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1132. 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
1133. Regulation of the ubiquitin proteasome system in mechanically injured human skeletal muscle
- Creator:
- Seifert, M., Gosenca, D., Ponelies, N., Ising, N., Patel, M. B., Obertacke, U., and Majetschak, M.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, biochemie, katabolismus, biochemistry, catabolism, svalová kachexie, epoxomicin, muscle cachexia, ubiquitin-protein ligase complexes, epoxomixin, adamantane-acetyl-(6-aminohexanoyl)3-(leucinyl)3-vinyl(methyl)-sulfone, 2, and 577
- Language:
- English
- Description:
- Metabolic consequences of direct muscle trauma are insufficiently defined. Their effects on the ubiquitin-proteasome pathway (UPP) of protein degradation in human skeletal muscles are as yet unknown. Thus, we investigated whether the UPP is involved in the metabolic response evoked in directly traumatized human skeletal muscles. Biopsies were obtained from contused muscles after fractures and from normal muscles during elective implant removal (control). As estimated by western blot analyses, concentrations of free ubiquitin and ubiquitin protein conjugates were similar in extracts from injured and uninjured muscles. Ubiquitin protein ligation rates were reduced after injury (1.5±0.2 vs. 1.0±0.15 fkat/μg; p=0.04). Chymotryptic-, tryptic- and caspase-like proteasome peptidase activities (total activity minus activity in the presence of proteasome inhibitors) increased significantly after trauma (p=0.04 - 0.001). Significant increases in total chymotryptic- and caspase-like activities were attributable to proteasome activation. Our results extend the possible role of the UPP in muscle wasting to direct muscle trauma. They further suggest that the effects of direct mechanical trauma are not limited to the proteasome and imply that ubiquitin protein ligase systems are also involved. Based on the potential role of the UPP in systemic diseases, it might also be a therapeutic target to influence muscle loss in critically ill blunt trauma patients, in which large proportions of muscle are exposed to direct trauma. and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1134. Řekni mi, kde rosteš, já ti povím, jaká jsi
- Creator:
- Koukol, Ondřej
- Format:
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Botanika, mykologie, lichenologie, molekulární biologie, virologie, genetika, životní prostředí, ekologie, mycology, lichenology, molecular biology, virology, environment, ecology, genetics, 2, and 58
- Language:
- Czech
- Description:
- Naše znalosti o ekologii a rozšíření řady druhů hub byly po dlouhou dobu založeny pouze na pozorování plodnic a sporulujících útvarů v terénu a na identifikaci izolovaných druhů hub. Nedávné pokroky a dostupnost metod založených na studiu DNA a jejich téměř rutinní používání v laboratořích rozšířilo naše znalosti o substrátech kolonizovaných různými druhy hub. Na druhou stranu se ukázalo, že některé druhy kolonizují stejný substrát, ale na geograficky velmi vzdálených lokalitách. Některé druhy ani nelze zařadit do jasně vymezené ekologické skupiny, mění svou ekologii v průběhu svého životního cyklu., Our information about the ecology and distribution of particular fungal species has for a long time been based only on observations of fruit bodies and sporulating structures in the field and on identification of isolated fungal strains. Recent developments in molecular methods and their routine use in mycology have revealed that some fungi may colonize different substrates than originally supposed. On the other hand, other fungi colonize their typical habitats in localities that are enormously distant from each other. Some fungi may not be easily assigned to a single ecological group, as they change various life styles during their life cycle., and Ondřej Koukol.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1135. Relationship between antioxidant potential and oxidative damage to lipids, proteins and DNA in aged rats
- Creator:
- Monika Sivoňová, Tatarková, Z., Zdeňka Ďuračková, Dušan Dobrota, Ján Lehotský, Matáková, T., and Peter Kaplán
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, fyziologie živočichů, stárnutí, antioxidanty, peroxidázy, animal physiology, aging, antioxidants, peroxidases, comet assay, total sulfhydryl groups, 2, and 577
- Language:
- English
- Description:
- Oxidative stress has been implicated to play a major role in aging and age-related diseases. In the present study, we investigated the effects of aging on the total antioxidant capacity, uric acid, lipid peroxidation, total sulfhydryl group content and damage to DNA in adult (6 months), old (15 months) and senescent (26 months) male Wistar rats. The antioxidant capacity, determined by phycoerythrin-based TRAP method (total peroxyl radical-trapping potential) was significantly decreased in the plasma and myocardium of old and senescent rats, whereas plasma level of uric acid was elevated in 26-month-old rats. Age-related decline in plasma and heart antioxidant capacity was accompanied by a significant loss in total sulfhydryl group content, increased lipid peroxidation and higher DNA damage in lymphocytes. Correlations between TRAP and oxidative damage to lipids, proteins and DNA suggest that the decline in antioxidant status may play an important role in age-related accumulation of cell damage caused by reactive oxygen species., M. Sivoňová, Z. Tatarková, Z. Ďuračková, D. Dobrota, J. Lehotský, T. Matáková, P. Kaplán., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1136. 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
1137. Relationship between photosynthetic pigments and chlorophyll fluorescence in soybean under varying phosphorus nutrition at ambient and elevated CO2
- Creator:
- Singh, S. K., Reddy, V. R., Fleisher, D. H., and Timlin, D. J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- podíl chlorofyl/karotenoidy, fotochemické zhášení, vztahy, reakční křivky, chlorophyll/carotenoids ratio, energy dissipation, photochemical quenching, relationships, response curves, 2, and 581
- Language:
- Multiple languages
- Description:
- To assess the relationship between chlorophyll (Chl) fluorescence (CF) and photosynthetic pigments, soybean was grown under varying phosphorus (P) nutrition at ambient and elevated CO2 (EC). The EC stimulated, but P deficiency decreased plant height, node numbers, and leaf area concomitantly with the rates of stem elongation, node addition, and leaf area expansion. Under P deficiency, CF parameters and pigments declined except that carotenoids (Car) were relatively stable indicating its role in photoprotection. The CF parameters were strongly related with Chl concentration but not with Chl a/b or Car. However, total Chl/Car showed the strongest association with CF parameters such as quantum efficiency and yield of photosystem II. This relationship was not affected by CO2 treatment. The high correlation between CF and total Chl/Car underscores the significance of the quantification of both, Chl and Car concentrations, to understand the photochemistry and underlying processes of photoprotection and mechanisms of excess energy dissipation in a given environment., S. K. Singh, V. R. Reddy, D. H. Fleisher, D. J. Timlin., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1138. 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:
- print, bez média, and svazek
- 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
1139. 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
1140. Relationship of photosynthetic efficiency and seed-setting rate in two contrasting rice cultivars under chilling stress
- Creator:
- Wang, L.-Z., Wang, L.-M., Xiang, H.-T., Luo, Y., Li, R., Li, Z.-J., Wang, C.-Y., and Meng, Y.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- peroxidázy, chlorofyl, peroxidases, chlorophyll, kyselina abscisová, fluorescence chlorofylu, malondialdehyde, prolin, superoxid dismutáza, antioxidační enzymy, abscisic acid, chlorophyll fluorescence, proline, superoxide dismutase, antioxidative enzymes, 2, and 581
- Language:
- Multiple languages
- Description:
- Low temperature during the vegetative stage affects rice (Oryza sativa L.) seed-setting rate in Heilongjiang province at Northeast China. However, little is known about changes of the photosynthetic rate and physiological response in contrasting rice cultivars during chilling periods. In this study, two rice cultivars with different chilling tolerance were treated with 15°C from June 27 to July 7. The chilling-susceptive cultivar, Longjing11 (LJ11), showed a significant decrease in a ripening rate and seed-setting rate after being treated for four days, whilst chilling-tolerant cultivar, Kongyu131 (KY131), was only slightly affected after 4-d treatment. The photosynthetic activities, chlorophyll contents, and antioxidative enzyme activities in LJ11 decreased significantly along with the chilling treatment. The decrease in ß-carotene contents might play a role as it could cause direct photooxidation of chlorophylls and lead to the inhibition of the photosynthetic apparatus. In the meantime, no significant damage was found in leaves of KY131 from June 27 to July 11. In conclusion, the chilling-tolerance mechanism of rice is tightly related to the photosynthetic rate, metabolism of reactive oxygen species, and scavenging system in the vegetative stage., L.-Z. Wang, L.-M. Wang, H.-T. Xiang, Y. Luo, R. Li, Z.-J. Li, C.-Y. Wang, Y. Meng., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public