liquid sulphur dioxide is found to result in the formation of stable free radical oxidation intermediates. In triethylamine solutions, oxidised under these conditions, aromatisation appears to take place to produce a pyridinyl radical. Radicals formed from N-ethyldimethylamine, Ν,Ν-diethylmethylamine and tri-n-propylamine on the other hand appear to be essentially aliphatic in character, with two of the N-alkyl groups intact. The magnitude of the measured coupling constants however, implies some delocalisation in the “damaged” alkyl group, possibly via a tautomeric mechanism. A number of mechanistic possibilities are explored to account for the roles played by iodine and sulphur dioxide in these reactions.