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Elevated atmospheric CO2 improved Sorghum plant water status by ameliorating the adverse effects of drought
○ The interactive effects of atmospheric CO 2 concentration and soil-water content on grain sorghum (Sorghum bicolor) are reported here. ○ Sorghum plants were exposed to ambient (control) andExpand
Universality of energy and electron transfer processes in photosystem I.
The difference spectrum associated with Ao reduction appears to contain contributions from more than a single chlorophyll pigment, which is similar to that obtained from measurements using detergent-isolated PS I particles from spinach and Chlamydomonas reinhardtii. Expand
P700: the primary electron donor of photosystem I.
EPR studies of P700(+*) in frozen solution and single crystals indicate a large asymmetry in the electron spin and charge distribution towards one Chl of the dimer, suggesting that the unpaired electron would predominantly reside on the Chl a. Expand
Influence of the axial ligands on the spectral properties of P700 of photosystem I: a study of site-directed mutants.
The data provide convincing evidence that the unpaired electron in the cation radical and the triplet state of P700 are mainly localized on the Chl a of the dimer which is axially coordinated by His(B656). Expand
Excitation Dynamics in the Core Antenna of PS I from Chlamydomonas reinhardtii CC 2696 at Room Temperature
Photosystem I particles from a eukaryotic organism, the green alga Chlamydomonas reinhardtii CC 2696, were studied by transient hole-burning spectroscopy at room temperature. Global analysis of theExpand
Photosystem II energy use, non-photochemical quenching and the xanthophyll cycle in Sorghum bicolor grown under drought and free-air CO2 enrichment (FACE) conditions
It is concluded that elevated Ca enhances photochemical light energy usage in C 4 photosynthesis during drought and/ or midday conditions and decreases non-photochemical quenching (NPQ) during periods of limited water availability. Expand
Increased Accumulation of Carbohydrates and Decreased Photosynthetic Gene Transcript Levels in Wheat Grown at an Elevated CO2 Concentration in the Field
The results suggest that, whereas the hypothesis that photosynthetic genes by increased soluble carbohydrate concentrations may explain acclimation of photosynthesis to elevated CO2 concentration may hold well in model laboratory systems, many other factors modified its significance in this field wheat crop. Expand
Bidirectional electron transfer in photosystem I: accumulation of A0- in A-side or B-side mutants of the axial ligand to chlorophyll A0.
Ultrafast transient absorbance measurements show that the (A(0)(-) - A(0)) difference signal accumulates in the MH(A684) and MH(B664) mutants under neutral conditions, demonstrating that electron transfer between A( 0)(-) and A(1) is blocked or significantly slowed. Expand
Species-specific Differences of the Spectroscopic Properties of P700
The results indicate structural differences among PS I from higher plants, algae, and cyanobacteria and give further insight into specific protein-cofactor interactions contributing to the optical spectra. Expand
Replacement of the methionine axial ligand to the primary electron acceptor A0 slows the A0- reoxidation dynamics in photosystem I.
It is shown that the replacement of either methionine with histidine in the PSI of the unicellular green alga Chlamydomonas reinhardtii resulted in accumulation of A(0)(-) (in 300-ps time scale), suggesting that both the PsaA and PsaB branches are active, and support the model of equivalent electron transfer along both cofactor branches in Photosystem I. Expand