Cobalt induced changes in photosystem activity in Synechocystis PCC 6803: Alterations in energy distribution and stoichiometry

Tiwari, Swati; Mchanty, Prasanna

doi:10.1007/bf00033123

Cited by 16 publications

(6 citation statements)

References 43 publications

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“…These results suggest that low concentrations of Co 2+ stimulate electron transport at the donor side of PSII. Our results are in agreement with those reported by Tiwari and Mohanty (1996) who observed that Synechocystis cells grown in a medium containing 10 mmol.L -1 CoCl 2 showed a large stimulation (50 %) of O 2 evolution and an overall increase (~30 %) in the rate of photosynthetic electron transport resulting from a small increase (15-20 %) in the number of PSII units in Co 2+ -grown cells.…”

Section: Discussionsupporting

confidence: 94%

“…These results are in agreement with those of El-Naggar et al (1999) who found that low Co 2+ concentration increased both O 2 evolution and dark respiration in two cyanobacterial species, C. fusca and N. muscorum, whereas higher concentrations were inhibitory. Further confirmation of our results can be found in the data of Tiwari and Mohanty (1996) who reported that Synechocystis PCC 6803 cell growth in a medium containing 10 mmol.L -1 CoCl 2 exhibited a large stimulation (50 %) of O 2 evolution and an increase (~30 %) in photosynthetic electron transport. With regard to the observed inhibition as a result of the addition of higher concentrations of Co 2+ , ElSheekh and Hammouda (1992) reported that 25 and 50 mmol.L -1 Co 2+ inhibited O 2 evolution of Chlorella minutissima by 58.3 and 70.3 %, respectively.…”

Section: Discussionsupporting

confidence: 90%

“…Growth of Synechocystis PCC 6803 cells in 10 mmol.L -1 CoCl 2 stimulates the PSII electron transport rates (Tiwari and Mohanty, 1993). Tiwari and Mohanty (1996) suggested that supplementation of 10 mmol.L -1 CoCl 2 to the normal growth medium of Synechocystis PCC 6803 causes multiple changes involving a small increase in PSII to PSI ratio, enhanced funneling of energy to PSII and an increase in PSI electron transport, together with decreased PSI cross section and a reduction in the intersystem pool size. The cumulative effects of these alterations cause stimulation in electron transport and O 2 evolution.…”

Section: Introductionmentioning

confidence: 99%

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Effect of cobalt on growth, pigments and the photosynthetic electron transport in Monoraphidium minutum and Nitzchia perminuta

El‐Sheekh

El-Naggar

Osman

et al. 2003

Braz. J. Plant Physiol.

108

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The unicellular green alga Monoraphidium minutum and the diatom Nitzschia perminuta were cultured under different concentrations of Co 2+ . Growth and pigment content were slightly increased at low concentrations and inhibited by high Co 2+ concentrations. The results concerning the effect of different concentrations of Co 2+ on photosynthetic O 2 evolution showed a reduction in the amount of O 2 evolved by each alga in response to increasing Co 2+ concentrations. However, an increase in O 2 evolution for both M. minutum and N. perminuta was observed at relatively low Co 2+ concentrations. Photosynthetic electron transport in M. minutum was more sensitive to Co 2+ toxicity than in N. perminuta. On the other hand, the effect of the heavy metal on respiration showed that higher Co 2+ concentrations were inhibitory to O 2 uptake by the two algal species. Low Co 2+ concentrations stimulated O 2 uptake by M. minutum throughout the experimental period. However, in N. perminuta, different concentrations of Co 2+ led to a reduction of O 2 uptake. To localize the action site of Co 2+ in the photosynthetic electron transport chain, the fluorescence induction technique was carried out. According to the results obtained, the inhibitory action of Co 2+ is located on the acceptor side of PSII for both M. minutum and N. perminuta.

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Section: Discussionsupporting

confidence: 94%

Section: Discussionsupporting

confidence: 90%

Section: Introductionmentioning

confidence: 99%

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Effect of cobalt on growth, pigments and the photosynthetic electron transport in Monoraphidium minutum and Nitzchia perminuta

El‐Sheekh

El-Naggar

Osman

et al. 2003

Braz. J. Plant Physiol.

108

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“…At 750 nm the absorption of the cell suspension was adjusted to give approximately the same reading. Room temperature fluorescence emission spectra of the cells were recorded on a Perkin-Elmer LS-5 spectrofluorimeter following Tiwari and Mohanty (1996). PSII : PSI ratio analysis was done by spectrofluorimetry according to Gan et al (2014), and Amirlatifi et al (2018).…”

Section: Methodsmentioning

confidence: 99%

Влияние щелочности, сверхнизкой концентрации диоксида углерода и интенсивности излучения на спектральные свойства, фитобилисомы, фотосинтез, фотосистемы и функциональные группы нативной цианобактерии Calothrix sp. ISC 65

Abbasi¹,

Shokravi²,

Golsefidi³

et al. 2019

Algologia

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In this research, Calothrix sp. ISC 65 was characterized physiologically by the combination of extremely low irradiance (2 μEm -2 s -1 ), different alkalinity (pH 7, 9, 11), and extremely limited carbon dioxide concentration (no aeration, no carbon dioxide enrichment).Spectroscopical analysis showed that pH 9, after 96 hours, caused a significant increase in growth rate, chlorophyll, and phycocyanin production. A lower (pH of 7) caused a decrease of phycobilisome production even after 24 hours. Excitation of the light harvesting complex and the reaction center of photosystems resulted from a pH of 9. Phycocyanin seems to be the main part of phycobilisome but pH 9 caused phycoerythrin and allophycocyanin production excitation in the outer part of the photosynthetic antenna as well. A fluorimetric and photosynthesis-irradiance curve analysis showed that increasing alkalinity (up to pH 9) caused an increase in photosynthesis efficiency and a decrease of non-photochemical fluorescence especially after 96 hours. PSII : PSI ratio increased by increasing alkalinity from pH 7 to 9 and reached the highest level after 96 hours. Surface response plot analysis showed that there is a narrow border line around pH 9 and 96 hours which caused the highest PSII : PSI ratio. FTIR analysis showed that alkalinity caused configuration changes of the functional groups. The difference of the functional group patterns between pH 7 and 11 was significant especially after 24 hours. Differences in asymmetric carbon vibration, lipid stretching and OH bending of the polysaccharides occurred with both pH 9 and 11 treatments. pH 9 caused the most physiological activities in Calothrix sp. ISC 65 at extremely limited irradiance and carbon dioxide concentration. K e y w o r d s : alkalinity, Calothrix, cyanobacteria, dissolved inorganic carbon, limited irradiance A b b r e v i a t i o n s : APC  allophycocyanin, CCM  carbon dioxide concentrating mechanism, DIC  dissolved inorganic carbon, PBS  phycobilisome, PC  phycocyanin, PE  phycoerythrin, PSI, PSII  photosystems I and II

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“…[1] However, high concentrations of Co are inhibitory for growth, chlorophyll synthesis and induce changes in photosynthetic activity. [2][3][4] Toxicity symptoms due to excess Co are chlorosis, necrosis, and root tip damage in higher plants.…”

mentioning

confidence: 99%

Response to cobalt toxicity in lichen Pseudevernia furfuracea; uptake, photosynthetic quantum yield, membrane integrity and deoxyribonucleic acid fragmentation

Yiğittürk

Özakça

Çavuşoğlu³

et al. 2016

FNG & Bilim Tıp Dergisi

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Pseudevernia furfuracea'da kobalt toksisitesine yanıt; alım, fotosentetik kuantum verimi, membran bütünlüğü ve deoksiribonükleik asit fragmantasyonu ÖZ Amaç: Bu çalışmada fotosistem II fotosentetik kuantum verimi, membran bütünlüğü ve deoksiribonükleik asit (DNA) fragmantasyonu formasyonu üzerinde kobaltın (Co) toksik potansiyeli incelendi. Gereç ve yöntemler: Oligonükleozomal DNA fragmantasyonu terminal deoksinükleotidil transferaz dUTP çentik uç işaretleme (TUNEL) testi ile tespit edildi. Lipid peroksidasyonu malondialdehit analizi ile belirlendi. Bulgular: Bir, üç ve 24 saat boyunca farklı Co konsantrasyonlarına (NO3)2 (5, 15 ve 30 mM) maruziyetten sonra Pseudevernia furfuracea'da Fv/Fm oranı azaldı. Co 2+ -tedavisi likende Co birikimine yol açtı, hidrojen peroksit üretimi ciddi oksidatif stres başlattı, membran bütünlüğüne zarar verdi ve malondialdehit ile ölçüldüğü üzere lipid peroksidasyonu oluşturdu. On beş mM ve 30 mM Co (NO3)2 ile tedavi edilen örneklerin hücre ölümü yüzdesi 5 mM ile tedavi edilen gruptan daha yüksek idi. Sonuç: Bildiğimiz kadarıyla, bu çalışma Pseudevernia furfuracea'nın fikobiont katmanında in situ yüksek oranda DNA fragmantasyonu tespit ederken mikobiont katmanda daha düşük oranda TUNEL pozitif hücre olduğunu gösteren ilk çalışmadır. Kobalt maruziyetinin Pseudevernia furfuracea'da oksidatif stres ve DNA fragmantasyonunun eşlik ettiği bozulmuş fotosenteze yol açtığı sonucuna varıldı; tüm bu etkiler konsantrasyona bağımlı idi.Anahtar sözcükler: Kobalt; deoksiribonükleik asit fragmantasyonu; liken; oksidatif stres; Pseudevernia furfuracea; TUNEL. ABSTRACT Objectives:This study aims to examine the toxic potential of Cobalt (Co) on photosystem II photosynthetic quantum yield, membrane integrity, and deoxyribonucleic acid (DNA) fragmentation formation. Materials and methods: Oligonucleosomal DNA fragmentation was detected by terminal deoxynucleotidyl transferase-dUTP nick end labeling (TUNEL) assay. Lipid peroxidation was determined with malondialdehyde analyzing. Results: The Fv/Fm ratio decreased in Pseudevernia furfuracea following exposure to various concentrations of Co (NO3)2 (5, 15 and 30 mM) for one, three and 24 hours. Co 2+ -treatment caused the accumulation of Co in lichen, induced severe oxidative stress by the generation of hydrogen peroxide, impaired the membrane integrity, and induced lipid peroxidation as measured by malondialdehyde. Samples treated with 15 mM and 30 mM of Co (NO3)2 had higher percentage of cell death than 5 mM-treated group. Conclusion: To our knowledge, this is the first study detecting a high rate of DNA fragmentation in situ in phycobiont layer of Pseudevernia furfuracea; while it reveals that mycobiont layer has a lower rate of TUNEL-positive cells. It has been concluded that Co exposure results in impaired photosynthesis accompanied by oxidative stress and DNA fragmentation in Pseudevernia furfuracea; all these effects were concentration-dependent.

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Cobalt induced changes in photosystem activity in Synechocystis PCC 6803: Alterations in energy distribution and stoichiometry

Cited by 16 publications

References 43 publications

Effect of cobalt on growth, pigments and the photosynthetic electron transport in Monoraphidium minutum and Nitzchia perminuta

Effect of cobalt on growth, pigments and the photosynthetic electron transport in Monoraphidium minutum and Nitzchia perminuta

Response to cobalt toxicity in lichen Pseudevernia furfuracea; uptake, photosynthetic quantum yield, membrane integrity and deoxyribonucleic acid fragmentation

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