Photoinhibition — a historical perspective

Adir, Noam; Zer, Hagit; Shochat, Susana Geifman; Ohad, Itzhak

doi:10.1007/1-4020-3324-9_84

Cited by 121 publications

(189 citation statements)

References 201 publications

Supporting

Mentioning

179

Contrasting

Unclassified

Order By: Relevance

“…C-550) proteins, and is likely important for complex assembly (Suorsa et al, 2004). Thus, potential v-D1 proteins represent a unique form of this critical photosynthetic reaction center protein, which may effect the stability and/or assembly of PSII (for a detailed review, see Adir et al, 2003 andMattoo, 2006). v-D1 sequences in the global ocean sampling expedition project We tested the generality of the novel v-D1 proteins from this initial environmental Mediterranean and Red Seas data set by exploring the GOS expedition shotgun sequencing project Yooseph et al, 2007), which also includes within the Sargasso metagenome (Venter et al, 2004).…”

Section: Resultsmentioning

confidence: 99%

Viral photosynthetic reaction center genes and transcripts in the marine environment

et al. 2007

Self Cite

View full text Add to dashboard Cite

Cyanobacteria of the genera Synechococcus and Prochlorococcus are important contributors to photosynthetic productivity in the open ocean. The discovery of genes (psbA, psbD) that encode key photosystem II proteins (D1, D2) in the genomes of phages that infect these cyanobacteria suggests new paradigms for the regulation, function and evolution of photosynthesis in the vast pelagic ecosystem. Reports on the prevalence and expression of phage photosynthesis genes, and evolutionary data showing a potential recombination of phage and host genes, suggest a model in which phage photosynthesis genes help support photosynthetic activity in their hosts during the infection process. Here, using metagenomic data in natural ocean samples, we show that about 60% of the psbA genes in surface water along the global ocean sampling transect are of phage origin, and that the phage genes are undergoing an independent selection for distinct D1 proteins. Furthermore, we show that different viral psbA genes are expressed in the environment.

show abstract

Section: Resultsmentioning

confidence: 99%

Viral photosynthetic reaction center genes and transcripts in the marine environment

et al. 2007

Self Cite

View full text Add to dashboard Cite

show abstract

“…This occurs especially under stress conditions such as exposure of the cells to HL intensities or drought (Hideg et al, 2001(Hideg et al, , 2002Trebst et al, 2002). In these conditions, the PQ pool may become highly reduced, and the lightinduced loss of PSII activity occurs (for review, see Adir et al, 2003). 1 O 2 is a very reactive oxygen species that can attack proteins, pigments, nucleic acids, and lipids, and is thought to be the most harmful ROS responsible for light-induced loss of PSII activity (Vass et al, 1992), degradation of the D1 protein (one of the PSII reaction center proteins), and pigment bleaching (for review, see Prasil et al, 1992;Aro et al, 1993;Nixon et al, 2005;Vass and Aro, 2007;Tyystjärvi, 2008).…”

Section: Resistance Of the Flv4-2/oe Mutant To Photodamage Correlatesmentioning

confidence: 99%

Flavodiiron Protein Flv2/Flv4-Related Photoprotective Mechanism Dissipates Excitation Pressure of PSII in Cooperation with Phycobilisomes in Cyanobacteria

et al. 2013

View full text Add to dashboard Cite

(A.R., I.V.) Oxygenic photosynthesis evolved with cyanobacteria, the ancestors of plant chloroplasts. The highly oxidizing chemistry of water splitting required concomitant evolution of efficient photoprotection mechanisms to safeguard the photosynthetic machinery. The role of flavodiiron proteins (FDPs), originally called A-type flavoproteins or Flvs, in this context has only recently been appreciated. Cyanobacterial FDPs constitute a specific protein group that evolved to protect oxygenic photosynthesis. There are four FDPs in Synechocystis sp. PCC 6803 (Flv1 to Flv4). Two of them, Flv2 and Flv4, are encoded by an operon together with a Sll0218 protein.Their expression, tightly regulated by CO 2 levels, is also influenced by changes in light intensity. Here we describe the overexpression of the flv4-2 operon in Synechocystis sp. PCC 6803 and demonstrate that it results in improved photochemistry of PSII. The flv4-2/OE mutant is more resistant to photoinhibition of PSII and exhibits a more oxidized state of the plastoquinone pool and reduced production of singlet oxygen compared with control strains. Results of biophysical measurements indicate that the flv4-2 operon functions in an alternative electron transfer pathway from PSII, and thus alleviates PSII excitation pressure by channeling up to 30% of PSII-originated electrons. Furthermore, intact phycobilisomes are required for stable expression of the flv4-2 operon genes and for the Flv2/Flv4 heterodimer-mediated electron transfer mechanism. The latter operates in photoprotection in a complementary way with the orange carotenoid protein-related nonphotochemical quenching. Expression of the flv4-2 operon and exchange of the D1 forms in PSII centers upon light stress, on the contrary, are mutually exclusive photoprotection strategies among cyanobacteria.Photosynthetic light reactions are evolutionarily highly conserved among oxygenic photosynthetic organisms from cyanobacteria to higher plants. Because of dangerous chemistry of the water splitting reactions, oxygenic photosynthesis produces reactive oxygen species (ROS) and other radicals that potentially could destroy the photosynthetic machinery. To avoid permanent damage, all oxygenic photosynthetic organisms are equipped with an array of various photoprotective and regulatory mechanisms. Accumulating evidence on these regulatory mechanisms has revealed vast evolutionary differences between organisms performing oxygenic photosynthesis.Photosynthetic organisms have a capacity to adjust to different light intensities and to changes in the availability of electron sinks, which depends largely on metabolic cues. When light or metabolic conditions change, photosystems can dissipate excess energy as heat in nonphotochemical energy dissipation processes in the light-harvesting antenna systems (for review, see Horton et al., 1996;Müller et al., 2001). Cyanobacteria have phycobilisomes (PBs) as light-harvesting antenna, which also participate in state transitions (for review, see van Thor et al., 1998;Mullineaux ...

show abstract

“…The ability of oxygenic photosynthetic organisms, such as cyanobacteria and green plants, to convert solar energy into chemical energy via photosynthesis is inhibited at high irradiances in a process termed photoinhibition (Aro et al, 1993;Adir et al, 2003). Such inhibition is considered to be a major factor in limiting crop yields, especially when plants are exposed to other types of abiotic stress (Murata et al, 2007;Takahashi and Badger, 2011).…”

Section: Introductionmentioning

confidence: 99%

“…At a molecular level, a major target for photodamage is the photosystem II (PSII) complex of the thylakoid membrane, which functions as the light-driven water: plastoquinone oxidoreductase of the photosynthetic electron transport chain (Wydrzynski and Satoh, 2005). Although PSII contains 20 subunits or more, depending on the species, the D1 reaction center polypeptide, which binds many of the cofactors involved in electron transfer through the complex, is most prone to irreversible oxidative damage in the light (Adir et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

“…To maintain PSII activity, irreversibly damaged subunits are replaced by newly synthesized copies in the so-called PSII repair cycle (Adir et al, 2003;Nixon et al, 2005Nixon et al, , 2010. This process involves partial disassembly of the damaged PSII complex, degradation and replacement of the damaged subunit by a newly synthesized copy, reattachment of disassembled, undamaged PSII subunits, and light-driven assembly of the Mn 4 Ca water-splitting catalyst (Nixon et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Subunit Organization of a Synechocystis Hetero-Oligomeric Thylakoid FtsH Complex Involved in Photosystem II Repair

Boehm

Krynická

et al. 2012

The Plant Cell

View full text Add to dashboard Cite

FtsH metalloproteases are key components of the photosystem II (PSII) repair cycle, which operates to maintain photosynthetic activity in the light. Despite their physiological importance, the structure and subunit composition of thylakoid FtsH complexes remain uncertain. Mutagenesis has previously revealed that the four FtsH homologs encoded by the cyanobacterium Synechocystis sp PCC 6803 are functionally different: FtsH1 and FtsH3 are required for cell viability, whereas FtsH2 and FtsH4 are dispensable. To gain insights into FtsH2, which is involved in selective D1 protein degradation during PSII repair, we used a strain of Synechocystis 6803 expressing a glutathione S-transferase (GST)-tagged derivative (FtsH2-GST) to isolate FtsH2-containing complexes. Biochemical analysis revealed that FtsH2-GST forms a hetero-oligomeric complex with FtsH3. FtsH2 also interacts with FtsH3 in the wild-type strain, and a mutant depleted in FtsH3, like ftsH2 2 mutants, displays impaired D1 degradation. FtsH3 also forms a separate heterocomplex with FtsH1, thus explaining why FtsH3 is more important than FtsH2 for cell viability. We investigated the structure of the isolated FtsH2-GST/FtsH3 complex using transmission electron microscopy and single-particle analysis. The three-dimensional structural model obtained at a resolution of 26 Å revealed that the complex is hexameric and consists of alternating FtsH2/FtsH3 subunits.

show abstract

Photoinhibition — a historical perspective

Cited by 121 publications

References 201 publications

Viral photosynthetic reaction center genes and transcripts in the marine environment

Viral photosynthetic reaction center genes and transcripts in the marine environment

Flavodiiron Protein Flv2/Flv4-Related Photoprotective Mechanism Dissipates Excitation Pressure of PSII in Cooperation with Phycobilisomes in Cyanobacteria

Subunit Organization of a Synechocystis Hetero-Oligomeric Thylakoid FtsH Complex Involved in Photosystem II Repair

Contact Info

Product

Resources

About