Major sedimentary nutrient cycles Phosphorus cycle Sulphur cycle Major gaseous cycles Nitrogen Cycle Carbon Cycle Ammonification Nitrification Nitrogen fixation Symbiotic nitrogen fixation Non-symbiotic nitrogen fixation Photosynthesis Light reaction Dark reaction Carbon dioxide cycle Micronutrients Plant uptake of trace elements (essential and non-essential) Factors influencing micronutrient u...

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Chemoautotrophic symbioses, in which endosymbiotic bacteria are the major source of organic carbon for the host, are found in marine habitats where sulfide and oxygen coexist. The purpose of this study was to determine the influence of pH, alternate sulfur sources, and electron acceptors on carbon fixation and to investigate which form(s) of inorganic carbon is taken up and fixed by the gamma-p...

To assess the effects related to known and proposed biosynthetic pathways on the (13)C content of lipids and storage products of the photoautotrophic bacterium Chloroflexus aurantiacus, the isotopic compositions of bulk cell material, alkyl and isoprenoid lipids, and storage products such as glycogen and polyhydroxyalkanoic acids have been investigated. The bulk cell material was 13 per thousan...

Pyrolytic carbon has many properties that make it suitable for use in the replacement of small joints [1]. The material has a modulus of elasticity similar to that of bone, good wear and fatigue properties, and excellent biocompatibility. Its biggest disadvantage is inadequate biological fixation. The as-deposited surface of pyrolytic carbon has a pore size of 5-10 μm and a depth of 20 μm. This...

A large amount of energy is utilized by legume nodules for the fixation of nitrogen and assimilation of fixed nitrogen (ammonia) into organic compounds. The source of energy is provided in the form of photosynthates by the host plant. Phosphoenol pyruvate carboxylase (PEPC) enzyme, which is responsible for carbon dioxide fixation in C4 and crassulacean acid metabolism plants, has also been foun...

Carbon fixation refers to the conversion of carbon dioxide (CO2) to organic materials, as commonly performed in nature through photosynthesis by plants and other autotrophic organisms. The creation of artificial carbon fixation processes is one of the greatest challenges for chemistry to solve the critical environmental issue concerning the reduction of CO2 emissions. We have developed an elect...

Oceanic crust is a massive potential habitat for microbial life on Earth, yet our understanding of this ecosystem is limited due to difficulty in access. In particular, measurements of rates of microbial activity are sparse. We used stable carbon isotope incubations of crustal samples, coupled with functional gene analyses, to examine the potential for carbon fixation on oceanic crust. Both sea...

[1] Nutrients are supplied to the mixed layer of the open ocean by either atmospheric deposition or mixing from deeper waters, and these nutrients drive nitrogen and carbon fixation. To evaluate the importance of atmospheric deposition, we estimate marine nitrogen and carbon fixation from present‐day simulations of atmospheric deposition of nitrogen, phosphorus, and iron. These are compared wit...