Abstract:
:A hypothesis is proposed to explain the function of Cl(-) in activating the oxygenevolving complex (OEC) of photosystem II (PS II), based on the results of recent (35)Cl-NMR studies. The putative mechanism involves Cl(-) binding to two types of sites. An intrinsic site is suggested to be composed of three histidyl residues (His 332 and His 337 from D1 and His 337 D2). It is proposed that Cl(-) binding to this site accelerates the abstraction of H(+) from water by raising the pKa's of the histidine imidazole groups. Cl(-) binding also stimulates the transfer of H(+) from this intrinsic site to a set of extrinsic sites on the 33 kD extrinsic polypeptide. The extrinsic Cl(-) binding sites are suggested to involve four protein domains that are linked together by salt-bridge contacts. Chloride and H(+) donated from the intrinsic site attack these intramolecular salt-bridges in a defined sequence, thereby exposing previously inaccessible Cl(-) and H(+) binding sites and stimulating the oxidation of water. This hypothesis also proposes a possible structure for the Mn active site within the D1/D2 complex. Specific amino-acid residues that are likely to participate as Mn lignads are identified on the lumenal portions of the D1 and D2 proteins that are different from those in the L and M subunits of photosynthetic bacteria; the choice of these residues is based on the metal coordination chemistry of these residues, their location within the polypeptide chain, the regularity of their spacing, and their conservation through evolution. The catalytic Mn-binding residues are suggested to be D-61, E-65, E-92, E-98, D-103; D-308, E-329, E-342 and E-333 in D1, and H-62, E-70, H-88, E-97, D-101; E-313, D-334, E-338 and E-345 in D2. Finally, this hypothesis identifies sites on both D2 and the 33 kD extrinsic polypeptide that might be involved in high- and low-affinity Ca(2+) binding.
journal_name
Photosynth Resjournal_title
Photosynthesis researchauthors
Coleman WJ,Govindjeedoi
10.1007/BF00029400subject
Has Abstractpub_date
1987-09-01 00:00:00pages
199-223issue
3eissn
0166-8595issn
1573-5079journal_volume
13pub_type
杂志文章abstract::We present the wavelength dependence of homogeneous holewidths of persistent spectral holes burnt in O2-evolving Photosystem II core complexes isolated from spinach, in the temperature range 2.5-8 K. The data supports the assignment that those chlorophylls which undergo persistent spectral hole-burning are specific CP...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-004-7927-6
更新日期:2005-06-01 00:00:00
abstract::The linear dichroism of Photosystem I particles containing 10 chlorophylls per P700 has been investigated at 10 K. The particles were oriented by uniaxial squeezing of polyacrylamide gels. The oxidation state of P700 was altered either by incubation of the gels with redox mediators or by low temperature illumination. ...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00047172
更新日期:1989-07-01 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::Species in the Laxa and Grandia groups of the genus Panicum are adapted to low, wet areas of tropical and subtropical America. Panicum milioides is a species with C3 photosynthesis and low apparent photorespiration and has been classified as a C3/C4 intermediate. Other species in the Laxa group are C3 with normal phot...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00024189
更新日期:1986-01-01 00:00:00
abstract::Time-resolved (TR) infrared (IR) spectroscopy in the nanosecond to second timescale has been extensively used, in the last 30 years, in the study of photosynthetic systems. Interesting results have also been obtained at lower time resolution (minutes or even hours). In this review, we first describe the used technique...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-016-0305-3
更新日期:2017-02-01 00:00:00
abstract::Oxygen may enhance CO2-saturated photosynthesis in intact leaves, which display the Warburg effect when illuminated at the current atmospheric level of CO2 and O2, of about 350 microl l(-1) and 21%, respectively. The magnitude of the stimulation depends on irradiance. The K(M)(O2) of the stimulation is 128 microM (10....
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-006-9050-3
更新日期:2006-06-01 00:00:00
abstract::The light-harvesting complex (LHC) of higher plants isolated using Triton X-100 has been studied during its transformation into a monomeric form known as CPII. The change was accomplished by gradually increasing the concentration of the detergent, sodium dodecyl sulfate (SDS). Changes in the red spectral region of the...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00029727
更新日期:1986-01-01 00:00:00
abstract::The unicellular green alga Chlamydomonas reinhardtii acclimates to low-CO2 (LC) conditions by actively transporting inorganic carbon (Ci) into the cell, resulting in an increase in photosynthetic efficiency. This mechanism is called the carbon-concentrating mechanism (CCM), and soluble protein LCIB is essential for th...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-013-9963-6
更新日期:2014-09-01 00:00:00
abstract::The photophysical and photochemical reactions, after light absorption by a photosynthetic pigment-protein complex, are among the fastest events in biology, taking place on timescales ranging from tens of femtoseconds to a few nanoseconds. The advent of ultrafast laser systems that produce pulses with femtosecond durat...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-009-9454-y
更新日期:2009-08-01 00:00:00
abstract::Two portable instruments, designed to evaluate epidermal UV screening in leaves, were compared: the Dualex and the UV-A-PAM fluorimeter. Both instruments excite chlorophyll fluorescence at the same UV wavelengths but reference excitation is in the red and the blue spectral range in the former and the latter fluorimete...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-007-9135-7
更新日期:2007-07-01 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::Acaryochloris marina is a unique cyanobacterium that contains chlorophyll (Chl) d as a major pigment. Because Chl d has smaller excitation energy than Chl a used in ordinary photosynthetic organisms, the energetics of the photosystems of A. marina have been the subject of interest. It was previously shown that the red...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-014-0073-x
更新日期:2015-08-01 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::We have used antibodies generated against synthetic peptides to determine the topology of the 43 kD chlorophyll a binding protein (CP 43) of Photosystem II. Based on the pattern of proteolytic fragments detected (on western blots) by peptide specific antibodies, a six transmembrane span topological model, with the ami...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00019041
更新日期:1994-04-01 00:00:00
abstract::MOA-stilbene is known to be a specific inhibitor of the Qo site of mammalian cytochrome bc 1 complex. We show that it also binds to the chloroplast cytochrome bf complex. Binding to the reduced enzyme induces a red-shift of the Soret and visible absorption bands of the haems b. Steady state and single turnover experim...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00029819
更新日期:1992-12-01 00:00:00
abstract::This contribution gives a brief survey of the short history since the discovery of the aerobic phototrophic bacteria to focus on a general evolutionary scenario. Most of the citations are of reviews that have covered the earlier literature and to which the reader is directed at appropriate places in the following text...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1023/A:1020493518379
更新日期:2002-01-01 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::Macroalgae occur in the marine benthos from the upper intertidal to depths of more than 200 m, contributing up to 1 Pg C per year to global primary productivity. Freshwater macroalgae are mainly green (Chlorophyta) with some red (Rhodophyta) and a small contribution of brown (Phaeophyceae) algae, while in the ocean al...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-012-9768-z
更新日期:2012-09-01 00:00:00
abstract::The potential role of foliar carbon export features in the acclimation of photosynthetic capacity to differences and changes in light environment was evaluated. These features included apoplastic vs. symplastic phloem loading, density of loading veins, plasmodesmatal frequency in intermediary cells, and the ratio of l...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-006-9123-3
更新日期:2007-11-01 00:00:00
abstract::Chlorophyll (Chl) is an essential component of the photosynthetic apparatus. Embedded into Chl-binding proteins, Chl molecules play a central role in light harvesting and charge separation within the photosystems. It is critical for the photosynthetic cell to not only ensure the synthesis of a sufficient amount of new...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-013-9797-2
更新日期:2014-02-01 00:00:00
abstract::Significance of molecular crowding in grana thylakoids of higher plants on photosystem II function was studied by 'titrating' the naturally high protein density by fusing unilamellar liposomes of the native lipid mixture with isolated grana membranes (BBY). The incorporation of lipids was monitored by equilibrium dens...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-007-9253-2
更新日期:2008-02-01 00:00:00
abstract::C3 carbon fixation has a bad reputation, primarily because it is associated with photorespiration, a biochemical pathway thought to waste a substantial amount of the carbohydrate produced in a plant. This review presents evidence collected over nearly a century that (1) Rubisco when associated with Mn(2+) generates ad...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-014-0056-y
更新日期:2015-02-01 00:00:00
abstract::The effect of acetate metabolism on the light energy distribution between the two photosystems, on the PS II/PS I stoichiometry and on the expression of psbA and psbB and psaA genes was investigated in the green alga, Chlamydobotrys stellata during autotrophic (CO(2)), mixotrophic (CO(2) plus acetate) and photoheterot...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1023/A:1010650532693
更新日期:2000-01-01 00:00:00
abstract::The crystallization of a given protein is a hard task being even more complicated when the protein shows a hydrophobic behavior. In the case of photosynthetic proteins, the difficulty of the experiments increased due to the high light sensitivity. Aqueous solutions of photosystem II core complex (OEC PSII) of Pisum sa...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-007-9131-y
更新日期:2006-12-01 00:00:00
abstract::An immunological method for quantitative determination of photosynthetic fructose-1,6-bisphosphatase in crude extracts of leaves is proposed. It is based on the ELISA technique, and offers two modifications. A non-competitive technique has a higher sensitivity and is the right option for samples of low fructose-1,6-bi...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00032710
更新日期:1987-01-01 00:00:00
abstract::Dan Arnon, Bob Whatley, Mary Belle Allen, and their colleagues, were the first to obtain evidence for 'complete photosynthesis by isolated chloroplasts' albeit at rates which were 1% or less of those displayed by the intact leaf. By the 1960s, partly in the hope of confirming full functionality, there was a perceived ...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1023/A:1024962328483
更新日期:2003-01-01 00:00:00
abstract::The absorption spectra of two light harvesting complexes from higher plants, CP29 and LHC II, have been analysed in the Soret region in order to obtain a description in terms of the absorption spectra of the individual pigments. This information is of great practical use when applying spectroscopic techniques to the s...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1023/A:1006455230379
更新日期:2000-01-01 00:00:00
abstract::Modified forms of the D1 protein with deletions in lumen-exposed regions, were constructed in the cyanobacterium Synechocystis 6803 using site-directed mutagenesis. Integration and stability of the mutated D1 proteins in the thylakoid membrane were studied by immunoblot and pulse-chase analyses. It was found that in Δ...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00117663
更新日期:1996-08-01 00:00:00
abstract::Photoacclimation by strains of Haslea "blue" diatom species H. ostrearia and H. silbo sp. nov. ined. was investigated with rapid light curves and induction-recovery curves using fast repetition rate fluorescence. Cultures were grown to exponential phase under 50 µmol m-2 s-1 photosynthetic available radiation (PAR) an...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-018-0508-x
更新日期:2018-09-01 00:00:00
abstract::Modulation of the efficiency with which leaves convert absorbed light to photochemical energy [intrinsic efficiency of open photosystem II (PSII) centers, as the ratio of variable to maximal chlorophyll fluorescence] as well as leaf xanthophyll composition (interconversions of the xanthophyll cycle pigments violaxanth...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-012-9761-6
更新日期:2012-09-01 00:00:00