Elevated CO2 concentrations were found to cause early senescence during leaf development in sunflower (Helianthus annuus L.) plants, probably by reducing nitrogen availability since key enzymes of nitrogen metabolism, including nitrate reductase (NR); glutamine synthetase (GS) and glutamate dehydrogenase (GDH), were affected. Elevated CO2 concentrations significantly decreased the activity of n...

Natural photosynthesis harnesses solar energy to convert CO2 and water to value-added chemical products for sustaining life. We present a hybrid bioinorganic approach to solar-to-chemical conversion in which sustainable electrical and/or solar input drives production of hydrogen from water splitting using biocompatible inorganic catalysts. The hydrogen is then used by living cells as a source o...

Ralstonia eutropha is a facultative chemolithoautotrophic bacterium that uses the Calvin-Benson-Bassham (CBB) cycle for CO2 fixation. This study showed that R. eutropha strain H16G incorporated (13)CO2, emitted by the oxidative decarboxylation of [1-(13)C1]-glucose, into key metabolites of the CBB cycle and finally into poly(3-hydroxybutyrate) [P(3HB)] with up to 5.6% (13)C abundance. The carbo...

Iron nutrient deficiency was investigated in leaves of hydroponically grown sugar beets (Beta vulgaris) to determine how ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) gene expression is affected when thylakoid components of photosynthesis are diminished. Rubisco polypeptide content was reduced by 60% in severely iron-stressed leaves, and the reduction was directly correlated to chlo...

Studies on autotrophic CO2 fixation by the filamentous anoxygenic photosynthetic bacterium Oscillochloris trichoides strain DG-6 demonstrated that, unlike other green bacteria, this organism metabolized CO2 via the reductive pentose phosphate cycle. Both key enzymes of this cycle--ribulose-1,5-bisphosphate carboxylase/oxygenase and phosphoribulokinase--were detected in cell extracts. The main p...

The authors have developed and validated a photosynthetic-sterility model for grain production monitoring under the background of climate change and Asian economic growth in developing countries. This paper presents an application of the model to evaluate car-bonfixation rates in yields of paddy rice, winter wheat, and maize in Asia. The validation of the model is based on carbon partition-ing ...

Using first principle methodologies, we investigate the subtle competition between σ H-bond and π stacking interaction between CO2 and imidazole either isolated, adsorbed on a gold cluster or adsorbed on a gold surface. These computations are performed using MP2 as well as dispersion corrected density functional theory (DFT) techniques. Our results show that the CO2 interaction goes from π-type...

Populations of genetically identical microorganisms residing in the same environment can display marked variability in their phenotypic traits; this phenomenon is termed phenotypic heterogeneity. The relevance of such heterogeneity in natural habitats is unknown, because phenotypic characterization of a sufficient number of single cells of the same species in complex microbial communities is te...

In the process of photosynthesis in Cklorella it is now known that the oxygen liberated during CO2 fixation and reduction originates from water (Ruben et al., 1941). I t is further known that in some algae (not ChloreUa) one can obtain carbon dioxide fixation and reduction without the release of oxygen (by adaptation to hydrogen, Gaffron, 1940, 1942 a, 1942 b, Gaffron and Rubin, 1942) and that ...