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1.
Dark-grown cells of a mutant strain of Chlorella regularis containedchlorophyll a and protochlorophyll, phytyl ester of protochlorophyllide.Under illumination, protochlorophyll was quantitatively anddirectly converted into chlorophyll a. The photoconversion wasdependent on light intensity and temperature and proceeded ina cell-free preparation. The pathway of chlorophyll formation found in the mutant cellsis entirely different from that from protochlorophyllide byway of chlorophyllide a, which is generally observed in greenplants. 1Present address: Division of Biology, Medical College of Miyazaki,Miyazaki 889-16, Japan. 2Present address: Division of Environmental Biology, The NationalInstitute for Environmental Studies, Ibaragi 300-21, Japan. (Received October 24, 1975; )  相似文献   

2.
Rice (Oryza sativa L.) seedlings were germinated under waterin darkness for 5 or 6 days (submerged seedlings) and then inair for 1 day. Control seedlings were germinated in air, indarkness, for 5 or 6 days (aerobic seedlings). Changes in levelsof antioxidants and in the extent of oxidative damage afterexposure of submerged seedlings to air were studied. -Tocopherol,which inhibits lipid peroxidation, was present in submergedseedlings at about 3 times the level found in aerobically growncontrols, and higher levels than in controls were maintainedfor 24 h after transfer of the seedlings to air. Products oflipid peroxidation were present at a one-third of the levelsfound in aerobic controls, and their levels increased aftertransfer to air. However, these levels remained lower than thosein aerobic controls even after 24 h of contact with air. Carotenoids,which are considered to protect chlorophyllous compounds againstphotooxidation, were not found in submerged seedlings, but theirlevels increased after exposure of the seedlings to air. Lightat an intensity that did not cause photooxidative damage tochlorophyllous compounds in aerobic controls induced photobleachingof these compounds in submerged seedlings during the early stagesof adaptation to air. However, the extent of photobleachingdiminished as adaptation to air proceeded, and photobleachingwas no longer detected after 24 h of adaptation to air. Thus,the system for protection of cellular membranes from lipid peroxidationin the post-hypoxic phase appeared already to exist in submergedseedlings. However, the system for protection of pigments fromphotobleaching was poorly developed in submerged seedlings andwas fully active only after 24 h of adaptation to air. 1Present address: Department of Biology, Faculty of Science,Shizuoka University Shizuoka, 422 Japan 2Present address: Research Institute for Bioresources, OkayamaUniversity, Kurashiki, 710 Japan  相似文献   

3.
A cDNA for the phytochrome of the fern Adiantum capillus-venerisL. was cloned and sequenced. The deduced phytochrome is 50{smalltilde}55% identical to phytochromes of seed plants, and 68%identical to Selaginella phytochrome. Regions resemble thosein previously characterized phytochromes from ferns, lower plantsand seed plants. 3Present address: Yamanouchi Pharmaceutical Co., Ltd., 21 Miyukigaoka,Tsukuba-shi, Ibaraki, 305 Japan 4Present address: Plant Growth Regulation Laboratory, The Instituteof Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako-shi,Saitama, 351-01 Japan 5Present address: Advanced Research Laboratory, Hitachi, Ltd.,Hatoyama, Saitama, 350-03 Japan  相似文献   

4.
Ethylene stimulated the elongation of intact rice (Oryza sativaL.) coleoptiles in which endogenous growth had been stoppedcompletely by decapitation and red light. p-Chlorophenoxyisobutyricacid slightly inhibited endogenous growth, but not the ethyleneinduced growth. Thus, ethylene could stimulate the elongationof coleoptiles in which the auxin level was considered to bevery low. 1 Present address: Institute for Agricultural Research, TohokuUniversity, Katahira, Sendai 980, Japan. (Received February 16, 1979; )  相似文献   

5.
A synthetic substance, 4-ethoxy-l-(p-tolyl)-s-triazine-2,6(1H,3H)-dione [TA] dramatically promoted mesocotyl growth in dark-grownrice (Oryza sativa L. cv. Nato) seedlings, the optimal concentrationbeing 0.1–0.2 mM. Changes in the cell wall compositionof the rice mesocotyls were examined in relation to growth andtreatment with 0.1 mM TA. The amount of the cell wall increasedduring the elongation in control and treated mesocotyls. Particularly,TA caused a large increase in the amount of the cell wall permesocotyl but a decrease per unit length of mesocotyl. Hydrolysisof the cell wall with trifluoroacetic acid liberated xylose,glucose, arabinose, galactose, and trace amounts of rhamnose,fucose and mannose. An increase in the relative amount of xyloseand a decrease in that of glucose in the noncellulosic fractionduring growth were found in control and treated mesocotyl walls.On the 2nd day after planting when the mesocotyl emerged, TAsignificantly affected the cell wall composition; TA decreasedthe relative amount of -cellulose in the wall, and caused anincrease in the relative amount of glucose and decreases inthose of xylose and arabinose in the noncellulosic fraction. 1This paper is Part 7 in the series "Plant Growth-regulatingActivities of Isourea Derivatives and Related Compounds." (Received March 18, 1980; )  相似文献   

6.
Rice (Oryza sativa L. cv. Yamabiko) seedlings germinated underwater for 5 days contained small amounts of heme a and protohemebut no protochlorophyll(ide) [Pchl(ide)]. Levels of hemes andPchl(ide) increased rapidly upon transfer to air. When expressedin terms of fresh weight of tissue, hemes reached the levelsin aerobic controls after 24 h of contact with air, but Pchl(ide)did not. A comparison of the increases during 24-h adaptationto air in levels of heme a and Pchl(ide), which are specificto mitochondria and plastids, respectively, suggested that thedevelopment of mitochondria preceded that of plastids. The rateof synthesis of 5-aminolevulinic acid (ALA) was low in submergedseedlings, as compared to the rate in aerobic controls, butit increased during air adaptation. The sum of the amounts ofheme a, protoheme and Pchl(ide) increased in parallel with theamount of porphyrins, equivalent to the amount of ALA synthesizedduring the experimental period. When submerged seedlings thathad been pretreated with levulinic acid were exposed to air,no Pchl(ide) was formed. In contrast, Pchl(ide) accumulatedunder water when submerged seedlings were fed with ALA. Theseresults indicate that the synthesis of ALA, the limiting stepin the synthesis of Pchl(ide), is repressed under hypoxic conditions. 1 Present address: KRI International, Inc., Kyoto Research Park17, Chudoji Minami-machi, Shimogyo-ku, Kyoto, 600 Japan. 2 Present address: Research Institute for Bioresources, OkayamaUniversity, Kurashiki, 710 Japan.  相似文献   

7.
Activity staining with NADPH-nitroblue tetrazolium after native-PAGEof membrane proteins of Synechocystis PCC6803, solubilized with3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS),revealed four NAD(P)H dehydrogenase (NDH) activities; an NDHcomplex of the respiratory chain, a ferredoxin NADP+ reductase(FNR), a drgA product which oxidized both NADH and NADPH, andan uncharacterized NADH-specific enzyme. The NDH complex waspurified with anion exchange and gel filtration chromatographies.The purified complex had a molecular mass of 376 kDa and wascomposed of 9 subunits. Western analysis showed that the complexcontained the NDH-H subunit, but not NDH-A or B. The enzymereduced ferricyanide much faster than plastoquinone and usedNADPH as its prefered electron donor rather than NADH. The enzymaticactivity was inhibited by diphenyleneiodonium chloride and salicylhydroxamicacid, but not by rotenone, p-chloromercuribenzoate, N-ethylmaleimide,flavon, dicumarol, or antimycin A. These results suggest thatthe purified complex is a hydrophilic subcomplex which containsan NADPH binding site and flavin, and is dissociated from ahydrophobic subcomplex, which contains quinone binding site. 1Present address: Division of Applied Life Sciences, GraduateSchool of Agriculture, Kyoto University, Sakyo, Kyoto, 606-8502Japan 3Present address: Department of Biotechnology, Faculty of Engineering,Fukuyama University, 1 Gakuencho, Fukuyama, Hiroshima, 729-0292Japan  相似文献   

8.
Previous analysis of a transgenic tobacco line (BN1) that over-expressedrice phytochrome A (PhyA) indicated that the introduced PhyAwas spectrally and biologically active [Kay et al. (1989) PlantCell 1: 775, Nagatani et al. (1991) Proc. Natl. Acad. Sci. USA88: 5207]. In the present study, we have further investigatedresponses of the BN1 plants to light. Fluence rate dependenceanalysis of the inhibition of hypocotyl elongation indicatedthat the response is biphasic. The amplitude of the low fluencerate component increased by 2 to 3 fold in the BN1 plants comparedto the wild type. In contrast, the presence of rice PhyA didnot alter the level of chlorophyll in the BN1 seedlings grownunder the same light conditions. Ultrastructure studies showedthat chloroplasts in the BN1 plants were not significantly differentfrom those in the wild type plants, except that chloroplastsin the guard cells of the BN1 plants appeared to be more developedthan those of the wild type plants. The fluence response analysisof the potentiation of chlorophyll accumulation indicated nosignificant difference between the BN1 and the wild type plants.Thus, the introduced rice PhyA greatly influenced hypocotylelongation but did not significantly affect the greening process. 4Present address: NSFC Center for Biological Timing, Universityof Virginia Charlottesville, VA 22901, U.S.A. 5Present address: Advanced Research Laboratory, Hitachi Ltd.Hatoyama, Saitama, 350-03 Japan  相似文献   

9.
Significant leaf sheath elongation occurred within 24 hr afterapplication of 10 µg (0.67, µCi) of ent-(3H)-17-kaurenoicacid (KA) to individual seedlings of dwarf rice cv. Tan-ginbozu,but this growth was unaccompanied by production of significantlevels of radioactivity in more polar, acidic, ethyl acetate-solublemetabolites of (3H)-KA. However modest levels of radioactivityappeared in the highly water-soluble fraction by hour 24, subsequentto the most rapid phase of KA-induced growth. Growth continuedand by hour 48 was accompanied by the appearance of small amountsof radioactivity in polar, acidic products. It would appearthat KA per se, and not its metabolic products, may be responsiblefor the leaf sheath elongation noted at hour 24. On the speculation that it might be a metabolite of KA, gibberellinA14 (GA14) was applied simultaneously with (3H)-KA to individualrice seedlings. Several changes in the metabolism of 3H-KA inthe presence of GA14 were noted, and GA14 antagonized the KA-inducedsheath elongation. 1Present address: Botany Department, Rhodes University, Grahamstown,6140, South Africa. 2Present address: Crop Science Department, University of Saskatchewan,Saskatoon, Sask. S7N OWO, Canada. (Received May 12, 1975; )  相似文献   

10.
The folypolyglutamate derivatives of pea seedlings (Pisum sativumL. cv. Homesteader) were extracted in the presence of 2-mercaptoethanoland cleaved to p-aminobenzoylpolyglutamates by treatment withZn-HCl. Azo dyes were formed by reaction with naphthylethylenediamine and purified by polyacrylamide gel chromatography. p-Aminobenzoylpolyglutamateswere regenerated from these dyes by Zn treatment and then concentratedin vacuo. These derivatives were separated according to glutamylchain length by high performance liquid chromatography on WhatmanPartisil SAX columns. The folylpolyglutamates of 4 day old peacotyledons, pea leaves and isolated chloroplasts were mainlytetra- and pentaglutamates. These and folates of shorter chainlength were labelled when seeds and aerial shoots were incubatedwith p-aminobenzoate-[14C]. Labelling of the pentaglutamatewas reduced in seeds that were imbibed in the presence of 0.1mM methotrexate. Studies of cotyledon folylpolyglutamate synthetaseshowed that polyglutamate chain length was affected by incubationtime and the concentration of tetra-hydrofolate monoglutamatein the reaction system. 1Present address: Department of Biology, University of Lethbridge,Alberta, Canada T1K 3M4 2Present address: Department of Horticulture, Xiong-yue AgriculturalCollege, Xiong-yue, Liaoning Province, China (Received August 4, 1989; Accepted December 5, 1989)  相似文献   

11.
Mesophyll chloroplasts were isolated from leaves of a Na+-requiringNAD-malic enzyme type, dicotyledonous C4 plant, Amaranthus tricolorL. The chloroplasts converted pyruvate to phosphoenolpyruvateunder illumination, and the conversion was stimulated by Na+.This observation may explain the requirement for Na+ of someC4 plants. 2 Present address: Institute for Life Science Research, NihonNohyaku Co., Ltd., Kawachi-Nagano, Osaka, 586 Japan  相似文献   

12.
Deoxygibberellin C (DGC), a C/D ring-rearranged isomer of GA20,was shown to inhibit the conversion of [2,3-3H2]GA9 to [2-3H]GA4by gibberellin 3ß-hydroxylase from immature seedsof Phaseolus vulgahs. Deoxygibberellin C inhibited the promotionof growth by exogenously applied GA20 of rice (Oryza sativaL.) seedlings. Evidence is also presented that DGC is a competitiveinhibitor of the 3ß-hydroxylase from P. vulgaris.However, DGC only weakly inhibited the conversion catalyzedby the 3ß-hydroxylase from Cucurbita maxima at highconcentrations, and it did not inhibit the promotion of growthby exogenously applied GA9 of cucumber (Cucumis sativus) seedlings.These results suggest that the 3ß-hydroxylases fromP. vulgaris and C. maxima have different structural requirementswith respect to their substrates. 16-Deoxo-DGC also inhibitedcatalysis of the same conversion by 3ß-hydroxylasefrom P. vulgaris, and it slightly inhibited the conversion catalyzedby the enzyme from C. maxima. Application of 16-deoxo-DGC causedthe promotion of the growth of seedlings of both rice and cucumber. 3 Present address: Genetic Engineering Center, Korea Instituteof Science and Technology, Daejeon 305–606, Korea 4 Present address: Department of Agricultural Chemistry, UtsunomiyaUniversity, Utsunomiya-shi, Tochigi, 321 Japan (Received September 25, 1990; Accepted December 17, 1990)  相似文献   

13.
A high-affinity binding site for N-acetylchitooligosac-chlarideelicitor was found to localize in the plasma membrane from suspension-culturedrice cells. Binding kinetics as well as the specificity of thisbinding site corresponded well with the behavior of the ricecells to the editor. These characteristics suggest that thebinding site represents a functional receptor for N-acetylchitooligosaccharideelicitor in rice. 2Present address: Okinawa Prefectural Livestock ExperimentalStation, 2009-5 Shoshi, Nakijin-son, Okinawa, 905-04 Japan. 3Present address: School of Hygiene and Public Health, The JohnsHopkins University, 615 North Wolfe Street, Baltimore, Maryland,21205 U.S.A. 4Present address: University of Tenessee, Microbiology, knoxville,Tennessee, 37996 U.S.A.  相似文献   

14.
In a search for callus-inducing compounds for indica rice thatare superior in this regard to 2,4-dichlorophenoxyacetic acid(2,4-D), we tested 13 derivatives of phenoxyacetic acids, namely,mono- and di- chloro-, mononitro- and 4-halogeno-substitutedphenoxyacetic acids for their ability to stimulate the inductionof calluses from mature seeds of rice (Oryza sativa L. cv. Chiemchanh). Five analogues of benzoic acid were also tested. Thecallus-forming ability and the optimal concentration for inductionof calluses were differed from compound to compound. The optimal concentration for callus induction of 4-fluorophenoxyaceticacid (4FPA) was relatively high (250 µM), but its callus-formingactivity was stronger than that of 2,4-D, even when comparedwith 2,4-D at its optimal concentration (50 µM). 4FPA-inducedcalluses retained their regenerative ability for at least 15months with 9 subcultures, while calluses induced by 2,4-D losttheir regenerative ability after 3 subcultures. 4FPA-induced calluses showed higher regenerative ability thandid calluses induced by 2,4-D, in almost all of 20 varietiesof indica tested, including three indica-japonica hybrids. 3Present address: Kibun Co.Ltd., Ginza, Tokyo, 104 Japan 4Present address: Hyogo Agricultural Research Institute, Kasai,Hyogo, 679-01 Japan (Received October 25, 1989; Accepted May 17, 1990)  相似文献   

15.
The effects of Na application on growth and nitrate reductaseactivity of seven C4 plant species, Zea mays, Echinochloa crus-galli,Panicum miliaceum, Panicum coloratum, Panicum dichotomiflorum,Panicum maximum and Chloris gayana were studied. Except forZ. mays and P. miliaceum, Na application enhanced growth significantly,and concurrent increases in nitrate reductase activities weredetected in Panicum coloratum, Panicum dichotomiflorum, Panicummaximum and Chloris gayana. 1Present address: International Research Institute, Ciba GeigyJapan Ltd., Takarazuka, Hyogo 665, Japan. 2Present address: Photobiology Lab., Research Institute forFood Science, Kyoto Univ., Uji, Kyoto 611, Japan. (Received May 2, 1988; Accepted August 22, 1988)  相似文献   

16.
The pattern for primary products of CO2-fixation and the chloroplaststructure of Amaranthus retrqflexus L., a species which incorporatescarbon dioxide into C4 dicarboxylic acids as the primary productof photosynthesis, were compared in various chlorophyll containingtissues,i.e., foliage leaves, stems, cotyledons and pale-greencallus induced from stem pith. Despite some morphological differencesin these assimilatory tissues, malate and aspartate were identifiedas the major compounds labelled during a 10 sec fixation of14CO2 in all tissues. Whereas, aspartate was the major componentin C4-dicarboxylic acids formed in foliage leaves, malate predominatedas the primary product in stems, cotyledons and the pale-greencallus. The percentage of 14C-radioactivity incorporated intoPGA and sugar-P esters increased and 14C-sucrose was detectedin the prolonged fixation of 14CO2 in the light, not only infoliage leaves, but also in stems and cotyledons. 1 This work was supported by a Grant for Scientific ResearchNo. 58813, from the Ministry of Education, Japan. 2 Present address: Institute of Applied Microbiology, Universityof Tokyo, Tokyo, Japan. 3 Present address: Department of Biochemistry, University ofGeorgia, Athens 30601. Georgia, U. S. A. (Received July 10, 1971; )  相似文献   

17.
The effects of phytic acid, myo-inositol hexaphosphoric acid,in the induction and growth of rice seed callus were studied.Phytic acid was substituted for myo-inositol in the inductionof the callus and preferable effects were shown on the growthof the callus. 1Present address: Hyogo Agricultural Experiment Station, Akashi,Hyogo, Japan (Received June 30, 1970; )  相似文献   

18.
Tentoxin strongly inhibited the ATPase activity of isolatedcoupling factor 1 (AF1) from the cyanobacterium Anacystis nidulans,with 50% inhibition occurring at 0.3 µM. When thylakoidsfrom A. nidulans were preincubated with 0.3 µM tentoxinfor 30 min, photophosphorylation was inhibited by 50%. Measurementsof fluorescence from 9-aminoacridine indicated that tentoxininhibited the utilization of the proton gradient by ATP formationin thylakoids. These results indicate that tentoxin is a strongenergy-transfer inhibitor of photophosphorylation in A. nidulans.Tentoxin decreased the level of ATP in intact cells both inthe light and in darkness, its effects being much stronger inthe dark. Tentoxin at 50 µM strongly inhibited the growthof the cells. 3Present address: Corporate Research and Development Laboratory,Tonen Co. 1-3-1 Nishi-tsurugaoka, Ohi-machi, Saitama, 354 Japan 4Present address: Technology and Engineering Laboratories, AjinomotoCo., Inc. Suzuki-cho 1, Kawasaki, 210 Japan  相似文献   

19.
20.
Phosphoenolpyruvate carboxylase (PEPC) [EC 4.1.1.31 [EC] ] of plantsundergoes regulatory phosphorylation in response to light ornutritional conditions. However, the nature of protein kinase(s)for this phosphorylation has not yet been fully elucidated.We separated a Ca2+-requiring protein kinase from Ca2+-independentone, both of which can phosphorylate maize leaf PEPC and characterizedthe former kinase after partial purification. Several linesof evidence indicated that the kinase is one of the characteristicCa2+-dependent but calmodulin-independent protein kinase (CDPK).Although the Mr, of native CDPK was estimated to be about 100kDa by gel permeation chromatography, in situ phosphorylationassay of CDPK in a SDS-polyacrylamide gel revealed that thesubunit has an Mr of about 50 kDa suggesting dimer formationor association with other protein(s). Several kinetic parameterswere also obtained using PEPC as a substrate. Although the CDPKshowed an ability of regulatory phosphorylation (Ser-15 in maizePEPC), no significant desensitization to feedback inhibitor,malate, could be observed presumably due to low extent of phosphorylation.The kinase was not specific to PEPC but phosphorylated a varietyof synthetic peptides. The possible physiological role of thiskinase was discussed. 1Present address: NEOS Central Research Laboratory, 1-1 Ohike-machi,Kosei-cho, Shiga, 520-3213 Japan. 2Present address: Chugai Pharmaceutical Co., Ltd., 1-135 Komakado,Gotemba, 412-0038 Japan. 4N.O. and N.Y. contributed equally to this work.  相似文献   

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