bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclic AMP Is Not Involved as a Second Messenger in the Response of Soybean to Infection by Phytophthora megasperma f. sp. glycinea
Authors: Hahn Michael G. , Grisebach Hans
Published: August 2018

cAMP levels were monitored in soybean (Glycine max) infected with race 1 of Phytophthora megasperma f. sp. glycinea and in soybean cell suspension cultures treated with a glucan elicitor from P. megasperma. While cAMP could be readily detected in soybean hypocotyls using a radio ­ immunoassay, no correlation was observed between infection and cAMP levels. No cAMP was detected in suspension cultured soybean cells. These results suggest that cAMP does not play a significant role in the plant's response to fungal attack, or the response of suspension cultured cells to elicitor.
Caffeine-Induced Surface Blebbing and Budding in the Acellular Slime Mold Physarum polycephalum
Authors: Kukulies J. , Stockem W. , Wohlfarth-Bottermann K. E.
Published: August 2018

The mechanism of plasma membrane proliferation was studied in the acellular slime mold Physarum polycephalum with the aid of light and electron microscopical techniques. Treatment of protoplasmic drops with a Tris-buffered 15 mᴍ caffeine solution causes surface blebbing and budding over periods of 5-90 min. The process of surface blebbing is coupled to a 5-10-fold increase of the surface area in conjunction with characteristic changes in cytoplasmic morphol­ogy. Successive constriction of blebs exhibiting different sizes and degree of hyalo-granuloptasmic separation leads to the formation of numerous spherical caffeine droplets. During the process of surface budding and droplet formation the total surface area of the original (genuine) protoplasmic drop is not reduced, but continues to grow.

Freeze-etch studies show that caffeine concomitantly causes characteristic changes in the fine structure of the plasma membrane. During the initial phase of surface blebbing the original density of intramembranous particles (IMP) is reduced from 3676/μm2 to 1669/μm2 and the PF:EF ratio (IMP/μm2 protoplasmic face: exoplasmic face) shifts from 2.4:1 to 2.8:1. When surface budding is completed the IMP-density in the plasma membrane of single caffeine droplets increases again to 2289/μm2 and the PF:EF ratio changes to 1.5:1. Simultaneously, the isolated caffeine droplets produce numerous small hyaline membrane protrusions, which are pinched off and contain no IMP. Control experiments demonstrate that Tris-buffer without caffeine also shows a weak capacity to induce surface blebbing, to change the IMP-density and the PF:EF ratio (2443/μm2; 1.5:1); but Tris-buffer fails to cause surface budding. On the other hand, different concentrations of sucrose (25-200 mᴍ) can supress to a certain degree both caffeine- and Tris-buffer-induced surface blebbing, but not caffeine-dependent surface budding.

The caffeine-effect is reversible insofar as protoplasmic drops with blebbing and budding activity recover to normal morphology, fine structure and locomotion when transferred to physiological conditions.

The mechanisms of successive changes in plasma membrane morphology as well as the mode of a participation of the actomyosin system in cell surface dynamics are discussed.
Energy Parameters, Macromolecular Synthesis and Cell Cycle Progression of in vitro Grown Ehrlich Ascites Tumor Cells after Inhibition of Oxydative ATP Synthesis by Oligomycin
Authors: Kroll Werner , Loffler Monika , Schneider Friedhelm
Published: August 2018

1.In order to elucidate the significance of oxidative ATP production for the proliferation of Ehrlich ascites tumor cells, cell cycle progression, energy metabolism and macromolecular synthesis in the presence of oligomycin were studied.

2.In the presence of the inhibitor (20 μ/ml), lactate production and glucose uptake of the cells increased by about 30-35% as compared to controls; oxygen consumption was maximally inhibited by 30-45% and could not further be reduced by higher concentrations of the inhibitor. ATP/ADP ratios of the oligomycin treated cells and control cells were not significantly different.

3.In the first passage in the presence of oligomycin proliferation of the cells is reduced to about 50% that of controls; without severely affecting viability (dye exclusion test). In the second passage with oligomycin cell proliferation completely arrests. As was shown by flow cytometric analysis and BrdU-H33258 technique of flow cytometry, cells accumulate in the early S phase; division of cells which are in the S- and G 2 M compartment at the beginning of oligomycin treatment accounts for the increase of cell number in the first passage in the presence of oligomycin. On recultivation in the third passage in the absence of the inhibitor cells take up proliferation again; an increase of cell number of about 60% of controls was observed within 24 h.

4.In the presence of oligomycin incorporation of [2-l4C]thymidine is reduced to about 20% of the controls within 8 h. incorporation of [U-l4C]lysine begins to slow down immediately after treatment with the inhibitor, the same is true for the incorporation of [2-14C]uridine. Transport of α-aminoisobutyric acid into the cells is not severely affected.

5.It is suggested, that not lack of energy by inhibition of oxidative phosphorylation accounts for the arrest of cell cycle progression in the presence of oligomycin but rather the blockade of transport of cytoplasmatic (glycolytic) ATP into mitochondria, which is caused by the high potential built up across the mitochondrial membrane in the presence of this inhibitor.
Synthesis and Biological Evaluation of 7α,7α,7α,8α,8α,8α- Hexafluororiboflavin and 7α,7α,7α,8α,8α,8α-Hexafluoro-FMN
Authors: Nielsen Peter , Bacher Adelbert , Darling Diana , Cushman Mark
Published: August 2018

7α,7α,7α,8α,8α,8α-Hexafluororiboflavin (4) has been prepared and its oxidation-reduction potential determined polarographically to be + 0.02 V with respect to the standard hydrogen electrode. Compound 4 does not by itself promote the growth of Lactobacillus casei. However, in the presence of low riboflavin (1) concentrations, the hexafluoro analog 4 has some growth enhancing activity. The FMN analog 7α,7α,7α,8α,8α,8α-hexafluororiboflavin 5′-phosphate (10) was also synthesized and found to bind tightly to apoflavodoxin from Megasphaera elsdenii. The dissociation constant (3.2 × 10-9m) is about one order of magnitude larger than that of FMN (1.1 × 10-10м). However, apoflavodoxin reconstituted with hexafluororiboflavin 5′-phosphate (10) has no coenzyme activity. Hexafluoro-FMN (10) was also unable to act as a coenzyme for luciferase from Photobacterium fisheri. Hexafluororiboflavin 4 did not inhibit the light riboflavin synthase from Bacillus subtilis to a significant extent {Ki> 10-4 м).
Transient Activation of the Ca2+-ATPase from Sarcoplasmic Reticulum during Thiol Modification by 5 ,5′-Dithiobis(2-nitrobenzoate)
Authors: Swoboda Gertrude , Hasselbach Wilhelm
Published: August 2018

In the reaction of sarcoplasmic reticulum m em branes with excess 5,5′-dithiobis(2-nitrobenzoate) (DTNB) some new features were observed:

1) The Ca2+-dependent ATPase activities of increasingly modified preparations were considerably enhanced during the initial stage of thiol blockage. A maximum (130 -160% of the control activity) was reached when about 1.5 - 2 mol thiol groups per 105 g vesicular protein had reacted, in the absence of ATP and detergent. At higher extents of modification inactivation occurred. Purified ATPase behaved principally similar to native sarcoplasmic vesicles.

2) In the presence of Mg2+ and ATP the activity maxim um (up to 180% of control) was broadened and shifted towards a higher degree of thiol blockage. Concomitantly the modification and inactivation rates were considerably reduced.

3) Glycerol (10 -30 % , v/v) slightly enhanced the ATPase activity maximum and reduced the rate of inactivation essentially only by decreasing the DTNB modification rate.

4) In the presence of sufficient myristoylglycerophosphocholine for solubilization no activation was observed.

5) The steady state level of phosphoprotein from ATP was raised to about 150% of the control level 10 s after addition of DTNB (about 1/2 thiol blocked), followed by a linear decrease with the number of thiols labeled, while the Ca2+-dependent ATPase activity of preparations modified under equivalent conditions (10-4 м Ca2+ and 2 x 10-3 м Mg2+ present) showed a broader maximum corresponding to 1.5 thiols blocked.
Phosphorylation of Ca-ATPase of Sarcoplasmic Reticulum with Different Substrates
Authors: Barrabin Hector , Meis Leopoldo de
Published: August 2018

ATP and GTP as substrate for phosphorylation of sarcoplasmic reticulum ATPase are compared. Maximal levels of phosphoenzyme are between 4.5 and 4.8 nmol per mg of protein when either substrate is used provided that phosphoenzyme hydrolysis are strongly inhibited by high calcium concentration (20 mм) and low temperatures ( 0 ° C ) . The maximal values obtained with GTP are lower than those previously reported.

It is shown that this difference is due to underestimation of the specific activity of labeled nucleotides used in previous studies, as revealed by UV absorption and HPLC analysis.

The dependence of the phosphoenzyme levels on calcium concentration, pH and temperature confirm previous findings indicating that ATP, but no GTP, accelerates the rate limiting step of the catalytic cycle.
Notizen: Interaction of Ascorbic Acid with Disulfides
Authors: Fleming James E. , Bensch Klaus G. , Schreiber Jörg , Lohmann Wolfgang
Published: August 2018

Electron spin resonance (EPR) spectra demonstrate the formation of a complex between the ascorbate ion and disulfides such as oxidized glutathione, cystine, gamma globulin, bovine serum albumin, 4-4′ dithiopyridine, and dithiobutyric acid. However, except in the case of 4-4′ dithiopyridine. ascorbic acid (AH2) is not capable of reducing the disulfide bond in these compounds. These results can be explained in terms of the redox potential of ascorbic acid and its radical semidehydroascorbic acid (SDA). These compounds can reduce the S-S bond of 4-4′ dithiopyridine, the redox potential of which is E′ = -0. 1 V and, thus, more positive than the ones deter­mined for the ascorbic acid system.
Notizen: Supplementary Data on the Sex Attractant System of Panolis flammea
Authors: Priesner Ernst , Schroth Martin
Published: August 2018

Pheromonal synergism and inhibition in P. flammea was further studied through electrophysiological and field trapping tests. Z11-tetradecenyl acetate and Z11-hexa - decenyl acetate, each acting upon a separate type of male sensory cell, were equally effective in synergizing attraction responses to the major pheromone component, Z9-tetradecenyl acetate. Addition of Z7-dodecenyl acetate to these lures reduced captures. Male attraction specificity markedly varied with local moth density.
Determination of Measles Virus Protein Molecular Weights on High Percentage, Highly Cross-Linked SDS Polyacrylamide Gels
Authors: Carter M. J. , Baczko K.
Published: August 2018

A recent examination of measles virus mRNA molecules has shown that the nucleocapsid and haemagglutin messengers are of the size expected from a consideration of their protein products. How ever, the mRNA for membrane protein is approximately 50% larger than the size required. The molecular weight of matrix protein has been determined by SDS-polyacrylamide gel electrophoresis, and this procedure can lead to an underestimation of the true size of hydrophobic molecules which show increased SDS binding. It is therefore appropriate to examine the molecular weight determination of this protein to exclude such an artefactual discrepancy in mRNA and protein sizes. We report here that measles virus membrane protein does not shown such anomalous behaviour and confirm that the size discrepancy is a true phenomenon.
Interference by Herbicidal Inhibitors of Electron Transport with Phosphorylation and Permeability Properties of Chloroplast Membranes
Authors: Moreland Donald E. , Novitzky William P.
Published: August 2018

Many herbicides inhibit chloroplast electron transport by interfering with a proteinaceous component of the Qв complex located in the appressed granal membrane. Certain of these herbicides, designated inhibitory uncouplers, also interfere with photophosphorylation and affect other chloroplast-mediated responses, some of which involve components located in the nonappressed granal membrane. The inhibitory uncouplers can be divided into dinoseb (phenolic) types which contain dissociable protons and dicryl (acylanilide) types which are nonionic. The dinoseb types can function as protonophores and shuttle protons across the thylakoid membrane at low concentrations and can alter the integrity of semipermeable membranes at higher concentrations. However, the dicryl types only alter the integrity of the membranes. The inhibitory uncouplers, but not the DCMU-types of electron transport inhibitors: stimulated electron trans- port from DPIPH2 to methyl viologen; inhibited valifiomycin-induced swelling of intact chloroplasts; increased the permeability of the chloroplast envelope to K+ in the absence of an ionophore; prevented energization of the thylakoid membrane by PS I; and increased the permeability of phosphatidyl choline liposomes to protons. Chlorination response patterns obtained with isomers of N-phenyl-2-methylpentanamides in the above reactions, in general, were similar for interference with the Qв complex, i.e., in all assays, dichlorination in the 3,4 or 3,5 positions was associated with maximum inhibitory potency, whereas substitution in an ortho position decreased inhibitory activity. With a series of 1-alkyl-3-(α,α,α-trifluoro-m-tolyl)ureas, maximum inhibition of electron transport was obtained with the butyl derivative, whereas maximum responses for uncoupling and membrane disturbances were obtained with the hexyl or octyl derivatives. Some of the interferences produced by inhibitory uncouplers may result from interactions with the lipoidal components of chloroplast membranes.
Photosynthetic Electron Transport Inhibitors: Some Problems Related to an Accurate Determination of the Molecular Site of Action
Authors: Assche C. J. van
Published: August 2018

When DCMU and DCMU-type inhibitor concentrations vary over a large range, different effects may be observed on chlorophyll fluorescence parameters such as fluorescence transients, areas over fluorescence induction curves as well as kinetics of area accumulation. These results would indicate a heterogeneity of PS II electron acceptors, or an inhibitor partitioning behavior dependent on the concentration. Also, a threshold value can be reached at supra-optimal concentrations, beyond which the back reaction is almost completely blocked. Such an approach makes it possible to find out inconsistencies in the results, brought about by dual effects of some inhibitors such as phenol-type herbicides, as previously proposed.
The Effects of 3-(3,4-Dichlorophenyl)-1,1-dimethylurea on the Photosynthetic Oxygen Complex
Authors: Delrieu Marie-José
Published: August 2018

In the presence of trypsin and ferricyanide as external electron acceptor, lettuce chloroplasts are resistant to DCMU, showing that the inhibitory site of DCMU is only situated on the acceptor side of photosystem II. However, kinetic properties of the oxygen evolving complex are modified at non-saturating concentrations of DCMU. These changes are interpreted in terms of a model with two distinct charges separation systems on the same center: the auxiliary donor- acceptor system DQL implicated in the transitions S1 → S2 and S2 → S3 would be much less affected by DCMU than the main donor-acceptor system YQH after the first flash.
Comparison of Diuron-and Phenol-Type Inhibitors: Additional Inhibitory Action at the Photosystem II Donor Site
Authors: Pfister Klaus , Schreiber Ulrich
Published: August 2018

Inhibitors of photosystem II reactions from the “diuron-type” and “phenol-type” have been compared regarding their mechanism of action.

“Diuron-” as well as “phenol-type” inhibitors act at the acceptor site of photosystem II by displacing the secondary acceptor quinone Qв from its binding site.

“Phenol-type” inhibitors additionally interfere with the donor site, which is demonstrated in studies of chlorophyll fluorescence and luminescence. This mechanism of action is shown to be similar but not identical to that reported for hydroxylamine.
Protein Sequence Homologies between Portions of the L and M Subunits of Reaction Centers of Rhodopseudomonas capsulata and the Qв-Protein of Chloroplast Thylakoid Membranes: a Proposed Relation to Quinone-Binding Sites
Authors: Hearst John E. , Sauer Kenneth
Published: August 2018

Sequence homology has been found between the L and M subunits of Rhodopseudomonas capsulata reaction centers and the Qв-protein from all species thus far sequenced. The homology between the L subunit and the Qв-protein is contained in the sequence PFHMLG---F----AMHG-LV-S and is believed to have survived three billion years of evolution. A model is presented which associates quinone binding with this highly conserved sequence.
Comparison of the Photosynthetic Capacity between Intact Leaves of Triazine-Resistant and -Susceptible Biotypes of Six Weed Species
Authors: Oorschot J.L.P. van , Leeuwen P.H. van
Published: August 2018

The rate of photosynthesis in intact leaves of a triazine-resistant biotype of Amaranthus retroflexus was about 15% lower than that of a triazine-susceptible biotype. Differences in photosynthesis between resistant and susceptible biotypes of Polygonum lapathifolium, Poa annua and Solanum nigrum were not significant, and absent in Chenopodium album and Stellaria media. The results are brought in relation to the appearance of resistant biotypes in the field.
The Structure of Desmocarpin, a Pterocarpan Phytoalexin from Desmodium gangeticum
Authors: Ingham John L. , Dewick Paul M.
Published: August 2018

Ethyl acetate extracts of diffusates from the fungus-inoculated leaflets of Desmodium gangeticum have been found to contain six isoflavonoid phytoalexins including the isoflavones genistein and 2′-hydroxygenistein, and the isoflavanones dalbergioidin, diphysolone and kievitone. These known phytoalexins occur together with a new antifungal isoflavonoid (desmocarpin) for which the structure (-)-(6aR; 11aR)-1,9-dihydroxy-3-methoxypterocarpan is proposed.
New Dextrorotatory Pterocarpan Phytoalexins from Leaflets of Nissolia fruticosa
Authors: Ingham John L.
Published: August 2018

Three isoflavonoid phytoalexins produced by the fungus or CuSO4-treated leaflets of Nissolia fruticosa have been identified as (+)-6aS; 1 la S-3.7-dihydroxy-9-methoxypterocarpan (nissicarpin). (+)-6 aS ; 1 la S-7-hydroxy-3,9-dimethoxypterocarpan (fruticarp in) and (+)-6a.S; 11 aS-3,7-dihydroxy-2,9-dimethoxypterocarpan (nissolicarpin).
Elaboration of the 6,7,8 Oxygenation Pattern in Simple Coumarins: Biosynthesis of Puberulin in Agathosma puberula Fourc
Authors: Brown Stewart A. , Rivett D. E. A. , Thompson H. Joan
Published: August 2018

Umbelliferone and scopoletin are well utilized as precursors of puberulin, a 7-O-prenyl ether of isofraxidin elaborated by Agathosm a puberula Fourc. (Rutaceae). As ferulic, sinapic, and caffeic acids were all more poorly utilized than 4′-hydroxycinnamic (p-coumaric) acid, the partial biosynthetic route: 4′-hydroxycinnamic acid →→ um belliferone → aesculetin → scopoletin →→ puberulin is suggested as the major pathway. Prenylether formation apparently occurs at or beyond the scopoletin stage. The implication that ferulic acid does not participate in the formation of scopoletin from 4′-hydroxycinnamic acid is at variance with the known role of ferulic acid as a scopoletin precursor in tobacco.
Identification of N1–Glycolylbiuret in the Gamma Radiolysis of Aerated Aqueous Solution of Cytosine. Influence of the pH
Authors: Polverelli Michel , Ulrich Jacques , Teoule Robert
Published: August 2018

N1 Glycolylbiuret, pH-Effect N1 glycolylbiuret has been identified as a radiation product of cytosine in aerated aqueous solution at pH 4.5. When varying the pH of the solution before irradiation from acidic values towards neutral ones. G value of N1 glycolylbiuret reached a maximum at pH 4.5.
Effects of N-Aryl-N’ ,N’ -Dialkyl-1,2-Ethanediainines on ATP Formation in Chloroplasts. QSAR of Amine Uncouplers
Authors: Berg Gerard van den , Brandse Marjo
Published: August 2018

The effects of the algicide PH 40-62 on photosynthetic reactions in spinach chloroplasts were studied. The compound proved to be an uncoupler of photophosphorylation, whereas inhibition of photosynthetic electron transport occurred at higher concentrations. The site of this inhibition was before photosystem II. The uncoupling effect was partially reversible. In a series of related compounds the uncoupling activity appeared mainly dependent on the lipophilic properties of the compounds but electronic effects also played a distinct role. Comparing these uncoupling data with those of some known series of uncouplers it appeared that lipophilicity determines the uncoupling activity in an identical way and a regression equation was found describing the uncoupling activities of 60 compounds belonging to four chemically different groups of com pounds.
The Life Span and Osmotic Fragility of Erythrocytes in Mice Bearing Benzo(a) Pvrene — Induced Fibrosarcoma
Authors: Ray M. R. , Chowdhury J. Roy
Published: August 2018

Erythrocyte Survival. Osmotic Fragility, Fibrosarcom a Red cell survival studies in mice with benzo(a) pyrene [B(a)p]-induced fibrosarcoma indicate marked reduction in RBC 51Cr rW2. In contrast, the t w2 of erythrocytes from B(a)p injected but tumor-free mice was not declined. Increasing tumor burden resulted in increment in the severity of this disorder, and preincubation of normal red cells with tumor supernatant caused significant reduction (p < 0.05) in 51Cr t > /2 . It is suggested that the observed alteration in RBC life span may be due to the effect of tumor. Apparently, both intrinsic and extrinsic cellular defects could be implicated for this abnormality. However, the shortened survival cannot be attributed to altered osmotic fragility, since the erythrocytes of the fibro-sarcomatous mice were more resistant to hypotonic hemolysis in vitro.
Isolation of the Products Resulting from the Reaction of cis and trans Diaminedichloroplatinum [II] with DNA and Chromatin on the Dowex 50 W Column
Authors: Olinski Ryszard , Walter Zofia
Published: August 2018

The production of platinated derivatives of nucleic acid bases resulting from the reaction of cis and trans DDP with DNA and chrom atin was studied.

Bifunctional complex of guanine appeared to be the major product of the interaction of cis isomer with both DNA and chromatin, although other bifunctional adducts of A-Pt-G and A-Pt-A were also isolated. The main product of the interaction of trans DDP with DNA was a monofunctional adduct of guanine. Small amounts of the bifunctional complexes were also isolated. When ssDNA was incubated with trans DDP more bifunctional complexes appeared, what suggests that geometric constrains of double helix prevent formation of these complexes. Trans isomer reacts more easily with chromosomal proteins than cis DDP does. Therefore after the reaction of trans DDP with chromatin less platination occurs on DNA moieties.
Red-Light Effects Sensitized by Methylene Blue on Nitrate Reductase from Spinach (Spinacia oleracea L.) Leaves
Authors: Mauriño S. G. , Vargas M. A. , Aparicio P. J. , Maldonado J. M.
Published: August 2018

Nitrate reductase from spinach (Spinacia oleracea L.) leaves, which had been inactivated in vitro by incubation with NADH and cyanide, was fully reactivated in minutes when irradiated in anaerobic conditions with red light in the presence of methylene blue. Both the rate and the extent of reactivation increased with light intensity (6 to 100 W·m-2) and dye concentration (1 to 10 μM). On the contrary, photoreactivation was completely abolished when NADH or ethylenediaminetetra-acetic acid were present during irradiation. We propose that methylene blue, when photo excited, exhibits a redox potential positive enough to reoxidise the CN--re-duced molybdenum complex settled in the inactive enzyme, thus causing its reactivation.

On the other hand, prolonged irradiation of nitrate reductase, under air and in the presence of methylene blue, promoted an oxygen-dependent irreversible inactivation of the two partial activities of the enzyme. This inactivation was markedly enhanced in 77% deuterated water and greatly prevented by azide, which indicates that singlet oxygen is the species primarily involved in the photooxidative inactivation of the enzyme.
Flash Photolysis of Liposomes Containing Chlorophyll and Zeaxanthin, as a Function of Temperature (2 °-34 °C)
Authors: Brody Seymour Steven
Published: August 2018

The transfer of triplet excitation from chlorophyll to zeaxanthin in liposomes is a function of temperature and pigment concentration.

At 525 nm both chlorophyll and zeaxanthin triplet states are observed. The result is a biphasic increase in absorption. The rise time of absorption by the chlorophyll triplet is much faster, than by the zeaxanthin triplet. With increasing temperature the contribution of absorption by zea­xanthin (relative to that of chlorophyll) at 525 nm increases, and its rise time gets faster. At high ratios of zeaxanthin to chlorophyll, temperature has less effect on both the rise time and absorption by the zeaxanthin triplet state.

The chlorophyll triplet is measured at 780 nm. It decays faster with increasing temperature and or increasing ratio of zeaxanthin to chlorophyll.

The results are interpreted in terms of: increasing fluidity of the lipid liposome with temper­ature, formation of zeaxanthin-chlorophyll complexes at high ratios of zeaxanthin and chloro­phyll, presence of different lipid phases in the liposome bilayer.
Flavonoids of Ericameria laricifolia (Asteraceae)
Authors: Clark W. Dennis , Wollenweber Eckhard
Published: August 2018

Nineteen flavonoid aglycones have been identified from the external stem and leaf resin of Ericameria laricifolia by thin layer co-chromatography with authentic samples. Kaempferol, quercetin, apigenin, and their methyl ethers have been found, along with luteolin and 6-methoxy luteolin. It is suggested that future flavonoid chemosys-tematic studied of resin-exuding species would best focus on aglycones as opposed to glycosides.
Glutamate Dehydrogenase of Pisum sativum: Heat-Dependent Interconversion of the Multiple Forms
Authors: Ehmke Adelheid , Scheid Heinz-Walter , Hartmann Thomas
Published: August 2018

Purified NAD-dependent glutamate dehydrogenase (EC 1.4.1.2) from pea seeds shows a pattern of seven catalytically active molecular forms. The individual forms display different heat stabilities. During incubation at 70 to 75 °C in the presence of protective agents (NADH, Ca2+, DTE) the more heat labile forms are converted into the most stable form. This result presents direct evidence that the multiple forms of pea glutamate dehydrogenase represent conform ational variants of a single protein species
The Composition of Terpene Hydrocarbons in the Essential Oils from Leaves of Four Cistus Species
Authors: Gülz Paul-Gerhard , Kobold Uwe , Michaelis Karl , Vostrowsky Otto
Published: August 2018

The hydrocarbon fractions of the essential oils from leaves of Cistus ladanifer, C. palhinhae, C. laurifolius and C. monspeliensis were analysed by GLC and GCMS techniques.
Novel Epicuticular Leaf Flavonoids from Kalmia and Gaidtheria (Ericaceae)
Authors: Wollenweber Eckhard , Kohorst Gisela
Published: August 2018

Leaves of a number of Ericaceous plants have a thin epicuticular layer that consists mostly of triterpenes. In Kalmia angustifolia, K. latifolia and K. polifolia as well as in Gaultheria procumbens and G. shallon this material also contains trace amounts of flavonoid aglycones. In Kalmia they are the 3-OMe-derivatives of four C-methyl flavones reported previously as the typical leaf-wax flavonoids of Eucalyptus. The new compounds, 5-OH-3,7,4′-triOMe-6,8-diCH3-flavone (kalmiatin), 5-OH-3,7,4′-triOMe-6-CH3-flavone (8-desmethyl-kalmiatin), 5,4′-diOH-3,7-diOMe-6,8-diCH3-flavone (latifolin) and 5,4′-diOH-3,7-diOMe-6-CH3-flavone (8-desmethyl-latifolin) are novel natural products. They could not be detected in eight species of Eucalyptus. A screening of 15 species of Ericaceae revealed that 8-desmethyl-sideroxylin and 8-desmethyl-latifolin are present also in the epicuticular layer on leaves of Gaultheria procumbens, while on G. shallon and on Andromeda polifolia traces of galangin-3-methyl ether were found. In the other species checked no external flavonoid aglycones could be detected.
Die Entladung der Haptocysten von Ephelota gemmipara (Suctoria, Ciliata) / Mode of Discharge of Haptocysts in Ephelota gemmipara (Suctoria, Ciliata)
Authors: Benwitz Gertrud
Published: August 2018

The fine structure of haptocysts, characteristic organelles of most suctorians, is described during the resting state and the discharge after contact with the prey. In Ephelota, there is no fusion of the plasma membranes of predator and prey, as has been suggested for the haptocysts of other suctorians. But the membrane covering the organelle becomes continuous with the plasma membrane of the suctorian tentacle, and inner structures of the haptocyst attach to the perforated pellicle of the prey.
Das radialpolare Differenzierungsmuster bei Trichoplax adhaerens F. E. Schulze (Placozoa) / The Radial Polar Pattern of Differentiation in Trichoplax adhaerens F. E. Schulze (Placozoa)
Authors: Schwartz Viktor
Published: August 2018

In contrast with the outmost uniform aspect of Trichoplax there is a clear cut differentiation between marginal and central cell territories. Dissection and transplantation as well as vital staining show that the marginal material is restricted to a seam approximately 20 μm in width, surrounding the much larger mass of central cells. Isolated marginal or central cell material can not regenerate a complete individual and is therefore doomed to die. Regeneration requires the presence of both components because the cells propagate true to type only, meeting the Ruthmann model (A Ruthmann, Cytobiol. 15, 58 (1977)). There is no redifferentiation between marginal and central cells. Marginal pieces transplanted into the central area produce an inverted inner edge, surrounding an open hole. Dissection or transplantation borne frag­ments containing sufficient cells of both marginal and central provenience reassort their cells to the normal relative position. Unbalanced compositions of fragments may be regulated by detachment of surplus material or (in the case of marginal surplus) also by fission, even in very small individuals. This way fission is involved in the regulation of the quantitative relation between these two kinds of cells. A monstrous modification of the shape and physiologic properties demonstrates a disturbance of these regulations. The marginal versus central differentiation manifests a radial polarity, till now unknown as to the relation to the histologically discerned cell types.
Notizen: The Pheromone Receptor System of Male Eulia ministrana L., with Notes on Other Cnephasiini Moths
Authors: Priesner Ernst
Published: August 2018

The antennal Sensilla trichodea of male Eulia ministrana (Tortricidae: Cnephasiini) contain specialist receptor cells for the sex-attractant components (Z)-9-and (Z)-11-tetra-decenyl acetate and the attraction-inhibitors (E)-11 -tetra-decenyl acetate, (Z)-7-dodecenyl acetate, and (Z)-11 -hexa-decenyl acetate. The significance of the latter two compounds as potential sex pheromone components in Tortri­cidae is considered.
Notizen: Isolation and Respiratory Assay of Earthworm Body Wall Mitochondria
Authors: Rao T. V. , Biswal U. C.
Published: August 2018

Out of several media tested, KCl medium containing BSA was found to be most suitable for isolation of functionally efficient mitochondria from earthworms. Respiration and oxidative phosphorylation in isolated mitochondria are demonstrated in the presence of cytochrome c and BSA in reaction medium.

Introduction - The details of the respiratory metabolism in earthworm are yet to be established. There are only a few contradictory reports on the nature of its respiratory enzyme components [1]. While, cytochrome oxidase, succinoxidase, succinate dehydrogenase were identified in earthworm tissue homogenates, the presence of Kreb′s cycle enzymes could not be demonstrated. Very little information is available on earthworm mitochondria except one report where it is isolated in 0.44 ᴍ mannitol [2]. Mitochondria from invertebrates like insects and crustaceans are isolated and characterized [3, 4]. But such methods cannot be extended to earthworms as it is known that conditions for isolation and assay of mitochondria are highly system specific [5].
Notizen: Neuroanatomical Evidence for Electroreception in Lampreys
Authors: Fritzsch Bemd , Caprona M .-Dominique Crapon de , Wächtler Klaus , Körtje Karl-Heinz
Published: August 2018

The patterns of the anterior lateral-line afferents of Lampetra fluviatilis as revealed by transganglionic trans­port of horseradish peroxidase are described. The afferents form two roots in entering the rhombencephalon. Fibers of the dorsalmost root can be traced to a short dorsal fascicle which runs along the dorsal nucleus. The ventral roots form two fascicles adjacent to the nucleus intermedius. Comparison with urodeles indicates that lampreys, like urodeles and other anamniotic vertebrates are electroreceptive.
De novo Synthesis and Levels of Cytochrome c and a Biliprotein during Pupal-Adult Development of a Butterfly, Pieris brassicae
Authors: Kayser Hartmut
Published: August 2018

Using a sensitive pH-difference spectroscopic method in combination with a three-column procedure of ion-exchange chromatography (overall yield 94%) the levels of cytochrome c in the large white butterfly, Pieris brassicae, were determined from the last larval instar to the adult insect. In the larva cytochrome concentration reached a maximum at mid instar and sub­sequently decreased to very low values in the pupa. During adult development the level of cytochrome c increased 50-fold in males and 43-fold in females; this sexual difference was expressed only after adult emergence. Biliverdin IXγ which occurs as a specific biliprotein complex was accumulated during the last larval instar and also in young butterflies. De novo synthesis of heme c, biliverdin IXγ and the corresponding apoproteins was demonstrated in newly emerged butterflies by injections of radiolabeled 5-aminolevulinate, lysine, leucine, and succinate, respectively. Cycloheximide inhibited labeling of both apoproteins and of heme c to 90% but that of the bilin to only 25%. This suggests that in cytochrome c but not in the biliprotein formation of the holoprotein depended on a coordinated synthesis of both constituents. In­corporation of 5-aminolevulinate into the biliprotein exceeded that into cytochrome c sevenfold indicating that biliverdin IXγ is the major product of the heme pathway in P. brassicae. The results are discussed in relation to the formation of mitochondria and flight muscles during postembryonic development of insects.
Surface Pressure Hysteresis of Mixed Lipid/Protein Monolayers: Applications to the Alveolar Dynamics
Authors: Mutafchieva Rada , Panaiotov Ivan , Dimitrov Dimiter S.
Published: August 2018

Mixed Lipid/Protein Monolayers, Alveolar Surfactant, Monolayer Models Experimental data on surface pressure-surface area hysteresis of mixed serum albumin/dipal-mitoyl lecithin/sphingomyelin monolayers in the Langmuir trough are presented. Several possible physicochemical mechanisms of the hysteresis are discussed: Marangoni effect, surface pressure relaxations, bulk-to-surface diffusion interchange, and collapse. Depending on the concrete conditions each of these mechanisms can be important. Possible applications of these results to the alveolar dynamics are presented and discussed on the basis of the balloon model of the alveolus. The main conclusions of biological importance are that 1) the alveolar stability depends on the DPL/SM ratio as well as on the protein content. Under normal breathing conditions the surface pressure hysteresis is small and does not play a decisive role in the alveolar dynamics. 2) At large extent of compression the collapse predominates in determining the hysteretic behavior of the alveolar surface.
Produktion pflanzlicher C6-Wundgase und ihre Wirkung auf einige phytopathogene Pilze / Production of C6-Wound Gases by Plants and the Effect on Some Phytopathogenic Fungi
Authors: Urbasch Irene
Published: August 2018

Abastract

The production of C6-wound gases by cultivated and wild tomato plants (Lycopersicon esculenium Mill., L. hirsutum Humb. et Bonpl., L. peruvianum (L.) Mill., L. pimpinellifolium Mill., L. glandulosum C. H. Muller) and the tree tomato (Cyphomandra betacea (Cav.) Sendtn.) was investigated. The genuine mixture of compounds and the single compounds showed antifungal properties against the phytopathogenic fungi Botrytis cinerea Pers., Rhizoctonia solani Kühn, Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder & Hansen, Didymelia lycopersici Kleb, and Cladosporium fulvum Cooke.
Amino Acid Composition of Cockroach Hypertrehalosaemic Hormones
Authors: Gäde Gerd
Published: August 2018

Hypertrehalosaemic hormones I and II from the corpus cardiacum of the American cockroach (Periplaneta americana) were separated by reversed-phase high-performance liquid chromato­graphy using a Nucleosil C18 column with a trifluoroacetic acid/acetonitrile gradient. The eluent was monitored at 206 nm and the hypertrehalosaemic activity detected by bioassay. The amino acid compositions of hypertrehalosaemic hormone I and II were determined after acid hydrolysis with HCl or methanesulfonic acid. Both neurohormones are octapeptides. Hypertrehalosaemic hormone I contained the amino acids Asp(2), Ser, Glu, Pro, Val, Phe and Trp, whereas hyper­trehalosaemic hormone II contained the amino acid residues Asp, Thr(2), Glu, Pro, Leu, Phe and Trp.
Absorption Spectra of Phytochrome Intermediates
Authors: Eilfeld Peter , Rüdiger Wolfhart
Published: August 2018

Native phytochrome (124 kdalton) was isolated from etiolated seedlings of Avena sativa L. cv. Pirol (Baywa, Munich). From low temperature spectra (0°C to - 165 °C) of phytochrome samples irradiated either with red or far-red light, spectra of intermediates were calculated. Both absorption bands of the phytochrome chromophore were reported. On the pathway Pr → Pfr, native phytochrome does not form a bleached intermediate (meta-Rb) in contrast to degraded phytochrome.

An additional intermediate, meta-Rc (λmax = 725 nm), is formed instead. On the reverse pathway only two intermediates were found, lumi-F and meta-F. Oscillator strengths′ values were calculated and interpreted in terms of chromophore conformation. A scheme of intermediates for native phytochrome is presented.
Biochemical Characterization of Propylglyoxal Bis(guanylhydrazone). Facile Synthesis of Monoalkylglyoxal Bis(guanylhydrazones)
Authors: Elo Hannu , Laine Raija , Alhonen-Hongisto Leena , Jänne Juhani , Mutikainen Ilpo , Lumme Paavo
Published: August 2018

Propylglyoxal Bis(guanylhydrazone). Ethylglyoxal Bis(guanylhydrazone), Adenosylmethionine Decarboxylase Inhibition. Tumor Cells, Cellular Uptake Propylglyoxal bis(guanylhydrazone) sulfate, a novel analog of the well-known antileukemic drug methylglyoxal bis(guanylhydrazone), has been prepared from 2,2-dibromopentanal, and the compound has been characterized biochemically. Although it is a powerful inhibitor of S-adenosylmethionine decarboxylase, its Ki, value (0.2 μᴍ) is considerably higher than that of ethylglyoxal bis(guanylhydrazone) (0.06 μᴍ). The compound is only poorly taken up by tumor cells, and its accumulation is not stimulated by a prior exposure of the tumor cells to di-fluoromethylornithine, a compound that causes polyamine depletion. Thus, the uptake charac­ teristics of the compound are similar to those of ethylglyoxal bis(guanylhydrazone), but in striking contrast to those of methylglyoxal and glyoxal bis(guanylhydrazones). Since the configuration of the double bonds in glyoxal, methylglyoxal and propylglyoxal bis(guanylhydrazones) has been shown to be identical, the different uptake characteristics are probably only due to differences in side chain size and/or hydrophobicity.
Further Observations on Periodicities of Nucleotide Occurrences in Natural DNA's
Authors: Furlong N. Burr , Marien Koenraad
Published: August 2018

There are non-random features in the occurrences of nucleotides in the DNA’s of certain organisms which are detectable by statistical analyses of the entire sequence. Earlier, using the bacteriophage Phi-X 174 DNA sequence, we had reported that the self-information values for one type of dinucleotide association showed a marked periodicity when their autocorrelation coefficients were graphed. A similar, but computationally simpler, analysis has been developed which gives a comparable indication of periodicity. The difference, in average autocorrelation coefficients obtained with this analysis, between the peak values and all others has been used as an index to compare the extent of periodic non-randomness for a series of natural DNA sequences and for various artificial sequences. Calculations show that triplet periodicity, the relationship between dinucleotides separated by a single nucleotide, is characteristic only of the natural sequences of certain filamentous phages and is not found prominently in any other DNA analyzed (including sequences of similar length from plasmids, yeast, bacteria and higher animals). By shuffling nucleotides in a given sequence or by substituting selected nucleotides to alter various positions in both periodic and aperiodic sequences, we have found that an excess or deficiency of a given nucleotide at one of the three positions in a triplet reading frame can simulate the periodic characteristic. Thus, it appears that this global statistical analysis detects the tendency for single­ strand phages to utilize a specific nucleotide, rather than one randomly selected, to constitute codons.
Seasonal Variation of Free Flavone Aglycones from Sideritis leucantha (Lamiaceae)
Authors: Barberán F. A. T. , Tomás F. , Núñez J. M.
Published: August 2018

A quantitative and qualitative study of the seasonal variation of free flavone aglycones from Sideritis leucantha (Lamiaceae) has been carried out by means of HPLC. The flavonoid pattern remained unvariable with seasonal varia­ tion supporting flavonoid aglycones as idoneous taxonomic markers. Quantitative variations were observed, being the summer months which yielded a higher content in these compounds. These highly methylated flavone aglycones are located in the leaves surface as part of the excretion mate­ rial.
The UV Absorption Spectra of the C(5) and C(6) OH Adduct Radicals of Uracil and Thymine Derivatives. A Pulse Radiolysis Study
Authors: Deeble David J. , Sonntag Clemens von
Published: August 2018

Using pulse radiolysis the UV spectra of the C(6) OH adduct radicals of 1,3-dimethyluracil and 1,3-dimethylthy-mine were obtained by reacting the formate radical with the corresponding 5-bromo-5,6-dihydro-6-hydroxy derivatives. In the reaction of the pyrimidines with OH radicals a mixture of C(5) and C(6) OH adduct radicals is formed. From the known ratios in which these two radicals are formed and the spectra of the C(6) OH adduct radicals, the spectra of the C(5) OH adducts were calculated.
Specificity of Sexual Attractants in Xestia triangulum Hufn. and X. ditrapezium Schiff. (Lepidoptera: Noctuidae)
Authors: Priesner E.
Published: August 2018

Electrophysiological analysis of male antennal Sensilla trichodea in Xestia triangulum and X. ditrapezium showed that they contain the same five types of receptor cells in both species. These cells responded specifically to the (Z)-alkenyl acetates Z7-12:Ac, Z5-14:Ac, Z7-14:Ac, Z9-14:Ac and Z 11-14:Ac. Yet, in field trapping tests, male X. triangulum were highly attracted to pure Z5-14:Ac as a single compound, whereas male X. ditrapezium responded specifically to a ternary combination of Z5-/ Z7-/ Z9-14: Ac with the Z7 isomer as the major constituent. The four other “key compounds” in X. triangulum, and the other two in X. ditrapezium, inhibited trap captures. The results are considered in view of the close taxonomic relationship of the two species and their potential reproductive isolation from other, pheromonally-related noctuid moths.
Ingibitors of Sexual Attraction in the Moth Agrotis exclamationis
Authors: Priesner E.
Published: August 2018

The sex-attractant system of the dart moth Agrotis exclamationis (L.) (Noctuidae) was re-investigated with electrophysiological and field trapping tests. The identified pheromone components (Z)-5-tetradecenyl acetate and (Z)-9-tetradecenyl acetate elicited maximum trap captures when combined in a Z5-/Z9-mixture ratio of between 100/10 and 100/20, in contrast to an earlier reported mixture optimum of 100/5. Each compound activated a particular type of receptor cell located in the male antennal hair sensilla. Three further cell types discovered in these sensilla responded specifically to the non-pheromonal compounds (Z)-7-dodecenyl acetate and (Z)-7-and (Z)-11-tetra-decenyl acetate. These latter compounds did not show attractive or synergistic properties in field trapping tests but rather reduced captures when added to the binary pheromone blend as a third component. The biological functions of these three “attraction-inhibitors” remain unidentified.
Isolation of Vacuoles from the Upper Epidermis of Petunia Hybrida Petals. II. Vacuolar Localization of Some Hydrolases
Authors: Aerts J. M. F. G. , Schram A. W.
Published: August 2018

In vacuoles isolated from petal upper epidermis of Petunia hybrida through polybase-induced lysis of protoplasts the vacuolar localization of α-mannosidase and α-galactosidase was demon­strated. No association was observed between the tonoplast and these hydrolases. Protoplasts from different mutant lines blocked in anthocyanin biosynthesis were treated with DEAE-dextran to release vacuoles. The differences in quality of the obtained vacuolar preparations indicated the relation between mutant line used and successful application of the polybase-procedure.
Isoceroptene, a Novel Polyphenol from Pityrogramma triangularis
Authors: Markham Kenneth R. , Vilain Christian , Wollenweber Eckhard , Dietz Volker H. , Schilling Gerhard
Published: August 2018

Isoceroptene, a polyphenol isolated in trace amount from the farinose frond exudate of Pityro­gramma triangularis, is shown by spectroscopic means to possess the structure of one of the two possible “flavanone” isomers formed by ring closure of the “chalcone” ceroptene. The tautomeric structures best representing ceroptene and a related dihydrochalcone from Myrica gale are defined by 1H-NMR spectroscopy.
Are Spinach Chloroplasts Involved in Flavonoid O-Methylation?
Authors: Thresh Kim , Ibrahim Ragai K.
Published: August 2018

Intact spinach chloroplasts, which were isolated on a cushion of Percoll and purified on discon­tinuous sucrose gradients, were found to adsorb appreciable amounts of high specific activity, cytosolic O-methyltransferases. The latter activity was readily eliminated after washing the chloroplast pellet with 0.1 ᴍ phosphate in sucrose gradient buffer and finally with 0 .1% nonidet. Furthermore, the OMT activity of spinach leaves was resolved by chromatography on DEAE-Sepharose CL-6B into caffeic acid (COMT) and flavonoid (FOMT) O-methyltransferase ac­tivities, and purified to 30-and 50-fold, respectively. The similarities between the FOMT/COMT activity ratios and the methylation patterns of intact chloroplasts and their supernatants, as well as those of purified leaf preparations, suggest non-specific binding of cytosolic OMTs to chloroplast envelopes.

It is concluded, therefore, that spinach chloroplasts are not involved in the methylation of phenylpropanoid or flavonoid compounds. These results call attention for the re-evaluation of the role of this organelle in the biosynthesis or accumulation of plant secondary metabolites.