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INfLUENCE Of EfRAPEPTIN, AUROVERTIN AND CITREOVIRIDIN ON THE MITOCHONDRIAL ADENOSINE-TRIPHOSPHATASE fROM TRYPANOSOMA-CRUZI

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MOLECULAR AND BIOCHEMICAL PARASITOLOGY 1981年第3期3卷 143-155页

作者： DEfLOMBAUM, MAC STOPPANI, AOM Instituto de Química Biológica Facultad de Medicina Universidad de Buenos Aires Paraguay 2155 1121-Buenos Aires Argentina

Steady-state velocity studies using a substrate regenerating system showed that efrapeptin, citreoviridin and aurovertin inhibit both membrane-bound and soluble mitochondrial ATPase (coupling factor f1) from Trypanosoma cruzi. Maximal inhibitions of ATP hydrolysis produced by efrapeptin and citreoviridin were 100-93%, while the maximal inhibition produced by aurovertin was 40%. Half-maximal inhibitory concentrations decreased in the order citreoviridin greater than aurovertin greater than efrapeptin. Dissociation constants (KD) for the inhibitor-f1 complex were 81 nM (efrapeptin), 6.6 muM (aurovertin) and 40 muM (citreoviridin); KD values for the membrane-bound f1 were 2-4 fold higher than for soluble f1. Representation of efrapeptin inhibition data in the Hill form yielded straight lines (n = 1) while the same representation of citreoviridin inhibition yielded concave down plots. In contrast to the immediate effect of citreoviridin and aurovertin, efrapeptin inhibition was time-dependent. The onset of inhibition, which was pseudo-first-order with respect to efrapeptin, indicated that ATP may promote the binding of efrapeptin to the enzyme. The kinetics of ATP hydrolysis by T. cruzi ATPase as a function MgATP concentration could be explained by the presence of two substrate sites on the enzyme, interacting in such a way that the binding and catalytic events at one site were conformationally linked to the events at the other site, as with the mammalian ATPase. When the antibiotics were assayed at increasing substrate concentrations, efrapeptin produced a linear, mixed-type inhibition whereas citreoviridin produced a parabolic noncompetitive-type inhibition. The aurovertin effect was unusual since the extent of inhibition was greater at high substrate concentrations. Maximal concentrations of all the assayed antibiotics linearized the biphasic double reciprocal plot of control ATPase activity. Comparison of T. cruzi and mammalian f1 responses to the assayed antibiotic

关键词： Trypanosoma cruzi Mitochondrial adenosine triphosphatase Coupling factor f 1 Efrapeptin Aurovertin Citreoviridin

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PROPERTIES Of THYLAKOIDS AND THYLAKOID PARTICLES DERIVED fROM STRUCTURALLY DIffERENT CHLOROPLASTS

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BIOCHIMICA ET BIOPHYSICA ACTA 1981年第1期638卷 12-21页

作者： HOMANN, PH LIU, YY FLORIDA STATE UNIV INST MOLEC BIOPHYS TALLAHASSEE FL 32306 USA

Structurally and functionally different tobacco [Nicotiana tabacum] chloroplasts were subjected to digitonin treatment and subsequent fractional centrifugation. The light-harvesting chlorophyll a/chlorophyll b-protein complex was enriched in the most dense fraction regardless of the presence of grana in the original preparation. Evidently, isolated thylakoid membranes and fragments which contain sufficient light-harvesting protein may, under appropriate ionic conditions, form aggregates even when they originate from unstacked thylakoid systems. Comparative studies of fluorescence properties and polypeptide composition of the thylakoids suggest that the light-harvesting protein does not contribute significantly to the fluorescence spectrum of isolated chloroplasts as long as this protein is intimately associated with the photosystem II (PS II) pigment-protein complex responsible for the 685 nm emission. While the PS II-deficient mutant chloroplasts of the variegated tobacco cv. NC 95 lacked both the 685 nm fluorescence component and 2 or 3 PS II proteins, 1 of these proteins was very prominent in these chlorophyll b-deficient mutant thylakoids which also displayed an intense 685 nm fluorescence peak. This correlation supports the contention that a 45 kdalton polypeptide is an apoprotein of pigments associated with the PS II reaction center.

关键词： Chlorophyll fluorescence Thylakoid Photosystem II Light-harvesting complex (Tobacco chloroplast) Chl chlorophyll f fluorescence peak,used in conjunction with number indicating wavelength JWB tobacco variety John Williams Broadleaf LHCP light-harvesting Chl a b- protein complex NC yellow yellow leaf areas of the variegated tobacco mutant derived from variety NC 95 PS photosystem SDS sodium dodecyl sulfate Tricine N -tris(hydroxymethyl)methylglycine DCIP 2,6-dichlorophenolindophenol

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AN HRP STUDY ON THE DISTRIBUTION Of ALL NUCLEI INNERVATING THE SUPRAOPTIC NUCLEUS IN THE RAT-BRAIN

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ACTA HISTOCHEMICA 1981年第2期69卷 274-&页

作者： IIJIMA, K OGAWA, T AKITA UNIV SCH MEDDEPT PHYSIOLAKITA 010JAPAN

Detailed histochemical studies have been performed on the distribution of the nuclei innervating the supraoptic nucleus (SO) in the whole brain after horseradish peroxidase (HRP) injections through fine glass micropipettes (2 to 8 micrograms ) into the SO of 39 Wistar strain rats. The chromatogenic reaction was carried out according to the Mesulam's (1976) No. 8 procedure. Successful HRP injections resulted in labeling in various regions of the brain. The following conclusions were drawn from the analysis of these successful cases. All the nuclei of the subthalamus and posthypothalamus innervate the SO whereas only a few neurons of the hypothalamic arcuate and ventromedial nuclei probably send axons to it. The afferent monoaminergic fibers arise largely from the B7 and B8, and to a certain extent from the A6 and A10 cell groups. The septum, diagonal band nucleus and amygdala project directly to the SO while the olfactory tubercle and pyriform cortex may not. The mesencephalic central gray has a high possibility to project directly to it. The possibility that the hippocampus sends axons to the SO remains to be fully proven. A few small multipolar cells clearly revealed by the test in the SO should be non-secretory intercalated neurons.

关键词： A10 Linear nucleus SM Medullary stria AR Hypothalamic arcuate nucleus SO Supraoptic nucleus AVT Ventral tegmental area TCC Trunk of the corpus callosum B7 Dorsal raphe nucleus TO Optic tract B8 Median raphe nucleus TUL Cortical part of the olfactory tubercle CA Anterior commissure TULI Inner part of the olfactory tubercle CAI Internal capsule VM Hypothalamic ventromedial nucleus CC Cerebral crus Vm Motor nucleus of the trigeminal nerve CG Mesencephalic central gray ZI Zona incerta f fornix am Medial amygdaloid nucleus fOP Optic fascicle ac Cortical amygdaloid nucleus fH Hippocampal fimbria cp Caudate-putamen complex fLM Medial longitudinal fascicle ha Anterior hypothalamic nucleus fMT Mamillothalamic fascicle hdm Hypothalamic dorsomedial nucleus GP Globus pallidus hl Lateral hypothalamic nucleus H forel's field H 2 hp Posterior hypothalamic nucleus HI Hippocampus proper lh Lateral habenular nucleus LC Locus coeruleus pd Dorsal premamillary nucleus LGB Lateral geniculate body pol Lateral preoptic nucleus LM Medial lemniscus pom Medial preoptic nucleus MB Marginal nucleus of the superior cerebellar peduncle pv Ventral premamillary nucleus pvr Periventricular thalamic nucleus MfB Medial forebrain bundle r Red nucleus MT Mesencephalic tr. nucleus of the trigeminal nerve sl Lateral septal nucleus sm Medial septal nucleus NRC Reticular formation of the pons sum Supramamillary nucleus Pcs Superior cerebellar peduncle td Diagonal band nucleus PG Pontine central gray tm Medial thalamic nucleus PVN Paraventricular nucleus tv Ventral thalamic nucleus RM Large raphe nucleus

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ENZYMATIC PHOSPHORYLATION Of ACYCLIC NUCLEOSIDE ANALOGS AND CORRELATIONS WITH ANTIHERPETIC ACTIVITIES

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BIOCHEMICAL PHARMACOLOGY 1981年第22期30卷 3071-3077页

作者： KELLER, PM fYfE, JA BEAUCHAMP, L LUBBERS, CM fURMAN, PA SCHAEffER, HJ ELION, GB Wellcome Res. Lab. Research Triangle Park NC 27709 United States

The inhibitor and substrate specificities of deoxythymidine (dThd) kinase purified from herpes simplex virus (HSV Type 1) were studied. A number of nucleosides and nucleoside analogs were phosphorylated by the virus coded enzyme. These included several compounds structurally related to 9-(2-hydroxyethoxymethyl)guanine (acyclovir), a potent inhibitor of HSV replication. Some contained guanine with 9-substituents differing from those of acyclovir by methylene additions, methylene and thioether substitutions for the ether oxygen, and branching on the distal side of the ether oxygen. Others were various 2-substituted 6-hydroxypurines with the 9-(2-hydroxyethoxymethyl) substituent. A limitation of the specificity of the enzyme with guanine derivatives was the lack of phosphorylation of any derivative with an acyclic moiety branched on the proximal side of the ether oxygen. Many of the compounds that were phosphorylated were subsequently found to inhibit HSV replication. Such compounds apparently inhibited HSV replication via the same route of activation previously described for acyclovir. Moreover, several compounds not phosphorylated by the enzyme did not inhibit replication. Some other acyclic nucleoside analogs that were phosphorylated were not good antivirals, indicating that phosphorylation catalyzed by the HSV dThd kinase was not sufficient for inhibition of viral replication to occur. These results evidently emphasize the importance of the specificity of cellular kinases and the HSV DNA polymerase to the mechanism of antiviral activity. The dThd kinase from Vero cells was also purified. With this host cell enzyme, kinetic constants of known antiviral compounds were determined and compared to those of dThd (relative V''max;K''m: dThd (100;1.3 .mu.M), 5-iodo-2''-deoxyuridine (87;1.8 mM), 5-trifluoromethyl-2''-deoxyuridine (91;1.2 .mu.M), 5-bromo-2''-deoxycytidine (5;580 .mu.M) and 9-.beta.-D-arabinofuransyolthymine (23;2300 .mu.M). None of the purine acyclic nucleos

关键词： acyclic any substitution for the carbohydrate moiety of a nucleoside analog which is not a closed ring acyclovir 9-(2-hydroxyethoxymethyl)guanine araT 9-β- d -arabinofuranosylthymine araG 9-β- d -arabinofuranosylguanine 8-azaguanine 5-amino-7-oxo- v -triazolo[4,5- d ]pyrimidine BrdCyd 5-bromo-2′-deoxycytidine IdUrd 5-iodo-2′-deoxyuridine f 3 TdR 5-trifluoromethyl-2′-deoxyuridine HSV-1 herpes simplex virus type 1 BHK baby hamster kidney BSA bovine serum albumin and PEP phosphoenol pyruvate

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SCHISTOSOMA-MANSONI - MODULATION Of SCHISTOSOMULAR LIPID-COMPOSITION BY SERUM

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MOLECULAR AND BIOCHEMICAL PARASITOLOGY 1981年第4期3卷 239-252页

作者： RUMJANEK, fD MCLAREN, DJ NATL INST MED RES DIV PARASITOL LONDON NW7 1AA ENGLAND

Human serum and fetal calf serum are compared in terms of their ability to modify the biochemical and immunological properties of the schistosomular surface. Artificially transformed schistosomula were incubated in the presence of serum for 24 h and then radioiodinated using the chloramine T method. With this method only lipids are labeled. fetal calf serum produces a net loss of lipids from the schistosomula, particularly of mono- and diglycerides. Human serum promotes not only a loss of mono- and diglycerides, but also a substantial uptake of cholesterol and triglycerides. Schistosomula recovered from the lungs of mice could also be labeled and contained, besides triglycerides, an increased amount of cholesterol esters. The modulation of surface lipids in worms cultured with human serum correlates with the observation that such schistosomula develop significantly greater protection against eosinophil-mediated cytotoxicity in vitro than do individuals incubated with fetal calf serum. Schistosomula cultured in the presence of either human serum or fetal calf serum develop the same degree of protection against complement-dependent lethal antibody;this result indicates that resistance against complement-mediated damage may be independent of the uptake of cholesterol and/or triglycerides, and might involve only limited alterations in the surface configuration of the schistosomulum.

关键词： Schistosomula Surface lipids Radioiodination Protection Cytotoxic assays ELAC Earle's lactalbumin hydrolysate PBS phosphate-buffered saline fCS foetal calf serum HS human serum NRS normal rat serum IRS immune serum NGPS normal guinea pig serum f fresh hi heat-inactivated

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PHOTOREGULATION Of K+-ATPASE INVITRO BY RED AND fAR RED-LIGHT IN EXTRACTS fROM CUCUMBER HYPOCOTYLS

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ZEITSCHRIfT fUR PfLANZENPHYSIOLOGIE 1981年第4期102卷 283-292页

作者： THOMAS, B TULL, SE Division of Physiology and Chemistry Glasshouse Crops Research Institute Worthing Road Littlehampton West Sussex BN16 3PU U.K.

Particulate material from cucumber hypocotyls was purified by differential centrifugation and agarose gel chromatography. The fraction was heterogeneous in nature and contained both phytochrome and ATPase activity. The latter consisted of at least 2 different components, a non-specific acid phosphatase and a potassium stimulated ATPase (K+-ATPase). The K+-ATPase appeared to be strongly inhibited by Ca+2 and was subject to photoregulation by red and far red light (R and f) in vitro. f caused an increase in Km for ATP and this was reversible by subsequent R. No significant effect on Vmax was caused by the light treatments. Photoregulation of ATPase in vitro occurred only if R was given in vivo prior to extraction. The effect of R in vivo was reversible by f indicating that this also was a phytochrome response. The acid phosphatase activity was not subject to photoregulaton but its presence prevented further characterization of the K+-ATPase and its photoregulation. Phytochrome may indirectly affect K+-ATPase by affecting membrane permeability and substrate availability.

关键词： Cucumis sativus L. ATPase phytochrome membranes BSA bovine serum albumin EDTA ethylene diamine-tetraacetic acid ATP adenosine 5'-triphosphate ATPase ATP phosphohydrolase (E.C. 3.6.1.3) R red light f far red light Pr red absorbing form of phytochrome Pfr far red absorbing form of phytochrome MOPS morpholinopropanesulphonic acid E.R. endoplasmic reticulum

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WATER-BALANCE AND RENAL-fUNCTION IN THE AUSTRALIAN DESERT RODENT NOTOMYS-ALEXIS - THE EffECT Of DIET ON WATER TURNOVER RATE, GLOMERULAR-fILTRATION RATE, RENAL PLASMA-fLOW AND RENAL BLOOD-fLOW

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COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY 1981年第3期68卷 405-410页

作者： HEWITT, S WHELDRAKE, Jf BAUDINETTE, RV School of Biological Sciences Flinders University of South Australia Bedford Park South Australia 5042

Water turnover rate, glomerular filtration rate and renal plasma and blood flow rates have been measured in individuals of the Australian desert rodent N. alexis under conditions of acute and chronic water deprivation and high nitrogen diet. When these parameters are compared with values predicted allometrically, the extreme ability of the species to conserve water is apparent only in those groups subjected to water stress. While a reversible reduction in renal function is evident upon water deprivation, the major factor in water conservation under these conditions is the renal reabsorption of water at a post-filtration stage.

关键词： fW animals maintained on finch seed and water ad libitum f animals maintained on finch seed alone S animals maintained on soya beans with limited water GfR glomerular filtration rate ERPf estimated renal plasma flow ERBf estimated renal blood flow

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CHANGES IN THE RAT HEPATIC MIXED-fUNCTION OXIDASE SYSTEM ASSOCIATED WITH CHRONIC ETHANOL VAPOR INHALATION

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BIOCHEMICAL PHARMACOLOGY 1981年第6期30卷 595-600页

作者： MORGAN, ET DEVINE, M SKETT, P UNIV GLASGOW DEPT PHARMACOL GLASGOW G12 8QQ SCOTLAND

Chronic ethanol vapor inhalation by rats increased hepatic microsomal aniline hydroxylase activity, increasing the turnover number and decreasing Km. Activity of ethanol-induced microsomes toward other substrates was also examined. Increased aniline hydroxylase activity as a result of ethanol treatment was attributed to an increase in a form of cytochrome P-450 with a high specific activity toward aniline. Since the ethanol effect on aniline hydroxylation disappeared 24 h after treatment was discontinued, a high rate of turnover of this enzyme was deduced. Dimethylsulfoxide (56 mM) produced a reverse type I spectral change in ethanol-induced but not in control microsomes. This was due to a change in the spin state of the cytochrome P-450 in these microsomes. Acetone added to the incubation produced an increased rate of aniline hydroxylation by microsomes from control and ethanol-induced rats. The difference between the rate of aniline hydroxylation by control microsomes and the rate by ethanol-induced microsomes was abolished at higher acetone concentrations.

关键词： P-450, hepatic microsomal cytochrome P-450 P-450EI, ethanol-induced P-450 PB, phenobarbital 3-MC, 3-methylcholanthrene DMSO, dimethylsulfoxide SDS, sodium dodecylsulfate BNf, β-naphthoflavone f p T , NADPH-cytochrome P-450 reductase

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ON THE ELECTRO-OSMOTIC fLOW IN A SATURATED POROUS-MEDIUM

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INTERNATIONAL JOURNAL Of ENGINEERING SCIENCE 1981年第7期19卷 915-928页

作者： AURIAULT, JL STRZELECKI, T POLITECH WROCLAW INST GEOTECHWROCLAWPOLAND

Electro-osmosis in a saturated porous rigid medium is studied by both theoretical and experimental approach. Relationships giving liquid and electrical coupled macroscopic flows are obtained from the homogeneization method. They point out possible non symmetrical cross effects that explain deviations from Onsager reciprocal relations. Experiments on a kaolinite are reported which exhibit an important non symmetrical coupling.

关键词： b ion mobility e electric charge of aquo-ions g gravity acceleration j current density j r relative current density k Boltzmann constant l characteristic length of the micro-structure n outward normal to surfaces p pressure in the liquid q electric charge density q f electric charge density in the liquid v velocity of the fluid x microscopic space variable y microscopic space variable D diffusion coefficient E electric field L macroscopic characteristic length L αβ , L̂ αβ second order tensors coefficients of the linear macroscopic flow laws R radius of the aquo-ion Ta absolute temperature V electric potential γ amplitude of the small perturbation δ Kronecker symbol δ Γ surface charge density on Γ ϵ small parameter characterizing the medium structure μ viscosity of the liquid ρ l specific mass of the liquid σ conductivitv of the ion-containina fluid Γ solid-liquid-contact surface θ dielectric tensor Ω period of the micro-structure Ω s , Ω f solid, liquid part of Ω

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A QUANTITATIVE-DETERMINATION fOR THE DETECTION Of IMMUNOGLOBULIN (IGG) ON THE SURfACE Of PLATELETS

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HUMAN IMMUNOLOGY 1981年第4期3卷 379-379页

作者： ORSINI, f GREGORY, S DALE, M fITZPATRICK, J COHEN, E NEW YORK STATE DEPT HLTH ROSWELL PK MEM INSTBUFFALONY 14263

A sensitive method for the quantitation of IgG on platelets had not been demonstrated until 1975, when Dixon, Rosse, and Ebbert described a quantitative antiglobulin consumption test useful in detecting platelet associated IgG (N Engl J Med 292:230, 1975). A modification of that technique has rendered the assay reproducible and removed the need for daily repetition of a standard IgG titration curve for quantitation. This modification utilizes 1-ethyl-3-3(dimethylaminopropyl)carbodiimide HCl (ECDI) (Sigma, E-7750), in place of chromic chloride, as a coupling agent for attaching IgG (Miles 64-145) to sheep cells (SRC), used as indicator cells. The ECDI consistently couples IgG to SRC and does not subject the SRC to sporadic spontaneous lysis, as does chromic chloride. This modification permits the detection of IgG on platelets (Direct Test), or in sera (Indirect Test) by incubation of a washed platelet pool with sera in vitro, and testing as in the Direct Test. Normal values of 0.01-1.56 and 0.14-1.6 femtograms (f) per platelet have been obtained for the Direct and Indirect Tests, respectively. In six cases of suspected ITP, values ranged 12.0-221.0 f and 2.9-37.6 f for the Direct and Indirect Tests, respectively. In conclusion, in disease states or other abnormal situations, quantities of IgG can be detected that are not usually present on the platelets of normal subjects.

关键词： ALA antileukocyte antibody AML acute myelogenous leukemia APA antiplatelet antibody ECDI 1-ethyl-3-(3 dimethylaminopropyl) carbodiimide EDTA (ethylenedinitrilo)tetraacetic acid dipotassium salt f femtogram (1 × 10 −5 g) ITP idiopathic thrombocytopenia PBS phosphate buffered saline SRC sheep red cells

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