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232. Proteomic study reveals photosynthesis as downstream of both MAP kinase and cAMP signaling pathways in Chlamydomonas reinhardtii
- Creator:
- Lee, C., Rhee, J.-K., Kim, D. G., and Choi, Y.-E.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, gene regulation, mass spectrometry, two-dimensional gel electrophoresis, 2, and 581
- Language:
- Multiple languages
- Description:
- Previously, our data indicated that both cAMP and MAP kinase signaling play important roles in microalgal physiology as well as in lipid or carotenoid biosynthesis. In order to understand downstream genes of these signaling pathways, we employed proteomics approach. Both signal pathways were first altered with specific signaling inhibitors or modulators. Treatment of specific inhibitors changed microalgal size and increased lipid contents. With the microalgal cells after treatments of specific signaling inhibitor or modulators, we performed the proteomics analysis to identify downstream genes responsible for these phenotypes. Interestingly, multiple photosynthesis genes were identified, particularly proteins associated with PSII. Our data suggested that MAP kinase and cAMP signaling affect the photosynthesis, thereby leading to microalgal lipid or carotenoid biosynthesis., C. Lee, J.-K. Rhee, D. G. Kim, Y.-E. Choi., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
233. Proton concentration in the thylakoid membranes can regulate energy distribution between the two photosystems
- Creator:
- Tongra, T., Bharti, S., and Jajoo, A.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, špenát, photosynthesis, light-harvesting complex, luminal pH, nonphotochemical quenching, oxygen consumption, oxygen evolution, spinach, 2, and 581
- Language:
- Multiple languages
- Description:
- The aim of our study was to investigate the role of protons in regulating energy distribution between the two photosystems in the thylakoid membranes. Low pH-induced changes were monitored in the presence of a proton blocker, N,N′-dicyclohexylcarbodiimide (DCCD). When thylakoid membranes were suspended in a low-pH reaction mixture and incubated with DCCD, then a decrease in the fluorescence intensity of photosystem II (PSII) was observed, while no change in the intensity of photosystem I (PSI) fluorescence occurred according to the measured fluorescence emission spectra at 77 K. Since low pH induced distribution of energy from PSII to PSI was inhibited in the presence of DCCD, we concluded that pH/proton concentration of the thylakoid membranes plays an important role in regulating the distribution of the absorbed excitation energy between both photosystems., T. Tongra, S. Bharti, A. Jajoo., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
234. PsbP-induced protein conformational changes around Cl- ions in the water oxidizing center of photosystem II
- Creator:
- Kondo, J. and Noguchi, T.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, Mn4CaO5 cluster, oxygen evolution, 2, and 581
- Language:
- Multiple languages
- Description:
- PsbP is an extrinsic protein of PSII having a function of Ca2+ and Cl- retention in the water-oxidizing center (WOC). In order to understand the mechanism how PsbP regulates the Cl- binding in WOC, we examined the effect of PsbP depletion on the protein structures around the Cl- sites using Fourier transform infrared (FTIR) spectroscopy. Light-induced FTIR difference spectra upon the S1-S2 transition were obtained using Cl--bound and NO3--substituted PSII membranes in the presence and absence of PsbP. A clear difference in the amide I band changes by PsbP depletion was observed between Cl--bound and NO3--substituted PSII samples, indicating that PsbP binding perturbed the protein conformations around the Cl-ion(s) in WOC. It is suggested that PsbP stabilizes the Cl- binding by regulating the dissociation constant of Cl- and/or an energy barrier of Cl- dissociation through protein conformational changes around the Cl- ion(s)., J. Kondo, T. Noguchi., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
235. Quality of supplementary LED lighting effects on growth and photosynthesis of two different Lactuca recombinant inbred lines (RILs) grown in a tropical greenhouse
- Creator:
- Choong, T. W., He, J., Qin, L., and Lee, S. K.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- pigmenty, světelné diody, fotosyntéza, pigments, light emitting diodes, photosynthesis, electron transport rate, leaf expansion, light- and CO2-saturated net photosynthetic rate, photochemical and nonphotochemical quenching, stomatal density, 2, and 581
- Language:
- Multiple languages
- Description:
- LED lamps with various combinations of red (R) and blue (B) wavelengths were used to supplement sunlight for the growth of a heat-resistant (HR) and heat-sensitive (HS) recombinant inbred lines (RIL) of lettuce. The RB-LED ratios were 100R:0B (0B), 92R:8B (8B), 84R:16B (16B), and 76R:24B (24B) with an equal PPFD of 100 μmol m-2 s-1. The greatest leaf expansion rates were observed at 8B for both genotypes. All HR-RILs had similar values of growth parameters and specific leaf area (SLA). However, higher values of growth parameters were observed in HS-RIL with 0B, 8B, and 16B than that under 24B and sunlight. Furthermore, HS-RIL had higher SLA under 0B compared to other conditions. Photosynthetic light-use efficiency and maximal oxygen evolution rate were the lowest under 8B for both genotypes. The quality of LED lighting, if provided, seemed to implicate genotype dependence, probably as a result of their different sensitivities to heat stress., T. W. Choong, J. He, L. Qin, S. K. Lee., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
236. Reduction of photosynthetic apparatus plays a key role in survival of the microalga Haematococcus pluvialis (Chlorophyceae) at freezing temperatures
- Creator:
- Chekanov, K., Vasilieva, S., Solovchenko, A., and Lobakova, E.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, cold stress, Haematococcys pluvialis, stress tolerance, 2, and 581
- Language:
- Multiple languages
- Description:
- The microalga Haematococcus pluvialis is a biotechnologically important microorganism producing a ketocarotenoid astaxanthin. Haematococcus exists either as metabolically active vegetative cells with a high chlorophyll content or astaxanthin-rich haematocysts (aplanospores). This microalga featuring outstanding tolerance to a wide range of adverse conditions is a highly suitable model for studies of freezing tolerance in phototrophs. The retention of H. pluvialis cell viability after freezing-thawing is ascribed to elevated antioxidant enzyme activity and high ketocarotenoid content. However, we report that only haematocysts characterized by a lower photosynthetic activity were resistant to freezing-thawing even without cryoprotectant addition. The key factors of haematocyst freezing tolerance were assumed to be a low water content, rigid cell walls, reduction of the membranous structures, photosynthesis downregulation, and low chlorophyll content. Collectively, viability of Haematoccus after freezing-thawing can be improved by forcing the transition of vegetative cells to freeze-tolerant haematocysts before freezing., K. Chekanov, S. Vasilieva, A. Solovchenko, E. Lobakova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
237. Regulating photoprotection improves photosynthetic growth and biomass production in QC-site mutant cells of the cyanobacterium Synechocystis sp. PCC 6803
- Creator:
- Huang, J.-Y., Hung, N.-T., Lin, K.-M., Chiu, Y.-F., and Chu, H.-A.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- cytochromy, fotosyntéza, ochrana před ultrafialovým zářením, cytochromes, photosynthesis, photoprotection, cytochrome b559, photosystem II, 2, and 581
- Language:
- Multiple languages
- Description:
- We characterized the photosynthetic growth of wild-type (WT) and QC-site mutant cells of the cyanobacterium Synechocystis sp. PCC 6803 grown in a photobioreactor under medium-intensity [~70 μmol(photon) m-2 s-1] and high-intensity [~200 μmol(photon) m-2 s-1] light conditions. Photosynthetic growth rate (the exponential phase) increased about 1.1-1.2 fold for the A16FJ, S28Aβ, and V32Fβ mutant compared with WT cells under medium-intensity light and about 1.2-1.3 fold under high-intensity light. Biomass production increased about 17-20% for A16FJ and S28Aβ mutant cells as compared with WT cells under medium-intensity light and about 14-17% for A16FJ and V32Fβ mutant cells under high-intensity light. The greater photosynthetic growth rate and biomass production of these QC-site mutant cells could be attributed to the increased photosynthesis efficiency and decreased dissipation of wasteful energy from phycobilisomes in mutants vs. WT cells. Our results support that manipulation of photoprotection may improve photosynthesis and biomass production of photosynthetic organisms., J.-Y. Huang, N.-T. Hung, K.-M. Lin, Y.-F. Chiu, H.-A. Chu., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
238. Relationship between flavonoids and photoprotection in shade-developed Erigeron breviscapus transferred to sunlight
- Creator:
- Zhou, R., Su, W. H., Zhang, G. F., Zhang, Y. N., and Guo, X. R.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, chlorophyll fluorescence, flavonoid, phenolics, protection, photodamage, 2, and 581
- Language:
- Multiple languages
- Description:
- Flavonoids are thought to participate in protection of the photosynthetic apparatus against photoinhibition under excessive light. Flavone glycoside, scutellarin, is a main active ingredient extracted from Erigeron breviscapus, the plant used in Chinese medicine. Shade-developed leaves of E. breviscapus were transferred from shade to full sunlight to quantify a relationship between the concentration of leaf scutellarin and tolerance to high radiation stress or the recovery from photoinhibition. The maximal quantum yield of PSII photochemistry showed a diurnal fluctuation in both shaded and sunlit leaves throughout the day. It indicated dynamic photoinhibition in the leaves of Erigeron, i.e., higher photoinhibition at solar noon and lower one in the morning and late afternoon. The sun-developed leaves reached the higher scutellarin content and values of nonphotochemical quenching coefficient with a lower degree of photoinhibition than the shade-developed leaves. When the shade-developed leaves were transferred to full sunlight, the content of scutellarin was declining continuously for 10 d and then was increasing for 15 d. After 50 d, all leaves became the sun-developed leaves with their scutellarin contents of about 138.5 ± 5.2 mg g-1(dry mass, DM) which was significantly higher than that of the shade-developed leaves [107.8 ± 9.8 mg g-1(DM)]. During acclimatization, the degree of photoinhibition was negatively correlated with the scutellarin content. Our results demonstrated a synchronous fluctuation between the flavonoid content and degree of protection against photoinhibition., R. Zhou, W. H. Su, G. F. Zhang, Y. N. Zhang, X. R. Guo., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
239. Relationship between photosynthetic rate, water use and leaf structure in desert annual and perennial forbs differing in their growth
- Creator:
- Gonzalez-Paleo, L. and Ravetta, D. A.
- Format:
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- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, leaf anatomy, Physaria, relative growth rate, specific leaf area, total biomass, xylem anatomy, 2, and 581
- Language:
- Multiple languages
- Description:
- Specific leaf area (SLA) is a key trait to screen plants for ecological performance and productivity; however, the relationship between SLA and photosynthesis is not always up-scalable to growth when comparing multiple species with different life cycles. We explored leaf anatomy in annual and perennial species of Physaria, and related it to photosynthesis and water loss. The annual Physaria gracilis had higher SLA, thinner leaves, and lower investment in protective tissues, than perennial P. mendocina. Physaria angustifolia (annual), and P. pinetorum (perennial) showed intermediate values. Both perennials had a thicker palisade and high photosynthesis, relative to annuals. The larger leaf veins of perennials should allow high water availability to the mesophyll. The thicker palisade should determine high resistance to water flow and help explain their high water-use efficiency. These leaf functions reflect the construction of long-lived leaves that efficiently use resources under environmental limitations of arid environments., L. Gonzalez-Paleo, D. A. Ravetta., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
240. Relationship between root vigour, photosynthesis and biomass in soybean cultivars during 87 years of genetic improvement in the northern China
- Creator:
- Cui, X., Dong, Y., Gi, P., Wang, H., Xu, K., and Zhang, Z.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, breeding, gas exchange, Glycine max, root biomass, 2, and 581
- Language:
- Multiple languages
- Description:
- During the last century, the world soybean yield has been constantly enhancing at a remarkable rate. Factors limiting the soybean yield may be multiple. It is widely acknowledged that changes of root metabolism can influence aboveground characteristics, such as the seed yield and photosynthesis. In this study, we considered root bleeding sap mass (BSM) and root activity (RA) as indicators of the root growth vigour. We used 27 soybean cultivars, spanning from 1923 to 2009, to evaluate the contribution of root characteristic improvement to efficient photosynthesis and dry matter production. The BSM, RA, net photosynthetic rate (P N), and organ biomass were measured at different growth stages, such as the fourth leaf node, flowering, podding, and seed-filling stage. Our results showed that the soybean cultivars increased their biomass and P N thanks to genetic improvement. At the same time, BSM and RA also increased in dependence on a year of cultivar release. However, both P N and biomass were positively correlated with root characteristics only at the podding stage. Our data revealed that the improved root characteristic may have contributed to the enhanced photosynthesis, biomass, and yield of soybean cultivars during last 87 years of genetic improvement. We suggest that BSM and RA could be used as important indexes for further practice in soybean production improvement., X. Cui, Y. Dong, P. Gi, H. Wang, K. Xu, Z. Zhang., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public