Band 43, Heft 1-2

From Antitrichia curtipendula and Racomitrium lanuginosum 5′,3‴-dihydroxyrobustaflavone and 5′, 8″-biluteolin were isolated. In Plagiomnium elatum the new biflavone 5′-hydroxyamentoflavone was detected

Three isoflavonoids obtained from a methanolic extract of Pueraria mirifica roots have been identified as 3,9-dihydroxy-8-methoxy-7-(3,3-dimethylallyl)-coumestan (mirificoumestan), 3,9-dihydroxy- 8-methoxy-7-(3-hydroxy-3-methylbutyl)-coumestan (mirificoumestan hydrate), and 3,9- dihydroxy-8-methoxy-7-(2,3-dihydroxy-3-methylbutyl)-coumestan (mirificoumestan glycol). These new coumestans co-occur with coumestrol (3,9-dihydroxycoumestan), a compound already found in P. mirifica roots

Blue light-grown gametophytes of Anemia phyllitidis were used for the in vivo synthesis of radioactively labeled dilinoylgalactosylglycerol, a potential intermediate in the synthesis of linolenic acid. Optimal yield was obtained by incubating gametophytes with [ 14 C]linoleate first for 2 h under anaerobic conditions followed by 46 h under aerobic conditions. As product [ 14 C]dilinoylgalactosylglycerol was identified

Marine algae, maintained for one month under blue, white and red light were rather rich in lipids but obviously poor in fat (triacylglycerols). These lipids consisted predominantly of glycolipids and phospholipids. Irrespective of the light quality, the major constituent fatty acids in lipids of these algae were, in most cases, those with 20 carbon atoms. The light quality had a definite effect on the proportion of arachidonic acid in the lipids of certain algae. Thus, the proportion of arachidonic acid in Enteromorpha intestinalis maintained under white light was 45% and in Sargassum salicifolium kept under red light 25% of the total constituent fatty acids in the total algal lipids

Quantity and composition of epicuticular wax of Euphorbia aphylla were examined. The wax contained the common lipid components n-alkanes, wax esters, pr. alcohols, fatty acids and in traces aldehydes and acetates all occurring in homologous series. Additionally, several triterpenols such as β-amyrin, α-amyrin, lupeol and simiarenol were found. With the exception of simiarenol these triterpenols occurred free as well as esterified with acetic acid and fatty acids. The ketones, oleanen-3-one, ursen-3-one and lupen-3-one have also been identified

The brown-rot fungus Lentinus lepideus (Fr.: Fr.) Fr. FPRL 7B (Basidiomycotina) was cultivated on a defined synthetic liquid medium containing glucose (2%), isoleucine (0.15%), and mineral salts for 105 days. The steam distillate was separated by column chromatography. Three novel sesquiterpene ethers with muurolane skeleton (lentideusether, isolentideusether, and 10-hydroxylentideusether) were isolated and their structures elucidated by spectroscopic methods, in particular by 1 H NMR spectra and by two-dimensional 1 H/ 1 H- and 13 C/ 1 H-chemical shift correlation. These compounds are described for the first time as natural products. As a further metabolite, the acyclic sesquiterpene alcohol terrestrol was identified

(±)-[2- 14 C)Jasmonic acid has been synthesized in nearly 50% yield via the route of the Michael addition starting from 2-(2Z-pentenyl)-2-cyclopenten-1-one and diethyl [2- 14 C]malonate followed by saponification and decarboxylation of the Michael products in one step

Hydroxycinnamoyltransferase activities which catalyze the formation of O-hydroxycinnamoyl- (p-coumaroyl-, feruloyl-, and sinapoyl-)-glucaric acids via the corresponding 1-O-hydroxycinnamoyl- β-glucoses, and O-(p-coumaroyl)-quinic acid and O-(p-coumaroyl)-shikimic acid both via p-coumaroyl-CoA thioester have been isolated from leaves of Cestrum elegáns D. F. L. v. Schlechtendal. The enzymic activities involved could be classified as 1-O-hydroxycinnamoyl-βglucose : glucaric acid hydroxycinnamoyltransferase (EC 2.3.1.- ) and p-coumaroyl-CoA : quinic acid/shikimic acid hydroxycinnamoyltransferase (EC 2.3.1. - ). This is the first time that both the O-glucoside- and the S-CoA-dependent activities in phenolic acid-ester formation were found to be present in the same plant

Insoluble phenolics have been isolated and identified from Norway spruce (Picea abies [L.] KARST.) needles as cell wall-bound astragalin (kaempferol 3-O-β-glucoside) and p-coumaric acid as major components, and ferulic acid as a minor one. They probably mainly occur as lignincarbohydrate complexes

A leaf-differentiating callus culture and a root organ culture of Pimpinella anisum have been established in liquid nutrition medium. Their behaviour in accumulation of phenylpropanoids was shown to be different from that of the entire plant. This makes them, together with their special growth behaviour, suitable for labelling experiments with the biosynthesis of pseudoisoeugenols

The effect of the herbicides and aryloxy-phenoxy-propionic acid derivatives diclofop, fenoxaprop, fluazifop and haloxyfop and their ethyl, methyl or butyl esters on the de novo fatty-acid biosynthesis of isolated chloroplasts was investigated with intact chloroplasts isolated from sensitive grasses (Poaceae) and tolerant dicotyledonous plants (Pisum, Spinacia). The 4 herbicides (free-acid form) block the de novo fatty-acid biosynthesis ([2- 14 C]acetate incorporation into the total fatty-acid fraction) of the sensitive Avena chloroplasts in a dose-dependent manner. The I 50- values (a 50% inhibition of the [ 14 C]acetate incorporation) lie in the range of 10 -7 to 2 x 10 -6 ᴍ. The ethyl or methyl esters (diclofop, fenoxaprop, haloxyfop) and butyl ester (fluazifop) do not affect the de novo fatty-acid biosynthesis of isolated chloroplasts or only at a very high concentration of ca. 10 -4 ᴍ. In contrast, the de novo fatty-acid biosynthesis of the tolerant dicotyledonous species (pea, spinach) is not affected by the 4 aryloxy-phenoxy-propionic acid herbicides. In an enzyme preparation isolated from chloroplasts of the herbicide-sensitive barley plants the de novo fatty-acid biosynthesis from [ 14 C]acetate and [ 14 C]acetyl-CoA is blocked by all 4 herbicides (free acids), whereas that of [ 14 C]malonate and [ 14 C]malonyl-CoA is not affected. This strongly suggests that the target of all 4 herbicides (free-acid form) is the acetyl-CoA carboxylase within the chloroplasts. The applied ester derivatives, in turn, which are ineffective in the isolated chloroplast test system, have equally little or no effect on the activity of the acetyl-CoA carboxylase. It is assumed that the acetyl-CoA carboxylase of the tolerant dicot plants investigated is modified in such a way that the 4 herbicides cannot bind to and affect the target

The transient absorption recovery induced in phycocyanin trimers by picosecond pulses of variable wavelength (570-620 nm) has been recorded and analyzed by applying a least-squares multi-exponential fit procedure. The results suggest that in native PC trimers the chromophores exhibit a microheterogeneity with the effect that the derived apparent lifetimes are functions of excitation and probing wavelength. It is suggested that, due to strong excitonic coupling between a-84 and β-84 chromophores, the lifetime of the terminal acceptor state is reduced to about 900 ps; the apparent energy transfer time from chromophore β-155 to a-84 and β-84 chromophores varies between 20-50 ps depending on the actual chromophore-protein arrangement (microheterogeneity)

From Antitrichia curtipendula and Racomitrium lanuginosum 5′,3‴-dihydroxyrobustaflavone and 5′, 8″-biluteolin were isolated. In Plagiomnium elatum the new biflavone 5′-hydroxyamentoflavone was detected

In previous papers it has been shown that octocalcium phospate OCP occurs in bone mineral of vertebrates. Although this compound is not stable, there is a continuous new-formation of OCP due to bone turnover. Literature data of the calcium and phosphate concentrations in the blood plasma of vertebrates were collected and the degree of saturation with OCP was calculated. The results show that blood plasma of vertebrates is almost saturated with OCP. This fact indicates that OCP is the solubility controlling phase in the mineral of vertebrates. Further it verifies the expectation based on physicochemical theory that the interaction between body fluids and bone mineral is important in the calcium and phosphate homeostasis

Spectrally pure B 800-850 light harvesting complexes of Rhodopseudomonas acidophila 7750 were prepared by chromatography of LDAO-solubilised photosynthetic membranes on Whatmann DE-52 ion exchange resin. Two low molecular mass polypeptides (α, β) have been isolated by organic solvent extraction of the lyophilised B 800-850 light harvesting complexes. Their primary structures were determined by liquid phase sequencer runs, by the sequence analyses of C-terminal o-iodosobenzoic acid fragments, by hydrazinolysis and by carboxypeptidase degradation. B 800-850-a consists of 53 amino acids and is 45.3% and 50.9% homologous to the B 800-850- a antenna polypeptides of Rhodobacter sphaeroides and Rhodobacter capsulatus, respectively. The second very short polypeptide (B800-850-β, 41 amino acids) is 61.0% and 56.1% homologous to the corresponding polypeptides of Rb. sphaeroides and Rb. capsulatus. The molar ratio of the two polypeptides is about 1:1. Both polypeptides show a hydrophilic N-terminal domain, a very hydrophobic central domain and a short C-terminal domain. In both polypeptides the typical His residues, identified in all antenna polypeptides of purple nonsulphur bacteria as possible bacteriochlorophyll binding sites, were found

Chromophore conformation and protein secondary structure of biliproteins from the butterfly, Pieris brassicae, and the moth, Cerura vinula, have been investigated by absorption, circular dichroism and fluorescence spectroscopy. The chromophore of the P. brassicae protein, biliverdin IXy, has probably a cyclic-helical structure similar to that of free bile pigments of the biliverdin type. Though achiral by structure the chromophore displays strong optical activity in the native protein-bound state, but becomes inactive after urea denaturation of the protein. A minor biliprotein from P. brassicae shows absorption, circular dichroism and fluorescence spectra identical to the main biliprotein. In the biliprotein from Cerura vinula the structure of the pigment is still unknown. It has a semi-open conformation intermediate between that of the Pieris proteins and that of the phycobiliprotein, C-phycocyanin, and it retains optical activity after urea denaturation. The band widths and the size of the Stokes shifts of the fluorescence spectra indicate a high degree of conformational flexibility of the chromophores in the two Pieris pigments, and a decreased flexibility in the one from Cerura. In the biliproteins from both insects the polypeptides are low in a-helix content compared to that of phycobiliproteins. From these and earlier data, insect and algal biliproteins seem to be related only distantly if at all, but there exist also considerable differences among insect biliproteins from different species

Anticodon-anticodon pairing of complementary tRNA’s has been studied by fluorescence temperature jump measurements in the presence of different ligands as an approach for the evaluation of ligand binding to tRNA. This procedure is particularly useful for ligands which do not show spectroscopic changes upon binding, but affect the pairing potential of anticodons. Addition of phenylalanine-, tyrosine- and tryptophan-amide leads to a substantial decrease of the tRNA Phe -tRNA Glu pairing constant K p , whereas K p remains almost unaffected by addition of leucine amide and increases upon addition of glycine amide. The effects observed for the aromatic amino acid amides can be described quantitatively by a site binding model with preferential binding of the amides to tRNA Phe . The binding constants evaluated according to this model (Pheamide 120 M -1 , Tyr-amide 160 M -1 and Trp-amide 580 M -1 ) are consistent with values obtained independently by fluorescence titrations with tRNA Phe . Selective binding of these amino acid residues to tRNA Phe is deduced from the observed concentration dependence, which is not compatible with a corresponding binding process to tRNA Glu . Addition of glutamic acid diamide induces an increase of the tRNA Phe • tRNA Glu pairing constant, which is however equivalent to that observed for tRNA Phe -tRNA Lys pairing and thus does not demonstrate a selective binding to tRNA °1 u . The pairing of tRNA Phe with tRNA Glu is strongly enhanced by addition of Mg 2+ or spermine. Evaluation of the Mg 2+ data by a site model leads to constants of 360 M -1 for the binding of Mg 2+ to monomer tRNA and 3000 M -1 for the binding of Mg 2+ to the tRNA Phet RNA Glu dimer. A comparison of the enhanced pairing observed in the presence of Mg 2+ , which is known to induce a 3′-stack conformation of the anticodon loop, with the reduced pairing affinity observed in the presence of aromatic amino acid amides suggests induction of a 5′-stack conformation by the latter ligands

Pyrrolizidine alkaloid derivatives are present in the androconial (male scent) organs of Prittwitzia hymenaea, Mechanitis isthmia veritabilis, Tithorea harmónia fúria (Lep., Ithomiinae), Amauris echeria and Euploea sylvester (Lep., Danainae). While the ithomiines contain the new pyrrolizidine alkaloid derivative methyl hydroxydanaidoate, the danaines contain the known derivatives danaidone and hydroxydanaidal. In addition, 2,2,6-trimethyl-2-cyclohexen-1,4-dione (oxoisophorone) and related terpenoids have been identified from Amauris, Euploea and Prittwitzia as well as from the flowers of Buddleja davidii (Loganiaceae). Three new naturally occurring bishomoterpenes as well as mono- and sesquiterpenes and aromatic compounds add to the formation of species specific blends in the scent organs of the butterflies

The electric behaviour of the mormyrid Gnathonemus petersii is changed by dopaminergic drugs applied to the aquarium water. The upper limit of the interpuis interval distributions is significantly shifted to shorter intervals by apomorphine-HCl (.082-,328 mg/ml), and to longer intervals by haloperidol (.041 -.164 mg/ml). The effect of apomorphine is antagonized by haloperidol. Probably, a dopamin system is involved in the neural control of the electric organ

The corpora cardiaca of the cockroach Nauphoeta cinerea contain a hypertrehalosaemic hormone (HTH) which is chemically characterized as a blocked decapeptide. The synthetic HTH shows the same chromatographic behaviour as the material isolated from corpora cardiaca. The synthetic peptide causes hypertrehalosaemia and fat body glycogen phosphorylase-activation in N. cinerea as well as in the American cockroach, Periplaneta americana in a dose-dependent fashion. It is calculated that one gland from N. cinerea stores about 50 pmol of HTH. Roughly 10% of the total available hormone in the gland is released in vitro during exposure to an elevated potassium saline which causes depolarization of the neurosecretory cells

The androgen receptor of murine preputial gland showed in binding experiments a biphasic saturation curve and a biphasic Scatchard plot. The receptor converted from an 8.5-9 S form to a 4.5-5 S form in high ionic strength buffer. The apparent dissociation constant was K D 0.5 ± 0.2 nᴍ for the 8.5-9 S receptor form. A 6.5-7 S receptor form could be detected in some experiments. The ligand specificity was evaluated by competition experiments: testosterone > androstenedione > dihydrotestosterone > androstanediol > estradiol > progesterone > dexamethasone. The receptor of murine preputial gland was less stable than the androgen receptor of skeletal muscle of the same mice

The sedimentation of nucleoids from thymic and splenic cells of rats was tested following totalbody X-irradiation (TBI) with doses ranging from 24 to 1520 cGy. The principal results may be summarized as follows: 1) The nucleoid sedimentation of the cells was reduced immediately after TBI with doses of ≥ 760 cGy. In the following postirradiation period, an enhancement of sedimentation rate has been observed which could be neutralized by addition of proteinase K to the nucleoid preparation. 2) When nucleoids were prepared 6 h after TBI with doses ≥ 190 cGy, beside the main nucleoid band a smaller nucleoid fraction appeared in the ethidium bromide containing saccharose gradient. This fraction was of less sedimentability than the main nucleoid peak and could not be distinguished from pure, high molecular DNA. - From the present results it is suggested that the reduction of the nucleoid sedimentation immediately following high doses of TBI is the result of primary (non-repaired) DNA lesions whereas the changes detectable some hours later are due to the secondary enzymatic changes connected with the interphase death of the cells. With respect to the detection of in vivo effects of X-irradiation, the nucleoid sedimentation has to be regarded much less sensitive than some biochemical and/or cytomorphological methods

It has been found that the decay of light triggered ATPase activity is paralleled by nonexchangeable type of binding of one ADP per mol of CF 1 . Inactivation of light triggered ATPase activity is a continuous process. It can be described mathematically as shown in this paper. Three simplified reaction schemes are described, each of them describing the mode of ATPase inactivation in a mechanistic way. A computer simulation of each model was performed and the results were compared to the observed experimental data. In the presence of phosphate our results were explained best by a model assuming that there is at first a rapid binding of ADP to “exchangeable” sites. Due to a slowly occurring change in the CF 1 protein with prolonged incubation, an increasing portion of the nucleotides can be found bound in a non-exchangeable way after some seconds of incubation. Our model does not rule out that this reaction sequence might be a part of a catalytic cycle in vivo. - Another result was the finding that there is an additional diminution of ATPase activity when phosphate is lacking

Heavy sarcoplasmic reticulum vesicles were reacted with ryanodine in 0.6 ᴍKCl 0.3 ᴍ sucrose at pH 6.3 and pH 7.0 at 20 °C. The inhibition of caffeine induced calcium release from actively loaded vesicles by ryanodine was applied to monitor time course and attainment of equilibrium of the interaction of ryanodine with its receptors in the vesicular membranes. At ryanodine concentrations rising from 0.1-100 μᴍ, the logarithms of the release amplitudes linearly decline with time. The dependence of the inactivation reaction on the concentration of ryanodine did not saturate in the applicable concentration range. The reaction halflife times are concentration dependent. At pH 7.0, the half times decline from 100 to 10 s when the ryanodine concentration is raised from 0.1 to 1 μᴍ. At pH 6.3 a corresponding decline occurs between 3 μᴍ and 100 μᴍ. The marked dependence of the inactivation reaction on medium pH requires reaction times of one and five hours at pH 7.0 and 6.3, respectively for the attainment of reaction equilibrium at low ryanodine concentrations. The dependence of the amplitude of calcium release on the concentration of added ryanodine has been evaluated as proposed by Gutfreund (Enzymes: Physical Principles, p. 71, Wiley-Interscience, London 1972) for the preparation’s affinity for ryanodine and its number of binding sites. At pH 7.0, preparations appear to contain only 0.7 pmol sites per mg protein having an affinity for ryanodine of 0.33 nᴍ -1 . The titration curves for caffeine induced calcium release, initial calcium uptake and final calcium level are identical, indicating that the three functions are controlled by the same receptor. Calcium induced calcium release, however, is only partially and differently affected by the occupancy of the high affinity ryanodine binding sites. The kinetic and equilibrium data for the effects of ryanodine were combined and analyzed on account of a two step reaction sequence. The corresponding dissociation and rate constants were evaluated and combined with reported data of [ 3 H]ryanodine binding (Pessah et al., J. Biol. Chem. 261, 8643-8648 (1986))

In the course of yellowing (senescence) the leaves of Vicia faba L. lose 95% of their chlorophyll. Gerontoplasts develop from chloroplasts and aggregate with the pycnotic mitochondria and the cell nucleus in the senescent cells (organelle aggregation). The gerontoplasts contain only a few, unstacked thylakoid membranes but a large number of carotinoid-containing plastoglobuli, which after the degration of chlorophyll presumably assume the light protection of the cells. The thylakoid membranes of the gerontoplasts were isolated by means of a flotation method. Their polypeptide composition is characterized by a high proportion of light-harvesting complex. Evidence of relatively high photochemical activity shows that functional thylakoid membranes are present in the premortal senescence state of leaves and this suggests that there is functional compartmentation of the hydrolytic processes in this stage of the leaves’ development