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H-1 HISTONE SYNTHESIS AND PHOSPHORYLATION IN MOUSE MAMMARY-GLAND INVITRO

MOLECULAR AND CELLULAR ENDOCRINOLOGY 1987年第1期54卷 35-41页

作者： HOHMANN, P HUGHES, C NEW YORK STATE DEPT HLTH ROSWELL PK MEM INST DEPT EXPTL BIOL 666 ELM ST BUFFALO NY 14263 USA

The synthesis and phosphorylation of H1 histones were studied in organ cultures of midpregnant mouse mammary glands exposed to various combinations of insulin, cortisol and prolactin over a 48-h period. The synthesis of specific H1 histone subtypes was changed only when all three hormones were present, and the effect of most pronounced during the first 24 h of culture, a period of cell replication. The 3-hormone combination also stimulated the phosphorylation of the N-terminal region of the H1 histone, and this also occurred maximally during the first 24 h of culture. The enhanced phosphorylation of the N-terminal region of the H1 histone included a site sensitive to phosphorylation by cyclic AMP-dependent protein kinase. Thus, hormones which stimulate mammary development in vitro influence the synthesis and specific phosphorylation of H1 histones during a period of cell replication preceding the expression of milk protein genes.

关键词： Lactogenic hormone Organ culture TCA trichloroacetic acid PCA perchloric acid I insulin f cortisol P prolactin

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COCKROACH SENSITIZATION IN LABORATORY WORKERS

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JOURNAL Of ALLERGY AND CLINICAL IMMUNOLOGY 1987年第4期80卷 586-590页

作者： STEINBERG, DR BERNSTEIN, DI GALLAGHER, JS ARLIAN, L BERNSTEIN, IL UNIV CINCINNATI MED CTRDEPT MEDDIV IMMUNOLML 563 231 BETHESDA AVE CINCINNATI OH 45267 USA WRIGHT STATE UNIV DEPT BIOL SCI & PHYSIOL DAYTON OH 45435 USA

Six laboratory workers who were exposed to American cockroaches (AC) and German cockroaches (GC) while they were performing immunologic experiments were evaluated for cockroach hypersensitivity. Prick skin testing and RAST were performed with whole body extracts (1:20 wt/vol) of AC, brown-banded (BB), and GC species as well as hemolymph and fecal (f) extracts of AC. Three of six workers reported work-related nasal and ocular symptoms associated with xenografting and bleeding of cockroaches. All three symptomatic workers exhibited cutaneous reactivity to at least one cockroach antigen. Elevated RAST binding was observed in on eof the three symptomatic workers. A nasal provocation to AC was positive in the most symptomatic worker at a provocative dose of 3.2 .times. 10-3 mg causing a 50% decrease of nasal flow rate from baseline. After pretreatment with nasal cromolyn, the provocative dose causing a 50% decrease from baseline increased to 2.6 .times. 10-1 mg. Nasal provocation with the same concentrations of AC were negative in two skin test negative subjects. RAST-inhibition studies demonstrated cross inhibition of the serum-specific IgE binding to AC-hemolymph by AC, GC, and BB whole body extracts. However, specific IgE binding to AC-f was inhibited by AC-f and AC but not by GC or BB whole body extracts, suggesting there was greater specificity of the f allergens. This study demonstrated that cockroach allergens elicit IgE-dependent upper respiratory sensitization in the workplace.

关键词： AC American cockroaches H Hemolymph BB Brown-banded cockroaches GC German cockroaches f fecal PD 50 Provocative dose of allergen required to cause a decrease of 50% of nasal flow rate from baseline Tm Tenebrio molitor

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IN PHOTOINHIBITED PHOTOSYSTEM-II PARTICLES PHEOPHYTIN PHOTOREDUCTION REMAINS UNIMPAIRED

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fEBS LETTERS 1987年第1期226卷 186-190页

作者： ALLAKHVERDIEV, SI SETLIKOVA, E KLIMOV, VV SETLIK, I CZECHOSLOVAK ACAD SCI INST MICROBIOL CS-37981 TREBON CZECHOSLOVAKIA

Oxygen-evolving photosystem II particles (DT 20) isolated from pea chloroplasts by digitonin-Triton X-100 fractionation were photoinhibited with 150 W. m(-2) white light, at 20°C under three conditions: aerobic, anaerobic and strongly reducing (E(h) poised to approx. -250 mV with dithionite). Hill reaction rate (H (20) + BQ)and variable fluorescence (fv) declined in parallel in all three cases with shortening half times: 30, 10 and 2.5 min, respectively. Light-induced absorbance changes at 685 nm characteristic of reversible photo accumulation of reduced pheophytin (& z -2.50 mV) remained essentially unchanged. We conclude that the three types of photoinhibitory treatment do not impair the separation of charges between chlorophyll P-680 and pheophytin in the photosystem II reaction center.

关键词： Photoinhibition Charge separation Pheophytin Oxygen-evolving PS II particle (Pea chloroplasts) PS photosystem RC reaction center P-680 the primary electron donor Pheo (pheophytin) the intermediary electron acceptor Q A the primary (quinone) electron acceptor in PS II f o , f v , f m constant, variable, maximum fluorescence HRR Hill reaction rate (H 2 O å BQ) BQ p -benzoquinone Mes 2-( N -morpholino)ethanesulfonic acid

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亚氟化银单晶体价带光电子谱及电子结构研究

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东北大学学报(自然科学版) 1987年第4期 438-441页

作者：孙凤久高桥隆佐川敬东北工学院日本东北大学

本文首次给出以 He-I 共振线和 Mg-K。线激发而得到的 Ag;f 单晶体全价带光电子谱。在 UPS 谱中发现三个显著的能带,从费米能级算起它们分别处于***4.6eV 以及*** 附近,它们分别标志 f2p 态、Ag4d 态以及两态的混合.实验结果与最近的 LA... 详细信息

本文首次给出以 He-I 共振线和 Mg-K。线激发而得到的 Ag;f 单晶体全价带光电子谱。在 UPS 谱中发现三个显著的能带,从费米能级算起它们分别处于***4.6eV 以及*** 附近,它们分别标志 f2p 态、Ag4d 态以及两态的混合.实验结果与最近的 LAPW 能带计算相比较表明,4d 带的计算结果相对于实验结果向较低的束缚能方向移动了约 leV,这表明 LAPW 计算中形成小椭球形费米面的第16号能带可能在费米能级之上,这对进一步研究该晶体的物理性质具有重要意义.

关键词：光电子谱 Ag f

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ELECTRONIC-STRUCTURE Of THE f+ CENTER IN THE ALKALINE-EARTH OXIDES

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JOURNAL Of PHYSICS AND CHEMISTRY Of SOLIDS 1986年第1期47卷 59-64页

作者： TAURIAN, OE KAI, AHT LOBATCH, V Quantum Chemistry Department Uppsala University Box 518 S-751 20 Uppsala Sweden

The multiple scattering Xα(MSXα) method is used in the study of the f + -centre in the alkaline earth oxides. The isotropic hyperfine constant and the optical absorption energies are evaluated. The calculated hyperfine constants are in good agreement with the experimental values. for the optical transition energies, agreement between the calculated and experimental values is somewhat poor. Nevertheless, the results show the expected decreasing behavior with increasing atomic number of the alkaline earth atom.

关键词： alkaline-earth-oxides f + -centre hyperfine constant optical absorption energy MSXα

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POLARON THEORY Of THE f-f' CONVERSION IN ALKALI-HALIDES

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JOURNAL Of PHYSICS AND CHEMISTRY Of SOLIDS 1986年第8期47卷 815-824页

作者： GEORGIEV, M MLADENOV, GM UNIV SOFIA FAC CHEMBU-1126 SOFIABULGARIA

Extending recent suggestions regarding the vibronic properties of f -centers in alkali halides, the following scenario is now proposed of the optical conversion of f -centers into f ′-centers: An excited f -center electron, formed by photobleaching in the f -band, passes into a bound polaron state before passing on to an f -center to give rise to an f ′-center. The detachment of the electron cloud from the excited f -center involves configurational tunneling in an exothermic process. However, both the tunneling barrier and the electron-transfer expectancy depend drastically on the host material leading to different activation energies and frequency factors of the conversion efficiency in different hosts. The f center-polaron conversion is effected through the strong coupling to at least two modes, one being the LO lattice mode of the crystal. The f to f ′ conversion efficiency for various hosts is calculated using a reaction-rate method and found to agree reasonably well with available experimental data.

关键词： Polarons color centers electron-phonon interaction strong coupling reaction rates quantum-mechanical tunneling low-temperature bleaching f -centers

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ELECTRON-PARAMAGNETIC RESONANCE EVIDENCE Of METAL-ION BINDING-SITES IN MICROCOCCUS-LYSODEIKTICUS (M-LUTEUS) f1-ATPASE

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BIOCHIMICA ET BIOPHYSICA ACTA 1986年第2期848卷 224-229页

作者： MOLLINEDO, f CANNISTRARO, S UNIV PERUGIA DEPARTIMENTO FIS BIOF MOLECOL GRP I-06100 PERUGIA ITALY

Evidence is presented for the presence of divalent cation binding sites in purified f1-ATPase from Micrococcus lysodeikticus (Micrococcus luteus). Electron paramagnetic resonance studies of native f1-ATPase indicate that the enzyme binds Mn2+ and Cu2+. Scatchard-type plot for Mn2+ binding to the enzyme indicates the presence of 3-4 independent and identical sites with a dissociation constant of 18.3 .cntdot. 10-6 M. Cu2+ binds to the enzyme at only one kind of site(s). This Cu2+ binding site(s) is characterized by a moderately ionic ligand field provived by the protein and by a tetragonal symmetry of nitrogen and/or oxygen ligands. Competition studies indicate that Mg2+ binds at these Mn2+ and Cu2+ binding sites.

关键词： f 1 -ATPase ESR Cu 2+ -binding site Mg 2+ -binding site ( M. lysodeikticus, M. luteus )

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STUDIES ON THE CYTOCHROME B6/f COMPLEX .1. CHARACTERIZATION Of THE COMPLEX SUBUNITS IN CHLAMYDOMONAS-REINHARDTII

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BIOCHIMICA ET BIOPHYSICA ACTA 1986年第2期851卷 229-238页

作者： LEMAIRE, C GIRARDBASCOU, J WOLLMAN, fA BENNOUN, P INST BIOLOGIE PHYS CHIM SERV PHOTOSYNTHESE 13 RUE PIERRE & MARIE CURIE F-75231 PARIS 05 FRANCE

We have analyzed the heme-associated peroxidase activity in thylakoid membranes from the green algae Chlamydomonas reinhardtii after electrophoresis in the presence of sodium dodecyl sulfate. Besides cytochrome f and cytochrome b6, we observed peroxidase activity in two other bands, of 34 and 11 kDa, of unknown origin. Characterization of the b6/f complex subunits was undertaken by means of a comparison of the polypeptide deficiencies in several b6/f mutants with the polypeptide content of preparations enriched in b6/f complexes. We conclude that the b6/f complex consists of five subunits. Using site-specific translation inhibitors, we show that cytochrome f, cytochrome b6 and subunit IV are of chloroplast origin, whereas the Rieske protein and probably subunit V are translated on cytoplasmic ribosomes. A model of assembly of the complex is proposed: a cytochrome moiety, comprising the subunits of chloroplast origin, is assembled in the thylakoid membranes prior to the insertion and assembly of the subunits encoded in the nuclear genome.

关键词： Cytochrome b 6 / f complex Peroxidase Thylakoid membrane Protein assembly Chloroplast biogenesis Cyt cytochrome PS Photosystem HP high potential LP low potential α antibody TMBZ 3,3′,5,5′-tetramethylbenzidine DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea PBS phosphate-buffered saline f 0 initial yield of fluorescence f max maximal yield of fluorescence

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THE DOMAIN ORGANIZATION Of THE CHLOROPLAST THYLAKOID MEMBRANE - LOCALIZATION Of PHOTOSYSTEM-I AND Of THE CYTOCHROME-B6-f COMPLEX

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BIOCHIMICA ET BIOPHYSICA ACTA 1986年第2期850卷 402-412页

作者： MELIS, A SVENSSON, P ALBERTSSON, PA UNIV LUND CTR CHEM DEPT BIOCHEM POB 124 S-22100 LUND SWEDEN

The relative distribution of chlorophyll (Chl) a and Chl b, of Photosystem I (PS I), and of the cytochrome b6-f (Cyt b6-f) complex in different subchloroplast membrane vesicles is presented. Spinach chloroplasts (Chl a/Chl b = 2.7, Chl/PS I = 435.1, Chl/Cyt f = 970:1) were fractionated by Yeda press treatment and by sonication. Counter-current distribution of the resulting thylakoid vesicles in dextran-polyethylene glycol aqueous two-phase systems yielded a laterally extended range of chloroplast thylakoid membranes without loss of chloroplast material from the initial sample. In this analysis, PS I-enriched membrane vesicles moved in the leading edge of the counter-current distribution diagram, whereas PS II-enriched vesicles remained close to the trailing edge of the counter-current distribution diagram. Vesicles of mixed composition and vesicles depleted in both PS I and PS II were isolated from intemediate positions. The Chl/PS I ratio in the various fractions approximted a hyperbolic function of the Chl a/Chl b ratio with limiting values of Chl/PS I = 190:1 attained at a Chl a/Chl b = 6 and a Chl a/Chl b = 1.67 attained when the Chl/PS I ratio approaches infinity ([PS I] = 0). Such hyperbolic distribution is consistent with the exclusive localization of PS I in stroma-exposed thylakoids and of PS II in the membrane of the grana partition region. A depletion of the Cyt b6-f complex from the membrane domain of PS I was detected (Chl a/Chl b = 5.1, Chl/PS I - 210:1, Chl/Cyt f = 1510:1). Moreover, a chloroplast thylakoid membrane was identified, distinct both from that of PS II And from that of PS I which was enriched in the Cyt b6-f complex (Chl a/Chl b = 2.67, Chl/PS I = 460:1, Chl/Cyt f = 590:1). Our results suggested that such a Cyt b6-domain is localized in the region between the appressed and the non-appressed membranes, possibly in the membrane of the fret region.

关键词： Electron transport Lateral heterogeneity Thylakoid membrane Photosystem I Cytochrome b 6 - f complex (Spinach chloroplast) Chl chlorophyll P-700 reaction center of PS I Cyt cytochrome CCD counter-current distribution Tricine N -[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine PS I, II, Photosystem I, II

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EffICIENT RECONSTITUTION Of MITOCHONDRIAL ENERGY-TRANSfER REACTIONS fROM DEPLETED MEMBRANES AND f1-ATPASE AS A fUNCTION Of THE AMOUNT Of BOUND OLIGOMYCIN SENSITIVITY-CONfERRING PROTEIN (OSCP)

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BIOCHIMICA ET BIOPHYSICA ACTA 1986年第1期852卷 55-67页

作者： PENIN, f DELEAGE, G GODINOT, C GAUTHERON, DC Laboratoire de Biologie et Technologie des Membranes du Centre National de la Recherche Scientifique Université Claude Bernard de Lyon 43 Boulevard du 11 novembre 1918 69622 Villeurbanne Cedex France

(1) Pig heart mitochondrial membranes depleted of f1 and OSCP by various treatments were analyzed for their content in .alpha. and .beta. subunits of f1 and in OSCP using monoclonal antibodies. Membrane treatments and conditions of rebinding of f1 and OSCP were optimized to reconstitute efficient NADH- and ATP-dependent proton fluxes, ATP synthesis and oligomycin-sensitive ATPase activity. (2) f1 and OSCP can be rebound independently to depleted membranes but to avoid unspecific binding of f1 to depleted membranes (ASUA) which is not efficient for ATP synthesis, f1 must be rebound before the addition of OSCP. (3) The rebinding of OSCP to depleted membranes reconstituted with f1 inhibits the ATPase activity of rebound f1, while it restores the ATP-driven proton flux measured by the quenching of ACMA fluorescence. The rebinding of OSCP also renders the ATPase activity of bound f1 sensitive to uncouplers. (4) The rebinding of OSCP alone or f1 alone, does not modify the NADH-dependent proton flux, while the rebinding of both f1 and OSCP controls this flux, inducing an inhibition of the rate of NADH oxidation. Similarly, oligomycin, which seals the f0 channel even in the absence of f1 and OSCP, inhibits the rate of NADH oxidation. (5) OSCP is required to adjust the fitting of f1 to f0 for a correct channelling of protons efficient for ATP synthesis. (6) All reconstituted energy transfer reactions rearch their optimal value for the same amount of OSCP. This amount is consistent with a stoichiometry of two OSCP per f1 in the f0-f1 complex.

关键词： Oligomycin sensitivity-conferring protein f 1 -ATPase Proton translocation ATP synthesis NADH oxidation (Pig heart mitochondria) ETP inverted submitochondrial particles f 1 nucleotide-depleted pig-heart mitochondrial ATPase OSCP oligomycin sensitivity-conferring protein ASUA particles ASU particles treated with NH 3 to remove OSCP ASU particles submitochondrial particles treated with ammonia, Sephadex and urea to remove f 1 ATPase adenosine-5′-triphosphatase (EC 3.6.1.3) ACMA 9-amino-6-chloro-2-methoxy-acridine IODOGEN 1,3,4,6-tetrachloro-3α,6α-diphenylglycoluril NEM N -ethylmaleimide fCCP carbonylcyanide p -trifluoromethoxyphenylhydrazone EDTA ethylenediaminetetraacetic acid Tris 2-amino-2-hydroxymethylpropane-1,3-diol Mes 4-morpholineethanesulphonic acid Hepes 4-(2-hydroxyethyl)-1-piperazineethanesulphonic acid P i inorganic phosphate

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