Sentences with word «photosystem»

Our initial quantitative measurements followed changes in the maximum efficiency of photosystem II, expressed as Fv / Fm [23].

Working at SLAC's Linac Coherent Light Source (LCLS), the world's most powerful x-ray laser, the researchers were able to take detailed «snapshots» of the four photon - step cycle for water oxidation in photosystem II, a large protein complex in green plants.

By engineering an atomically precise film so that it can support chemical reactions without damaging sensitive semiconductors, the researchers managed to satisfy contradictory needs for artificial photosystems.

In his original work, Zhang was able to enlist a complex of molecules known as photosystem - I (PS - I), the tiny structures within plant cells that carry out photosynthesis.

They identified six proteins linked to a complex called photosystem II (PSII), which forms a cluster of nine genes — slr0144 to slr0152.

A, Micro - compartment for linear PET (solid arrows): electrons flow from photosystem II (PSII), through plastoqui - none (PQ) and the cytochrome b6f (Cytb6f) complex to PSI, where they are donated to Fd and used by FNR to reduce NADP +.

Photo - oxidation of water by photosystem II is responsible for most of the oxygen in Earth's atmosphere.

Postdoctoral researcher Louise Lassalle (from left), research scientist Jan Kern and research assistant Lacey Douthit work on growing cyanobacteria to isolate photosystem II proteins in a Berkeley Lab bioreactor.

A femtosecond X-ray pulse from an X-ray free electron laser intersecting a droplet that contains photosystem II crystals, the protein extracted and crystallized from cyanobacteria.

Using this configuration, the researchers could run photosystems continuously for three days — potentially longer — when such systems would normally fail in mere seconds.

(B) Changes in maximum efficiency of photosystem II expressed as quantitative Fv / Fm values shown graphically or (C) Spatially.

Our previously described synthetic de-greening gene circuit shows a threshold - like response through generation of reactive oxygen species and photosystem disruption [7].

«Using femtosecond x-ray pulses for the simultaneous collection of both x-ray diffraction (XRD) and x-ray emission spectroscopy (XES) data at room temperature, we have gone around the four - step catalytic cycle of photosynthetic water oxidation in photosystem II.

The program focuses on development of transition - metal complexes that are inspired by the natural photosynthetic enzymes such as nitrogenases, hydrogenases, and the oxygen - evolving complex of photosystem II with the goal of designing catalysts that are chemically stable, active, and highly selective for specific chemical targets.

The study authors noted that while this is an important milestone, there are many more steps needed before a commercially viable artificial photosystem is ready for deployment.

The experiments, led by the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), are helping researchers narrow down the process by which the protein, called photosystem II, uses light energy to split water and create oxygen.

At LCLS, the researchers first illuminated their crystal samples with green photons to trigger the photosynthetic reactions in photosystem II.

Conclusions about the structure of the photosystem II reaction center from plants are drawn, and aspects of membrane protein structure are discussed.

The images, published today in the journal Nature, provide the first high - resolution 3 - D view of photosystem II in action, a feat accomplished by using unimaginably fast X-ray free - electron laser (XFEL) pulses from the Linac Coherent Light Source (LCLS) at SLAC National Accelerator Laboratory, a DOE Office of Science User Facility.

Software algorithms developed by Sauter, Paul Adams (also of the Molecular Biophysics and Integrated Bioimaging Division at Berkeley Lab), and their respective groups were then used to translate the diffraction readings into the 3 - D rendering of photosystem II.

Structure of the oxygen evolving complex in photosystem II in a light - activated state.

«But the stages of photosystem II do not proceed at freezing temperatures.

This represents a major advance towards the real time characterization of the formation of the oxygen molecule in photosystem II, and has yielded information that should prove useful for designing artificial solar - energy based devices to split water.»

At the core of photosystem II is a manganese - calcium (Mn4Ca) metalloenzyme complex that when energized by solar photons catalyzes a four photon - step cycle of oxidation states (S0 - to - S3) that ultimately yields molecular oxygen.

«In order for an artificial photosystem to be viable, we need to be able to make it once, deploy it, and have it last for 20 or more years without repairing it,» said study principal investigator Ian Sharp, head of materials integration and interface science research at JCAP.

Figure 4 shows three distinct determinations for plant response to the ligand: visual, quantitative changes to the maximum efficiency of photosystem II (Fv / Fm) and with quantitative RT - PCR.

We measured the ligand induced response using four different methods: quantitative measurements of GUS, visual changes, quantitative changes in photosystem II efficiency (Fv / Fm), and with quantitative RT - PCR.

X-ray free electron laser and mass spectrometric studies into the mechanism of water oxidation in photosystem II

Using the world's most powerful x-ray laser, an international collaboration led by Berkeley Lab researchers took femtosecond «snapshots» of water oxidation in photosystem II, the only known biological system able to harness sunlight for splitting the water molecule.

Blocking the Q (B)- binding site of photosystem II by tenuazonic acid, a non-host-specific toxin of Alternaria alternata, activates singlet oxygen - mediated and EXECUTER - dependent signalling in Arabidopsis

Their paper, titled «Independent initiation of primary electron transfer in the two branches of the photosystem I reaction center,» appears in this week's online Early Edition of the Proceedings of the National Academy of Sciences (PNAS).

Their work focuses on one of two photosynthesis complexes, known as photosystem I (PSI; the other is photosystem II, PSII).

The symbionts residing closer to the surface may be better adapted to high irradiance by making proteins that protect against too much ultra violet light or by modifying their photosystem.