plastoquinone/hypoxia

Neonatal hypoxia⁻ischemia is one of the main causes of mortality and disability of newborns. To study the mechanisms of neonatal brain cell damage, we used a model of neonatal hypoxia⁻ischemia in seven-day-old rats, by annealing of the common carotid artery with subsequent hypoxia of 8% oxygen. We

In the absence of PSII, non-photochemical reduction of plastoquinones (PQs) occurs following NADH or NADPH addition in thylakoid membranes of the green alga Chlamydomonas reinhardtii. The nature of the enzyme involved in this reaction has been investigated in vitro by measuring chlorophyll

Phylloquinone (PhQ), or vitamin K1 , is an essential electron carrier (A1 ) in photosystem I (PSI). In the green alga Chlamydomonas reinhardtii, which is a model organism for the study of photosynthesis, a detailed characterization of the pathway is missing with only one mutant deficient for MEND

To identify optimal conditions for renewable hydrogen production from sunlight and water we have studied transcriptional changes of the hoxEFUYH genes encoding the bidirectional hydrogenase in the cyanobacterium Synechocystis PCC 6803. Transcript abundance detection by real time polymerase chain

Under sulfur deprivation conditions, the green alga Chlamydomonas reinhardtii produces hydrogen in the light in a sustainable manner thanks to the contribution of two pathways, direct and indirect. In the direct pathway, photosystem II (PSII) supplies electrons to hydrogenase through the

Limited evidence up to now indicates low linear photosynthetic electron flow and CO(2) assimilation rates in non-foliar chloroplasts. In this investigation, we used chlorophyll fluorescence techniques to locate possible limiting steps in photosystem function in exposed, non-stressed green fruits

BACKGROUND In the violaxanthin (V) cycle, V is de-epoxidized to zeaxanthin (Z) when strong light or light combined with other stressors lead to an overexcitation of photosystems. However, plants can also suffer stress in darkness and recent reports have shown that dehydration triggers

While photosynthetic linear electron flow produces both ATP and NADPH, cyclic electron flow (CEF) around photosystem I (PSI) and cytochrome b6f generates only ATP. CEF is thus essential to balance the supply of ATP and NADPH for carbon fixation; however, it remains unclear how the system tunes the

Cyclic electron flow around photosystem I drives additional proton pumping into the thylakoid lumen, which enhances the protective non-photochemical quenching and increases ATP synthesis. It involves several pathways activated independently. In whole barley leaves, P700 oxidation under far-red

BACKGROUND Under low O2 concentration (hypoxia) and low light, Chlamydomonas cells can produce H2 gas in nutrient-replete conditions. This process is hindered by the presence of O2, which inactivates the [FeFe]-hydrogenase enzyme responsible for H2 gas production shifting algal cultures back to

The relative contributions of the PSII-dependent and Nda2-dependent pathways for H₂ photoproduction were investigated in the green microalga Chlamydomonas reinhardtii after suphur-deprivation. For this purpose, H₂ gas production was compared for wild-type and Nda2-deficient cells with or without

BACKGROUND Plants often suffer from hypoxic stress during waterlogging and hydroponic culturing. This study investigated the response of cucumber (Cucumis sativus L.) plant growth parameters, leaf photosynthesis, chlorophyll fluorescence, fast chlorophyll a fluorescence transient (OJIP), and fruit