Abstract：
:The Mg-dechelating activity of extracts of Chenopodium album (goosefoot) was investigated using an artificial substrate, chlorophyllin a. The activity was measured spectrophotometrically by the formation of a reaction product, pheophorbin a (Mg-free chlorin), after release of the central Mg. The Mg-releasing protein was highly purified by successive DEAE, Butyl and HW-55 chromatographies. The molecular weight of the purified protein was 20 k by gel filtration. The protein showed a broad, but single, pH optimum at 7.5. The K (m) value for chlorophyllin a was 95.1 nM at pH 7.5. The Mg-releasing protein was not active with chlorophyllide a, a native substrate, although it was active with Zn-chlorophyllin a. Similar results were obtained from horseradish peroxidase. Only a small molecular weight, metal-chelating substance (MCS) had Mg-dechelating activity for the native substrate. An inhibitor study showed involvement of radicals in the Mg-dechelation of the Mg-releasing protein. The purified Mg-releasing protein showed neither peroxidase activity nor absorption bands in the visible region, and this indicates that the Mg-releasing protein is clearly distinct from horseradish peroxidase, which is a heme-containing protein. A likely conclusion is that the Mg-releasing protein and horseradish peroxidase are not involved in the Mg-dechelation in the degradation pathway of chlorophylls. The relevance of the participation of MCS in Mg-dechelation in the breakdown of chlorophylls (Chls) is also discussed.
journal_name
Photosynth Resjournal_title
Photosynthesis researchauthors
Suzuki T,Shioi Ydoi
10.1023/A:1020915812770subject
Has Abstractpub_date
2002-01-01 00:00:00pages
217-23issue
2eissn
0166-8595issn
1573-5079journal_volume
74pub_type
杂志文章abstract：:Photosynthetic acclimation varies among species, which likely reveals variations at the biochemical level in the pathways that constitute carbon assimilation and energy transfer. Local adaptation and phenotypic plasticity affect the environmental response of photosynthesis. Phenotypic plasticity allows for a wide arra...
journal_title：Photosynthesis research
pub_type： 杂志文章,评审
doi：10.1007/s11120-013-9816-3
更新日期：2014-02-01 00:00:00
abstract：:Intra- and inter-specific variation in CO2 assimilation rate (A) in Triticum spp. is well documented for reproductive growth stages. Research was conducted to characterize early vegetative photosynthetic variation in a diverse set of cultivated hexaploid wheat (T. aestivum L.) germplasm and in wild tetraploid (T. dico...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00034120
更新日期：1989-05-01 00:00:00
abstract：:Light activation of phosphoenolpyruvate carboxylase from the leaves of the C4 plant Setaria verticillata (L.) is more pronounced at low CO2 levels. The 2-fold activation observed at physiological ambient CO2 becomes 3.64-fold at 5 μL/L and completely abolished above 700 μL/L. When the stomata close under the influence...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00034834
更新日期：1988-11-01 00:00:00
abstract：:Photoinhibition of Photosystem II (PSII) in lincomycin-treated leaves begins as a first-order reaction, but fluorescence measurements have suggested that after prolonged illumination, the number of active PSII centres stabilizes to 15-20% of control. The stabilization has been interpreted to indicate that photoinhibit...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-009-9496-1
更新日期：2010-01-01 00:00:00
abstract：:Chlorophyll f is a photosynthetic pigment that was discovered in 2010. In this study, we present investigations on spectral and dynamic characteristics of singlet-excited and triplet states of Chl f with the application of ultrafast time-resolved absorption and fluorescence spectroscopies. The pigment was studied at r...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-014-9981-z
更新日期：2014-07-01 00:00:00
abstract：:The chlorophyll-protein and polypeptide composition of manganese deficient and control sugar beet thylakoids was examined using three different detergent-electrophoresis systems. On a per chlorophyll basis, manganese deficiency reduced the amounts of CPa complex (separated by sodium dodecylsulfate (SDS)-polyacrylamide...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00014677
更新日期：1986-01-01 00:00:00
abstract：:A three-dimensional model of the core proteins D1 and D2, including the cofactors, that form the Photosystem II reaction centre of pea (Pisum sativum), has been generated. This model was built with a rule-based computer modelling system using the information from the crystal structures of the photosynthetic reaction c...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00033446
更新日期：1992-11-01 00:00:00
abstract：:The storage of light energy in chemical form through photosynthesis is the key process underlying life as we know it. To utilize photosynthates efficiently as structural materials or as fuel to drive endergonic processes, they have to be transported from where they are produced to where they are needed. In this primer...
journal_title：Photosynthesis research
pub_type： 杂志文章,评审
doi：10.1007/s11120-013-9867-5
更新日期：2013-11-01 00:00:00
abstract：:A non-competitive enzyme-linked immunosorbent assay (ELISA) which enables detection of as little as 0.1 ng cytochrome f in leaf extracts has been developed. No evidence for specific or non-specific interference by proteins other than cytochrome f was found. The assay was applied to a comparative study of age-related c...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00032649
更新日期：1990-04-01 00:00:00
abstract：:The effect of desiccation and rehydration on the function of Photosystem II has been studied in the desiccation tolerant lichen Cladonia convoluta by thermoluminescence. We have shown that in functional fully hydrated thalli thermoluminescence signals can be observed from the recombination of the S2(3)QB (-) (B band),...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00041010
更新日期：1996-05-01 00:00:00
abstract：:The kinetic and spectroscopic properties of the secondary electron acceptor A1 were determined by flash absorption spectroscopy at room and cryogenic temperatures in a Photosystem I (PS I) core devoid of the iron-sulfur clusters FX, FB and FA. It was shown earlier (Warren, P.V., Golbeck, J.H. and Warden, J.T. (1993) B...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00015559
更新日期：1995-09-01 00:00:00
abstract：:Light-induced reaction dynamics of isolated photosynthetic membranes obtained from wild-type (WT) and reaction center (RC)-subunit deletion strains SPUHK1 (an H-subunit deletion mutant) and SK Delta LM (an (L+M) deletion mutant) of the purple non-sulphur bacterium Rhodospirillum rubrum have been investigated by femtos...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-009-9520-5
更新日期：2010-03-01 00:00:00
abstract：:Thylakoids are complex sub-organellar membrane systems whose role in photosynthesis makes them critical to life. Thylakoids require the coordinated expression of both nuclear- and plastid-encoded proteins to allow rapid response to changing environmental conditions. Transport of cytoplasmically synthesized proteins to...
journal_title：Photosynthesis research
pub_type： 杂志文章,评审
doi：10.1007/s11120-018-0567-z
更新日期：2018-12-01 00:00:00
abstract：:The current study confirmed earlier conclusions regarding differential ozone (O(3)) tolerances of two soybean cultivars, Essex and Forrest, and evaluated antioxidant enzyme activities of these two varieties based on their performance under environmentally relevant, elevated O(3) conditions. The experiment was conducte...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1023/A:1026500911237
更新日期：2000-01-01 00:00:00
abstract：:We present a theoretical study of excitation dynamics in the chlorosome antenna complex of green photosynthetic bacteria based on a recently proposed model for the molecular assembly. Our model for the excitation energy transfer (EET) throughout the antenna combines a stochastic time propagation of the excitonic wave ...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-014-9978-7
更新日期：2014-06-01 00:00:00
abstract：:Soybean [Glycine max (L.) Merr. cv. Williams 82 and A3127] plants were grown in the field under long-term soil moisture deficit and irrigation to determine the effects of severe drought stress on the photosynthetic capacity of soybean leaves. Afternoon leaf water potentials, stomatal conductances, intercellular CO2 co...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00051735
更新日期：1990-07-01 00:00:00
abstract：:A comparative study of photosystem II complexes isolated from tobacco (Nicotiana tabacum L. cv. John William's Broadleaf) which contains normal stacked thylakoid membranes, and from two chlorophyll deficient tobacco mutants (Su/su and Su/su var. Aurea) which have low stacked grana or essentially unstacked thylakoids w...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00032264
更新日期：1987-01-01 00:00:00
abstract：:Treatment of lyophilized thylakoid membranes of the thermophilic cyanobacterium Synechococcus sp. with n-heptane for 6 h resulted in marked changes in the pattern of photosystem I reaction center complexes resolved by sodium dodecylsulfate-polyacrylamide gel electrophoresis. CP1-a, which consists of two large subunits...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00117671
更新日期：1987-01-01 00:00:00
abstract：:Cyanobacteria, algae, and plants produce dioxygen from water. Driven and clocked by light quanta, the catalytic Mn(4)Ca Tyrosine centre accumulates four oxidizing equivalents before it abstracts four electrons from water and liberates dioxygen and protons. Intermediates of this reaction cascade are short-lived (<100 m...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-008-9321-2
更新日期：2008-10-01 00:00:00
abstract：:Using 77 K chlorophyll a (Chl a) fluorescence spectra in vivo, the development was studied of Photosystems II (PS II) and I (PS I) during greening of barley under intermittent light followed by continuous light at low (LI, 50 mumol m(-2) s(-1)) and high (HI, 1000 mumol m(-2) s(-1)) irradiances. The greening at HI inte...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1023/A:1020943107318
更新日期：2002-01-01 00:00:00
abstract：:The picture presently emerging from studies on the mechanism of photosystem II electron transport is discussed. The reactions involved in excitation trapping, charge separation and stabilization of the charge pair in the reaction center, followed by the reactions with the substrates, plastoquinone reduction and water ...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00032785
更新日期：1985-01-01 00:00:00
abstract：:The study of the light-harvesting complex II (LHC-II) phosphatase activity has been difficult due to the membrane association of its substrate. Thylakoid membranes labeled with [γ-(32)P]ATP were incubated with chymotrypsin, releasing phosphopeptides which served as labeled substrates for LHC-II phosphatase. Utilizing ...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00018301
更新日期：1995-05-01 00:00:00
abstract：:The effects of protein phosphorylation and cation depletion on the electron transport rate and fluorescence emission characteristics of photosystem I at two stages of chloroplast development in light-grown wheat leaves are examined. The light-harvesting chlorophyll a/b protein complex associated with photosystem I (LH...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00030071
更新日期：1990-01-01 00:00:00
abstract：:The 3- and 7-formyl groups of chlorophyll-d (Chl-d) and bacteriochlorophyll-e (BChl-e), respectively, were regioselectively labeled with an isotopically stable oxygen-18 (¹⁸O) atom to give 3¹-¹⁸O-labeled Chl-d and 7¹-¹⁸O-labeled BChl-e (ca. 90% ¹⁸O) by exchanging the carbonyl oxygen atoms in the presence of acidic H₂ ...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-010-9590-4
更新日期：2010-09-01 00:00:00
abstract：:In studies on photosynthetic systems it is common practice to interpret the results of time-resolved fluorescence experiments on the basis of compartmental, or target, models. Each compartment represents a group of molecules with similar fluorescence characteristics. In cases of practical interest, the members of each...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00014883
更新日期：1996-11-01 00:00:00
abstract：:Effect of chemical oxidation by ferricyanide on bacteriochlorophyll a (BChl a) in the Fenna-Matthews-Olson protein (FMO) was studied using absorbance and fluorescence spectroscopy at ambient and cryogenic temperatures. Partially selective oxidation of pigments bound to the antenna complex was achieved and the probable...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-013-9878-2
更新日期：2013-09-01 00:00:00
abstract：:The electron transport rates of photosystems II and I, amounts of electron carriers, coupling factor activity and photosynthetic rates were investigated in thylakoids isolated from pea plants grown under a wide range of light intensities (16 h light-8 h dark). The electron transport rates of PS II and PS I, as partial...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00028525
更新日期：1984-06-01 00:00:00
abstract：:A correlated influence of cation concentration and excitation energy level on PS II Abbreviations: AMPD = 2-amino-2-methyl-1,3-propanediol; DCIP = 2-6 dichlorophenol indophenol; DCIPH2 = DCIP in reduced state; DCIPr = rate of DCIP-reduction; DCMU = 3-(3,4 dichlorophenyl)1-1 dimethyl-urea; Fv = variable fluorescence; F...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/BF00018228
更新日期：1980-06-01 00:00:00
abstract：:Although it has been believed that wild-type plants are capable of protecting photosystem I (PSI) under high light, our previous study indicates that PSI is sensitive to high light in the shade-established tree species Psychotria rubra. However, the underlying physiological mechanisms are unclear. In this study, we ex...
journal_title：Photosynthesis research
pub_type： 杂志文章
doi：10.1007/s11120-016-0275-5
更新日期：2016-07-01 00:00:00
abstract：:Joan Mary Anderson, known to most people as Jan, was born on May 12, 1932 in Dunedin, New Zealand. She died on August 28, 2015 in Canberra, Australia. To celebrate her life, we present here a brief biography, some comments on her discoveries in photosynthesis during a career spanning more than half a century, and remi...
journal_title：Photosynthesis research
pub_type： 传,历史文章,杂志文章
doi：10.1007/s11120-016-0287-1
更新日期：2016-08-01 00:00:00
