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NO ACTION DICHROISM fOR LIGHT-CONTROLLED fERN-SPORE GERMINATION

JOURNAL Of PLANT PHYSIOLOGY 1987年第1-2期129卷 119-128页

作者： HAUPT, W BJORN, LO UNIV LUND DEPT PLANT PHYSIOL S-22007 LUND 7 SWEDEN

Action dichroism for phytochrome-mediated light control of fern-spore germination [Dryopteris filix-mas L., Dryopteris paleacea L., Polystichum minutum L.] was searched for in several irradiation programs. The test irradiations consisted of a pair of linearly polarized red pulses with their planes of polarization identical or normal to each other. In no instance did these two combinations give different results, and thus, no action dichroism could be demonstrated. A theoretical calculation clearly shows that an action dichroism should be detected, if phytochrome were structurally fixed, provided some conditions are met. The negative result is discussed as a basis for further improvement of the experiments, for detecting or ruling out an action dichroism in non-directional light responses.

关键词： Dryopteris filix-mas L. Dryopteris paleacea L. Polystichum minutum L. action dichroism photoreceptor orientation phytochrome D action dichroism f fluence fR far red light (wavelength longer than 700 nm) Pfr (concentration of) phytochrome in fR absorbing form Pr (concentration of) phytochrome in red absorbing form Ptot concentration of total phytochrome R red light (wavelength less than 700 nm) ∥ parallel ⊥ perpendicular

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DETECTION Of TRP-P-1 AND TRP-P-2, CARCINOGENIC TRYPTOPHAN PYROLYSIS PRODUCTS, IN DIALYSIS fLUID Of PATIENTS WITH UREMIA

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MUTATION RESEARCH 1987年第1期179卷 33-40页

作者： MANABE, S YANAGISAWA, H GUO, SB ABE, S ISHIKAWA, S WADA, O Department of Hygiene and Preventive Medicine Faculty of Medicine University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113 Japan

In order to estimate the exposure levels of mutagenic and carcinogenic heterocyclic amines in humans, we developed a high-performance liquid chromatography method to detect 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) in dialysis fluid of patients with uremia. Using this methods, dialysis fluid of 12 patients who had received hemodialysis treatment or continuous ambulatory peritoneal dialysis was examined. Trp-P-1 was detected in dialysate of all uremic patients (727 .+-. 282 pmoles, n = 12). In patients who had been treated with continuous ambulatory peritoneal dialysis, the average amount of Trp-P-1 found in whole dialysate (6 l) per day was 710 .+-. 203 pmoles (mean .+-. S.D., n = 8). Moreover, Trp-P-2 could be detected in 5 out of 12 patients (206 .+-. 85 pmoles, n = 5). These results indicate that patients with uremia are actually exposed to carcinogenic tryptophan pyrolysis products. The average exposure level of Trp-P-1 in uremic patients apparently exceeded 710 pmoles (150 ng) per day.

关键词： Carcinogenic heterocyclic amines Dialysis fluid Ureamia Tryptophan pyrolysis products Glu-P-1 2-amino-6-methyldipyrido[1,2- a :3′, 2′- d ]imidazole, 67730-11-4 Glu-P-2 2-aminodipyrido[1,2- a :3′,2′- d ]imidazole, 67730-10-3 IQ 2-amino-3-methylimidazo-[4,5- f ]quinoline, 76180-96-6 MeIQ 2-amino-3,4-dimethylimidazo[4,5- f ]quinoline, 77094-11-2 MeIQx 2-amino 3-8-dimethylimidazo[4,5- f ]quinoxaline, 77500-04-0 Trp-P-1 3-amino-1,4,-dimethyl-5 H -pyrido[4,3- b ]indole, 62450-06-0 Trp-P-2 3-amino-1-methyl-5 H -pyridol[4,3- b ]indole, 62450-70-1

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LIGHT-INDUCED OXIDATION Of THE ACCEPTOR-SIDE fE(II) Of PHOTOSYSTEM-II BY EXOGENOUS QUINONES ACTING THROUGH THE QB BINDING-SITE .2. BLOCKAGE BY INHIBITORS AND THEIR EffECTS ON THE fE(III) ELECTRON-PARAMAGNETIC-RES SPECTRA

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第2期893卷 138-148页

作者： DINER, BA PETROULEAS, V INST BIOL PHYS CHIM F-75005 PARIS FRANCE NUCL RES CTR DEMOKRITOS ATHENS GREECE

four representative inhibitors of Photosystem II (PS II) QA- to QB electron transfer were shown to bind, at high concentrations, to PS II reaction centers having the acceptor-side non-heme iron in the fe(III) state. Three of the inhibitors studied, DCMU, o-phenanthroline and dinoseb, modified the EPR spectrum of the fe(III) relative to that obtained by ferricyanide oxidation in the absence of inhibitor. o-Phenanthroline gave particularly axial symmetry, while DCMU and dinoseb gave more rhombic configurations. The herbicide inhibitor, atrazine and its analogue, terbutryn, had no effect. The dissociation constants for inhibitor binding to reaction centers in the fe(III) state were measured directly and also estimated from shifts in the midpoint potential of the fe(III)/fe(II) couple and were shown to increase by factors of approx. 100, approx. 10 and 10-15 for DCMU (pH 7.5), atrazine (pH 7.0) and o-phenanthroline (pH 7.0), respectively, upon oxidation of the iron. Atrazine and o-phenanthroline, which induce the smallest changes in the midpoint potential of the fe(III)/fe(II) couple, were shown to inhibit light-induced oxidation of the fe(II) by phenyl-p-BQ, described in the preceding paper (Petrouleas, V. and Diner, B.A. (1987) Biochim. Biophys. Acta 893, 126-137). The extent of inhibition was much greater than would be predicted from a simple shift in the midpoint potential for fe(III)/fe(II) and we conclude that phenyl-p-BQ and the other quinones, which show light-induced oxidation, act through the QB binding site. It is also argued that reduction and oxidation of the iron by ferro- and ferricyanide, respectively, occur through this site. The effects of these inhibitors and of various quinones on the fe(III) environment are discussed with reference to the known contact points between the protein and o-phenanthroline and terbutryn in the QB binding pocket of Rhodopseudomonas viridis reaction centers (Michel, H., Epp, O. and Deisenhofer, J. (1986) EMBO J. 5, 2445-2451

关键词： Electron spin resonance Photosystem II Quinone-iron acceptor complex fe(III) Reduction-induced oxidation Herbicide inhibitor BBY Berthold, Babcock and Yocum (see Ref. 25) DCMU diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) EDTA ethylenediaminetetraacetate EPR electron paramagnetic resonance f fluorescence yield f 0 Photosystem II fluorescence yield with Q A oxidized Hepes 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid Mes 4-morpholineethanesulfonic acid p -BQ 1,4-benzoquinone PQ-9 plastoquinone a PS II Photosystem II RC reaction center Q A primary quinone electron acceptor Q B secondary quinone electron acceptor Q ex exogenous quinone

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TURN-OVER Of ELECTRON-DONORS IN PHOTOSYSTEM-I - DOUBLE-fLASH EXPERIMENTS WITH PEA-CHLOROPLASTS AND PHOTOSYSTEM-I PARTICLES

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第1期892卷 91-98页

作者： BOTTIN, H MATHIS, P Service de Biophysique Département de Biologie Centre d'Etudes Nucléaires de Saclay Gif-sur-Yvette France

Kinetic properties of the binding of plastocyanin to the Photosystem I (PS I) reaction center have been studied by measuring the reduction kinetics of photo-oxidized P-700 after two consecutive excitations, with flash absorption spectroscopy. In pea chloroplasts and in PS I particles, after two laser flash excitations separated by 50 .mu.s or less, P-700+ is reduced with a t1/2 = 110 .mu.s. No 12-.mu.s reduction phase, due to ''close'' bound plastocyanin electron donation to P-700+, can be detected. By increasing the delay between the flashes, the 12-.mu.s P-700+ reduction phase reappears and its half-time of reappearance is 110 .mu.s. Plastocyanin is shown to be involved in P-700+ reduction after the first and also the second excitations. Results are interpreted in terms of two plastocyanin molecules bound to the reaction center, the ''distant'' bound one replacing or re-reducing the ''close'' bound one after it has been oxidized.

关键词： Photosystem I P-700 Plastocyanin Cytochrome f Absorption kinetics Electron transfer (Pea chloroplasts) ΔA absorption change DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea Mes 4-morpholineethanesulphonic acid PC (I or II) reduced or oxidized plastocyanin PS I Photosystem I Tricine N -[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine

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THYLAKOID MEMBRANE-PROTEIN PHOSPHORYLATION MODIfIED THE EQUILIBRIUM BETWEEN PHOTOSYSTEM-II QUINONE ELECTRON-ACCEPTORS

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第2期894卷 138-145页

作者： HODGES, M BOUSSAC, A BRIANTAIS, JM UNIV PARIS 11 UTILISAT RAYONNMENT ELECTROMAGNET LABF-91405 ORSAYFRANCE

Chloroplast thylakoid membrane protein phosphorylation inhibits Photosystem-II-mediated electron transfer at saturating light intensities. Measurements of room temperature chlorophyll fluorescence have been used to monitor electron transfer reactions between the primary (Q A ) and secondary (Q B ) quinone acceptors of Photosystem II. The initial transfer from Q − A to Q B is not affected by the phosphorylation, although a second slow reoxidation phase is even slower after phosphorylation. After equilibrium is achieved between Q − A Q B and Q A Q − B there appears to be a higher concentration of Q − A in the phosphorylated membranes. This is explained by a phosphorylation-induced destabilisation of the anionic semiquinone, Q − B , as seen from the DCMU-stimulated fluorescence increase.

关键词： Chlorophyll fluorescence Electron transfer Photosynthesis Photosystem II Protein phosphorylation (Pea and lettuce chloroplast) Chl chlorophyll D1 herbicide-binding protein ( psbA gene product) D2 protein associated with PS II ( psbD gene product) DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea DPC diphenylcarbazide DPIP 2,6-dichlorophenolindophenol f 0 initial Chl fluorescence f M maximal Chl fluorescence Hepes N -2-hydroxyethylpiperazine- N ′-2-ethanesulphonic acid LHC light-harvesting Chl a b protein complex pBQ phenyl benzoquinone PQ plastoquinone PS Photosystem Q A primary quinone electron acceptor of PS II Q B secondary quinone electron acceptor of PS II

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SKELETAL BLOOD-fLOW IN METABOLIC DISORDERS Of THE SKELETON

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BONE 1987年第5期8卷 293-297页

作者： GREEN, JR REEVE, J TELLEZ, M VEALL, N WOOTTON, R MRC CLIN RES CTR BONE DIS RES GRP WATFORD RD HARROW HA1 3UK MIDDX ENGLAND NORTHWICK PK HOSP HARROW HA1 3UJ MIDDX ENGLAND

Results are presented of measurements of skeletal blood flow made in 80 patients with painful benign or malignant diseases of the skeleton, excluding patients with Paget''s disease. In crush fracture osteoporosis, total bone blood flow was slightly lower than normal although skeletal perfusion was normal. High values of bone blood flow were seen in 14/20 patients with osteomalacia and 3/12 patients with primary hyperparathyroidism. Very high values, comparable to those seen in the most severely affected patients with Paget''s disease, were seen in polyostotic fibrosis dysplasia, 2 out of 4 cases of Engelmann''s disease and 1 out of 3 cases of renal osteodystrophy. Results were less elevated in myositis ossificans, secondary skeletal involvement with breast and prostatic carcinomata, myelomatosis and sympathetic osteodystrophy.

关键词： Blood flow Metabolic Bone Disease 18 f Engelmann's Disease Myositis Ossificans

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THE HYPOTHALAMUS, INTRINSIC CONNECTIONS AND OUTfLOW PATHWAYS TO THE ENDOCRINE SYSTEM IN RELATION TO THE CONTROL Of fEEDING AND METABOLISM

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PROGRESS IN NEUROBIOLOGY 1987年第1期28卷 1-+页

作者： LUITEN, PGM TERHORST, GJ STEffENS, AB Department of Animal Physiology State University of Groningen P.O. Box 14 9750 AA Haren The Netherlands

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HALOGENATED 1,4-BENZOQUINONES AS IRREVERSIBLY BINDING INHIBITORS Of PHOTOSYNTHETIC ELECTRON-TRANSPORT

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第2期890卷 260-269页

作者： OETTMEIER, W MASSON, K DOSTATNI, R Lehrstuhl Biochemie der Pflanzen Ruhr-Universität Bochum F.R.G.

Halogenated 1,4-benzoquinones are effective inhibitors of photosynthetic electron transport through Photosystem II and the cytochrome b6/f-complex as well. Due to their properties as vinylogous acid halides they can react with nucleophilic groups of soluble molecules or membrane-bound proteins under formation of a covalent linkage. Despite its high inhibitory properties a 14C-labeled tetrabromo-1,4-benzoquinone (bromanil) shows no Michaelis-Menten type binding behaviour in isolated thylakoids. As detected by its covalent binding, [14C]bromanil in isolated spinach cytochrome b6/ f-complex binds to the 20 kDa Rieske iron sulfur protein and the 33-34 KDa cytochrome f. Upon [14C]bromanil treatment in spinach thylakoids the highest amount of radioactivity is found in a 20 kDa protein, which may be the Rieske protein, and a 41 kDa protein.

关键词： Photosystem II Cytochrome b 6 f complex Benzoquinone Inhibitor (Spinach chloroplast) atrazine 2-chloro-4-ethylamino-6-isopropylamino- s -triazine DBMIB 2,5-dibromo-3-methyl-6-isopropyl-1,4-benzoquinone DCIP dichlorophenolindophenol DCMU 3-(3′,4′-dichlorophenyl)-1,1-dimethylurea DNP-INT 2-iodo-2′,4,4′-trinitro-3-methyl-6-isopropyl-diphenylether DQH 2 durohydroquinone Chl chlorophyll QSAR quantitative structure-activity relationship TMPD N , N , N ′, N ′-tetramethyl- p -phenylenediamine UHDBT 5- n -undecyl-6-hydroxy-4,7-dioxobenzothiazole Cyt cytochrome

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THE E-T (ELEPHANT-TADPOLE) PARADOX NECESSITATES THE CONCEPT Of A UNIT Of B-CELL fUNCTION - THE PROTECTION

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MOLECULAR IMMUNOLOGY 1987年第7期24卷 675-697页

作者： LANGMAN, RE COHN, M Developmental Biology Laboratory The Salk Institute for Biological Studies P.O. Box 85800 San Diego CA 92138-9216 U.S.A.Received 12 November 1986 Accepted 17 February 1987 Available online 12 November 2002

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ROLE Of LIPIDS IN THE ORGANIZATION AND fUNCTION Of PHOTOSYSTEM-II STUDIED BY HOMOGENEOUS CATALYTIC-HYDROGENATION Of THYLAKOID MEMBRANES INSITU

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BIOCHIMICA ET BIOPHYSICA ACTA 1987年第1期891卷 68-74页

作者： HORVATH, G MELIS, A HIDEG, E DROPPA, M VIGH, L HUNGARIAN ACAD SCI BIOL RES CTR INST PLANT PHYSIOL POB 521 H-6701 SZEGED HUNGARY HUNGARIAN ACAD SCI BIOL RES CTR INST BIOCHEM H-6701 SZEGED HUNGARY

The effects of homogeneous catalytic hydrogenation on the organization and function of Photosystem II was investigated by fluorescence induction kinetic measurements with isolated chloroplasts. The results showed that saturation of the double bonds of fatty acyl constituents of membrane lipids had distinct effect on PS II. We found that progressive hydrogenation resulted in a gradual decrease of PS II electron transport with a concomitant increase of the initial fluorescence rise from f0, the non-variable level, to fp1, the intermediate plateau level, indicating that an optimal saturation level of fatty acids of membrane lipids is important in maintaining the efficient electron transfer from QA- to plastoquinone pool. In addition, the fluorescence induction kinetics of DCMU-poisoned chloroplasts showed that the proportion of PS ***. in the membrane was increased by hydrogenation, suggesting that the saturation level of fatty acids may play an important role in regulating the association of the peripheral chlorophyll a/b light-harvesting complex II (LHC II-peripheral) with PS ***., thus determining the PS II heterogeneity in PS ***. and PS ***.

关键词： Chloroplast lipid Homogeneous catalytic hydrogenation fluorescence induction Photosystem II heterogeneity Thylakoid membrane Membrane hydrogenation Chl chlorophyll f fluorescence LHC light-harvesting complex MGDG monogalactosyldiacylglycerol Pd(QS) 2 Pd(II) sulfonated alizarine complex PQ plastoquinone PS Photosystem Q A ‘primary’acceptors of PS II Q B ‘secondary’ acceptors of PS II

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