Concepts of photochemical damage of Photosystem II and the role of excessive excitation

Zavafer, Alonso; Mancilla, Cristian

doi:10.1016/j.jphotochemrev.2021.100421

Cited by 47 publications

(28 citation statements)

References 137 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…When growing in exposed microhabitats photosynthetic organisms tend to absorb more light than they can use for fixing carbon, which can result in reductions in photosynthetic activity, often termed “photoinhibition” that will eventually reduce growth. Most authors believe that photoinhibition occurs when this excess energy results in the production of reactive oxygen species (ROS) [ 1 , 2 ]. ROS can cause lipid peroxidation or damage the D1 and D2 proteins in the reaction centre of PSII [ 3 ].…”

Section: Introductionmentioning

confidence: 99%

Melanisation in Boreal Lichens Is Accompanied by Variable Changes in Non-Photochemical Quenching

Ndhlovu

Solhaug

Minibayeva

et al. 2022

Plants

View full text Add to dashboard Cite

Lichens often grow in microhabitats where they absorb more light than they can use for fixing carbon, and this excess energy can cause the formation of harmful reactive oxygen species (ROS). Lichen mycobionts can reduce ROS formation by synthesizing light-screening pigments such as melanins in the upper cortex, while the photobionts can dissipate excess energy radiationlessly using non-photochemical quenching (NPQ). An inherent problem with using fluorimetry techniques to compare NPQ in pale and melanised thalli is that NPQ is normally measured through a variously pigmented upper cortex. Here we used a dissection technique to remove the lower cortices and medullas of Lobaria pulmonaria and Crocodia aurata and then measure NPQ from the underside of the thallus. Results confirmed that NPQ can be satisfactorily assessed with a standard fluorimeter by taking measurement from above using intact thalli. However, photobionts from the bottom of the photobiont layer tend to have slightly lower rates of PSII activity and lower NPQ than those at the top, i.e., display mild “shade” characteristics. Analysis of pale and melanised thalli of other species indicates that NPQ in melanised thalli can be higher, similar or lower than pale thalli, probably depending on the light history of the microhabitat and presence of other tolerance mechanisms.

show abstract

Section: Introductionmentioning

confidence: 99%

Melanisation in Boreal Lichens Is Accompanied by Variable Changes in Non-Photochemical Quenching

Ndhlovu

Solhaug

Minibayeva

et al. 2022

Plants

View full text Add to dashboard Cite

show abstract

“…In some cases, under MiDS and low light (LL) conditions, photosynthetic activity and, particularly, electron transport rate (ETR) and NADP + reduction are preserved, but under high light (HL) conditions, an imbalance between light energy capture and photochemical energy use appears, leading to a decrease in ETR, which leads to a high level of energy dissipation as heat to prevent the formation of reactive oxygen species (ROS) [29][30][31]. Consequently, under DS the absorbed light energy exceeds what it can be used and, thus, it can damage the photosynthetic apparatus, with photosystem II (PSII) being particularly exposed to damage [13,[32][33][34][35]. The light-harvesting, excitation transfer, charge separation and electron transfer in PSII are the essential reactions of photosynthesis and, consequently, principally regulate its total efficiency [36].…”

Section: Introductionmentioning

confidence: 99%

Leaf Age-Dependent Photosystem II Photochemistry and Oxidative Stress Responses to Drought Stress in Arabidopsis thaliana Are Modulated by Flavonoid Accumulation

Sperdouli

Moustaka

Ouzounidou³

et al. 2021

Molecules

View full text Add to dashboard Cite

We investigated flavonoid accumulation and lipid peroxidation in young leaves (YL) and mature leaves (ML) of Arabidopsis thaliana plants, whose watering stopped 24 h before sampling, characterized as onset of drought stress (OnDS), six days before sampling, characterized as mild drought stress (MiDS), and ten days before sampling, characterized as moderate drought stress (MoDS). The response to drought stress (DS) of photosystem II (PSII) photochemistry, in both leaf types, was evaluated by estimating the allocation of absorbed light to photochemistry (ΦPSII), to heat dissipation by regulated non-photochemical energy loss (ΦNPQ) and to non-regulated energy dissipated in PSII (ΦNO). Young leaves were better protected at MoDS than ML leaves, by having higher concentration of flavonoids that promote acclimation of YL PSII photochemistry to MoDS, showing lower lipid peroxidation and excitation pressure (1 − qp). Young leaves at MoDS possessed lower 1 − qp values and lower excess excitation energy (EXC), not only compared to MoDS ML, but even to MiDS YL. They also possessed a higher capacity to maintain low ΦNO, suggesting a lower singlet oxygen (1O2) generation. Our results highlight that leaves of different developmental stage may display different responses to DS, due to differential accumulation of metabolites, and imply that PSII photochemistry in Arabidopsis thaliana may not show a dose dependent DS response.

show abstract

“…Drought stress reduces photosynthesis by decreasing CO 2 availability through increased resistance to CO 2 diffusion from stomata, disturbs either biochemical, photochemical or both, activity and increases leaf membrane lipid peroxidation [19][20][21][22][23][24][25]. Under drought stress the absorbed light energy exceeds what can be used for photochemistry and thus excess accumulation of reactive oxygen species (ROS) occurs, that can damage the chloroplast, with photosystem II (PSII) being particularly exposed to damage [25][26][27][28][29]. However, overexcitation of PSII can be prevented by dissipation of excess excitation energy as heat, a procedure that is termed non-photochemical quenching (NPQ), and classically is estimated by chlorophyll a fluorescence analysis [25,[30][31][32].…”

Section: Introductionmentioning

confidence: 99%

Harnessing Chlorophyll Fluorescence for Phenotyping Analysis of Wild and Cultivated Tomato for High Photochemical Efficiency under Water Deficit for Climate Change Resilience

Sperdouli¹,

Moustakas

2021

Climate

View full text Add to dashboard Cite

Fluctuations of the weather conditions, due to global climate change, greatly influence plant growth and development, eventually affecting crop yield and quality, but also plant survival. Since water shortage is one of the key risks for the future of agriculture, exploring the capability of crop species to grow with limited water is therefore fundamental. By using chlorophyll fluorescence analysis, we evaluated the responses of wild tomato accession Solanum pennellii LA0716, Solanum lycopersicum cv. Μ82, the introgression line IL12-4 (from cv. M82 Χ LA0716), and the Greek tomato cultivars cv. Santorini and cv. Zakinthos, to moderate drought stress (MoDS) and severe drought stress (SDS), in order to identify the minimum irrigation level for efficient photosynthetic performance. Agronomic traits (plant height, number of leaves and root/shoot biomass), relative water content (RWC), and lipid peroxidation, were also measured. Under almost 50% deficit irrigation, S. pennellii exhibited an enhanced photosynthetic function by displaying a hormetic response of electron transport rate (ETR), due to an increased fraction of open reaction centers, it is suggested to be activated by the low increase of reactive oxygen species (ROS). A low increase of ROS is regarded to be beneficial by stimulating defense responses and also triggering a more oxidized redox state of quinone A (QA), corresponding in S. pennellii under 50% deficit irrigation, to the lowest stomatal opening, resulting in reduction of water loss. Solanum pennellii was the most tolerant to drought, as it was expected, and could manage to have an adequate photochemical function with almost 30% water regime of well-watered plants. With 50% deficit irrigation, cv. Μ82 and cv. Santorini did not show any difference in photochemical efficiency to control plants and are recommended to be cultivated under deficit irrigation as an effective strategy to enhance agricultural sustainability under a global climate change. We conclude that instead of the previously used Fv/Fm ratio, the redox state of QA, as it can be estimated by the chlorophyll fluorescence parameter 1 - qL, is a better indicator to evaluate photosynthetic efficiency and select drought tolerant cultivars under deficit irrigation.

show abstract

Concepts of photochemical damage of Photosystem II and the role of excessive excitation

Cited by 47 publications

References 137 publications

Melanisation in Boreal Lichens Is Accompanied by Variable Changes in Non-Photochemical Quenching

Melanisation in Boreal Lichens Is Accompanied by Variable Changes in Non-Photochemical Quenching

Leaf Age-Dependent Photosystem II Photochemistry and Oxidative Stress Responses to Drought Stress in Arabidopsis thaliana Are Modulated by Flavonoid Accumulation

Harnessing Chlorophyll Fluorescence for Phenotyping Analysis of Wild and Cultivated Tomato for High Photochemical Efficiency under Water Deficit for Climate Change Resilience

Contact Info

Product

Resources

About