tion of pyridine nucleotides by spinach grana and coupled carbon dioxide fixation. Nature 167: 768769. 1951. 29. VISHNIAC, W. and OCHOA, S. Fixation of carbon dioxide coupled to the photochemical reduction of pyridine nucleotides bv chloroplast preparations. Jour. Biol. Chem. 195: 75-93. 1952. 30. ZBINOVSKY. V. and BURRIS. R. H. Metabolism of infiltrated organic acids by tobacco leaves. Plant P...

The first proof that heterotrophic, non-photosynthetic bacteria can fix carbon dioxide was presented in 1935 by Wood and Werkman (15). This investigation introduced the first experimental evidence that carbon dioxide serves as a building material in synthetic reactions of all forms of life, whether simple or complex. The synthesis of citric acid from oxalacetate by avian tissue was shown by Kre...

The strong advances in synthetic biology enable the engineering of novel functions and complex biological features in unprecedented ways, such as implementing synthetic autotrophic metabolism into heterotrophic hosts. A key challenge for the sustainable production of fuels and chemicals entails the engineering of synthetic autotrophic organisms that can effectively and efficiently fix carbon di...

Photosynthesis, Dark Fixation, /?-Carboxylation, C4-Metabolism, Brown Algae Marine brown macroalgae including Macrocystis integrifolia, Nereocystis luetkeana, Lessoniopsis littoralis, Laminaria saccharina, Fucus serratus and some further representatives of the Laminariales and Fucales (Phaeophyta) have been investigated with respect to their remarkably high potential for /?-carboxylation of pho...

The utilization of amino acids for growth and their effects on nitrogen fixation differ greatly among the several strains of each species of Azospirillum spp. that were examined. A. brasiliense grew poorly or not at all on glutamate, aspartate, serine, or histidine as the sole nitrogen and carbon sources. Nitrogen fixation by most A. brasiliense strains was inhibited only slightly even by 10 mM...

Nitrogen (N) accumulation rates in peatland ecosystems indicate significant biological atmospheric N2 fixation associated with Sphagnum mosses. Here, we show that the linkage between methanotrophic carbon cycling and N2 fixation may constitute an important mechanism in the rapid accumulation of N during the primary succession of peatlands. In our experimental stable isotope enrichment study, pr...

Trichodesmium, a colonial cyanobacterium typically associated with tropical waters, was observed between January and April 2014 in the western English Channel. Sequencing of the heterocyst differentiation (hetR) and 16S rRNA genes placed this community within the Clade IV Trichodesmium, an understudied clade previously found only in low numbers in warmer waters. Nitrogen fixation was not detect...

Many fundamental processes in the cell are performed by complex macromolecular assemblies that comprise a large number of proteins. Numerous macromolecular assemblies are structurally rather fragile and may suffer during purification, resulting in the partial dissociation of the complexes. These limitations can be overcome by chemical fixation of the assemblies, and recently introduced protocol...

The present study assesses the contribution of dark carbon fixation to the primary production in the oxic/anoxic interface of a shallow estuarine environment that develops a salt-water wedge with the presence of sulfide. Primary production was partitioned into oxygenic photosynthesis, anoxygenic photosynthesis and dark fixation. The results show the importance of dark fixation in the oxic/anoxi...

The legume-rhizobia symbiosis is a classical mutualism where fixed carbon and nitrogen are exchanged between the species. Nonetheless, the plant carbon that fuels nitrogen (N(2)) fixation could be diverted to rhizobial reproduction by 'cheaters'--rhizobial strains that fix less N(2) but potentially gain the benefit of fixation by other rhizobia. Host sanctions can decrease the relative fitness ...