Wastewater with high NH_4^+-N is difficult to treat by traditional methods.So in this paper,a wild strain of photosynthetic bacteria was used for high NH_4^+-N wastewater treatment together with biomass recovery.Isola...Wastewater with high NH_4^+-N is difficult to treat by traditional methods.So in this paper,a wild strain of photosynthetic bacteria was used for high NH_4^+-N wastewater treatment together with biomass recovery.Isolation,identification,and characterization of the microorganism were carried out.The strain was inoculated to the biological wastewater treatment unit.The impacts of important factors were examined,including temperature,dissolved oxygen,and light intensity.Results showed that photosynthetic bacteria could effectively treat high NH_4^+-N wastewater.For wastewater with NH_4^+-N of 2300 mg·L^(-1),COD/N=1.0,98.3%of COD was removed,and cell concentration increased by 43 times.The optimal conditions for the strain's cell growth and wastewater treatment were 30℃,dissolved oxygen of 0.5-1.5 mg·L^(-1) and a light intensity of 4000 lx.Photosynthetic bacteria could bear a lower C/N ratio than bacteria in a traditional wastewater treatment process,but the NH_4^+-N removal was only 20%-40%because small molecule carbon source was used prior to NH_4^+-N.Also,the use of photosynthetic bacteria in chicken manure wastewater containing NH4+-N about 7000 mg·L^(-1) proved that photosynthetic bacteria could remove NH_4^+-N in a real case,finally,83.2%of NH_4^+-N was removed and 66.3%of COD was removed.展开更多
To study the relationships between C4 enzyme activities and yield, C4 enzyme activities （phosphoenolpyruvate carboxylase （PEPCase）, NADP-malate dehydrogenase （NADP-MDH）, NADP-malic enzyme （NADP-ME）, and pyruvat...To study the relationships between C4 enzyme activities and yield, C4 enzyme activities （phosphoenolpyruvate carboxylase （PEPCase）, NADP-malate dehydrogenase （NADP-MDH）, NADP-malic enzyme （NADP-ME）, and pyruvate phosphate dikinase （PPDK）） in different organs of ten soybean cultivars with different yields were measured at different growth stages in China. The result showed that four enzyme activities in C4 pathway were obviously different among cultivars, especially PPDK activity was not detected in the leaves of Dongnong 1567 and Dongnong 1068 and the young leaves of Gongjiao 9107-1 and Dongnong 97-172, but there were weak activities in pod coats. The order of C4 enzyme activities is young leaves 〈 old leaves 〈 pod coats. The correlation coefficients between PEPCase activity and yield and between NADP-MDH activity at blooming stage and yield were 0.6979 and 0.6565, respectively, and both reached the significant level （5%）, and PEPCase activity kept significant positive correlation with plant photosynthetic rate. There was a negative correlation between NADP-ME activity and yield, and no correlation was found between PPDK activity and yield.展开更多
Currently, single-cell C4 photosynthesis has been reported in four terrestrial plant species, Bienertia cycloptera, B. sinuspersici, B. kavirense and Suaeda aralocaspica, of family Chenopodiaceae. These species posses...Currently, single-cell C4 photosynthesis has been reported in four terrestrial plant species, Bienertia cycloptera, B. sinuspersici, B. kavirense and Suaeda aralocaspica, of family Chenopodiaceae. These species possess novel mechanisms of C4 photosynthesis through spatial partitioning of organelles and key enzymes in distinct cytoplasmic domains within single chlorenchyma cells. Anatomical and biochemical studies have shown that the three Bienertia species and S. aralocaspica utilize biochemical and organellar compartmentation to achieve the equivalent spatial separation of Kranz anatomy but within a single photosynthetic cell. These discoveries have challenged the paradigm for C4 photosynthesis in terrestrial plants which had suggested for more than 40 years that the Kranz feature was indispensably required for its C4 function. In this review, we focus on the recent progress in understanding the cellular and molecular mechanisms that control the spatial relationship of organelles in these unique single-cell C4 systems. The demonstrated interaction of dimorphic chloroplasts with microtubules and actin filaments has shed light on the importance of these cytoskeleton components in the intracellular partitioning of organelles. Future perspectives on the potential function of the cytoskeleton in targeting gene products to specific subcellular compartments are discussed.展开更多
The ubiquitin system is crucial for the development and fitness of higher plants.De-etiolation, during which green plants initiate photomorphogenesis and establish autotrophy, is a dramatic and complicated process tha...The ubiquitin system is crucial for the development and fitness of higher plants.De-etiolation, during which green plants initiate photomorphogenesis and establish autotrophy, is a dramatic and complicated process that is tightly regulated by a massive number of ubiquitylation/de-ubiquitylation events. Here we present site-specific quantitative proteomic data for the ubiquitylomes of de-etiolating seedling leaves of Zea mays L.(exposed to light for 1, 6, or 12 h)achieved through immunoprecipitation-based high-resolution mass spectrometry(MS). Through the integrated analysis of multiple ubiquitylomes, we identified and quantified 1926 unique ubiquitylation sites corresponding to 1053 proteins. We analyzed these sites and found five potential ubiquitylation motifs, KA, AXK, KXG, AK, and TK. Time-course studies revealed that the ubiquitylation levels of 214 sites corresponding to 173 proteins were highly correlated across two replicate MS experiments, and significant alterations in the ubiquitylation levels of 78 sites(fold change >1.5) were detected after de-etiolation for 12 h. The majority of the ubiquitylated sites we identified corresponded to substrates involved in protein and DNA metabolism, such as ribosomes and histones.Meanwhile, multiple ubiquitylation sites were detected in proteins whose functions reflect the major physiological changes that occur during plant de-etiolation, such as hormone synthesis/signaling proteins, key C4 photosynthetic enzymes, and light signaling proteins. This study on the ubiquitylome of the maize seedling leaf is the first attempt ever to study the ubiquitylome of a C4 plant and provides the proteomic basis for elucidating the role of ubiquitylation during plant de-etiolation.展开更多
基金Supported by the National Natural Science Foundation of China(51278489)
文摘Wastewater with high NH_4^+-N is difficult to treat by traditional methods.So in this paper,a wild strain of photosynthetic bacteria was used for high NH_4^+-N wastewater treatment together with biomass recovery.Isolation,identification,and characterization of the microorganism were carried out.The strain was inoculated to the biological wastewater treatment unit.The impacts of important factors were examined,including temperature,dissolved oxygen,and light intensity.Results showed that photosynthetic bacteria could effectively treat high NH_4^+-N wastewater.For wastewater with NH_4^+-N of 2300 mg·L^(-1),COD/N=1.0,98.3%of COD was removed,and cell concentration increased by 43 times.The optimal conditions for the strain's cell growth and wastewater treatment were 30℃,dissolved oxygen of 0.5-1.5 mg·L^(-1) and a light intensity of 4000 lx.Photosynthetic bacteria could bear a lower C/N ratio than bacteria in a traditional wastewater treatment process,but the NH_4^+-N removal was only 20%-40%because small molecule carbon source was used prior to NH_4^+-N.Also,the use of photosynthetic bacteria in chicken manure wastewater containing NH4+-N about 7000 mg·L^(-1) proved that photosynthetic bacteria could remove NH_4^+-N in a real case,finally,83.2%of NH_4^+-N was removed and 66.3%of COD was removed.
基金supported by the National Natural Science Foundation of China (30471092)the Genetically Modified Organisms Breeding Major Projects, China (2009ZX08009-089B)
文摘To study the relationships between C4 enzyme activities and yield, C4 enzyme activities （phosphoenolpyruvate carboxylase （PEPCase）, NADP-malate dehydrogenase （NADP-MDH）, NADP-malic enzyme （NADP-ME）, and pyruvate phosphate dikinase （PPDK）） in different organs of ten soybean cultivars with different yields were measured at different growth stages in China. The result showed that four enzyme activities in C4 pathway were obviously different among cultivars, especially PPDK activity was not detected in the leaves of Dongnong 1567 and Dongnong 1068 and the young leaves of Gongjiao 9107-1 and Dongnong 97-172, but there were weak activities in pod coats. The order of C4 enzyme activities is young leaves 〈 old leaves 〈 pod coats. The correlation coefficients between PEPCase activity and yield and between NADP-MDH activity at blooming stage and yield were 0.6979 and 0.6565, respectively, and both reached the significant level （5%）, and PEPCase activity kept significant positive correlation with plant photosynthetic rate. There was a negative correlation between NADP-ME activity and yield, and no correlation was found between PPDK activity and yield.
文摘Currently, single-cell C4 photosynthesis has been reported in four terrestrial plant species, Bienertia cycloptera, B. sinuspersici, B. kavirense and Suaeda aralocaspica, of family Chenopodiaceae. These species possess novel mechanisms of C4 photosynthesis through spatial partitioning of organelles and key enzymes in distinct cytoplasmic domains within single chlorenchyma cells. Anatomical and biochemical studies have shown that the three Bienertia species and S. aralocaspica utilize biochemical and organellar compartmentation to achieve the equivalent spatial separation of Kranz anatomy but within a single photosynthetic cell. These discoveries have challenged the paradigm for C4 photosynthesis in terrestrial plants which had suggested for more than 40 years that the Kranz feature was indispensably required for its C4 function. In this review, we focus on the recent progress in understanding the cellular and molecular mechanisms that control the spatial relationship of organelles in these unique single-cell C4 systems. The demonstrated interaction of dimorphic chloroplasts with microtubules and actin filaments has shed light on the importance of these cytoskeleton components in the intracellular partitioning of organelles. Future perspectives on the potential function of the cytoskeleton in targeting gene products to specific subcellular compartments are discussed.
基金supported by the National Key R&D Program of China(Grant No.2016YFD0101003)the “Strategic Priority Research Program” of the Chinese Academy of Sciences(Grant No.XDA08010206)the Agricultural Science and Technology Innovation Program of Jilin Province “Discovery of excellent germplasms and cultivation of inbred lines suitable for mechanized harvesting in maize”(Grant No.CXGC2017JQ019).
文摘The ubiquitin system is crucial for the development and fitness of higher plants.De-etiolation, during which green plants initiate photomorphogenesis and establish autotrophy, is a dramatic and complicated process that is tightly regulated by a massive number of ubiquitylation/de-ubiquitylation events. Here we present site-specific quantitative proteomic data for the ubiquitylomes of de-etiolating seedling leaves of Zea mays L.(exposed to light for 1, 6, or 12 h)achieved through immunoprecipitation-based high-resolution mass spectrometry(MS). Through the integrated analysis of multiple ubiquitylomes, we identified and quantified 1926 unique ubiquitylation sites corresponding to 1053 proteins. We analyzed these sites and found five potential ubiquitylation motifs, KA, AXK, KXG, AK, and TK. Time-course studies revealed that the ubiquitylation levels of 214 sites corresponding to 173 proteins were highly correlated across two replicate MS experiments, and significant alterations in the ubiquitylation levels of 78 sites(fold change >1.5) were detected after de-etiolation for 12 h. The majority of the ubiquitylated sites we identified corresponded to substrates involved in protein and DNA metabolism, such as ribosomes and histones.Meanwhile, multiple ubiquitylation sites were detected in proteins whose functions reflect the major physiological changes that occur during plant de-etiolation, such as hormone synthesis/signaling proteins, key C4 photosynthetic enzymes, and light signaling proteins. This study on the ubiquitylome of the maize seedling leaf is the first attempt ever to study the ubiquitylome of a C4 plant and provides the proteomic basis for elucidating the role of ubiquitylation during plant de-etiolation.
